Linde Technology January 2006

Transcription

Linde Technology January 2006
Reports on Science and Technology
January 2006
Linde Technology
LeadIng.
Featured topic: Energy
Natural gas from the Barents Sea
CO2-free coal power plant
Other topics:
Lift trucks in container port
Ionic compressors
Image credits: Adam Opel GmbH, OSV, p. 26 top | Affeldt, Joachim p. 12 | Bunnik Plants p. 40 | Corbis p. 20, 21 bottom,
23 top, 24, 25, 34 | Dockwise p. 13 left | Eurogate p. 35, 39 | RWE p. 14, 15, 16 | Shell p. 13 right | Statoil p. 7, 9, 10,
11 | Vattenfall Europe AG p. 19 | Zefa p. 6, 30 | The Linde Group is in possession of all other photographs.
Editorial
Dear Reader,
A lively discussion is under way about the Kyoto Protocol. The issues are important for our daily life, too:
What resources and technologies can we draw on to ensure our energy supply for the next 30 years? How
can global warming be halted in the face of rising world energy demand?
These questions also figure in the day-to-day work of Linde engineers as they search for innovative solutions
that will lead to the discovery of new energy sources and the more efficient use of existing ones.
Featured articles in this issue of Linde Technology therefore describe two forward-looking energy projects
demonstrating that growth and environmental protection can go together: Some 600 kilometers north of the
Arctic Circle, Europe’s biggest natural gas liquefaction plant is being built. The central module of the plant
has now reached northern Norway after a sea voyage of nearly 5,000 kilometers. And, in the framework of a
consortium, Linde experts are putting their know-how to work in developing a technology for CO2-free coalfired power plants.
Creative ideas for reducing CO2 emissions are also being found elsewhere, for example in a Dutch greenhouse.
Linde experts in Vienna have made a revolutionary advance in compressor technology, realizing an age-old dream
of engineers. And that Linde gases do not only have a beneficial effect on research and development but also
on our everyday life – often in a very subtle way – is shown by two application reports from the food industry.
We wish you an inspiring read.
Dr.-Ing. Aldo Belloni
Member of the Executive Board of Linde AG
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Cover photo:
Liquefied Natural Gas: Europe’s
biggest natural gas liquefaction
plant is under construction outside
Hammerfest harbor. Linde AG
supplied the heart of the facility, a
floating process unit with pumps,
gas turbines and heat exchangers.
Imprint
Published by: Linde AG, Wiesbaden www.linde.com
Editors: Stefan Metz, Linde AG (Editor-in-Chief);
Michael Kömpf and Dr. Karoline Stürmer, wissen & konzepte,
Regensburg
Layout, lithography and production: D+K Horst Repschläger
GmbH, Wiesbaden
Translation: eurocom Translation Services GmbH, Vienna
Printed by: HMS Druckhaus GmbH, Dreieich
Direct inquiries and orders to: Linde AG, Communication, P. O. Box 4020, 65030 Wiesbaden, Germany
or stefan.metz@linde.de
This series and other technical reports can be downloaded at www.linde.com/LindeTechnology. No part
of this publication may be reproduced or distributed electronically without the prior permission of the
publisher. Unless expressly permitted by law (and, in such instances, only when full reference is given
to the source) use of “Linde Technology” reports is not permitted without the publisher’s consent.
ISSN 1612-2232
Printed in Germany – January 2006
Contents
30_ Gases for foods: Strawberries, broccoli and
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34_ Movement in port: Linde lift trucks
40_ CO2 in plant growing: Linde technology is
shrimp stay fresh longer when packed under
are a key link in the logistics chain of
making an innovative contribution to
the proper gas.
an international port.
reducing CO2 emissions in the Netherlands.
4_ Linde News
Reports from the Linde world
Featured topic: Energy
6_ The gold of the Barents Sea
Construction of world’s northernmost LNG plant
12_ Giants of the sea
Modern ships ensure reliable natural gas supply
14_ Electricity without carbon dioxide
Linde helps develop the CO2-free coal power plant
20_ Elixir of life for Codfish & Co.
Linde technology aids fish farming
24_ Mobility under high pressure
Linde engineers develop ionic compressor
27_ “The demand is astounding”
Linde researcher Robert Adler on ionic compressors
30_ Fresh strawberries instead of sauerkraut from the barrel
Linde gases extend shelf life of foods
34_ One TEU to B3-82-00
Lift trucks at work in container port
40_ Greenhouse gas from the pipeline
Greenhouses use byproduct CO2 from oil refining
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Linde News
Order boom for Linde
In the past year, Linde received a number of noteworthy major orders. Order backlag reached
record levels at Linde Engineering, with business once again focused in the Middle East and Asia.
Here is an overview of the most significant orders from the second half of 2005.
Consortium leader, commissioned by
Bakhtar Petrochemical Company to build
two ethylene plants in Bandar Assaluyeh.
Annual capacity 1.2 million tonnes each.
Order value approximately 400 million
euros.
Dushanzi
China
I ra n
Bandar Assaluyeh
India
Al Jubail
Yanbu
Jamnagar
S a u d i -A ra b i a
Largest individual order for air separation
plants (order value more than 300 million
euros): One plant in Yanbu, one in
Al Jubail, each with a capacity of 3,000
tonnes of oxygen per day. Customer:
National Industrial Gas Company (NIGC).
Largest air separation plant in the
Middle East, producing 108,000 cubic
meters of oxygen per hour. Location: Al
Jubail. Order value: approximately 70
million euros. Customer: Mitsubishi Heavy
Industries Ltd.
China’s largest ethylene plant in
Dushanzi, annual production capacity:
one million tonnes of ethylene and
500,000 tonnes of propylene.
Order value: 140 million US dollars.
Customer: PetroChina International.
Consortium leader and licenser for ethylene plant in Al Jubail with annual production capacity of one million tonnes of
ethylene and 300,000 tonnes of propylene. Linde order value approximately
300 million euros. Customer: Consortium
led by Tasnee Petrochemicals.
Five new hydrogen plants in Jamnagar at
about 175 million US dollars in value.
Local production capacity (including with
two existing units): 600,000 standard
cubic meters of hydrogen per hour.
Customer: Reliance Industries Ltd.
Two polyethylene plants in Al Jubail with
total production capacity of 800,000
tonnes per year. Order value: 500 million
euros. Customer: Consortium led by
SABIC (Saudi Basic Industrial Corp.).
Linde takes over Spectra Gases
Commitment to a better future
Linde acquired the American specialty gas company Spectra
Gases, Inc. (Branchburg, New Jersey) in December 2005.
The transaction is subject to approval by the appropriate
anti-trust authorities. “This acquisition is part of the targeted
expansion of our product portfolio in the above-average
growth market for specialty gases,” according to Dr. Aldo
Belloni, member of the Linde AG executive board and
responsible for the business segment Gas and Engineering .
The U.S. company produces high-purity specialty gases and
chemicals, which are used in production and research as
well as for analysis. In addition, Spectra Gases makes special
gas mixtures, such as for the semiconductor industry and
for laser therapy. Linde was already building on its specialty
gases business in December 2004 with the majority takeover of the joint venture MNS Nippon Sanso.
Respect for human rights, maintaining labor standards, promoting environmental protection and fighting corruption:
Those are the aims of the United Nations’ Global Compact
initiative, which is involved in cooperation with companies
in the private sector. In September 2005, Linde AG joined this
worldwide alliance of organizations. In so doing, Linde AG
expressed its explicit support for the ten principles of the
Global Compact. These include, for example, the abolition
of child labor and promotion of environmentally friendly
technlogies. “This understanding is also reflected in our own
corporate principles on corporate responsibility,“ explained
Prof. Wolfgang Reitzle, President and CEO of Linde AG.
“Our principles compel us to act responsibly in terms of our
employees, society in general and the environment – worldwide, in every division and at every site.”
Linde Technology January 2006
New product makes room in the warehouse
With its new series of reach trucks, the developers at Linde Material
Handling have introduced a revolutionary truck concept: In the new
R14X-R17X models with 1.4 to 1.7 tonne load capacity, the mast is permanently fixed to the chassis. Instead of the whole mast unit moving
forward and back across the load legs, a traversing fork carriage performs
the load reach and tilt functions.
Unlike classic reach truck designs, in which the battery is placed
between operator and mast, the new location of the battery under the
driver’s seat offers numerous practical benefits, including a cabin
with double the space. Upright sections of the mast are set wide apart,
giving a significantly clearer and broader view of the path in front and
the load. The hydraulic mast locking means very high stability of the
mast, resulting in an increase in turnaround of up to 15 percent compared
to conventional reach trucks. These Linde X Range trucks made their
public debut at the CeMAT Hannover Fair in October 2005.
The newly developed reach truck makes
work easier in high-bay warehouses.
Prepared for high demand
Expansion progressing in the East
Hydrogen is considered as the most promising alternative to oil.
Linde is currently building Germany’s second hydrogen liquefaction
plant at the Leuna chemical site in the state of Saxony-Anhalt.
Because cryogenic liquid hydrogen (LH2) has a considerably higher
storage density than gaseous hydrogen, it is more efficient to store
and transport. Up to now, the semiconductor industry has been
one of its main consumers. But as hydrogen’s importance as an automotive fuel increases over the next few years, the demand for LH2
is expected to increase significantly. “Together with our partners we
currently work hard to set up a hydrogen infrastructure,” says Prof.
Wolfgang Reitzle, President and CEO of Linde AG.
After the EU’s eastern expansion, its new member countries
are growing increasingly interesting to western investors
and entrepreneurs, both as markets and as business locations.
Linde is now an important step closer to its goal of expanding its core gas business by ten percent per year. In the
Czech city of Vresova, located near Karlovy Vary (Carlsbad)
the country’s largest air separation plant was built for the
Sokolovska Uhelna energy company in September 2005.
At 62 million euros, the facility is the largest investment
ever made by the Linde subsidiary Linde Technoplyn, which
boasts a 65 percent market share of the Czech gas market.
Focus on sustainability
With its Corporate Responsibility Report, which appeared in October 2005, Linde
presented for the first time on a corporate-wide basis the company’s commitment
to four strategic areas of action: the Environment, Human Resurces, Society and the
Capital Market. “As a global player, we can only achieve success if our profit-oriented
action is balanced by the cornerstones of sustainable management – that means
environmental protection and social commitment,“ confirmed Prof. Wolfgang Reitzle,
President and CEO of Linde AG. The central issue in this first report is environmental
protection. The key tasks underlying this first Corporate Responsibility Report
also include the web-based compilation of key figures group-wide, the adoption of
a Corporate Responsibility Policy, and the introduction of a code of conduct for
employees.
Linde’s CR Report attests to the company’s initiatives in
environmental protection and its social commitment.
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Titelthema:
Featured topic:
Energie
Energy
World’s northernmost LNG plant under construction
The gold of the Barents Sea
On Melkøya, a tiny island just outside Hammerfest harbor in northern Norway, the largest
natural gas liquefaction plant in Europe is now going up. The facility will produce liquefied
natural gas for shipment to the U.S.A., France and Spain starting in June 2007.
Energy supplier: The Barents Sea is renowned not just for its rich
fisheries but also for its abundant deposits of natural gas.
Linde Technology January 2006
It seems as if the sun wants to leave a good last impression.
November is mild in Hammerfest, the sky a radiant blue. Here at
the northern tip of Norway, more than 600 kilometers beyond
the Arctic Circle, a long darkness will begin in a few days. The
sun will set behind the hills around the port, bringing on a polar
night lasting until February. The sky will be twilit, the air humid,
windy and cold. “The worst thing is the wind-chill factor, because
the wind blows nearly the whole time,” says Ernst-Jürgen
Kirscher. Wind chill makes perceived temperatures much lower
than actual ones; minus 5 degrees Celsius will feel like minus
30. Installers who have to work outside will experience great
hardship. Engineer Kirscher, Linde’s Project Director for Snøhvit,
belongs to the “Integrated Team,” which includes colleagues
from the Norwegian Statoil concern. This team will be responsible
for one of the most unusual plant construction projects in Europe:
erecting a natural gas liquefaction plant for the international
Snøhvit consortium under Statoil supervision. The plant covers
the whole island, some two kilometers long – an electric power
plant, huge tanks, steam generators, pipes more than one meter
in diameter, and the heart of the installation, the processing
plant with its liquefaction unit, a 62 meter tall monster of steel
and aluminum. Here, starting in 2007, natural gas from the
Barents Sea will be chilled to minus 163 degrees Celsius and
transformed to liquefied natural gas (LNG). It will then be carried
by ships to the U.S.A., France and Spain. Melkøya will be the
northernmost liquefaction plant in the world and the first giant
LNG plant in Europe.
LNG production under arctic condition
Europe has never been a significant LNG exporter. The major
players are Algeria, Indonesia, Malaysia and (for the last few
years) Qatar. In other words, the largest liquefaction plants have
always been located in warm regions.
“Building such a facility beyond the Arctic Circle is quite
another matter,” says Kirscher. Hammerfest can have as much as
two meters of snow on the ground in wintertime. Rain, storms
and humidity make work a trial. Darkness and permafrost add
to the difficulty. Anyone who works here must be able to hold
a welding torch for hours even in chilling cold. Work saps
everyone’s powers. Those who work outdoors therefore get a
break after fourteen days, journeying home for two weeks’ rest.
Hammerfest has a permanent population of about 6,000 but now
is temporary home to another 2,500. They work on Melkøya and
live on board hotel ships in the harbor, in dormitory containers,
or in guest houses or the few hotels the place offers. Kirscher
and his Statoil colleagues manage this huge workforce. Linde
designed the liquefaction plant, and its Munich-based engineers
must now make sure that the installation work meets their
specifications.
From a bird’s-eye view, it might seem that everything on
the island is done, because the entire area is jam-packed with
structures. But the plant still lacks the breath of life. Work planned
for the frigid months ahead will mostly take place indoors. The
installation of electronics, switching and control equipment is
scheduled from December to February. Outdoor hookups – the
connection and interlinking of preassembled plant units – will
proceed as weather permits. This is not as easy as it sounds,
because those prefabricated units are gigantic and had to be
Protected from wind and water: The builders of Melkøya will have logged some
nine million work hours by the time the plant enters service in 2007.
shipped north by sea before they could be hooked up. The harsh
climate and remoteness of northern Norway dictated shifting
work to southern and central Europe, for example to Cádiz in
southern Spain, whenever possible. Work on the process barge,
the most imposing part of the whole installation, began in the
Dragados Offshore yard at Cádiz early in 2004. The steel hull of
the barge is 9 meters deep, 154 meters long and 54 meters wide.
It took just 18 months to build a multilevel steel framework
on it and install the 45 pumps, 5 gas turbines, heat exchangers
and compressors. The gas turbines will drive generators to
provide the Melkøya plant with electric power. The power plant
is rated at some 224 megawatts, enough to serve a small city of
40,000 inhabitants. “Because the various parts were fabricated
at many sites, in France and Italy and elsewhere, we had to
plan the project so that everything would arrive in Cádiz at the
proper time,” recalls Hermann Spiller, coordinator for implementation of Linde’s design at the Dragados yard. “A facility as
complex as this one can be finished on schedule only if the
bulk of the individual components are prefabricated and ready
to install.” The achievement is one of engineering as well as
logistics, for all the components must be at the right place
at the right time and also must take up a minimum of storage
area. For example, the levels of the steel skeleton were prefabricated as “pancakes.” Weighing up to 300 tonnes, these
frames serve as decks separating the levels. When the time
came for installation of each pancake, all the parts located
below it – pumps, compressors, tanks and major piping sections
– had to be in place already. “Naturally, when the lid is put on,
everything underneath has to be complete,” explains Spiller.
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Featured topic: Energy
Hammerfest
Assembly puzzle: Components of the liquefaction plant
were pre-assembled at eight major sites in Europe.
Melkøya, Norway: Blasting, site preparation, excavation
of process barge dock, construction of tanks, coolant tunnel,
operations building and underwater access tunnel
Bremen, Germany: Fabrication of cold box modules
Bremen
Zwijndrecht
Antwerp, Belgium: Final assembly and shipping of cold box
Zwijndrecht, Netherlands: Fabrication of slug catcher
Antwerpen/
Hoboken
Schalchen
Hoboken, Belgium: Fabrication of miscellaneous components
and pipe bridges
Schalchen, Germany: Fabrication of cryogenic heat
Ferrol
exchangers
Massa
Massa and Florence, Italy: Fabrication of gas turbines
and compressors
Ferrol, Spain: Assembly of barge (steel hull)
Cádiz, Spain: Installation of process plant on barge
Cádiz
Steel colossus on a journey
Once completed, the barge had to travel by sea 2,700 nautical
miles (5,000 kilometers) to Hammerfest. An exceptionally compact design was called for, and the engineers had to deal with
some special challenges. Plants located on solid ground usually
have ample room, so components are simply set down one
next to another. On the barge, the designers had to lay everything out in multiple narrow stories. What is more, the glistening
patchwork of equipment, 30 meters tall, had to be seaworthy.
Spiller says, “During such a long voyage, the ship rocks back and
forth 110,000 times, and the plant had to be able to withstand
this motion.” Steel must not suffer fatigue, and no component
could be allowed to break loose from its mounting. In the end, it
took the engineers almost a year to devise a compact design
that could endure the wave. And the Linde engineers had
yet another problem to address. In Cádiz harbor, the barge was
flooded and grounded in order to prevent the steel hull from
moving while construction work was being done. Currents washed
away the bottom beneath it, so that the colossus sagged
unevenly. The height difference between the ends of the barge
was as great as 20 centimeters at times. “It was bent like a
banana,” says Spiller. In the planning phase, the engineers had
already allowed for its recovery when water was pumped from
individual compartments and the huge hull regained buoyancy.
“We adapted the steel structure and built in expansion joints
like those in a highway bridge, so that the movement could
even itself out,” says Spiller. Another tricky point had to do with
heavy loads lowered onto the deck, which would also have
flexed the barge. The heaviest load placed by a crane during
construction was 450 tonnes. To deal with this problem, the
experts used differential flooding of the hull compartments to
keep the giant barge at equilibrium. The barge weighed 35,000
tonnes, as much as 500 diesel locomotives, when it was finally
towed into the Gulf of Cádiz for transport to Hammerfest.
Next, a heavy-lift vessel (HLV) carried the barge piggyback
from the Mediterranean to Hammerfest, a voyage of 11 days.
Wind and waves represented the greatest challenge, but the
experts had equipped the behemoth well. The cargo was stabilized
with some 60 tonnes of steel, and specially installed sensors
reported any motion that might point to shifting. Safe harbors were
identified where the vessel could take shelter in case of excessively
rough seas. When the HLV arrived in northern Norway, specialists
used harbor tugs and two strong cable winches to remove the
barge and tow it to its final position in an enlarged dock on
Melkøya. The barge has since been lowered onto individual concrete foundations, the dock pumped dry and filled with gravel.
There is nothing to remind the viewer of its birth in southern
Spain. “It looks as if the plant was built right on the island,” says
Kirscher. Workers have even installed a heating system on the
barge now so that supply and evacuation routes will remain free
of ice and snow and the operators can move about safely.
Cold box from Antwerp
Shortly before the process barge, the heart of the entire LNG
plant arrived, also by sea: the “cold box.” This is where liquefaction actually takes place as natural gas is chilled from around
40 degrees to minus 163 degrees Celsius. The name does not
suggest how big this unit is. It measures some 62 meters in
height and is the size of a narrow office building. It is made up
of four individual boxes, which were joined into one at Antwerp.
Inside these boxes are countercurrent heat exchangers, still
towers and separators, along with piping and instrumentation.
Linde Technology January 2006
Arrived: In mid-2005 the process barge reached its destination of Melkøya after a sea voyage of some 5,000 kilometers.
Extreme operating temperatures dictate the use of aluminum
and stainless steel as the chief materials for these components.
Gas flowing through the heat exchangers is progressively cooled
down until it liquefies and shrinks to one six-hundredth of its
original volume. The gas is purified before cooling, of course,
because impurities such as water would freeze out and plug the
equipment. Mercury – a metal present in trace amounts in the
gas stream, threatening to corrode the pipes over time – is also
removed. To maintain the low temperature inside the box, it is
necessary to minimize cold losses through its walls, and so the
entire unit is packed with powdered perlite, a mineral that has
very good insulating qualities.
Crab-profiled and remotely controlled
Gas is conveyed to Melkøya via pipeline from 140 kilometers
away in the Barents Sea, where the production platform sits on
the sea floor. Starting in 2007, three gas fields will be tapped,
one after another: first Snøhvit (which bears the Norwegian name
of the fairy-tale character Snow White and lends the project
its name), then Askeladd and Albatross. The subsea production
platform, lying at a depth of some 300 meters, is unusual in
having no crew on site; it is remotely controlled from Melkøya.
The sturdy structure keeps a low profile, crab-fashion, in order
to protect itself against damage from the ground trawl nets
of the fishing fleet. The remote control system is now being
installed on Melkøya, and the first technicians are already
practicing on a simulator to learn how to operate the equipment
on the sea floor
The managers at Melkøya have to keep a close eye on
the workers for some months yet. The hookup phase entails
seating every valve, connecting the process barge to the rest
of the plant, welding hundreds of pipes and checking them
for absolute tightness, and laying power lines and data cables.
Kirscher sums up this phase of the work: “We make certain
nothing has come loose during the sea voyage; we climb into
the big tanks to see that they are in order; we clean the pipes;
we complete welded and flanged unions.”
Six billion cubic meters of liquefied natural gas
Melkøya is a costly project. The people here will log some nine
million hours of work by the time the first ship departs with the
Liquefied petroleum gas or liquefied
natural gas – a crucial difference
Natural gas is a natural product occurring in
underground deposits. In terms of composition,
it is more than 90 percent methane (CH4).
Natural gas retains its gaseous form down to
a temperature of minus 162 degrees Celsius.
Below this point it becomes a liquid and
occupies a far smaller volume. In this form it
is referred to as LNG, liquefied natural gas.
Liquefied petroleum gas (LPG), made up
chiefly of propane or butane, is a byproduct
of gasoline and diesel fuel refining. It remains
a liquid under low pressure and can be stored
and transferred in appropriate vessels.
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Featured topic: Energy
Storage tanks
Wharf for LNG carriers
Process barge with
pumps, gas turbines
and heat exchangers
Major construction site: Building the LNG plant entailed blasting 2.3 million cubic meters of rock on Melkøya Island.
first LNG cargo in summer 2007. But the project will pay off:
Statoil projects exports of around six billion cubic meters of LNG
annually over a span of 30 years. Of this, 2.6 billion cubic meters
will go to the U.S. market, 1.7 to France and 1.6 to Spain. Experts
think Statoil and the whole Snøhvit consortium are in a growing
market and that LNG will become much more important in years
to come. The International Energy Agency (IEA) in Paris estimates
that world natural gas demand will grow by 3.5 percent per
year up to 2020 and that natural gas will account for a quarter
of world energy demand in that year. While the great bulk of
this will be in gaseous form, LNG will show substantial gains.
Figures from the Groupe International des Importateurs de Gaz
Naturel Liquéfié (GIIGNL) show LNG already making up a fourth
of the international natural gas business. While world LNG volume
has grown around eight percent a year in the past, in future
the rate of increase may reach as much as ten per cent a year.
The Swiss banking house Julius Bär attributes the rising
popularity of LNG to (among other factors) the narrowing scope
of opportunities for companies in the oil market as the rate of
success for exploratory wells drops. At the same time, gas
reserves in the U.S.A. and Great Britain are already strained and,
indeed, dwindling. Supplies are becoming scarcer.
Because natural gas pipelines longer than 3,000 kilometers
are not profitable, LNG shipping is the most practicable form of
transport to the U.S.A. It is true that the lion’s share of world
natural gas reserves – some 41 percent – rests beneath the desert
sands of the Arabian Peninsula, but still the Melkøya terminal
establishes the Norwegians and their consortium partners in a
business that is about to boom. Against this background, it is
easy to understand why the crews at Melkøya are confronting
the weather – the storms and the wind-chill factor. I
Freelance science journalist Tim Schröder lives in Oldenburg.
He writes for outlets including Neue Zürcher Zeitung, Bild der
Wissenschaft and Mare.
Links for further reading:
www.hydrocarbons-technology.com/
www.statoil.com
Linde Technology January 2006
Our story so far…
1981 – Gas fields are discovered in the Barents Sea.
Melkøya, September 2002
1995 – Study phase commences with feasibility analyses and selection of
partners to cooperate with Statoil.
1996 – Statoil and Linde form LNG technology alliance to develop the mixed
fluid cascade (MFC) liquefaction process.
December 2000 – Pre-engineering phase begins: the plant design takes
concrete form.
Shipping of the cold box to Melkøya
January 2002 to present – In the engineering phase, construction gets under
way. First site work is blasting, which turns Melkøya from a barren island into
a made-to-order construction platform. Rock removed amounts to 2.3 million
cubic meters (including road tunnel to mainland), enough to fill the Great
Pyramid to the tip. Volume of concrete eventually placed is 60,000 cubic meters.
August 2002 – Construction phase begins as plant components are built at
Melkøya and elsewhere in Europe.
July 2003 – At La Coruña, Spain, the process barge is launched on 11 July.
Pumps, heat exchangers, compressors, and the power plant with its five gas
turbines will later be installed on this huge “floating island.”
2003 – Installation work on the barge begins at Cádiz.
The process barge under way for Cádiz
June 2004 – The “slug catcher” is finished at Zwijndrecht, Netherlands. This
system of large branched pipes separates entrained moisture and sludges from
gas delivered via the pipeline.
August 2004 – Monoethylene glycol tanks are finished in Sicily and soon
afterward shipped to Hammerfest. A pipeline carries monoethylene glycol from
the island to the well, where it is added to the mixture of gas, water and
condensate. Its function is to prevent the formation of solid hydrates at the
wellhead and during transport to land.
The process barge at Cádiz
April 2005 – The cold box, the liquefier proper, is finished at Antwerp. The
heart of the LNG plant, this unit was prefabricated at Linde's Schalchen works
(in Bavaria) and at Bremen; final assembly took place in Belgium. The 62
meter tall tower is next carried to Hammerfest by a heavy-lift vessel (HLV).
June 2005 – Workers at the Cádiz yard finish the topside, the superstructure
on the process barge. In the Gulf of Cádiz the barge, now weighing 35,000
tonnes, is loaded piggyback-fashion on the HLV Blue Marlin.
June 2005 – The barge is secured on board Blue Marlin and departs the Gulf
of Cádiz on 30 June, bound for Hammerfest. The voyage lasts eleven days. The
ship carrying the finished process barge travels 2,700 nautical miles.
…and what comes next
Shipping of heat exchangers on the Danube
By the end of 2006 – Mechanical completion of the Melkøya plant is marked.
In the commissioning phase that follows, a rigorous, system-by-system program
of checks and tests is carried out.
June 2007 – The plant comes on stream.
December 2007 – The plant is accepted for commercial production. LNG
production is to continue for as much as 30 years.
The integrated process barge at Melkøya, mid-2005
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12
Featured topic: Energy
Modern marine engineering ensures natural gas supply
Giants of the Sea
World demand for natural gas is rising dramatically. But not every high-demand region
can be supplied by gas pipelines. Huge tankers help out by transporting liquefied natural
gas (LNG) all over the world by sea. The needed processing equipment can be carried
by heavy-lift vessels (HLVs). These important cargo ships are vital to the growth of the
natural gas industry.
LNG in transit: “Moss sphere”
carriers bear liquefied natural
gas across the oceans in these
aluminum spheres.
The transportation of liquefied natural gas (LNG) is a business
of vast proportions. Huge tankers carry LNG around the globe.
The imposing steel hulls of these ships commonly measure 300
meters long – about the length of three football fields – and 50
meters in beam, so big that the Arc de Triomphe of Paris could
be stowed in the hold. Some 180 LNG carriers are cruising the
oceans at present. In the future, however, there will be many
more, because dwindling crude oil reserves and rising prices are
making natural gas a more and more important resource.
Liquefied natural gas will be the fuel of choice above all
for utilities in regions too remote to be linked by pipeline to the
world’s great natural gas reserves – the U.S.A. for example.
LNG has this advantage: at a temperature of minus 163 degrees
Celsius, it is 600 times denser than natural gas in its natural
form. It therefore occupies a much smaller volume in transport.
E. A. Gibson Shipbrokers Ltd., a respected London firm,
estimates that world LNG volume, which stood at 142 million
tonnes in 2004, will more than double to 346 million tonnes in
the year 2015. Gibson estimates the demand for ships in 2015
at more than 350, again twice the present figure. It is thus
no surprise to learn that the major builders of LNG tankers are
carrying full order books. In the 1980s, most LNG carriers still
came from European shipyards; today’s biggest builders are in
Korea and Japan. The Koreans have now become the leaders
in LNG carrier construction. In Daewoo Shipbuilding & Marine,
Samsung Heavy Industries and Hyundai Heavy Industries, South
Korea now boasts the three most important manufacturers
of LNG carriers in the world. Each of these concerns is now launching at least seven new LNG tankers annually.
As technically demanding as a spacecraft
LNG carriers come in two forms: Moss tankers with spherical
reservoirs, and membrane tankers. The Moss sphere is the
classical design and the one used more frequently. Huge aluminum
spheres up to 40 meters in diameter rest inside the ship’s hull.
The optimized spherical shape makes these containers inherently
stable, and so they can be made from thin material – just four
centimeters of aluminum – without additional reinforcement. For
comparison, scaling a chicken’s egg up to this size would result
in a shell at least 30 centimeters thick. With added insulation,
this layer of aluminum is enough to hold the LNG at minus 163
degrees Celsius. The newer membrane carriers take a different
design approach, using double-walled tanks. The innermost
layer is most commonly a metal membrane 0.7 to 1 mm thick,
which seals the tank. Behind it is an insulating layer made from
a material such as plywood or balsa. Insulation performance is
improved by the addition of a second layer of aluminum, glass
fibers and polyurethane to make a sandwich. Shipyards are now
Linde Technology January 2006
building more membrane carriers than Moss spheres, on the
strength of a Hyundai Heavy Industries study that found a gain of
as much as eight percent in LNG capacity for membrane carriers
over aluminum sphere vessels of equal size.
The construction of membrane-style carriers is a high art,
“comparable with building a spaceship,” according to John
Holland, Special Projects Manager in the Marine Engineering
Division of Germanischer Lloyd in Hamburg. The membranes
must be fabricated and welded to millimeter precision. Corners
and edges are made so that they can expand and contract without
cracking when wide temperature swings occur. What is more,
the steels now used for the membranes are qualities that vary
little in their thermal expansion coefficient between 20 above
future until they are economical even in smaller carriers. The
picture of maritime LNG trading is not completed by LNG carriers,
though. Also prominent are heavy-lift vessels (HLVs), which can
transport extraordinarily heavy cargoes. This class of ship, as impressive as it is unusual, found use in bringing components for the
Melkøya Island LNG terminal to Hammerfest from the yards where
they were built in Cádiz and Antwerp. Last summer, Blue Marlin
sailed from the Netherlands to Cádiz, where it picked up the
35,000 tonne process barge, a key component of the new terminal. Blue Marlin, one of the world’s largest HLVs, has a cargo deck
measuring 178 by 63 meters. While loading, the ship partially submerged itself so that, for a short time, only the superstructure was
visible above the water. Tugs then maneuvered the barge above
Flat bed truck of the sea: “Black Marlin” is one of the world’s largest
Complex technology: Modern membrane carriers employ the
heavy-lift vessels (HLVs).
complicated sandwich construction for their tanks.
and 163 degrees below zero Celsius. These qualities include
Invar steels such as those employed in tankers of the Gaz-Transport design.
the deck. When the HLV pumped out ballast and resurfaced, the
barge rose along with it. Yard workers welded some 60
“scotches” (retaining wedges), each a meter and a half tall, onto
the sides of the barge to keep it from shifting in heavy seas. This
done, the vessel sailed to Hammerfest, a voyage of 2,700 nautical
miles, where it repeated its submerge-and-surface cycle to unload.
HLVs have been employed primarily in high-seas operations;
the erection of offshore drilling platforms is one example. But they
can transport other kinds of burdens: cranes, entire warships
or, for that matter, up to 15 motor yachts at a time. The voyage to
Melkøya shows that these gigantic carriers will be able to carry
out quite different tasks in years to come and will become a pillar
of the future LNG industry. I
250,000 cubic meters of LNG per carrier
An average carrier now has a capacity of some 150,000 cubic
meters of LNG. Growth in the business, however, has led to orders
for vessels having cargo capacities as large as 250,000 cubic
meters. These have some technical peculiarities. Unlike all other
cargo vessels, LNG carriers usually have steam turbine propulsion.
Their boilers are fired with boil-off gas (BOG), that is, gas vaporized
from the LNG being transported. As a rule, 0.15 percent of the
cargo boils off every day. LNG carriers in the past have thus
powered their machinery by making direct use of their cargo. In
the new supercarriers, however, the amount of BOG is more
than the propulsion system can use, and so these vessels will be
equipped with reliquefaction plants. High-efficiency, slow-speed
diesel engines will provide motive power. “Reliquefaction systems
have generally been too expensive,” says Holland. “On the one
hand, they have a high first cost; on the other, their compressors
consume about five megawatts of electric power.” But it will pay
to install these systems in the new generation of 200,000-plus
cubic meter carriers. Holland thinks that reliquefaction plants will
soon become established and that their costs will drop in the
Freelance science journalist Tim Schröder lives in Oldenburg.
He writes for outlets including Neue Zürcher Zeitung, Bild der
Wissenschaft and Mare.
Links for further reading:
www.ship-technology.com
www.dockwise.com
www.shi.samsung.co.kr
english.hhi.co.kr
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Featured topic: Energy
Linde collaborates on emission-free coal-fired power plant
Electricity without carbon dioxide
Laboratories, utilities and engineers all over the world are working on concepts for
CO2-free coal-fired power plants. The keys to clean energy are the use of pure oxygen
for combustion or gasification and the liquefaction and storage of product carbon
dioxide. Linde is involved in many national and international projects, including a pilot
plant for the Vattenfall electric power concern, scheduled to come on line in 2008.
Germany is regarded as a global leader in environmental protection. In terms of greenhouse gas emissions, for instance, the
country has lowered its output of carbon dioxide by 19 percent
since 1990 and will attain a 21 percent reduction by 2012.
The trend is in the right direction. But the lion’s share of this
abatement has been due to the closure of industrial and power
plants in the new German states. The conservation group World
Wide Fund for Nature (WWF) holds that Germany has fallen
behind in some aspects of climate protection. One WWF study
Optimized plant technology: RWE’s Niederaussem power plant
near Cologne.
showed that five of the ten highest-emitting power plants in
Europe stand on German soil. Experts do not find this result
surprising. All the plants in question are fueled with brown coal
(lignite), and “Lignite is a very high-CO2 energy to begin with,”
says Stefan Lechtenböhmer of the Wuppertal Institute for Climate,
Environment and Energy.
“Global climate change is the biggest challenge for environmental policy today,” maintains Lars G. Josefsson, president
of Vattenfall. He sees this as the main theme in his company’s
environmental efforts. Business considerations play a role too, of
course. The Swedish concern has taken over lignite mining and
power generation in the new German states and would like to
continue using this cheap fuel. Its goal is shared by RWE, which
is in a similar business position in the state of North Rhine-Westphalia. Brown coal accounts for a large share of electrical power
output in Germany, some 27 percent.
In years to come, part of the problem may vanish into thin
air – literally. Germany must replace generating capacity of
around 40 gigawatts by 2020, as older fossil-fuel plants reach
the end of their lives while energy demand rises. Since a large
plant supplies about one gigawatt, it will take at least 40 of
them just to modernize the installed base.
CCGT power plants for the future
What technology and what fuel will utilities adopt? With regard
to CO2 emissions, the case seems clear: The use of “combinedcycle gas turbine” (CCGT) plants can yield a saving of 48 percent
relative to the coal-fired plants replaced in the coming modernization campaign. A CCGT plant burns natural gas in a gas turbine
and then, from the residual heat, extracts enough energy to
drive steam turbines and generate additional power. Such plants
today have efficiencies of 58 percent, far better than those
of plants burning bituminous coal (48 percent) and lignite (43
percent). Higher efficiency also means lower CO2 emissions.
What is more, cost arguments favor CCGT technology, since the
investment cost of 400 euro per kilowatt of capacity is substantially less than the 700 euro per kilowatt for coal-fired plants.
In view of these advantages, the European Union (EU) projects
that the fuel mix will shift toward natural gas while lignite
consumption stagnates, with bituminous coal regaining ground
after a low around 2010.
Rising natural gas prices, however, cast doubt on this
forecast. The price of natural gas has more than doubled since
Linde Technology January 2006
Still hand-labor: removal of the inductor for
a full-flow measurement.
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Featured topic: Energy
September 11, 2001. Although there is no consensus as to
whether crude oil and natural gas prices are linked, present
knowledge still suggests that the world’s reserves of natural gas
will last only a few decades longer than those of petroleum. In
contrast, there is enough bituminous coal and lignite to last at
least 300 years, and with these there is no danger of terrorist
attacks on pipelines. The EU study “World Energy, Technology
and Climate Policy Outlook” therefore projects stable coal prices
out to 2030. A reassessment is also taking place in the U.S.A.,
where many gas-fired plants have been built in recent years.
Domestic natural gas is no longer sufficient to satisfy the rising
demand for energy, and imports will be needed in the future.
Coal, on the other hand, is plentiful, and so the U.S. government’s Clean Coal Power Initiative calls for the construction of
two billion dollars’ worth of new coal-fired plants over ten years.
The more power plants are fueled with coal, the more
pressing the CO2 problem will become. If the entire world’s
estimated reserves of coal – 5 trillion tonnes – were burned, the
amount of carbon dioxide released into the atmosphere would
be 17 times as much as the total for the past 150 years. This is
the outcome that engineers seek to prevent through new concepts.
Lignite-fired plants using “optimized plant technology” (BoA)
are already in service. RWE’s Niederaussem facility in North RhineWestphalia – the most modern in Germany with a capacity of
965 megawatts and an efficiency of 43 percent – employs this
principle. BoA facilities emit 30 percent less CO2 than older
plants chiefly by virtue of two practices: drying the feed lignite
to boost efficiency and increasing the steam temperature at the
turbine inlet. This alone, however, will not be enough to abate
greenhouse gas emissions significantly. The only way for coalfired plants to achieve this goal is to release no carbon dioxide
into the atmosphere in the first place. All the industrialized
countries are therefore working on CO2 capture, and numerous
research projects on this topic have been started in recent years.
There are three options for removing carbon dioxide:
1. Post combustion. This method has the advantage that it can
be retrofitted to older power plants. Many plants already have
carbon dioxide scrubbers, usually not for environmental reasons
but to secure CO2 for use in oilfields or in the food processing
industry. Flue gas from the power plant is passed through a
solvent such as ethanolamine. The spent scrub liquor is then
heated to release CO2, which is liquefied by compression. The
result, however, is a loss of efficiency, as much as 14 percentage
points, so that more coal must be burned in order to get the
needed output. In the EU’s CASTOR project, engineers are
designing a higher-efficiency pilot installation that can handle
the off-gas streams from a large power plant.
2. Pre combustion. The greatest obstacle to carbon
dioxide capture is the large amount of nitrogen in the combustion
air. This nitrogen must be transported through the power plant
but plays no part in the combustion process. The IGCC (integrated
gasification combined cycle) process works with a much lower
level of nitrogen. Pulverized coal and pure oxygen are reacted
to yield a synthesis gas made up primarily of carbon monoxide,
hydrogen, carbon dioxide and water vapor. The admission of
further steam converts most of the carbon monoxide to carbon
dioxide and hydrogen. CO2 is now easily captured, while the
hydrogen is used to fire a gas turbine.
Engineering firms such as Siemens and Alstom are developing the IGCC technology, and projects like ENCAP, funded
by the EU, and the German COORETEC initiative – aim to create
power plant designs using gas turbines capable of withstanding
the hot hydrogen flame. Many gasification systems – this is one
of Linde’s core competencies – are already used in refineries
because they can handle not only coal but also heavy oil and
even asphalt. The technology has not yet gained acceptance in
power plants, and work toward improving the overall reliability
is still under way.
Oversized technology: inspection of a flue-gas duct.
Everything under control: the control room of RWE’s Niederaussem power plant.
Linde Technology January 2006
3. Oxyfuel. The Oxyfuel process, in which coal is burned
with oxygen, is a middle way. Because the combustion
temperature with pure oxygen would shoot up to 2,700 degrees
Celsius, while today’s steam turbines can handle only 650
degrees, a portion of the off-gas is recycled and used to dilute
the oxygen in order to control the temperature. The nitrogen
burden is eliminated at the outset, so the carbon dioxide
concentration in the flue gas increases to some 73 percent,
making it easier to capture, liquefy and ship the CO2. The
Oxyfuel concept is under study by 20 partners in the ENCAP
and COORETEC projects.
Oxyfuel on the test stand
The Oxyfuel concept has recently received a boost. At the
Schwarze Pumpe site in the Lausitz (easternmost Germany),
Vattenfall will build a 30 megawatt pilot plant, slated for startup
in 2008. This facility, costing 40 million euro, will demonstrate
that the Oxyfuel process will work in the context of power plant
operations with all their complexity.
If everything goes as planned, the next decade will see an
Oxyfuel demonstration plant with an output of 250 to 600
megawatts, and a 1,000 megawatt commercial facility offering
competitive generation costs will go into service in 2020. In the
Oxycoal project, companies such as RWE, E.ON and Linde are
already working – under the leadership of the Rhine-Westphalia
Technical University (RWTH) in Aachen – to realize the concept
of an advanced coal-dust-fired power plant.
The Oxyfuel and IGCC plant concepts offer a new market of
interest to Linde. After all, know-how in the generation and
handling of gases will be crucial when coal is not burned with
air but is either combusted with pure oxygen or converted with
it to synthesis gas.
“Separating air is like distilling liquor, only at minus 180
degrees Celsius,” says Dr. Harald Ranke, Research and Development manager in Linde’s Engineering division. After the air is
cooled to this low temperature, controlled heating and cooling
cause oxygen and nitrogen to condense out of it in different
parts of the system. Depending on the purity target, noble gases
and valuable trace gases such as argon, xenon and krypton can
also be produced in the same way.
Linde is the worldwide market leader in the construction
of air separators. Even though Linde engineers have mastered
all the details of air separation, future IGCC and Oxyfuel power
plants will pose enormous new challenges to the technology.
Today’s largest installations deliver 5,000 tonnes of oxygen per
day, enough for an Oxyfuel plant rated at some 300 megawatts.
A typical gigawatt Oxyfuel plant would therefore need three
of the largest air separating systems. The cryogenic process in
an IGCC or Oxyfuel power plant would cost from seven to eleven
percentage points of efficiency, and so the integration of air
separation into power plant operations must be optimized.
Membrane separators for high temperatures
The solution may lie in so-called membrane separators. In such a
unit, a ceramic membrane separates oxygen from the air; the
process may save energy in comparison with a destillation-type
air separator. The partial pressure of oxygen is the sole driving
force causing the gas to migrate through the dense ceramic to
the other, oxygen-poor side. This sounds simple, but in reality
it is a major challenge. Separation takes place at temperatures
as high as 900 degrees Celsius. The ceramic must be able to
withstand mechanical stresses and chemical attacks at these
temperatures in continuous service, and this goal has not yet
been attained. Several companies, chiefly American, are hard
at work on this technology but have not achieved a breakthrough that would lead to a commercial product. Linde is also
working on membrane separators in the context of a project
for the German Federal Ministry for Education and Research.
The resulting know-how will find use in the power plants being
designed in the Oxycoal project, among others.
CO2 belongs underground
The decisive factor for the efficiency of an air separator, no
matter of what type, will be that it is integrated as neatly as
possible into the power plant. In many industries, Linde owns
and operates air separators for oxygen generation and steam
reformers for hydrogen generation, selling the gases to the
World electric power generation
Contributions of primary energy sources to world power output.
Source: Vattenfall AB
Others 1.6%
Fossil fuels 64.4%
Nuclear 16.9%
Hydroelectric 17.1%
Breakdown of costs for CO2 capture, storage and transport
Source: Vattenfall AB
Storage
Capture
Transport
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Featured topic: Energy
A future without CO2: Linde air separators like the one in Leuna, shown here, supply oxygen for many
applications including clean electric power.
customer at fixed prices; energy utilities, on the other hand,
wish to operate their own equipment. This makes sense because
the power plant supplies mechanical and electrical energy for
the air separator in the first place, and seamless integration
will prevent energy losses. “Linde will work with the utilities to
develop new business models in this area,” Ranke promises.
In a future CO2-free power plant, carbon dioxide capture is
only half the story. Simply blowing it off into the air would mean
no benefit in climate protection; this is especially true of the
Oxyfuel process.
The greenhouse gas therefore has to be permanently
confined (sequestered). The most obvious choice is to pump the
carbon dioxide into oil or gas fields, where it will raise the
pressure in the formation and thus boost yield. In countries that
impose high CO2 taxes or where emission rights are traded, this
is a way to save a lot of money. The Norwegian company Statoil,
for example, injects a million tonnes of CO2, unavoidably produced
from natural gas fields, back beneath the sea floor every year,
thus saving eight-figure sums. Statoil estimates that the Utsira
rock formation in the North Sea could hold 600 billion tonnes of
CO2, as much as would be emitted over the next 600 years by
all the power plants now operating in Europe.
Another option is to inject the CO2 into mined-out coal seams
or salt domes. At Ketzin, near Berlin, 2006 will see the inception
of the CO2-Sink project, coordinated by the Potsdam Georesearch
Center. Carbon dioxide will be injected into a salt dome there on
a test basis. Here again, Linde will participate by furnishing CO2
as well as liquefaction, storage and vaporization technology. This
effort would ideally be linked to Vattenfall’s Oxyfuel pilot plant,
but that facility will not enter service until mid-2008.
Because it is near a large city, CO2-Sink is likely to raise
many questions about the permitting process and public
acceptance. The public at present knows almost nothing about
CO2 sequestration, so special effort needs to be put into
convincing people that carbon dioxide can be safely confined
underground for centuries to come. Geologists predict that
the gas will gradually combine with potassium salts present
in the formation, forming harmless limestone and thus being
rendered innocuous.
A question of economics
Just as important to the success of CO2 capture as the surmounting of technical obstacles, however, is whether the process can
be carried out economically. At present it costs between 30 and
40 euros to capture one tonne of CO2; 6 to 15 euros to transport
it 100 kilometers in high-pressure pipelines; and another 10 to
25 euros to store it underground. These expenses would increase
the cost of electricity by 0.015 to 0.06 euros per kilowatt-hour.
Vattenfall is seeking to lower long-term costs dramatically with
the Oxyfuel process, projecting around 20 euros per tonne of CO2.
At the same time, prices in the emissions market are on
the rise. The cost of emission rights per tonne of CO2 – 20 to 30
euros in the European market – is “more than was first anticipated for this point in time,” says Karoline Rogge of the Fraunhofer
Institute for Systems and Innovation Research in Karlsruhe, which
advises the German government on the granting of certificates.
Frank Haffner, a Siemens energy strategist, is optimistic: “The
two opposing trends should make CO2 capture economical in 15
to 20 years.” The Americans are also looking to this trend; their
FutureGen Initiative is set to build the world’s first CO2-free IGCC
Linde Technology January 2006
19
CO2
Electricity
CO2
Coal
Electricity
CO2
CO2 capture: In order to cut emissions of this greenhouse gas substantially, it is captured where it is produced (in power generation, for example)
and then injected into suitable geological formations or exhausted fossil fuel deposits.
power plant within the coming decade. The budget for the
project is a billion dollars.
Linde’s Dr. Harald Ranke is already looking forward to early
2006, when companies eligible to trade emissions must report
their CO2 balances. Those emitting more carbon dioxide than
their allotted or acquired rights will incur penalties of 40 euros
per tonne. “Perhaps CO2-free power plants will then gain acceptance even more quickly than we had thought,” he says.
Bernd Müller, a freelance journalist in Esslingen, writes
for scientific and business media, with a special focus on
innovative technologies.
Links for further reading:
www.vattenfall.com
www.europa.eu.int
www.bmwi.de
www.co2sink.org
www.encap.org
www.linde.com
CASTOR
This EU-funded project concerning CO2 capture and storage
in Europe began in February 2004 and is to run for three years.
Participants include numerous energy utilities, industrial
companies and research institutes.
ENCAP
The goals of the ENCAP project include developing “precombustion” technologies with which carbon dioxide
emissions from power plants can be greatly reduced.
Scheduled to run until early 2009, the project claims 33
industrial partners as well as many universities and wellknown research institutes as its participants. The total
budget is 22 million euros. Linde Engineering is currently
involved in two subprojects: “Process and Power Systems”
and “High-Temperature Oxygen Generation for Power
Cycles.”
COORETEC
The COORETEC project (CO2 REduction TEChnologies in fossilfuel power plants) was conceived jointly by businesses,
scientific interests and the German Federal Ministry of
Economics and Labor (BMWA). The aim is to develop technologies needed for highly efficient, profitable coal- and
gas-fired power plants emitting virtually no carbon dioxide.
The project will create the world’s first realistic “road map”
for power plant development. Linde is also taking part in
the project.
20
Fish farming
A fine specimen: The cod is a favorite among seafood lovers.
Linde-technology for fish farming
Elixir of life for Codfish & Co.
Fish is appearing more and more frequently on menus throughout the world. To protect
the oceans from greater overfishing, the number of farming facilities is increasing. But for
salmon and cod to thrive in those fish farms, they need to have plenty of oxygen. Linde
develops technologies for intensive fish farming.
All the world eats fish. People are eating seafood in great quantities, and consumption has been rising for many years. Fishing
operations and farms are running in high gear: While there were
around 100 million tonnes of fish caught and bred in 1990, by
2002 this figure had already increased to more than 130 million
tonnes. And there is no end to fish consumption in sight. According
to estimates by the United Nations’ Food and Agriculture Organization (FAO), demand will rise nearly 40 percent to 180 million
tonnes by the year 2030. In China especially the appetite for fish
is growing at a tremendous rate.
In order to keep pace with market demand, a good one
fourth of all of the fish that end up in the cooking pot today
already comes from farming facilities, which, especially in the
case of freshwater fish, are known as aquacultures. The saltwater variety is also called mariculture. Nearly all of the usual
table fish, such as salmon, perch, cod, turbot, sturgeon, halibut,
catfish, and even shrimp, mussels and seaweed, are now
increasingly being grown in intensive farming facilities. These
fish farms have certain advantages over industrial fishing:
When fishing boats cast their enormous nets over the seabed,
for example, they destroy flora and fauna along the way,
decimating the diversity of species in the oceans. Furthermore,
the nets can trap other ocean-dwellers that have absolutely
no business being there, such as whales, dolphins and seabirds.
Such problems do not arise when fish are raised under controlled
conditions in enclosed breeding tanks. What is more, some
fishing grounds in the oceans have been essentially fished clean
in the past 50 years. For example, cod stocks in the North Sea
have nearly collapsed altogether.
In order for the fish farm residents to thrive as they should,
they need to have sufficient oxygen in the water for respiration
at all times. They require at least 80 percent oxygen saturation in
the water for optimal growth. To achieve this, the concentration
of the life-sustaining gas must be constantly monitored and kept
above the critical threshold. Insufficient oxygen levels cause
poor digestion in the fish, so that they require more food. The
risk of illness also increases. The most important issue for the
aquacultures is thus supplying oxygen to the water. The farmers
do not simply use air for this, but rather add the gas in its pure
form. “The partial pressure of pure oxygen is five times higher
than that of oxygen in air. As a result, it dissolves more easily in
water,” explains Heiko Zacher, Manager of Market Development
Food at Linde Gas. Linde offers complete systems to supply
entire fish farms. “We not only produce oxygen, we develop
the technology for adding oxygen to the water and we supply
the software for optimizing the breeding conditions.”
Differences between fresh and salt water
The technology that is used for oxygenation depends on such
factors as whether salt- or freshwater fish are being raised,
explains Ove Gjelstenli, Customer Segment manager aquaculture
at Linde Gas: Significantly less energy is required to add oxygen
to salt water than fresh. This is because the gas bubbles do not
combine in salt water and thus remain small. As a result, the
oxygen has plenty of time to dissolve in the water. In fresh water
on the other hand, small gas bubbles rapidly combine into larger
ones and rise quickly to the surface. The core oxygenerator is
well established in the market for dissolving of oxygen in water.
Linde Technology January 2006
High demand: According to estimates by the FAO
the world’s appetite for fish may increase to about
180 million tonnes per year.
European frontrunner: The large fish farms of Norway primarily raise salmon.
Water and oxygen are introduced together under pressure in a
conical tank made of fiberglass or steel. The intensive mixing in
the cone brings about the desired oxygenation. This technology
has been available for some time. “But a new development
has enabled us to raise the efficiency by 50 percent,” explains
Karsten Glomset, Product Development Manager at AGA Gas,
Norway.
The company is selling this new technology under the
name ReOx. The system – consisting of the cone oxygenator and
ReOx – is available in a range of sizes, which can oxygenate
from 500 to 2,000 liters of water per minute, depending on the
need. With the added oxygen, the number of fish per tank can
be increased considerably: If the breeder raises the oxygen
saturation in the farm from 90 to 100 percent, for example, fish
production can increase by one third. But because the water
in the enrichment systems is highly oversaturated with oxygen,
it is enough to enrich about 10 to 30 percent of the incoming
water with oxygen in order to achieve the desired 100 percent
oxygen saturation. After oxygen enrichment, the water flows
into the tank via a special instrument known as the Oxy-Stream.
This instrument can be customized as far as dimension and
capacity to fit the specific fish tank. Its specially shaped outlet
nozzles create a circular flow in the tank. In this way, the
oxygenated water is distributed quickly throughout the fishtank
for a homogeneous mixture.
Similar oxygenation systems exist for salt water. AdOx,
a new highly efficient technology which does not require a
cone oxygenator, has been available since August 2005. It can
be operated at a pressure of only 0.2 bar – just one fifth higher
than atmospheric pressure. “These systems thus require very
little energy compared to oxygenation systems for fresh water,”
explains Zacher. AdOx is used for small fish tanks; the alternative
21
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Fish farming
for larger tanks, which is also patented, is called Oxy Process.
As with ReOx, the enrichment device used with AdOx and Oxy
Process is located outside the fish tank. This makes it easy to
monitor its functional capability. Equally important for successful
fish breeding: the systems must also be equipped to handle
emergencies. “If the power fails, for example, the oxygen
concentration in the fish tanks must not fall too far,” explains
Karsten Glomset. Automatic emergency systems are installed for
this purpose: non-electrical solenoid valves open and ensure
that the oxygen feed is maintained in the tanks until the electricity is restored.
Temperature and water quality are crucial
The fish in such breeding farms must also be specially protected
from diseases, which would spread very quickly in the tanks.
For that reason, ozone is often added to the water circulation to
reduce pathogens in fish farms. Besides the oxygen content,
temperature is another important factor that must be constantly
monitored. If the fish pools become too warm, the water loses its
capacity to dissolve gases. Tiny gas bubbles form, as in a glass
of mineral water, but these bubbles are filled with nitrogen.
Nitrogen dissolves easily in water and is released with heat.
The nitrogen gas beads must be removed as quickly as possible,
otherwise they can cause what is known as gas bubble disease.
This condition in fish can cause embolisms in the circulatory
system or blindness. The problem can be prevented by the
addition of pure oxygen.
Up to now, fish farming has been practiced mostly in
so-called open systems, in which water flows into the breeding
facility from open waters and back. But the trend is more toward
closed systems. “In that case, 90 percent of the water remains
in recirculation,” explains Heiko Zacher. Such systems – because
they are almost completely closed off – are more environmentally
friendly than open systems. With support from Linde, a French
fish farming operation set up the first facility in Europe with
closed water circulation in 1992. In order to ensure safety in
such closed facilities, carefully controlled water treatment is a
requirement. Carbon dioxide and ammonia accumulate in the
water of fish farms due to respiration and excretion. With nearly
closed water circulation, these substances must be removed.
This is done either by means of aeration (in the case of carbon
dioxide) or through biological filtration (in the case of ammonia).
Oxygen-rich: To maximize yield in aquacultures, the oxygen concentration must be kept
constant. Linde engineers have developed several different technologies for this.
Linde Technology January 2006
Fast processing: The growing demand for shrimp and other seafood requires an efficient production chain.
Mussels from the wind farm
Seafood no longer has to be bred in fjords and seas. The most
curious location for aquaculture was studied by Dr. Bela Buck of
the Alfred Wegener Institute for Polar and Marine Research in
Bremerhaven, Germany. The researcher suggests in his
dissertation that mussels and a variety of algae known as “sugar
kelp” should be farmed among the towers of the wind power
plants which are planned in the middle of the German Bay.
The institute awarded him the Study Prize for his research. In
the open sea, aquaculture must endure much harsher conditions
than in a protected bay or in a pond. But the settlement frames
arranged in a ring around the wind power plants are able to
withstand the strong current and the waves. One advantage
of this farming method is that some of the harmful parasites that
often afflict mussels have never once appeared in the tested
areas in the open sea.
The country with the highest fish farming production in the
world is China. There, traditional techniques still dominate the
market. Aquatic plants and algae are grown using liquid manure
from hog farming in order to give the carp being bred plenty to
eat. Thirty million tonnes of fish are produced each year using
these methods. That is more than double the amount produced
by the rest of the world combined. Only a small and vanishing
fraction of global fish production takes place in Germany. While
traditional pond farming is losing relevance more and more,
industrial fish farming operations with closed circulation systems
are growing in importance.
technologies, for example to optimize the operation of fish farming facilities,” says Zacher. It is possible to vary the temperature and salt levels within the system to
simulate conditions in the Mediterranean, for example.
The Mediterranean region is already a major market for fish
farming, particularly in Spain, France, Italy, Greece and Turkey.
In the future, South America and Asia could also develop into
interesting markets. According to a study by the International
Food Policy Research Institute, consumption will increase in
developing countries as well, from 62.7 million tonnes in 1997
to 98.6 million tonnes in 2020. So that customers all over the
world can also take advantage of modern fish farming systems,
the research and development center in Ålesund gives seminars.
The connection with customers is crucial, stresses Zacher:
“It is essential to speak the fish farmers’ language. Because
in the end it is their needs to which our systems must adapt.”
Linde fish farming research in Norway
Norway is leading the way in Europe. The large salmon farms in
the fjords make themselves known to consumers each year
at Christmastime when Norwegian salmon fills the supermarket
shelves. Every year some 500,000 tonnes of fish are produced
in this Scandinavian country. With many years of experience
on which to draw, Norwegian fish farming is a highly developed
industry. Linde has thus focused its efforts in this area: Several
hundred Linde systems are already in operation. The fish farming
experts at Linde work mainly with the large, global companies
in the industry. For the past two years, Linde has been operating
a development center for fish farming technology in Ålesund
on the Norwegian coast. “There – in cooperation with partners
from research and industry – we are working to develop new
Sven Titz works as a freelance science journalist in Berlin.
He writes for the Berliner Zeitung, the magazine Astronomie
Heute and other publications.
Links for further reading:
www.linde-gas.com
www.ttzsh.de
www.fona.de
europa.eu.int/comm/fisheries
23
24
Compressor technology
Linde engineers develop ionic compressor
Mobility under high pressure
Mechanical engineer Robert Adler and his team at Linde Gas, Vienna, have realized a
long-time dream of technology: a machine for compressing gases at constant temperature –
isothermal compression. The invention, pursued in vain by engineers for more than 150
years, can revolutionize compressor design. The new technology is finding its first applications in hydrogen and natural gas filling stations.
Buses, cars and even forklift trucks have been running on
natural gas for years. The first hydrogen-driven cars, and a few
forklift trucks, are already rolling down streets and factory aisles
in the U.S.A., Europe and Asia. All these vehicles employ a
gaseous fuel that is unlike gasoline or diesel in the requirements
it imposes on storage and dispensing equipment. “To store the
largest amount of hydrogen in the tank so that the vehicle has
an acceptable range, the fuel must be forced into the tank under
high pressure, at least 450 bar,” explains Linde Gas engineer
Helmut Mayer of Vienna.
Piston compressors are used for pressures between 200
and 1,000 bar. Because these machines have many moving parts,
the guides and bearings have to have good lubrication in order
to prevent wear. But this means that the gas-side space must
be absolutely tight; otherwise, lubricant could get in and contaminate the gas. “Combustion in fuel cells, which offer twice the
energy efficiency of conventional vehicles, demands high-purity
gas without contaminants that would shorten cell life,” says
Robert Adler, head of the Applications Technology Center (ATZ) of
Linde Gas in Vienna. Compressors for hydrogen and natural gas
filling stations therefore cannot be lubricated, and as a result
Innovations wanted: Increasing mobility
calls for unconventional technologies.
One of these is the use of ionic liquids to
compress gaseous fuels.
they experience problems in prolonged operation. “For hydrogen to find commercial use, we must have equipment that can
work for many thousands of hours with no maintenance. Only
then can we build a fueling station capable of delivering the
needed quantity of fuel while running economically.” Such
installations must handle up to 1,500 cubic meters of hydrogen
per day and log around 8,000 service hours – 500 days or so –
without any maintenance. These goals are virtually unattainable
with conventional piston compressors.
Ionic liquids put to use
The team around thermodynamics expert Adler has now come
up with a novel solution to this problem, one that may alter
mechanical design: the ionic compressor. The new device is
named for the ionic liquid media employed by the Linde specialists. These are organic salts with melting points between below
100 degrees Celsius. “Many ionic liquids remain in the liquid
state even at room temperature,” Adler explains. In contrast to
ordinary molecular liquids, ionic liquids consist entirely of particles
with negative and positive electric charges. “They combine
organic and inorganic chemistry, so to speak, and for this reason
Linde Technology January 2006
Ionic liquids have been known for
about 90 years. They are made of salts
that, like table salt, are made up of
particles carrying positive (cations) and
negative (anions) charges. Most salts
have high melting points; the melting
points of ionic liquids are drastically
lowered through the proper choice of
the cations and anions present. The
physical and chemical properties of
ionic liquids vary widely, depending on
the cation/anion combination selected.
These substances have several excellent
properties: They are not volatile or
combustible, they have no measurable
vapor pressure, and they can hold very
high concentrations of a wide range
of materials in solution – from organic
they have new and unusual properties,” Adler says, describing
the qualities of these exotic substances. For example, ionic liquids
have no vapor pressure. This means that molecules do not
evaporate from the liquid, so that the medium cannot mix with
the ambient atmosphere provided it does not reach its decomposition temperature. Because organic molecules are almost
infinite in number, the physical and chemical properties of such
a mixture can be tailored to virtually any requirement; this is
why iconic liquids are also called “designer liquids”. What is
more, the mixtures are not flammable or electrically conductive,
they act to prevent corrosion, they have good lubricating qualities and – above all – they are environmentally safe because
they cannot escape into the atmosphere. The success story, as
told by Adler, begins: “This set of properties gave us an idea that
we began examining closely just about two years ago.”
Linde’s engineers, based in the Third District of Vienna,
have been working for about four years in a collaboration with
DaimlerChrysler AG aimed at developing special compressors
for use in hydrogen fueling stations. “We have now become
the world market leader in hydrogen stations,” says Adler, not
without pride. Indeed, half of the world’s more than 60 fueling
substances such as fats, oils and pharmaceutical products to metals, polymers
and even minerals. The vast number
of possible anion/cation combinations
means that distinct ionic liquids can be
prepared in almost unlimited variety,
so that the medium can be adapted to
nearly any requirement.
stations for gaseous hydrogen have come from the shops of the
think tank in Vienna. “It was with the ionic liquid principle,
though, that we achieved a revolution,” says Adler. The Viennese
team replaced the metal piston of a conventional compressor
with a specially designed, nearly incompressible ionic liquid. In
this way, a “liquid piston” does the work of compression. The
gas in the cylinder is compressed by the up-and-down motion of
the liquid column, similar to the reciprocating motion of an
ordinary piston. Because the ionic liquid does not mix with the
gas, the Linde engineers did not have to include seals and
bearings in their compressor. Adler explains a major potential for
cost savings: “In contrast to a conventional piston compressor,
with some 500 moving parts, we now need only eight.” Maintenance effort is greatly reduced as a result. The only place
where conventional parts appear is in the pump that shifts liquid
back and forth between two cylinders to move the liquid column
up and down. While uncompressed gas is being drawn into
one cylinder, the gas in the other cylinder is compressed by the
“communicating” liquid column.
Remove heat where it is generated
But the Viennese researchers appear to have violated the familiar
principle that says, “Where there is one body, there cannot be a
second at the same time.” The problem with piston compressors
is the piston itself. It is exposed to a very high temperature while
doing the last bit of its compression work, because the gas heats
up greatly when compressed. This heat must be removed. “This
is usually done with heat exchangers located on the outside of
the cylinder. It would be better, of course, to remove the heat
right where it is produced, at the piston face,” says Adler. But a
heat exchanger cannot be located simultaneously at the place
where the piston is doing the work of compression, so this is not
possible. Or it was not until now, for the use of ionic liquids has
enabled the Linde engineers, through a special design, to remove
the heat in the cylinder where it is generated. The result, an
almost isothermal compression process, means that the team of
inventors in Vienna has realized an old dream of the engineer’s
art: physically ideal, nearly 100 percent conversion of energy
supplied into energy of compression. With a classical piston
design, this goal can be achieved – in a purely theoretical way –
only by stacking up an infinite number of infinitely small compression steps.
25
26
Compressor technology
First application: Linde’s novel compression
technology is already being used to fuel natural
gas-powered vehicles.
Communication with a capital C: For Robert
Adler (center), invention is teamwork.
The ionic compressor, however, is real. Since July 2005,
WienEnergie has been using this Linde technology to fuel its natural gas-powered fleet of rental cars. “Our system maintains a
constant gas pressure of 250 bar while delivering 500 cubic meters of natural gas per hour,” says Linde’s lead project engineer
Helmut Mayer. Two other units are currently being put through
field tests as well.
Focus on hydrogen filling stations
But compression based on these novel liquids is not restricted to
natural gas and hydrogen fueling stations. Speaking of possible
uses for the technology, thermodynamic expert Adler paints a
richer picture: “Our systems can replace piston compressors in
many fields, for example the charging of airbags with compressed
gases, the production of ethylene, and diecasting processes.
These are applications where other types, such as screw, membrane and turbine compressors, have been dominant.” Another
huge advantage over many conventional designs will aid the
acceptance of the ionic compressor: “It makes very little noise,”
says Adler. Anyone who has ever stood next to the air compressor
of a jackhammer will take his point immediately. For this reason
if no other, it is not overly optimistic to forecast great success for
the ionic compressor. I
Michael Kömpf, of Regensburg, is a freelance journalist specializing in research and technology. He has written for customer
publications of major industrial firms and edits magazines in the
Corporate Publishing division.
Links for further reading:
www.linde-gas.at
www.uni-oldenburg.de
www.organic-chemistry.org
Linde Technology January 2006
27
Linde researcher Robert Adler on ionic compressors
“The demand is astounding”
The ionic compressor is already attracting great interest in the chemical, automobile and
energy industries. In a conversation with Linde Technology, inventor Robert Adler explains
the concept, applications and potential of this revolutionary technology.
Mr. Adler, in this isothermal compression process you
have discovered what hordes of engineers have long sought
in vain. How did the key idea come to you?
The development of our ionic compressor was a collective
achievement of the team as a whole. The technology is so
complex that no one person could develop it from start to finish.
It required a high level of engineering knowledge and skill
together with a good helping of creativity.
What is special about your idea, then?
First, the use of a “liquid piston” instead of a metal one makes
isothermal compression possible. Second, by using ionic liquids
we prolong the service life of high-pressure compressors – the
time such a device can run without any maintenance at all – by
about a factor of ten.
What advantage does the ionic compressor have over
conventional types?
To begin with, the ionic compressor has far fewer moving parts
than a piston compressor. This means much lower material
costs. And then energy costs are lower than those of conventional processes by as much as 20 percent. There is a great
potential for savings in the service area, too. We anticipate, for
example, that a hydrogen or natural gas filling station equipped
with one of these compressors can operate for nearly two
years without maintenance. This is an important point if you
think about expanded use of natural gas or the commercial use
of hydrogen as fuel for automobiles. What is more, the service
that is still needed is much simpler in nature. These cost factors
will prove vital to worldwide acceptance of a new energy
source like hydrogen.
“Even NASA has
sent us an inquiry.”
Robert Adler
28
Interview
How did you come to think that such a device could
really work?
We have been studying thermodynamic aspects of compressor
design for many years. Our first contact with ionic liquids came
roughly two years ago, and we quickly realized that these could
hold the solution to the wear problem in piston compressors. But
the whole thing works only if the liquid has no vapor pressure,
so that it does not mix with the gas.
How long did you work on development?
About a year and a half passed between the first rough concept
and prototyping. Most of this time went into designing the
optimal properties of the ionic liquid. Collaboration with outside
consultants and Linde Hydraulics was vital. We built the first
full-scale machine early in 2005.
Aren’t ionic liquids rather expensive?
As with most products, it depends on production volume. If one
makes these liquids – such as those used to lubricate dental
drills, for example – on a milliliter scale, yes, this is pretty
expensive. But we have asked our suppliers to shift to largescale production now, and the price looks much friendlier. It is a
good rule that when demand rises, production volume can go
up and prices come down. Besides, the liquid is not consumed in
the compressor. Working on pure gases such as hydrogen, you
can run the compressor with the same liquid over almost the
entire service life. There is virtually no aging.
Profile
Robert Adler (43), a mechanical engineer
specializing in thermodynamics, holds numerous
patents. For four years he has directed the Linde
Gas Applications Technology Center (ATZ) in
Vienna, which currently has a staff of 12. The
center has filed hundreds of patent applications in
this time. Adler built his first internal combustion
engine at the age of 15; by 19 he had developed
a 140-horse-power automotive engine with water
injection. He is now heavily involved with the
ionic compressor.
How many of these machines are in service now?
In the so-called beta phase, exactly three units are being
operated by our customers. They have logged some 3,000
service hours. BMW has a compressor for hydrogen fuel delivery
in Munich, and WienEnergie here in Vienna uses two of the
compressors for natural gas. These devices will have to build up
an aggregate record of 10,000 service hours before we can be
sure we have covered all preventive maintenance practices in
the manual.
What is your next big job?
Our next large machine will deliver about 900 cubic meters
per hour at a pressure in the range of 1000 bar. We are building
this unit for Infraserv Hoechst, which will use it to compress
hydrogen at the Frankfurt-Höchst industrial chemistry park.
Linde Technology January 2006
What kind of reception has your development
had in industry?
We have seen great interest on the part of the automobile and
energy industries. The demand for complete installations is
enormous. As I said, though, we are still in beta testing. Requests
for information have come from Korea, China, New Zealand, really
all over the world. Even NASA has sent us an inquiry. And after
a presentation on our compressor principle, given in London to
representatives of the energy and automaking industries, our
mail server nearly collapsed. Field experience to date has been
quite positive, and we believe we can guarantee 10,000 service
hours with no maintenance. For comparison, piston compressors
need servicing about every 1,200 hours.
What markets do you see as most promising?
In the short term we expect the heaviest demand to arise in
natural gas applications such as fueling stations for forklift truck
fleets. Countries such as Thailand, Iran and the United Arab
Emirates have plans for hundreds of natural gas stations as well.
Commercial applications in the hydrogen economy will follow
soon. Asia, in particular, showing a high level of interest in
hydrogen. Population centers such as Shanghai are having to
put a lot of thought into new propulsion technologies, if only
on environmental grounds.
Isn’t the U.S.A. a leader in the construction of hydrogen
filling stations?
A closer look at the distribution of hydrogen stations reveals
that while the U.S.A. already has twelve stations, the volume
involved is small. In Europe we are building stations somewhat
larger than the American ones; our systems have a capacity of
about 1,500 cubic meters a day, while those in the U.S.A. average
around 5 cubic meters per hour. So fuel station technology in
Europe is quite a bit ahead. Of course, the picture is different in
terms of coverage.
Everybody is concerned with the difficulty of protecting
intellectual property rights when marketing in Asia. Is there
not a danger of infringement?
Well, it is really not the case that you can buy one of our
compressors, take it apart and then copy it. There is a great deal
of know-how that is not apparent. Linde holds all the patents
in the field. While the competition is trying to catch up, we are
naturally not asleep at the steering wheel.
What further applications do you foresee for the ionic
compressor?
This machine will find acceptance wherever a gas is being
compressed and the compressor needs to run for a long time
without maintenance. The ionic compressor is well-suited to
all the gases currently marketed by Linde.
What do your future plans look like?
We are working to get some 20 compressors to market in 2006,
making the jump to full-scale production. Manufacturing will
take place somewhere other than here in Vienna.
The interview was conducted by Michael Kömpf.
29
30
Food-grade gases
Linde Gases extend shelf life of foods
Fresh strawberries instead of
sauerkraut from the barrel
Ready-to-eat, preportioned foods from the cold case are the order of the day. These
products are packaged under an unmodified atmosphere in order to extend their shelf
life. Whether it is broccoli, Emmentaler cheese or turkey breast, each food has to have
its own special blend of gases.
Gas maintains freshness: To keep strawberries from losing
their crispness during the journey from harvest to consumer –
often a long one – they are preserved in a natural way.
Linde Technology January 2006
Thirty years ago, the corner grocery supplied us directly with
fruits and vegetables in season; today, in contrast, a trip to the
supermarket for the week’s shopping has become routine in
almost every modern household. We have long since become
used to fresh strawberries in January – something the corner
grocer could not provide. The best he could do at that time of
year was fresh sauerkraut from the barrel. Today’s menu is
enriched with fresh trout from Canada, turkey breast of Spanish
origin and fruit salad from Israel, and these products sell briskly.
To keep foods from spoiling as bacteria and mold gain the upper
hand, the industry has to employ special protective practices.
Methods of preserving foods have been known for a long
time. Along with drying, acidulation, cooling and freezing, a
new technology is increasingly coming into play: MAP, modified
atmosphere packaging. This involves the packaging of foods
under a special gas atmosphere. If meat is not just kept cold
but also packaged in a special gas mixture instead of air, it not
only looks more appealing but also stays good longer. And
what works for meat also works for other foods. The gases in
the package serve several functions: They inhibit the growth
of bacteria, mold and yeast, prevent fats from oxidizing,
halt discoloration and loss of aroma and vitamins, and ensure
stability in terms of shape and volume.
Chilled food Is the thing
In this way, MAP is right in line with the chilled food trend,
the sale of fresh food products from the refrigerator case. For
producers and retailers, chilled food has the great advantage
of being easy to ship and store. Customers are also glad to buy
more and more preportioned foods. To enable the consumer
to enjoy them without worry, Linde experts have developed a
specialty in the packaging of chilled food. The use of food
gases prevents the growth of microorganisms in the packaging
and thus extends shelf life. Instead of using artificial additives to
keep foods wholesome, Linde gases offer a natural, transparent
means of preservation. Fresh pasta, for example, has a life of
three weeks instead of one, and coffee remains aromatic even
after many months of storage in the original packaging. The
trend toward chilled food boosts the demand for food-grade
gases. These are registered as additives and must be identified
by “E” number on package labels in Europe. The number one
enemy of freshness is oxygen, which speeds up deterioration
and promotes bacterial growth. As early as 1877, Louis Pasteur
observed that Bacillus anthracis, the microorganism that causes
anthrax, can be killed by depriving it of oxygen for respiration
and exposing it instead to carbon dioxide.
Food-industry uses of carbon dioxide include the refrigeration of foods and the carbonation of beverages. This gas is not
ordinarily used by itself in packaging. A typical gas blend for
the packaging of cased sausages consists of 70 percent nitrogen
Protection for foods: Which Linde gas is used in packaging
depends on the food product.
and 30 percent carbon dioxide by volume. The chief goal of
packaging experts is to displace aggressive oxygen from the
packaging before it is sealed. Not only oils and fats but also dry
foods such as potato chips, peanuts, coffee, powdered milk
and white chocolate contain unsaturated fatty acids, which
render them especially sensitive to oxidation and ultimately lead
to rancidity when the products are exposed to light.
Fresh fruit needs to breathe
The nitrogen in the packaging has a supporting function. Carbon
dioxide dissolves very easily in water contained in the product;
it also diffuses through the packaging film five times faster than,
say, oxygen does. As a result, the carbon dioxide level falls
off with time on the shelf; in the worst case, the film becomes
deformed just as it does with vacuum-packed foods. Nitrogen is
therefore included to keep the package volume stable. An
example where this is useful is potato chips. Instead of the film
being snugged around the product on bagging, as it formerly
was, today the bag is actually inflated so that the chips do not
get crushed and broken in shipping. Besides, the inert gas is
nearly insoluble in fat and water. Nitrogen has an extra benefit
for sliced prepared meats, preventing the slices from sticking
together as they commonly do in vacuum packages.
Not all foods have to be protected from oxygen; indeed,
many need it to remain wholesome. Whole and sliced fruits and
31
32
Food-grade gases
vegetables, such as apples and carrots, must be able to go
on breathing inside the package after harvest; otherwise, they
quickly lose their crispness and become wrinkled. Producers
include a mixture of 90 percent nitrogen, five percent carbon
dioxide and five percent oxygen in the packaging for this reason.
For raw meat, the oxygen content in the package can
range up to 80 percent; the balance is carbon dioxide, included
to suppress bacteria that would make the product go off. The
bacteria- and mold-inhibiting action of carbon dioxide normally
does not appear until the concentration rises above 20 percent,
where the gas combines with water at the meat surface to form
carbonic acid, lowering the pH and making it hard for bacteria
to live.
“Purity law” for gases
Tommy Petersson’s team of Linde experts know exactly what
gas blend is right for a given product. “It depends first of all
on the product, specifically the water content and the risk of
microbial contamination in processing,” says Petersson, product
manager Food at Linde Gas. In the BIOGON® family of products,
Linde offers ten standard mixtures that have proven suitable
in many fields. Linde supplies the packaging gas to smaller
customers already blended. Large customers prefer to receive
pure gases, for example by tank shipment in liquefied form; the
proper recipe is then mixed just before the food is packaged.
As in brewing, there is a “Reinheitsgebot” (purity law) for
gases. Petersson explains: “Carbon monoxide, sulfur compounds
and hydrocarbons have no place in food-grade gases. Purity
requirements are especially strict in this area.” The specifications are defined and published in European Union Directive
96/77/EC.
A database created by Linde Gas experts describes hundreds
of MAP product formulations and tells which food is best
packaged with which gas mixture. This is a treasury of practical
experience from which new customers with new products
can also benefit. “Prepared foods as well as fruit salads and
green salads represent the big trend,” says Petersson. These
products combine freshness and sound nutritional value with
convenience in purchasing and keeping. No wonder that this
segment is growing at some ten percent a year. Chilled food
under modified atmosphere has long been established in France
and England, but Germany is taking giant steps to close the
gap. Preportioned, packaged, unseasoned fresh meat – referred
to as “case ready” in the food industry – is actually recording
significant growth rates.
It has to be fresh: Salad greens, sandwiches
and coffee must retain as much as possible of
their aromatic components and vitamins.
Linde Technology January 2006
Because novel prepared foods make new demands on the
packaging gas solutions, Linde works closely with its customers
to devise the optimal gas blend. If a customer needs a gas for a
new product, Linde experts develop and recommend the proper
mixture on the basis of their steadily growing database. But they
do not simply leave the customer to live with their recommendation. On-site tests are done to find out whether the blend
really works. In its network of testing centers for food-industry
applications, Linde studies the potential shelf lives of various
foods under a range of conditions.
Matching food, packaging and gas
The right gas is just half the story, though. Measurements made
by the German Agricultural Society on market-bought
packaged fresh meat have shown that MAP gases in isolated
cases were incorrectly blended and films not properly sealed.
These tests have taught Linde that not only must the gas be
suitable for the food product, but the packaging must also be
suitable for the gas. MAP gases made up of carbon dioxide and
nitrogen can deliver their full effect only if oxygen is permanently
barred from the ambient air. Barrier films passing very little
oxygen are therefore needed. These are composed of multiple
plastic plies with a barrier ply of, for example, EVOH (ethylenevinyl alcohol copolymer). They are, however, more costly than
plain films. Plastic trays are commonly made of polypropylene or
foamed polystyrene.
Packaging machinery is a key link in the chain. Linde therefore collaborates with equipment manufacturers in order to ensure the smooth interplay of food, packaging and gas. Customers
respect know-how and service: Linde holds a 40 percent market
share in Germany and is the world’s number two producer of
MAP gases. Heiko Zacher, manager of the Food Market segment
for Linde Gas, sees major growth potential for his company in
the food industry: “It is one of the most important target groups
for the future.”
33
Keeping of Foods
Fresh fish
Bread
Fresh pasta
Sausages
Hard cheese
Cookies
Typical shelf life
in air
Typical shelf life
with MAPAX®
2-3 days
a few days
1-2 weeks
2-4 days
2-3 weeks
a few weeks
5-8 days
2 weeks
3-4 weeks
2-5 weeks
4-10 weeks
up to a year
Longer shelf life: Linde’s MAPAX® technology keeps foods fresh
much longer.
With Linde’s MAPAX® technology, Broccoli & Co. stay fresh
much longer than if they were packaged with air. The
Linde process offers big advantages even over canning.
While deep-freezing does keep the product fresh longer,
the refrigeration system uses far more energy. What
is more, many products, such as salads, cannot be deepfrozen if they are to be sold fresh.
MAP gases keep food fresh
–– Mapax®
–– Deep-freezing
–– Ambient atmosphere
–– Canning
Degree of freshness
Bernd Müller, a freelance journalist in Esslingen, writes
for scientific and business media, with a special focus on
innovative technologies.
Time
Links for further reading:
www.linde-gas.com
rics.ucdavis.edu
Safety in manufacturing: The quality of
Linde gases is continuously monitored.
34
Container terminals
Containers everywhere: All kinds of goods are transported over the oceans in these steel boxes.
Forklift truck operation in a container port
One TEU to B3-82-00
The container has become a symbol of globalized trade. Ports all over the world have developed
into massive trans-shipment centers for these steel boxes. A single cargo ship can transport
up to 15,000 of these over the world’s oceans. Compared to that, one container handlers seems
rather unimpressive; however, without it world trade would probably come to a grinding halt.
Linde Technology January 2006
Steel boxes as far as the eye can see. They are packed close
together and on top of each other in rows of four or five. These
so-called TEUs (the abbreviation stands for “twenty-feet equivalent unit”) are standard containers with a length of twenty
feet – roughly six meters – with a height of approximately 2.50
meters.
Lined up at the site of the container terminal in Bremerhaven,
they contain all kinds of trade goods destined for transport
throughout the world. Bremerhaven is one of the most important
trans-shipment centers in Germany. It is used to import goods
from the four corners of the world and to export German goods.
Container ships transport practically everything in these rectangular
steel boxes over the oceans, which contain approximately fifteen
35
locations and has become one of the leading terminal operators
on the continent with a turnover of 11.5 million 20-foot standard
containers (as of 2004). The container port Bremerhaven is the
largest of the group in terms of size and quantity. It has 3.45
million TEUs and is growing at a rate of approximately 9% over
the previous year. Experts expect that this trend will continue
to grow. Jörg Kastendiek, Senator for Economic Affairs and Ports
in Bremen, is hoping to set new benchmarks for the current
year: “The site is on course for an annual turnover of four million
TEUs.”
However, this is not the end of this development story.
Globally, container turnover is a growth industry with excellent
prospects. The world’s largest container ports in Hong Kong and
Goods trans-shipment center: The
container terminals of Eurogate in
Bremerhaven are anchorages for
cargo ships from all over the world.
to twenty tonnes of freight: Coffee from South America, machine
tools to the US, steel tubes for Africa or electronics and toys from
the Far East.
German beer, for example, is a hot seller all over the world.
Approximately 14 million hectoliters are exported each year.
And for this, Bremerhaven is the most important gateway to the
world. Well-chilled beer is kept on pallets in storage rooms at the
port. Many parties already have their routing slips, which contain
combinations of numbers and letters, i.e. B3-82-00 (meaningless
to laymen), as well as their port of destination.
“We keep a portion in reserve for future orders,” explains
Sven Grossmann. He is operations manager of the so-called Container Freight Station (CFS) and his responsibility is to ensure that
the busy container terminal runs smoothly. His employees, wearing the orange safety vests, take care of the speedy loading and
unloading of trucks, train cars and overseas containers.
The container freight business is booming worldwide
The CFS is part of Eurogate. This company was founded in 1999
and runs the Bremerhaven facility. It has over nine European
Singapore handle more than 21 million TEUs annually and this
continues to grow. The Chinese are also working to bring Shanghai up to this level. According to a study by IBM Business Consulting Services, the container freight business will grow over the
next decade by eight to ten percent annually.
All over the world, port authorities, administrators and
politicians are making preparations to profit from this promising
business climate. Whether it’s Pusan in Korea, Shanghai or
Salalah in Oman: busy navigation channels are being deepened,
terminals are being expanded and new, high-tech crane equipment is being installed. This will cost billions. Those who don’t
want to make the investment now will have to be satisfied
with a third- or even fourth-rate port given the high-quality
of the competition. Those with ambitious plans will have to
upgrade because the next-generation cargo ships will be truly
massive: Over 400 meters long and almost 60 meters wide,
they can hold up to 15,000 TEU’s with a draft of more than
15 meters. Right now, designers are hard at work at the Korean
shipyards. Order books are completely filled up; there are orders
for new ships well into 2008. Just in the first quarter of 2005
36
Container terminals
alone, 190 ships have been ordered with a total capacity
of 685,000 containers according to the Institute of Shipping
Economics and Logistics (ISL) in Bremen.
And new ships need new ports. To meet these challenges,
investments need to be made on the German North Sea coast
regarding upgrading existing facilities. Many ports are already
at the limits of their capacity. The Dutch consulting company
Dynamar has discovered that terminals start to have problems
when their capacities are used of 75% or more. Taking into
consideration all the upgrade programs in the works, port facilities
will still be able to keep up until about 2011. Then things will
get critical. We have already seen the consequences of these
kinds of bottlenecks in the summer of 2004 in Los Angeles and
Long Beach where from time to time up to 90 ships were waiting
for one spot at the wharf. Even the Kowloon port in Hong Kong
has become cramped: Cargo ships are starting to deliver so
many containers that the dispatch of outgoing goods is slowing
down. Kilometer lines have been forming and ships have only
been able to be loaded with a considerable delay. Worldwide,
the carefully constructed timetables of the large freight shipping
companies are being affected.
Indispensable tool in the container depot: The Linde
C80 can stack up to six empty containers on top of each other.
Its maximum load is 8000 kg. The raised operator’s cabin
and the open mast provide the operator with the necessary
overview. The so-called spreader (instead of the classic forks)
is maneuverable down to the exact millimeter via a joystick.
The 6-liter turbo diesel motor is linked to a three-speed
automatic transmission.
The logistics chain must be reliable
However, unpunctuality causes major financial losses for shipping
companies: Up to $45,000 per day and ship are added to the
operating costs. “Whoever, for example, doesn't make the train
one time in Antwerp, may lose his cargo the next time in Rotterdam,” says Grossmann describing the problems in this highlycontested market. The historic ties that were established
to specific loading stations are long gone due to the trend of
allowing containers to pass directly through from sender to
receiver. For this reason, ports are more interchangeable than
before and are subject to booming competition. Whoever offers
the most attractive conditions and prices, has the best chance
to maintain his position in the world market. “There is a demand
for reliable logistics chains that will function all over the globe,”
according to Eurogate chief Emanuell Schiffer. “Container handlers
such as the reach stacker are an important part of a port’s
logistics chain,” says Jens Uwe Meier, manager of large customers
and equipment for Linde distributor Willenbrock in Bremen.
“Above all, forklift reliability and availability is very important
in this regard,” says Meier. “Most companies operate the reach
stacker as a so-called key vehicle. This means that this individual
equipment is constantly in operation and, therefore, must be
absolutely reliable.” Special Linde hydraulics guarantees this, for
example, because it has very few components, which causes
very little wear thus significantly increasing the lifespan. If any
problems should occur, the Linde Online Diagnostics system will
connect a service technician directly to the forklift controller via
a mobile phone for quick problem-solving. “Even the often-cited
globalization requires lots of technical help,” says Bergmann.
For example, containers from these leviathans of the sea
must be transferred at lightning-speed to smaller feeder ships.
These ships then make deliveries to Baltic Sea ports from Aarhus,
Denmark to St. Petersburg, Russia. Other boxes must be redeployed for transport by air and then transported by rail and
highway. Export goods usually arrive at the port by truck or train,
and are then reloaded into containers in which they will make
their journey over the world’s oceans.
Linde Technology January 2006
Since time is money in the commercial transport business,
reloading must be fast and efficient. Forklift trucks of all kinds
play a key role here. “Starting with comparatively light 1.2 tonne
diesel forklifts to 45 ton container handlers, Linde equipment is
in operation in many European ports,” says Frank Bergmann
from Product Support Heavy Forklifts at Linde Material Handling
in Aschaffenburg. The small and maneuverable Linde models are
excellent for loading and unloading TEUs in the depots because
they can drive directly into the container itself. However,
transporting a fully-loaded steel box to the port site requires a
real heavyweight like the reach stacker. This 76 tonne truck is
currently the heaviest that Linde makes (model C 4545) and was
specially developed for transporting loaded containers. It can
37
the economic handling of empty containers, it makes sense to
use a forklift truck designed for just such a purpose, e.g. the
Linde C80. Fast and maneuverable because it is much lighter
than its big brother, the reach stacker, it can stack up to six empty
containers. In addition, due to its low weight, better maneuverability and high lifting speeds for empty containers, its handling costs per container are lower compared to full-container
handlers. This saves time and money for port operators.
Three dimensional puzzle
Bremerhaven has great hopes for its new CT 4 terminal. It should
be completed by the end of 2008. However, although the
new quay has a length of 1681 meters, this is not enough for
Heavyweight: The Linde reach
stacker C4535 – weighing approx.
76 tonnes – can lift containers up
to 45 tonnes. Even in the second
row, 35 tonnes are no problem.
This power comes from an 11-liter
diesel motor with almost 1700 Nm
of torque. Working conditions
are optimized within the operator’s roomy cabin.
move the full container from the loading site to the so-called
pre-loading zone. From there, large portal cranes lift the TEUs to
the waiting container ships. The reach stacker can easily lift up
to 45 tonnes to great heights. This makes it especially well-suited
for flexible handling of the steel containers throughout the entire
port. And this highly advanced forklift truck can also lift other
loads: Even the loading of complete railcars and/or swap trailers
from trucks to special roll platforms is not a problem.
Forklift trucks as flexible port tools
Bergmann sees a growing market for these powerhouses on four
wheels for container terminals. “Anywhere that containers
are switched, repacked, moved, stacked or just turned around,
the reach stacker is the right tool. It can also be used in isolated
corners of a container depot,” explains Bergmann. It can be
taxied within the tightest space thanks to its smooth steering. Its
high lifting speed and light-touch steering ensures fast turnaround
– a factor that is very important in the transport industry. For
the very huge ocean giants, due to the low water depth. These
ships will be docking in the next decade at the planned German
deep-water port called “Jade-Weser-Port” in Wilhelmshaven.
A maximum of four large container ships with drafts of up to
16.5 meters will be able to be handled simultaneously at the
1725 meter long quay. Planned investment: €900 million. The
annual turnover of the port will initially be approximately 2.7
million TEUs. And because it is located the farthest east between
Le Havre and Hamburg, it should enjoy a leading position with
regard to ocean transit traffic with Scandinavia and Eastern
Europe.
In the meantime, the “London Express” has moored and waits
on its cargo for Baltimore. “The recipient has already transmitted
the required order documentation and reserved a place on the
4000 TEU ship,” says Grossman. The pallets are then taken from
the storage area using Linde forklift trucks to an empty container
that has already been prepared. The container is finally taken
to the pre-loading zone near the berth of the “London Express”
38
Container terminals
using the reach stacker. The exact location on board is decided
by the ship planners at Eurogate. They receive a detailed container
registration list from the shipping company, which lists all
steel boxes that are supposed to go on the cargo ship. Special
containers which contain hazardous goods or refrigerated goods,
for example, are prominently labeled. The same is also true for
containers that deviate from standard dimensions. Normally, the
hold managers of the shipping company determine into which
hatch they disappear. However, there are several ironclad rules
for this three-dimensional puzzle. Heavy containers are placed
on the bottom and lighter containers on the top. Whatever is
unloaded first, is the last on board. Also the stability of the cargo
must, of course, be ensured during swells.
The planning team has the coordinate systems of all ships
saved on their computers. The cross section of the cargo space
can be displayed on the screen with just the press of a button.
Small rectangles symbolize the available space. Letters represent
areas reserved for special applications. Planners search for the
optimal location for each container by moving the virtual container
to the right position using the cursor. Number, client as well as
origin and port of destination can be accessed with just the click
Next generation heavy forklift trucks
Linde introduced a new heavy forklift truck generation at the
world’s largest materials handling equipment trade fair (CeMAT) in
Hanover in October 2005. The new diesel forklift truck of the 359
series has a load range of 10 to 18 tonnes and is equipped with a
unique drive system for this weight class: the Linde hydrostatic
drive. It manages without a gearbox, clutch, differential and drum
brakes. In combination with the electronic “Linde Load Control,”
its double-pedal control enables sensitive and precise load handling. Without shifting and clutching, the 129 kW diesel motor can
accelerate the forklift up to 30 km/h – with or without a load. In
addition, it reduces maintenance costs due to its lack of many wear
parts. The roomy, glass-enclosed operator’s cabin is mechanically
isolated from the motor and drive train compartment via a rubber
bearing. This helps to suppress shocks and vibrations to a large
extent. A deciding competitive advantage is that it has proven itself
in hard continuous use.
of the mouse. Copies of the completed loading plan are sent via
e-mail to the hold management of the shipping company and
the captain of the ship. The container handlers cannot get started
until both have sent their authorization. Once the approval has
been received, the steel boxes on the quay are stacked mirrorinverted to the stowage plan so that they can be quickly stowed
on board in the right order.
Asia’s ports are world class
A so-called “ship to shore” (STS) crane bridge now takes over
and picks one container after the other. A computer helps to
cushion the dangerous oscillation of the container. Special laser
sensors measure the exact position of the container in the hold
making for easy loading. The container to Baltimore is placed
gently and to the exact centimeter into its designated place.
B3-82-00 is the abbreviation for this. B3 stands for the hatch,
82 for the first layer on deck, 00 for the center of the row.
This is how it is noted in the stowage plan whose current
version is sent to the hold management. This way, the shipping
company always knows where each box is stored – even when
the “London Express” is already underway in the Atlantic.
Linde Technology January 2006
Eurogate has a total of 27 high tech container STS in
Bremerhaven. Their cranes have a reach that is sufficient to
load and unload any cargo ship – even those which cannot fit
through the narrow Panama Canal due to their width. An
experienced bridge operator can move up to 40 containers per
hour. These container bridges are manufactured by the Shanghai
Zhenhua Port Machinery Company, the leading international
manufacturer of this type of equipment. The STS weigh up
to 2000 tonnes and measure over 140 meters across and 80
meters high. Their arms can reach over more than 20 rows of
containers.
The largest container ports in the world have long been
Hong Kong and Singapore. These are followed by Shanghai and
Shenzhen in China. And that’s not all, even smaller and mediumsized ports will want to expand in the coming years. Above all,
the Eastern European markets are very appealing to the Chinese.
And this in turn provides opportunities for German ports: The
bulk of the goods delivered in Bremerhaven and Hamburg
are only there on a short stopover. Most will continue on to the
Baltic States, Russia and South Eastern Europe.
For Eurogate, the container business with China alone
amounts to a third of its turnover. However, trade with China
measured in the flow of containers has developed into a rather
one-sided affair: Even when German luxury cars or machine
parts are shipped to Asia from Bremerhaven on a regular basis,
a large portion of the containers going in the direction of China
are often empty. And they are priced accordingly: renting a
container to Europe is up to five times more expensive than
one going in the opposite direction. Nevertheless, the national
economies in East Asia will continue to spur strong growth of
container ports. “The more containers used the more bridges,
cranes and forklift trucks will be required,” says Bergmann.
Claus Spitzer-Ewersmann works as a freelance economics
journalist in Oldenburg. His articles have appeared in
Rheinischen Merkur, Süddeutschen Zeitung and Berliner
Zeitung, among others.
Links for further reading:
www.eurogate.de
www.jadeweserport.de
www.linde-forklifts.com
39
World trade is booming: According to an IBM study, the container cargo
business worldwide will grow eight to ten percent per year over the next
decade.
The world’s largest container ports 2004
turnover in 1000 TEUs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Source: Lloyd’s List, February 2005
Hong Kong
Singapore
Shanghai
Shenzen
Pusan
Kaohsiung
Rotterdam
Los Angeles
Hamburg
Dubai
Antwerp
Long Beach
Port Kelang
Qingdao
New York
Tanjung Pelepas
Ningbo
Tianjin
Laem Chabang
Bremerhaven
China
Singapore
China
China
South Korea
Taiwan
The Netherlands
USA
Germany
VAE
Belgium
USA
Malaysia
China
USA
Malaysia
China
China
Thailand
Germany
21,932
21,310
14,557
13,615
11,430
9710
8270
7321
7003
6429
6064
5780
5244
5140
4478
4020
4006
3814
3624
3450
Asian container boom: The largest trans-shipment centers for these
steel boxes are in the Far East. Around 22 million of these 20-foot standard
containers (TEUs) are loaded annually in Hong Kong, for example.
40
Greenhouse gas
Greenhouses use byproduct CO2 from oil refining
Greenhouse gas from the pipeline
Carbon dioxide makes plants grow. Dutch nurserymen used to fire up gas furnaces –
even in summer – using the exhaust gases to boost the productivity of their greenhouse
operations. In doing so, however, they contributed to heating up the Earth’s climate.
Two inventive scientists have now resolved the dilemma with Linde’s support. A nearby
refinery and an almost-forgotten pipeline aided their project.
Linde Technology January 2006
In September 2005, Queen Beatrix paid a visit to greenhouse
farmer Hans Bunnik. The destination was an agricultural site
outside the gates of Bleiswijk, a little town some 30 kilometers
from Her Majesty’s residence. Bunnik Plants is regarded as one
of the most innovative growing operations in the Netherlands.
It was 1988 when Hans Bunnik and his brothers Frans and Fred
built their first greenhouses to raise exotic greenery such as
umbrella plant, miniature bamboo ‘Monica’ and ficus ‘Natasja’
for sale to Western Europe’s living rooms. Today the company
numbers international retail chains like IKEA, Lidl, Aldi and Albert Heijn among its customers. Its success can be measured by
the numbers: The initial growing area was Bunnik Plants 1, and
the latest one built is Bunnik Plants 6. In botanical glass palaces
covering the area of several football fields, plants are tended
almost completely by automation. A robot maneuvers the pallet
wagons on which the pot plants grow from seedling to finished
product, while a computer controls the application of fertilizer.
A camera identifies which plants are currently passing the
supply station. Human beings can seldom be found among the
innumerable pallets.
41
CO2 transport: This Government pipeline
lay idle more than 20 years before being
converted to carry CO2.
Purmerend
Velsen
Zaanstad
AMSTERDAM
Haarlem
2
-p
ip
el
in
e
Amstelveen
CO
Oil and agriculture in partnership
Queen Beatrix did not come to view an automated greenhouse
but to give her blessing to an intelligent project that combines
economics and ecology in a unique way. Hans Tiemeijer and
Jacob Limbeek had a vision of making business partners of two
important – and indeed opposing – pillars of the Dutch economy,
the oil industry and agriculture. They named their program OCAP
(Organic CO2 for Assimilation by Plants). The two initiators took
a greenhouse gas, CO2, an oil refinery byproduct that used to
be released unused into the atmosphere, and put it to work in
greenhouses. The Linde subsidiary Hoek Loos and the contracting
firm VolkerWessels invested jointly to bring the project to life.
In view of the amounts of CO2 generated daily by power
plants, heating systems and automobile engines, abatement of
this gas is one of the world’s greatest challenges. “In the period
between 2008 and 2012, the Kyoto Protocol requires us to reduce
our consumption of climate-relevant gases by six percent in
comparison with 1990,” says Pieter van Geel, the Dutch Minister
for Residential Construction, Land Use Planning and Environment.
States such as Japan are even exploring the possibility of
protecting the Earth’s atmosphere by sinking CO2 in the oceans.
Many environmental experts believe, however, that the major
impact will be due to energy-conserving technologies. Recent
studies show that CO2 emissions can be reduced as much as
30 percent by the year 2020. “We have the technology to do
Hilversu
Leiden
UTREC
‘s-Gravenhage
Alphen
Zoetermeer
Delft
Schiedam
Vlaardingen
Nieuwegein
Gouda
Capelle
Rotterdam
ZUID-HOLLAND
Spijkenisse
Dordrecht
Scientific agriculture: The plants in
this Bunnik greenhouse need a lot of
carbon dioxide in order to thrive.
U
Oosterhout
42
Greenhouse gas
Royal presence: The new facility was
inaugurated by Queen Beatrix of the
Netherlands together with Dr. Aldo Belloni
(right), board member of Linde AG; Peter
Stocks (second from left), Linde Gas
divisional board member; and Andries de
Jong, member of the managing board of
VolkerWessels Stevin N.V.
this,” says Bernd Brouns, a climate expert at the Wuppertal
Institute for Climate, Environment and Energy. “What is lacking
is the political support.” In this respect the founders of OCAP
have nothing to complain about. Along with the Queen, those
present at the official opening of the Bunnik Plants project
included many prominent political figures such as Minister van
Geel. Bleiswijk lies in a region that is home to the world’s
largest contiguous greenhouse area. The first greenhouses were
simple sheets of glass that growers leaned against walls. Not
until 1900 did modern greenhouse architecture appear, with
internal heating that made it possible to raise cut flowers and
pot plants.
Today the province of South Holland is chock-a-block with
glass roofs. Even if Dutch dike builders have claimed large areas
from the North Sea over the centuries, still land is scarce and
expensive in this most densely populated country of Europe.
Plant growing in the greenhouses is therefore set up on an
industrial basis. Wherever possible, computers manage logistics,
watering and nutrient application. The Dutch agricultural system
is among the most productive in the world, but if it is to remain
so, growers need large amounts of the CO2 that their plants
use for photosynthesis. To increase the level of CO2 and thus
the productivity of their operations, farmers used to light their
natural gas-fired furnaces at regular intervals, conveying the
exhaust gas into the greenhouses where it served as a volatile
fertilizer. “As much as 15 percent of gas consumption was just
for the purpose of obtaining CO2,” says Jacob Limbeek. The
remainder was also used for heating, at least in winter. Thanks
to Limbeek, 33, and Hans Tiemeijer, who died in 2004, this
waste is now coming to an end. It took them eight long years
to convince growers, politicians and industry how easily this
problem could be solved. Many hesitated or backed out, but
when Queen Beatrix visited Bunnik Plants she showed that
Limbeek and Tiemeijer’s efforts had not been in vain.
CO2 from the refinery
It all began in 1997 with an assignment from Energie Delfland,
the utility that supplies large parts of South Holland with
electricity and gas. Limbeek, a physicist with the company, and
his supervisor Tiemeijer were asked to explore areas where
active support could be provided toward reaching the Kyoto
targets. The first glimmer of the OCAP concept came when the
OCAP in Brief
Name:
Owners:
Length of pipeline:
Number of customers (November 2005):
Maximum delivery rate of CO2 by Shell:
Maximum withdrawal rate by greenhouses:
Pressure at head of pipeline:
Natural gas saved:
CO2 emissions saved:
“Organische CO2 voor de Assimilatie van Planten” (Organic CO2 for Assimilation by Plants)
Hoek Loos B.V., Linde subsidiary
VolkerWessels, contracting company (equal shares)
Approx. 85 kilometers (Rotterdam to Amsterdam)
About 400
105 tonnes per hour
160 tonnes per hour
22 bar
95 million cubic meters per year
170,000 tonnes per year
Linde Technology January 2006
43
Planned Greenhouse Gas Reductions
Source: German Ministry of the Environment
Change
2012 relative to 1990, %
Luxembourg
Germany, Denmark
Austria
United Kingdom
Belgium
Italy
Netherlands
–28.0
–21.0
–13.0
–12.5
–7.5
–6.5
–6.0
Change
2012 relative to 1990, %
Finland, France
Sweden
Ireland
Spain
Greece
Portugal
two learned that Shell had just brought its largest European
refinery on-stream in Pernis, west of Rotterdam. In a threestage process, the energy giant refines 400,000 barrels of crude
oil per day into gasoline, heating oil and other petrochemical
products. The key realization was that cracking of heavy hydrocarbon molecules yields carbon dioxide of almost 100 percent
purity as a waste product. In other words, Shell was discharging
into the air the raw material greenhouse operators needed so
urgently. The first two pieces of the puzzle were now in place,
but the two men’s idea did not become feasible until they became
aware of another useful fact: Not far from Pernis was the
head of a pipeline leading across South Holland all the way to
Amsterdam. The special point about the pipeline was that it
had lain idle for more than 20 years. In the 1960s, this pipeline
had nourished high hopes.
In building it, the city of Amsterdam and the Dutch government sought to promote business in the western harbor of the
metropolis on the Amstel. The port was already too small for
giant oil tankers, but an American company nevertheless began
operating a refinery because crude could be obtained via the
pipeline from the port of Rotterdam, some 80 kilometers away.
Shutdown came after only two years, however. The facility was
closed, and in the mid-1980s the pipeline was also taken out
of service.
Visions demand risk-taking
But it was still there. What could be more obvious than to restore
the pipes to use, now carrying CO2, and use them to connect
greenhouses directly to the Shell refinery? But support from
Limbeek and Tiemeijer’s employer ceased when Energie Delfland
was acquired by its competitor Eneco in 2000. The new owner
had no further interest in the research and canceled the project.
The two scientists thereupon started their own company, named
it “Syens,” and went looking for investors. They first tried their
luck with venture capitalists. No success. Then they hit on the
construction company VolkerWessels, which did show interest.
“We get people coming to us with the craziest ideas,” says board
member Andries de Jong of the first meeting with the two
0.0
4.0
13.0
15.0
25.0
27.0
Distribution of burden among EU
countries: The European Union has
committed itself to an 8 percent
reduction in greenhouse gases.
Burdens are distributed unequally
from country to country, with
Luxembourg required to attain the
largest reduction and Portugal
allowed to record the greatest
increase.
visionaries. “This idea was also something out of the ordinary –
but it was well thought out.”
Don Huberts, General Manager of Linde AG’s Dutch subsidiary
Hoek Loos, also found the concept exciting. As a gas utility
specialist, he could easily see joining with VolkerWessels to get
OCAP moving. The challenge lay in the atypical business model
on which Hoek Loos would have to build. Ordinarily the company
makes contracts running for at least 15 years with just a few
customers that consume large amounts of gas. Everything was
different in OCAP, for the potential clientele was made up of
hundreds of greenhouse operators looking for much shorter
contract periods. “It takes vision to embark on such a project
and bear the risk,” Huberts says as he looks back to late summer
2004. “One of the key reasons we made the decision to go
ahead was our desire to dedicate ourselves, as a company, to
socially important tasks.” That broke the ice. Hoek Loos and
VolkerWessels created the OCAP joint venture, putting up equal
shares of the total startup capital of 100 million euro. The
financial cushion was now in place, but the project itself was
just beginning.
Even though the initiators of OCAP could not be sure of
every detail at the time, they started out by persuading Shell to
connect the Pernis refinery to the pipeline. The gap to be
bridged was less than a kilometer. “The entire project also made
a very good fit with Shell’s sustainability policy,” explains Luc
Spitholt, chief technologist at Pernis. “That is why we were
prepared to accept more risk than usual.” Obtaining government
approvals for the pipeline proved more difficult. It was not just
the Dutch central government and the city of Amsterdam, which
jointly owned the former crude oil pipeline, that had to go along
with the new use; the provinces of South Holland and local
authorities in Rotterdam and Rijnmond, as well as a number of
communes lying along the route, also had their say in the
decision. The end of 2004 finally saw all the needed documents
collected. “This project has taught us one thing,” says Jan
Franssen, the Royal Commissioner for South Holland. “A sound
social and environmental policy requires business and government to travel new paths.”
44
Greenhouse gas
Saving a third on fertilizer costs
From that point, everything went quite quickly. VolkerWessels
took care of cleaning up the pipelines and closing gaps at the
supplier and customer ends. In the meantime, a team from Hoek
Loos built the compressor station on Shell land. Arriving at the
station shortly after exiting the Shell refinery at atmospheric
pressure, CO2 is compressed by a factor of 22 in three stages.
The system feeds a total of up to 105 tonnes per hour into the
pipeline, but as much as 160 tonnes per hour can be taken
from it at peak times. While the greenhouses need CO2 in the
daytime when the sun is shining, the refinery produces the gas
around the clock, so that the pipeline gets overfilled at night.
This “breathing” ensures that there is additional gas to spare.
The biggest challenge was now the tight schedule. The
OCAP venture naturally wanted to achieve a proof of concept in
the summertime, when the greenhouses generate especially
high CO2 demand. And in fact that is what happened, even
though ground was not broken until March 2005. “We got the
pipeline operating within four months,” says a contented Piet
van Heteren, OCAP project manager for Hoek Loos.
Greenhouse operators appreciated the ambitious nature of
the effort. Preliminary contracts were taken by 400, that is, around
60 percent of all possible candidates. Why? “I am now saving
about a third on the cost of CO2 fertilization,” explains OCAP
customer Hans Bunnik.
In all, it is estimated that 95 million cubic meters of natural
gas can be saved by getting CO2 directly from Shell. This synergy,
which transforms a waste product into a raw material, will mean
170,000 tonnes less carbon dioxide released into the atmosphere
every year. “And we can accomplish much more in the future,”
believes Limbeek, who continued marketing the OCAP concept
by himself after Tiemeijer’s death. “The region around Aalsmeer,
south of Amsterdam, also has many greenhouses – and the
pipeline runs right past that area.”
Frank Grünberg specializes in stories about technology at
the interface of business and science. A resident of Wuppertal,
he writes for technical publications and customer relations
magazines.
Links for further reading:
www.ocap.nl
www.bunnikplants.nl
www.hoekloos.nl
The Kyoto Protocol
The more than 50 states that have so far
signed the Kyoto Protocol have expressed
their intention of reducing greenhouse gas
emissions over the long term. In the period
from 2008 to 2012, emissions are to drop
by at least five percent below the 1990 level.
The gases in question are held responsible for
the “greenhouse effect” because they alter
the properties of the Earth’s atmosphere,
which, like a greenhouse, protects the planet
from the icy cold of outer space. Short-wavelength energy from the sun passes right
through these gases. The long-wavelength
radiation reflected by the earth is retained by
them, heating the atmosphere. Early signals
of climatic change can already be detected
as sea levels rise, deserts extend their reach
and hurricanes increase in number. The Kyoto
Protocol identifies the following gases as
the major sources of danger: methane (CH4),
dinitrogen oxide (N2O), partly halogenated
fluorocarbons (CFCs), perfluorocarbons, sulfur
hexafluoride (SF6) and carbon dioxide (CO2)
produced by the burning of such fossil fuels
as coal, oil and natural gas.
Image credits: Adam Opel GmbH, OSV, p. 26 top | Affeldt, Joachim p. 12 | Bunnik Plants p. 40 | Corbis p. 20, 21 bottom,
23 top, 24, 25, 34 | Dockwise p. 13 left | Eurogate p. 35, 39 | RWE p. 14, 15, 16 | Shell p. 13 right | Statoil p. 7, 9, 10,
11 | Vattenfall Europe AG p. 19 | Zefa p. 6, 30 | The Linde Group is in possession of all other photographs.
ISSN-1612-2232
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