Linde Technology 2/2004

Transcription

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Reports on Science and Technology December 2004
Linde Technology
LeadIng.
Oxygen Usage in Steel Production
Forklift Truck with Fuel Cell
Biotechnology for Innovative Medications
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Editorial
Dear Readers,
The boom in the Chinese economy has led to a major world-wide comeback in the steel sector. Many steel mills are
today producing at full capacity, and, after years of stagnation, prices have perceptibly started to rise again since 2003.
At the same time, however, the costs of raw materials and energy have increased substantially, and in many traditional
export countries the wave of consolidations continues unchecked. In this sensitive environment, efficient plants and
production processes are decisive factors when it comes to competitiveness.
In this situation, a solution developed by Linde can make a contribution which will guarantee not only substantial
savings in energy consumption but also higher throughput. Thanks to the use of pure oxygen in flameless combustion,
the REBOX® Technology also reduces the nitrous oxide and carbon dioxide emissions from foundries and rolling mills.
With these and other topics, ranging from bio-technology to plastics processing, the December issue of Linde Technology
provides a fascinating insight into industrial innovation potential, one of the most important factors in international
competitiveness. We invite you, with this issue, to find out more about these technologies of the future, and we wish
you an inspiring read.
Stefan Metz
Head of Technical Press
Linde AG
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Cover photograph
Before stainless steel is wound into
coils, it is heated twice to 1200°C.
With REBOX®, Linde has developed
a technology with which the energy
required for heating up the steel
can be reduced by half.
Imprint
Publisher: Linde AG, Wiesbaden www.linde.com
Editorial Staff: Editor-in-Chief: Stefan Metz, Linde AG;
Science&Media, Büro für Wissenschafts- und
Technikkommunikation, Munich
Layout, lithography and production: D+K Horst Repschläger GmbH,
Wiesbaden
Translation: eurocom Translation Services GmbH, Vienna
Printing: HMS Druckhaus GmbH, Dreieich
Inquiries and orders: 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 – December 2004
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Content
4_ Saving energy in steel production:
3
20_ Environmentally-friendly material transport:
28_ Innovations in the pharmaceutical industry:
Crude steel is efficiently heated with
Forklifts operating with hydrogen produce no
New concepts are used in the planning of
pure oxygen.
exhaust gases.
biotechnology plants.
4_
New Technique Boosts Production, Saves Energy
and Reduces Emissions
Efficient Steel Processing thanks to REBOX®
Dr. Joachim von Schéele and Per Vesterberg
14_ Industrial Gases Assist in Injection Molding
Nitrogen and Carbon Dioxide Fill any Shape
Andreas Praller
20_ Forklifts with Fuel Cells
The Only Byproduct is Water Vapor
Norbert Pfeiffer
28_ New Trends in Pharmaceutical Industry
Future Market: Biotechnology
Dr. Hans-Jürgen Maaß and Dr. Karin Bronnenmeier
38_ First Application of a New Process for Producing
Linear Alpha-Olefins
Base Stock for Plastics and Detergents
Heinz V. Bölt and Dr. Peter M. Fritz
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Dr. Joachim von Schéele and Per Vesterberg
New Technique Boosts Production, Saves Energy and Reduces Emissions
Efficient Steel Processing thanks
to REBOX®
On the average, steel is reheated twice after casting so that it can be rolled or forged. This
involves significant quantities of heat. The Linde REBOX® oxyfuel solutions enables significant quantities of fuel to be saved by the optimum use of oxygen. At the same time, the
generation of environmentally harmful carbon dioxide and nitrogen oxides are minimized
and production capacity rises significantly.
In 2004 steel industry output will exceed a billion tons and in
doing so will achieve a production volume far greater than ever
produced in the history of the industry. After casting, the steel
will be moved to other areas such as rolling mills or forge shops
for further processing. The steel then has to be heated until it
reaches the temperature needed for these processes; this temperature often needs to be in the region of 1,200°C before the
steel can be rolled, forged or annealed. Thus every ton of steel
which is cast is re-heated on the average twice while it is on its
way to becoming a finished product, with the result that a total
of over two billion tons will pass through re-heat and annealing
furnaces.
The Linde REBOX® oxyfuel solutions can significantly reduce
the high energy consumption involved in the reheating of steel.
In this process oxygen is mixed with any liquid or gaseous fuel in
such a way that the oxygen and the fuel can combine with each
other without any restrictions. This process not only optimizes
the combustion process and the use of the fuel, but the nitrogen
oxide emissions are reduced at the same time. Additionally, it
allows for a much higher production in the furnace. (Figure 1).
Oxygen in steel production
Industrial grade oxygen has been used in very many areas of
steel production for over 50 years. It is used initially in the converter and also in a range of different melting processes, (e.g. in
the electric arc furnace). The blast of a blast furnace is enriched
with oxygen so that the quantity of coke used for reduction of
the iron ore can be reduced. Oxygen also ensures more efficient
combustion in the preheating of a range of vessels.
In the past no or very little oxygen was used in the processes which follow the casting of the liquid steel from the steelmaking furnace. Reheat and annealing furnaces were heated by
air-fuel burners. The burners were later equipped with preheaters
for the air which used the heat from the furnace flue gases.
Prompted by rapidly rising fuel prices in the 1970s, the first
thoughts were given at that time to ways of reducing fuel consumption in reheat and annealing furnaces. This laid the foundation for a development which led to the use of the REBOX®
oxyfuel solutions in rolling mills and forge shops. In the middle
of the 1980s Linde began to equip the first furnaces with
oxygen enrichment systems. These systems increased the oxygen
content of the combustion air to 23 or 24%. The results were
encouraging: the fuel consumption reduced and the output (in
terms of tons per hour) increased. In the REBOX® oxyfuel
solutions, Linde since 1990 uses industrial grade oxygen. This
often produces fuel savings of over 50% and halves the emission
of nitrogen oxides (NOx). The impact on the production capacity
could be an increase by up to 50%.
Avoiding the nitrogen ballast
Only three things are needed to start and maintain combustion:
fuel, oxygen and sufficient energy for the combustion. The combustion is most effective when the fuel and the oxygen can combine with each other without restriction. This is exactly what
happens with the oxyfuel combustion process in which any liquid
or gaseous fuel is used and is mixed with industrial grade oxygen
instead of air.
In practical heating applications, the heat transfer must also
be taken into consideration. If, for example, pure oxygen is mixed
with 78% nitrogen and 1% argon (the proportions to be found
in the air we breathe), we will neither get optimum conditions
for combustion nor for heat transfer. An additional drawback is
that the nitrogen is also heated in the combustion process. If the
energy transmitted to the nitrogen is not to be lost and therefore
the fuel wasted, it must be recovered by costly processes, e.g.,
recuperators or renerative solutions.
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Linde Technology December 2004
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Figure 1: Never before in history the world’s
steel production has been higher: Over one
billion tons of steel were produced in 2004.
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New technique boosts production, saves energy and reduces emissions
Figure 2: The development of typical customer requirements and solutions to them provided by Linde technology.
Driver
Increasing fuel
costs
Need for more
capacity
Capacity and
flexibility
Lower NOx
emissions
More capacity
but no physical
space
Ultra low NOx
emissions
1983
1988
1990
1995
1999
2002
Oxygen
enrichment
Oxyfuel boosting
Full oxyfuel
Staged
combustion
Direct Flame
Impingement
(DFI)
Flameless
combustion
Technology/Solution
The replacement of air by oxygen results in a large number
of alterations to the combustion and heat transfer processes:
–– Increased combustion efficiency
–– Reduction in the quantities of gas conveyed to and
away from the process
–– Increase in the partial pressure through the formation
of triatomic gases (H2O and CO2)
These three processes have a significant effect on the furnace
and the heating conditions, potentially reducing operating costs.
The most important advantages arising from the use of the
REBOX® oxyfuel solutions in reheating and annealing are:
–– increased production efficiency
(in tons of steel heated per hour)
–– reduced fuel consumption
–– the possibility of using fuels with low calorific value
which are available on site
–– reduced CO2 emissions
–– reduced NOx emissions
–– verbesserte Zundereigenschaften
–– improved scaling (less quantity and better quality)
–– no reduction in combustion efficiency and heat transfer
during the course of operating periods
–– improved furnace atmosphere control
–– low capital cost
–– simple to retro-fit and low maintenance
15 years experience with oxyfuel
For the last 15 years Linde has been a pioneer in the introduction
of oxyfuel combustion in rolling mills and forge shops. Everything
started in 1990 with the conversion of a soaking pit furnace at
the US bearing steel manufacturer Timken. Since that time Linde
has fitted oxyfuel technology to almost 90 reheat and annealing
furnaces. The range of solutions was grouped together in a product portfolio named REBOX® oxyfuel-based solutions.
The central factor still driving the development is a comprehensive understanding of the customer’s processes and the challenges facing the steel industry. Figure 2 shows some of the customer’s typical requirements and the range of technological
solutions developed by Linde to overcome them.
An investment which pays dividends
The use of the oxyfuel process allows furnaces to be operated at
higher speeds than with traditional air-fuel process. Admittedly,
the conditions have to be more precisely controlled: furnace
pressure and oxygen and fuel flows must be precisely maintained if the burner system is to provide the optimum performance.
This is also important of course if an air-fuel system is to provide
optimal performance but with the oxyfuel system this is an even
more critical factor.
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Figure 3: At Ovako Steel, a leading Swedish steel manufacturer, ingots are heated to 1,200°C in oxyfuel converted soaking pit furnaces prior
to downstream rolling operations.
Up to the present time Ovako Steel, a leading Swedish steel
company, has modified 75% of its furnaces to operate solely
using the oxyfuel system (figure 3). The first solution of this kind
was installed in 1994 and in the meantime a total of 42 furnaces
have been modified.
Cost reduction potential of REBOX®
Steel producers have many different reasons for installing
REBOX® solutions for reheating and annealing. Rising fuel costs
play an ever increasing role today. In addition, the subject of CO2
emissions is increasing in significance in Europe and presents a
further argument for conversion to the oxyfuel process. In some
cases over 70% of the CO2 emissions of scrap-based steel producers come from reheat furnaces. Increasingly tough legislation on
nitrogen oxide (NOx) emissions acts as a further stimulus to the
development of new solutions. Other important factors linked
to increased production also play a part. Many companies are
seeking to increase their output, others want to maintain production volumes but from a reduced number of furnaces or plan
to concentrate production at fewer locations. All are measures
aimed at improving the use of capital employed and reducing
maintenance and personnel costs.
As a generalization it is true to say that the steel industry
is currently short of capital for investment purposes. REBOX®
solutions recognize this problem as they allow the capacity
of existing plants to be increased without the need to extend
exhaust gas cleaning for reheat and annealing furnaces.
In some cases the improved heating produced by oxyfuel
combustion have made a reduction in the number of shifts
worked on rolling mills, annealing furnaces and in forge shops
possible, thus reducing personnel costs which play an important
role in production everywhere (figure 4).
Cost reductions are also possible at the same time as quality
improvements. The Nyby works of Outokumpu Stainless was able
to dispense with several finishing processes as a result of reduced
scale formation, improved scale properties and enhanced surface
quality of the steel heated by the oxyfuel process. Nyby’s Sten
Ljungars stated that although the objective was only increased
output, the introduction of the oxyfuel process also allowed the
company to cut the number of process steps and so reduce costs.
The heating time, as well as the temperature and the quality
of the steel, is an important factor in scale formation. The use of
the oxyfuel process allows the heating time to be significantly
reduced.
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Figure 4: As a result of its extensive experience of oxyfuel applications, Outokumpu Stainless, Sweden, specified that this new roller hearth furnace
at its Degerfors works was to be equipped with oxyfuel technology.
Figure 5: North American Forgemasters, USA,
Figure 6: Flameless oxyfuel maintains a lower and more uniform temperature
achieved a 50% reduction of fuel consumption
than a conventional oxyfuel flame. Temperature peaks cannot be seen either.
and NOx emission for its 6 box type furnaces.
Source: Royal Institute of Technology, Sweden
Temperature in °C
1500
1300
1100
900
0
500
1000
Oxyfuel
Flameless oxyfuel
Regenerative air-fuel
Regenerative air-fuel (O2-enriched)
Cold air
1500
2000
2500
Distance from burner face in mm
Furnace temperature
Furnace temperature-Cold air
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Examples of the use of the oxyfuel process
There is no shortage of examples of how customers have benefited from the introduction of REBOX® solutions:
–– The process is used at Böhler-Uddeholm in Sweden on car
bottom furnaces used for heating prior to forging. The benefits
in this case were a reduction in the fuel consumption of over
50% and reduced heating times of between 25 and 50%.
Further benefits were also improvements in the scale properties and in the surface quality.
–– The box furnaces at North American Forgemasters in the USA
were all converted to the oxyfuel process (figure 5). The
objective of reducing fuel consumption and NOx emissions by
over 50% was achieved in both cases.
–– A completely different solution was found for a plant at Germany’s Buderus. What has come to be known as “oxyfuel
boosting” was installed in a pusher furnace. Buderus was
looking for a modest increase in output. The solution was to
install four oxyfuel burners to boost the existing unmodified
air-fuel system. After the installation of the oxyfuel burners
furnace output increased by about 10% and fuel consumption
dropped by the same figure.
Invisible flames for visible results
A recent development of the Linde REBOX® portfolio of solutions
has been the installation in furnaces of what is called flameless
combustion. This is a technology (known to science as volume
combustion) in which the flames are diluted by flue gases and are
therefore almost invisible. This dispersion results in a lower flame
temperature, which produces significantly less NOx (figures 6
and 7). The dispersed flame still contains the same amount of
energy but is spread over a wider area, thus producing more uniform heating.
Although only oxygen is used in the conventional oxyfuel
process, nitrogen oxides are produced as a result of the high
flame temperature and the ingress air. On the other hand, NOx
production in flameless oxyfuel combustion can be reduced to a
minimum and, in the case of stable furnace conditions, to less
than 25 mg/MJ (figure 8).
Flameless combustion has such major advantages that this
process is likely to be installed in most applications. The advantages of conventional oxyfuel combustion are combined with
those of flameless combustion to produce improved heating and
reduced NOx emissions. The latter advantage is normally important in the case of large, continuously operating furnaces but is
also relevant to other heating processes, for example the preheating of ladles.
Rapid heating where space is restricted
Direct flame impingement (DFI) in which the oxyfuel flame
impinges directly on the metal passing through the flame has
proved to be the most effective process for improving heat transfer (measured in kW/m2). It uses the same principle as is used in
the preheating of metal surfaces with the welding torch prior to
the actual welding process.
The first plant of this type built by Linde provides a very
good example. The customer’s objective was to increase the production capacity of a catenary furnace already fitted with oxyfuel
equipment by 50% but without increasing the length of the furnace. To meet this requirement a compact unit was developed
and fitted to the furnace entrance. The DFI unit consisted of 4
cassettes, each of which was equipped with 30 oxyfuel burners
giving a total of 120 small burners with a total output of 4 MW.
This example demonstrates that the DFI process can be used for a
broad range of applications and heating types and not just for
strip steel.
Figure 9 shows the increase in production capacity at this
customer generated by three different generations of oxyfuelbased solutions. Initial oxygen enrichment was followed by complete conversion to the oxyfuel process and finally by the installation of the DFI process to increase production capacity once
again.
The third revolution
Since 1990 Linde has pioneered the introduction of the oxyfuel
process in rolling miles and forge shops,and installed oxyfuel
solutions in almost 90 reheat and annealing furnaces. In other
words, REBOX® oxyfuel-based solutions have “redefined reheating”. This particularly applies to the new flameless oxyfuel
process which achieves excellent reheat conditions and low
NOx emissions even in large, continuously operating furnaces.
An interesting feature of oxyfuel combustion is that it allows
the use of low-grade fuels. Thus, fuels with a low calorific value
can be beneficially combusted with oxygen and still maintain a
reasonably high flame temperature. There are many examples of
such fuels, for instance flue-gases found in iron and steel production, for example from blast furnaces and converters. Even these
fuels can be used with the oxyfuel process as a substitute for
natural gas in steel reheating operations and with the additional
advantage of lowering total CO2 emissions.
If we look into the future we can justifiably say that the use
of the oxyfuel process has only just begun. The more it is known,
the greater will be the interest in its application. It is often said
that steel production went through two technical revolutions
during the 20th century – oxygen converter steelmaking and
continuous casting. Without these two innovations the world’s
steel production would probably have been less than half its
present level.
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Figure 7: Flameless oxyfuel combustion provides lower
and improved temperature distribution. Note that the
furnace temperature is 1,200°C.
Source: Royal Institute of Technology, Sweden
[°C]
1400
1200
4000
1000
3000
800
[mm]
2000
600
500
600
Figure 8: Emissions of NOx from oxyfuel combustion are
NOx-mg/MJ
comparable to those from regenerative airfuel burners,
300
1000
0
-500
[mm]
700
0
800
900
1000
1100
1200
1300
1400
1500
1600
Burners at 200 kW . O2 from combustion = 2.5-3.5%
whereas flameless oxyfuel is almost insensitive to air
ingress into the furnace.
Source: Royal Institute of Technology, Sweden.
Oxyfuel
200
100
Regenerative air-fuel (21% oxygen)
flameless Oxyfuel
Regenerative air-fuel (29% oxygen)
0
0
The third revolution appears to be of the same magnitude. It
consists of the use of oxyfuel combustion in reheat and annealing
furnaces. Sweden is the starting point for the third revolution
as it is here that oxyfuel combustion is most widely used. At the
time of writing half of all the country’s reheat furnaces have
been converted to this process. It is interesting to note that in
oxyfuel combustion the use of oxygen per ton of steel is at about
the same level as oxygen used per ton of hot metal in blast furnaces or per ton of steel produced in converters.
3
6
9
12
Oxygen concentration in chimney
Abstract
In Linde’s REBOX® oxyfuel system, oxygen is combined with any
fuel in the operation of reheat or annealing furnaces used in
steel production. It often enables fuel savings of over 50% to be
achieved at the same time as reducing the emission of carbon
dioxide and nitrogen oxides by a half. In the latest developments
of REBOX®, using flameless combustion, the nitrogen oxides in
the flue gas can be reduced even further. Moreover it allows for
increasing the production capacity by up to 50%. Thus the
REBOX® oxyfuel system has the potential of revolutionizing steel
production.
Internet
Further information: www.linde-gas.com/rebox
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Production capacity (tons/hour)
35
30
25
20
15
10
5
0
Airfuel
Oxygen
enrichment
Oxyfuel
Oxyfuel + DFI
Figure 9: Capacity increase in a catenary furnace at Outokumpu Stainless Nyby works due to Oxyfuel application, from oxygen
enrichment to full oxyfuel conversion of the furnace and finally DFI (Direct Flame Impingement). The photograph shows the
compact DFI unit of 4 MW, which boosts throughput capacity by 50%.
The Authors
Dr. Joachim von Schéele
Dr. Joachim von Schéele graduated in Process Metallurgy and
Business Administration and received a Ph.D. in Metallurgical
Production Technology from the Royal Institute of Technology
in Stockholm, Sweden. He joined the Gas Division of Linde AG
in 2000 after 8 years of steel industry experience, where he
worked as consultant, research manager and business unit
manager. He is responsible for the customer segment Steel
Industry, Foundries and Recycling.
Per Vesterberg
Per Vesterberg graduated in Mechanical Engineering from the University of Linköping, Sweden. He
got several years of technical industry experience,
e.g. at ABB, working as sales and marketing
manager. He joined the Gas Division of Linde AG
in 2003 where he works as product manager for
Rolling Mills and Forge Shops in the customer
segment Steel Industry, Foundries and Recycling.
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Outokumpu Stainless adopts oxyfuel
to boost production
An early adopter of the technology was Outokumpu Stainless. In
1992 began the journey to convert furnaces to all oxyfuel operation; the new technology was then installed at a comparatively
large soaking pit furnace at its Degerfors plant in Sweden. This
plant is an excellent showpiece for understanding the development of oxyfuel technology. By 1995, the number of pit furnaces
at Degerfors using oxyfuel had reached 8, and 2 box furnaces for
batch annealing were also equipped in the same way. Two other
larger oxyfuel installations followed: a new roller hearth furnace
in 1998 and the conversion of a walking beam furnace in 2003.
The latter employs flameless oxyfuel technology.
Among the benefits obtained from operating these furnaces
with oxyfuel combustion are the short throughput time, which
increases production capacity, and low fuel consumption and
reduced environmental impact, such as emissions of CO2 and NOX.
Low investment costs, with easy retrofits in existing furnaces and
low maintenance activities have further strengthened the application of oxyfuel combustion within Outokumpu Stainless.
“Growing through introducing new technology has been an
exciting journey”, says Sten Ljungars, Technical Manager at
Outokumpu Stainless, Coil Products Nyby. “Of course it has been
challenging, but by continuously implementing new oxyfuel
technologies we have achieved excellent results, strongly
supporting our vision ‘Best in Stainless’”. It is actually possible
today to find four generations of REBOX® solutions in operation
at Outokumpu Stainless in Sweden:
–– The batch annealing furnaces using conventional
water-cooled burners (1995)
–– The roller hearth furnace with ceramic burners with staged
combustion (1998)
–– A catenary furnace with Direct Flame Impingement,
DFI (2002)
–– The walking beam furnace with flameless oxyfuel technology
(2003)
Every 50th ingot is lost!
At elevated temperatures there is always a certain oxidation of
the material being heated, in reheating referred to as scale formation. The scale formation is typically around 1-3%, which
implies that every 50th ingot disappears into oxides, thus the
large interest in minimizing and controlling scale formation.
A certain scale is however desired since it removes surface
impurities and faults prior to down stream processing in rolling or
forging operations. It is also important to have the right scale
properties in order to easily remove them. The amount of scale
formation depends on the furnace atmosphere, the temperature
and the residence time in the furnace.
In oxyfuel converted furnaces the oxygen is used in the
combustion process and the furnace atmosphere is controlled.
This is important since the content of oxygen in the furnace flue
gases affects the level of oxidation. The diagram indicates that
the time factor is an important factor in scale formation. The
efficient heating properties of oxyfuel reduce the time exposure
in the furnace to lower the level of scale formation that will be
possible. Experience and research from 85 oxyfuel converted
furnaces shows that scale formation is reduced with improved
scale removal properties.
The scale formation increases with exposure time. Therefore
it can be reduced by using Oxyfuel technology.
% of scale formation
1.200 °C
Time
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Revolutions in Steel-making
The first revolution in modern steel-making began over 50 years
ago with the oxygen steel-making converter, also referred to as
Basic Oxygen Furnace (BOF). In this furnace the liquid iron from
the blast furnace together with scrap is converted into liquid
steel by the use of oxygen, which removes carbon and other
unwanted elements and impurities.The benefits of using oxygen
in steel-making have been recognised since 1856 when Sir
Henry Bessemer referred to the possibilities of oxygen in his
patent for the Bessemer process. Unfortunately, large volumes of
oxygen could not be produced at that time. Therefore, Bessemer
had to use air instead of oxygen. Carl von Linde changed all this
in the early 1900s with his invention of large-scale oxygen production. It was not until after the Second World War, however,
that large volumes of oxygen began to be used in steel-making,
now in the BOF process which increased the production rate by
five times or more. Additionally, the use of oxygen in iron-making
is now commonplace with the extensive use in blast furnaces.
The second revolution in steel making is definitely the continuous casting process, i.e. when liquid steel is solidified into a
continuous strand, with its break-through in the 1960s. Suddenly
it was possible to produce bigger volumes of steel – and with less
operations.
Oxygen converter steel-making and continuous casting,
have both strongly contributed to that half of the steel produced
in the world ever has been produced in the last few decades
(see diagram).
Now, it seems there is a 3rd revolution underway: the use
of oxyfuel combustion in reheat furnaces and annealing lines,
providing a highly cost-effective mean to drastically increase
production through-put, lowering fuel consumption and
addressing the increasingly important issue of environmental
concern by reducing CO2 and NOx.
Reheat and annealing furnaces
Reheat and annealing furnaces can typically be divided into two
groups: batch furnaces and continuous furnaces. The names and
designs of the furnace might differ but the main objective is to
bring cold or hot charged material up to a high and precise temperature, typically around 1200°C, for annealing of the material
or for the downstream processing. Continuous type furnaces are
common in large rolling mills and annealing lines, including, e.g.,
walking beam, pusher, rotary hearth, roller hearth and catenary
furnaces. The batch type furnace is frequently found at smaller
rolling and annealing operations and at forge shops. There are in
many cases a multiple of same type in a facility, including, e.g.,
soaking pit, box and car bottom furnaces.
Global steel production (in million metric tons)
1200
1000
800
600
400
200
0
1900
1910
1920
1930
1940
1950
1960
1970
1980
1990
2000
2002
2004
estimated
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Andreas Praller
Figure 1: Molded parts for auto interiors, handles of all types,
electronics housings or, as in this case, office chair parts are made
using gas injection molding (GIM) technology. Gases are injected
into the liquid plastic at high pressure and create parts with hollow
sections and excellent properties.
Industrial Gases Assist in Injection Molding
Nitrogen and Carbon Dioxide
Fill any Shape
Injection molds can be used to make any conceivable shape in plastic, from a toothbrush to
a thermos flask, from a glasses case to suitcase. Injection molding makes these products
less expensive since one mold can be used to make several million pieces. They must be as
like to one another as peas in a pod, and this can be quite a challenge, especially with more
complex molds. The parts of an office chair must fit together like a screw cap on a jar. The
solution to the problem is found in gases such as nitrogen and carbon dioxide, which are
injected into the mold with the plastic, ensuring that every last cavity in the mold is filled.
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Seite 15
Production shop
Cylinder bank
Single cylinder
Tank
Evaporator
Pressure
booster
Control
module
Injection molding
machine
Additional booster allows
higher pressure up to 500 bar
Membrane or PSA plant
Gaseous nitrogen
100 Nm3/h, 290 bar
Tank
DESY®
300/100
Evaporator
Figure 2: Nitrogen supply concepts for gas injection molding technology.
Conventional injection molding technology reaches its limits with
more complex die molds: Small recesses in the mold cannot be
filled reliably, which increases scrap and thus production costs.
This is where gases can help. They are injected into the molds at
high pressure and push the plastic up against the walls even into
the smallest recesses. The hollow created inside the plastic part
also saves on materials and makes the plastic part light and yet
stable. If necessary, after molding, the part can be cooled from
the inside out so that it cools faster, making for a speedier production process. And gases can do even more: As a foaming agent
they turn plastics into what are known as microcellular foams,
which have better mechanical properties than conventional
large-cell foams.
Gas Injection Molding (GIM)
In gas injection molding (Figure 1) nitrogen is used for the gas
because it is inert, i.e. it does not react chemically with plastics.
It is released from the component after hardening. Previously,
the main problem in GIM had been compressing the gaseous
nitrogen to high pressures cost effectively and with high purity.
This process requires a great deal of energy and high maintenance
on the compressors. What is more, the oil lubrication for the
compressors contaminates the nitrogen and lowers product quality
and process safety.
A convenient supply of high-pressure nitrogen thus considerably lowers costs in injection molding. One interesting alternative
to the conventional method of supplying nitrogen is offered by
the DESY® 300/100 high pressure system (Figures 2 and 3),
developed and patented by Linde. The liquid nitrogen is first
compressed to up to 300 bar. The nitrogen is then evaporated in
a high pressure evaporator. The main advantages of this system
are its very low energy consumption and an absolutely pure,
oil-free gas.
Unlike conventional cryopumps, this system automatically
adjusts the supply to the gas consumption – even with widely
fluctuating demand. For higher pressure requirements (over 300
bar) an additional booster, which requires very little energy, can
be used.
Logical Extension: Inner Cooling
Gas injection molding (GIM) with nitrogen can be supplemented
with inner cooling. This Linde-developed and patented technology offers additional benefits in the manufacture of cheaper,
lighter parts with greater dimensional accuracy. It can be used
for any product with a tube-shaped hollow, such as all types of
handles (Figure 4).
GIM inner cooling uses the high-pressure nitrogen that is
already present at the temperature of the surrounding environment. It moves in a controlled flow through the existing gas
channel, thus conducting heat away from the interior, resulting in
significantly faster cooling and shorter cycle times. The latter can
be demonstrably reduced by up to 30 percent, with only one to
three times higher nitrogen consumption. In addition, the inside
surface of the product is smoother and the dimensional stability
better than with conventional GIM products (Figure 6).
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Gaseous
nitrogen
100 Nm3/h
230 bar
Liquid
nitrogen
6 bar
DESY®
300/100
Evaporator
Optional:
Additional pressure
booster
Control module
Injection molding
machine(s)
Figure 3: DESY® 300/100, in combination with a high-pressure evaporator, is an advantageous
nitrogen supply system for gas injection molding.
Figure 4: When inner cooling used in addition to
GIM, even components with complex shapes can
be produced with high dimensional accuracy.
Expansion area
Core to be cooled
Capillary tube
Figure 5: Schematic drawing of the
spot cooling of a core.
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FI
TIR
FI
PIR
Cavity 1
PIR
Cavity 2
TIR
PIR
A
B
C
Air 6 bar
GIM control module
To convert:
Connect to injection
molding machine
FIR
N2 300 bar
Figure 6: Test setup for GIM with inner cooling.
When looking at inner cooling, one must compare the amount
of heat to be removed from the product interior with the amount
of heat dissipated through the mold. Although the thermal
capacity in the conventional GIM process is generally sufficient to
cool the product, demand for additional cooling is rising due to
increasing pressure on cycle times and thus productivity.
The new inner cooling process from Linde achieves higher
cooling performance through supplemental gas flow. After the
normal gas injection, the nitrogen feed to the main gas injector
is interrupted and the injector opened up to the surroundings. At
the same time, nitrogen is fed into a second gas injector at the
other end of the gas channel. The nitrogen flows through the
entire gas channel of the product and leaves it through the main
injector, which thus becomes the outlet. The nitrogen pressure
and flow rate must be precisely controlled for this technology to
work properly.
The cost of the extra nitrogen, additional equipment,
redesigning the mold and above all installing the second gas
injector is far outweighed in comparison to the production
savings. To use inner cooling on existing GIM injection molding
machines, a second gas injector must be placed on the side
opposite the original gas inlet. Whether additional equipment is
required depends on what variant of GIM is used and on the
component itself.
CO2 Cooling (Spot Cooling)
Carbon dioxide (CO2) cooling is suitable for any product whose
cooling and cycle times need to be reduced – while retaining the
same high quality. It is especially useful for improving the cooling
of a mold’s hot spots: very thin points, small cores or localized
material accumulations.
To ensure high quality and short cooling times, cooling
must be distributed evenly throughout the mold. Water cooling is
of limited usefulness if there is inadequate space for cooling
channel bores. Especially long, thin cores or other hard-to-reach
mold points can create practical problems in cooling.
CO2 cooling of such hot spots thus complements water
cooling at exactly those points on the mold where conventional
cooling cannot be used effectively.
Supported by many years’ experience with cooling technologies and in cooperation with ISK Iserlohner Kunststofftechnologie GmbH, Linde developed and refined a method of spotcooling standard steel. Liquid CO2 flows at high pressure (approx.
60 bar) through thin, flexible capillary tubes (outside diameter
1.6 mm or smaller) to the exact area to be cooled (Figure 5).
As the CO2 expands, it creates a mixture of gas and snow with a
temperature of approx. -79 °C and a high cooling capacity. In
doing so, the CO2 removes the heat from the steel and exits the
mold as a gas through the corresponding outlet channels.
This can reduce cooling and cycle times enormously (the
latter in some cases by 50 percent or more). The advantages of this
highly efficient cooling method, which include lower investment
costs and ease of installation, make spot cooling very attractive –
both for new injection molding dies and for upgrading existing
molds.
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Figure 7: Injection molding mould for a car head-
Figure 8: By cooling the middle die land with CO2, the cycle
light housing with spot cooling. The hardware
times in the production of the car headlight housing could be
required (solenoid valve block and capillary tubes)
significantly reduced.
can be seen on the left side of the mould.
A thermal analysis of the tool is conducted to determine
exactly where to place the capillary tubes. The CO2 is pulsed
using solenoid valves and a control unit. The hardware expense
is low.
Toolvac® technology is used to provide optimal CO2 cooling
of a larger area of the mold or even the entire mold. This is a
specialized cooling technology, which uses molds made of
porous steel and replaces water as a cooling agent with carbon
dioxide. The CO2 distributes itself evenly through the mold and
thus conducts the heat away better. Microporous steel can also
be used for ventilation – avoiding the so-called “diesel effect.”
Microcellular Foams
Microcellular foams have uniform cell structures with very small
bubbles (smaller than 100 mm) and significantly better mechanical properties than conventional foam. They are made using
carbon dioxide or nitrogen under up to 500 bar pressure as the
foaming agent. There are several processes for making microcellular foams, differing primarily in how the foaming agent is
metered, where it is fed in and how it is mixed into the polymer.
In general, the foaming agent can be injected in the extruder
and mixed in the screw (MuCell method) or injected after the
screw and mixed in a separate mixer (ErgoCell or Optifoam
method) (Figure 9).
The foamed parts have a porous core and a compact outer
skin (Figure 10). Their main advantage is that they are significantly lighter, require up to 30 percent less material, warp less
and have no sink marks. The lower viscosity of the mixture also
demands less clamping force of the injection molding machine.
The disadvantage is that the surfaces are not suitable for highgloss applications.
Microcellular foam is created when there is high nucleation
rate of the polymer cells, under the influence of an additional
nucleation agent, such as talc or glass fibers. The foaming agent
injected into the polymer melt dissolves at high temperature and
high pressure, forming a monophase solution with the melt, in
which a large number of small cells forms. When the foaming
agent begins to diffuse, all of the cells grow at the same time
and to the same size. When injected into the cavity, the pressure
drops abruptly, the foaming agent becomes highly saturated in
the polymer and the foaming process begins. The rate of pressure
drop must be very high since a slower drop in pressure results in
large bubbles.
Abstract
With the development of nitrogen and carbon dioxide technologies for injection molding applications, higher-quality products can be made at lower cost. The innovative DESY® high
pressure system optimizes the nitrogen gas injection molding
technology and can be combined with a newly developed inner
cooling method for better cooling of products with a tube-shaped
hollow. By contrast, carbon dioxide is used in the cooling of
especially problematic areas of a mold, whether in addition to
water cooling in the case of spot cooling or to cool larger areas
using Toolvac® cooling technology. Both gases can be used in the
production of microcellular foams with better material properties.
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Cooling
Heating
Screw
Granulate
Drive
Compact boundary layer
Closed-cell foam
Plastic granulate is fed into a cylinder, in which the screw rotates. The granulate is kneaded,
Figure 10: Cross section through the structure of
compacted and homogenized to make a formable plastic mass. When it exits the extruder,
a microcellular foam (source: Demag Ergotech).
the plastic is shaped by a die and cooled afterwards.
Advantages of gas injection
molding (GIM)
–– Higher product quality due to better
surfaces, no sink marks
–– less warp and greater dimensional
stability
–– Lower cycle times due to
faster cooling
–– Reduced mold clamping force on
the injection molding machine
Advantages of the DESY® 300/100:
–– Very low energy requirement due to
cost-effective liquid evaporation
–– Constant high quality of parts produced
with gas injection molding due to
absolutely pure, oil-free nitrogen
–– DESY® 300/100 delivers the exact
desired quantity of nitrogen, even
when demand fluctuates widely
–– Small dimensions
–– Low installation and operating costs
Diesel effect
Banked air that cannot escape from the
mold is heated by compression (due to the
high injection pressure of the plastic into
the mold cavity) so high that scorch marks
are caused on the molded part.
The Author
Andreas Praller
Andreas Praller studied mechanical engineering at the Technical University of
Munich. He has been working as a Project
Manager in development and application
technology at Linde Gas since 1992.
Advantages of GIM inner cooling:
–– Up to 30 percent shorter cycle times
–– Higher quality, especially lower
statistical deviations from dimensional
stability, weight and shape of the
product
–– Smoother product interior surfaces
–– Very affordable (low installation and
operating costs)
–– Easy to install
–– Components with more complex
shapes can be produced
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Norbert Pfeiffer
Forklifts with Fuel Cells
The Only Byproduct is Water Vapor
With crude oil in ever shorter supply, the development of alternatives is already well
underway: Five years after the first hydrogen filling station opened in Munich, hydrogen
can now be obtained in several German cities. This eco-friendly alternative to gasoline
and diesel fuel is also becoming increasingly important for the logistics industry: Linde
subsidiary STILL GmbH recently introduced its first hydrogen-powered fuel cell forklift,
which is based completely on a production unit and is being used in current operations.
What was seen as a dream just a few years ago is now actually
taking shape. Hydrogen-powered vehicles are about to take their
place in the world of transport and logistics. There are many
indications that hydrogen vehicles will be part of everyday road
traffic in the not-too-distant future: The most recent price increases
are an omen that our fossil fuel supplies will be exhausted within
a few decades. Pressure to reduce greenhouse gas emissions is
also growing. As a result of this situation, efforts are underway
to accelerate the development of environmentally friendly alternatives.
For many years, STILL GmbH has been actively committed to
environmental protection at all of its locations. The Senate of
the City of Hamburg recently awarded the company a certificate
for its active participation in the city’s Environmental Partnership.
While previous efforts in the name of careful handling of resources
and eliminating harmful emissions were primarily associated
with technical and organizational processes, today at STILL the
focus is also increasingly on the products themselves. The company
has been working with various partners since 1999 to develop
drive and energy supply concepts that are superior to today’s
battery powered electric vehicles, which themselves are already
at a high level of development. The result is a forklift with a fuel
cell system, which has been in use at the Munich Airport since
July 2004 as part of a project of the Munich Airport Cooperative,
ARGEMUC. It is the culmination of the second phase of a multiyear project to study hydrogen (H2) infrastructures and the
practical operation of different classes of vehicles, such as buses
and passenger cars.
The aim of Phase 2 of the airport project is to protect against
the technical and economic risks of this revolutionary technology,
which is viewed throughout the world as having a high potential
for implementation. Linde Gas signed on as responsible for the
conception and design of the H2 components. PROTON MOTOR
GmbH took on the development and manufacture of the fuel cells
and the hybrid concept (the use of an intermediate accumulator,
see below). STILL provided a Series 60 forklift with a lifting capacity
of 3 t, which is similar to a production model, but adapted to the
new system at the essential mechanical and electrical interfaces.
Today’s traction batteries in the forklift
The minimum requirements for a fuel cell forklift were based on
the characteristics of a forklift with a lead-acid based traction
battery as used today (Figure 1). As the central element, with
approximately 1.6 t dead weight, this battery takes up a volume
of approximately 1 m3 and has an energy charge of 600 Ah with
a voltage of 80 V. Without deep discharge, the usable energy
content is approximately 40 kWh. In normal use, this is sufficient
for an operating period of eight hours or one working shift.
Multi-shift use requires a change of batteries and a changing/
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STILL R60
A = 790 mm
B = 1035 mm
Proportion of battery to vehicle volume
(Chassis) 35 - 45%
Weight (t)
1.6 - 2.0
2.0 - 2.5k
2.5l - 3.5
4.0 - 5.0
Battery
3PzS420
4PzS480
5PzS600
6PzS720
C (mm)
580
722
865
1013
Figure 1: Dimensions of various types of forklift batteries.
recharging station. With optimal maintenance, operators report,
these batteries can last for 800 to 1500 load cycles. Depending
on the technology, recharging can be expected to take from five
to twelve hours, although quick-charge technology can also
enable shorter charging periods. Moreover, additional recharges
during the week can considerably extend the usage times and
make battery changes unnecessary. Under these conditions it
can be possible to postpone a complete recharge until low-use
times such as over the weekend, depending on capacities, which
generally only the larger users have.
Advantages of a fuel cell
–– Filling instead of charging
–– No changing batteries
–– No or short interruption of use
–– Multi-shift operation without problem
–– Higher power and energy density
–– All environmental and energy policy reasons
–– No pollutant emission (CO2)
–– Limits for further optimization of conventional
battery technologies are achieved
–– Longer useful life aimed for
Requirements for fuel cell forklifts
The advantages of fuel cell operation are obvious: Instead of
charging a battery or using an extra battery, a three-minute
fill-up is all that is required. What is more, the tank can be refilled
from any fill level.
The partners selected a pragmatic approach for the fuel
cell forklift: The battery should be replaced with a completely
equivalent system. This meant that the same energy should be
available in the same space and that all system components
were to be housed in this space as well. This approach made it
possible to use a production unit, which was the main difference
between this and all previous attempts to use fuel cells in
forklifts. It meant that the forklift should have no limitations as to
load capacity, range or driving and lifting dynamics. Thus, there
had to be an effective usable energy of about 40 kWh on the
clamps – with identical performance data. This, in turn, made it
necessary to provide for brake energy accumulation to extend
the range and unlimited acceleration and lifting dynamics.
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Gas tank
(350 bar; 2 kg H2)
Intermediate accumulator
(54 F, 72V-112V)
Weight
Cooler
Compressor
Fuel cells (3 x 6kW)
Figure 2: Installation conditions for a fuel cell system
The H2 fuel cell system
Based on these requirements, a system was conceived with
hydrogen as the energy carrier. All system components are
housed in one massive steel box. There are six essential parts
(Figure 2):
1. Hydrogen accumulator
The required energy is stored in the form of 2 kg gaseous hydrogen.
Two tanks, each with a volume of 39 l, based on a bandaged
aluminum core, are used, for which type approval and various
tests are available. This solution is more cost-efficient than an
accumulator for liquid hydrogen or a metal hydride accumulator.
A 350 bar system is the current state of the art and tanks with
up to 700 bar are in development. Electromagnetic valves are
integrated in the tanks.
2. Fuel cell modules
The hydrogen is converted in PEM (proton exchange membrane)
modules. There are three modules with 6 kW continuous output.
The voltage level is an idle voltage of 110 V, which corresponds
to the upper limit of the lead battery.
3. Compressor
Oxygen from the surrounding air is needed to react with the
hydrogen. The electrically driven, speed-controlled air compressor
provides up to 100 m3 air per hour depending on requirements.
One noteworthy element is the low-pressure technology used by
PROTON MOTOR, with an operating pressure below 0.1 bar, which
helps minimize compressor demand and noise.
4. Cooler
The efficiency of the conversion into electrical energy is approximately 60 percent. It is thus significantly better than a modern
combustion engine, with a maximum of 40 percent, however
considerable heat must still be conducted away. Since a
maximum of 80 °C can be allowed inside the modules due to the
operating method, a correspondingly large cooler is required.
5. Intermediate accumulator
The electrical intermediate accumulator is based on dual-layer
capacitors (Ultra Caps). The braking energy is absorbed by 48
sequenced capacitors with 2,700 F each, which balance out the
load peaks as well.
6. Weight
Looking at the required load capacity, the missing weight of the
lead battery is compensated for with additional weights of about
1.2 t. Although a ton of steel is certainly cheaper than a ton of
lead battery, it does not make for a satisfactory solution for a
series production forklift. Alternatively, the counterweight could
be dimensioned differently in future forklifts.
System function
The functional relationships are shown in Figure 3: Within the air
section, filtered ambient air is sucked in and supplied as needed.
The compression occurs here only at low pressures in a range of
no more than 0.1 bar overpressure. The compressor essentially
determines the dynamic behavior of the cell.
After the reaction in the fuel cell modules, the exhaust air is
heated to about 70 °C and loaded with water vapor. In normal
operation, there is about 1.8 L of water in the form of vapor to
deal with as the “exhaust”. This is considerably less vapor than is
produced by a combustion engine and brings with it absolutely
no harmful substances. The vapor is carried off by a special
exhaust pipe.
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Forklift control
System controller
N2
Nitrogen tank
200 bar
H2
Hydrogen tank
Ambient air
350 bar
0.2 kg/h
Air: 60-100 m3/h
Catalytic
converter
Reducing
regulator
Reducing
regulator
Air filter
DC
DC
Reducing
regulator
20 bar
0.3 bar
Compressor
Environment
Fuel
cells
Ultra
Caps
Forklift drives
Air: 60-100 m3/h
0.x bar
24 V Battery
H2O: 1.8 l/h
Environment
H2O 8 l/min
ca. 70°C
Water pump
Cooler
Cool air: 800-2500 m3/h
Figure 3: Function of the hydrogen fuel cell system
The other ingredient in the reaction, hydrogen, travels from the
parallel tanks to the modules via a two-stage pressure reduction.
There is then a constant working pressure on the hydrogen side
of the fuel cell. It is necessary to rinse out the hydrogen side
regularly. To ensure a safe hydrogen reaction, this is diverted
through a catalytic afterburner, where there is a defined oxidation
of the hydrogen. With the present state of technology, about
3 percent of the hydrogen goes unused through the modules.
The third medium is nitrogen. This serves as a safety element, which permits safe indoor use. Each time the system is
switched off, a short automatic rinsing process is started, which
removes the remaining hydrogen from the modules. Without this
rinsing process, a residual amount of hydrogen would remain in
the fuel cells when they were switched off. This would then react
with the available oxygen to form water and cause a pressure
differential of up to 1 bar between the hydrogen side and the air
side, which would cause a mechanical load on the membrane
and shorten the life of the system. With the goal of reaching up
to 20,000 operating hours, using nitrogen means taking the safer
but also the more expensive road. It is also the right road for forklift operation for safety reasons, since it is designed to be used
and stored in a normal building environment and not one that is
specially designed.
The cells are cooled by circulating deionized water. This
medium has a few advantages: For one there are no electrical
cross-flows in the cells, because the individual cell plates are
not designed to be insulated from the coolant; for another the
pressure drop in the modules is lower than with a frost proof
water-glycol mixture. Thus an electric water pump with lower
power can be used. The heat is carried away via a stainless steel
cooler with an integrated ventilator, controlled as needed. This
circuit is designed for an average loss performance of about 13 kW.
The electrical output is comparable to that of a lead battery:
A plug connector with two terminals with 80 V at the measurement power of 18 kW and a peak power of 38 kW. Depending on
the system load or the feedback, the voltage is within a range of
between 72 and 110 V. Additional voltages (24 V or 12 V) are
generated by DC/DC converters. In addition to the vehicle control
there is a separate control for the complete fuel cell system.
Logistics requirements
Highly dynamic logistics processes place special requirements on
the system characteristics and the system behavior of the forklift’s fuel cells. Forklifts must be able to react to jumps in load,
which can stress the electrical and electronic modules and parts.
A simulation model provided efficient support in the design and
in knowledge building about the interrelationships (Figure 3). In
particular, connecting the capacitors (Ultra Caps) with the slow
fuel cell modules requires a detailed knowledge of the power
profiles of the electric drives in the forklift in order to be able to
access increased power for load peaks with little or no delay.
In addition to the behavior of the fuel cell, the energy consumption
plays an important role. Models and working cycles help to figure
this out. Because the fuel cell system has a higher voltage than
the electric battery drive, the losses are somewhat less. A few
special load cases, such as driving up a long ramp, require special
control interventions.
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Latin America 2.2%
Other 3.6%
Electric forklifts 18.7%
North America 24.9%
Warehouse trucks 40.2%
Asia 25.4%
Europe 43.8%
Combustion engine forklifts 41.1%
Figure 4: Global industrial truck market by region 2003 –
Figure 5: Global industrial truck market by type of unit 2003 –
Sales (100% = 590,058 pc.)
Sales (100% = 590,058 pc.)
Source: DHB Tab. 1.3.
Source: DHB Tab. 1.3.
Hydrogen filling stations
ARGEMUC
The hydrogen forklift in action
California is the pioneer: By 2010, says
Governor Arnold Schwarzenegger, a network
of hydrogen filling stations will cover the
state. Already today more than half of the 24
hydrogen filling stations in the United States
are found here. In Europe, it is Germany that
is the pioneer state as far as hydrogen filling
stations. 13 of Europe’s 22 hydrogen filling
stations – out of 74 worldwide – are located in
major German cities. And number 14 followed
in Berlin in November 2004: The district of
Spandau now boasts the first public filling
station to sell the ecologically friendly fuel
alongside gasoline and diesel – here too
with Linde hydrogen technology.
ARGEMUC is the cooperative of the eleven
partner companies participating in Munich
Airport Hydrogen Project. The aim of this project is to demonstrate the complete hydrogen chain from generation to use and to
show the reliability of today’s hydrogen technologies. The vehicle fleet realized thus far
includes passenger and commercial vehicles.
The Linde Group is represented both in the
hydrogen generation (steam reformer) and in
the hydrogen use (fuel cell driven forklifts).
Since mid-2004, the forklift truck has been
gradually introduced into routine operation
at Cargogate Flughafen München GmbH at
Munich airport. Cargogate’s drivers quickly
became familiar with the forklift in a halfday training session and can attest to its
good handling and excellent performance.
Initial consumption measurements indicate
that the average operating time of eight
hours per tank filling will probably be
exceeded. In order to gain a broad basis of
experience and to further optimize the unit,
a trial operation of one year is planned.
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Figure 6: The large lever creates a pressure-sealed, non-positive
Figure 7: View of the hydrogen fuel cell system of the STILL forklift.
lock between the tank connector and the H2 tank line.
The safety of hydrogen systems
Safety takes high priority in H2 systems. In order to achieve the
goal of unlimited indoor use of H2 forklifts, there were some
safety hurdles to be overcome. Commitments were made and
precautions taken in close coordination with TÜV Süddeutschland, defining three areas:
1. The highest safety standards are met for hydrogen supply.
For example, all components used at critical points have
either type approval or individual acceptance. Safety elements
require special certification. The functions are made redundant
or sometimes double redundant.
2. The fuel cell modules are located in an area with a defined and
monitored airflow provided by an explosion-proof fan. Sensors
monitor the occurrence of leaks. In case of malfunction, catalytic converters are in place to oxidize any hydrogen that
escapes. Other elements, such as the cooling circuit and the
electrical connections, are located in a cross-ventilated area.
A failure mode and effect analysis (FMEA) as well as a risk
analysis could also require a CE conformity declaration even
for the prototype.
3. The connectors for the tank line have an internal code for
the 350 bar level (Figure 6). The large lever brings about a
pressure-sealed, non-positive locking of the tank line with
the tank connector.
Prerequisites for economical use
It is clear from the global market figures for industrial trucks that
the volume of the forklift industry will not be sufficient to use
fuel cell technology economically in the short term (Figures 4
and 5). Support from the automotive sector is needed with
regard to the actual fuel cells (stacks), as these are the most
cost-intensive element of the system. This is purely an issue
of production volume, since the function and operation are
different. The forklift as a working machine has even higher
demands placed on it than the automobile. The commercial
vehicle sector on the other hand is more similar to the forklift
and can help reach the required quantities with regard to
components such as the H2 supply and the cooling concept.
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Outlook
From concept to the use of the forklift at Munich Airport, there
were many obstacles to be cleared out of the way. The efforts
have paid off, however. The next project will possibly be in
Hamburg, since that city wants to take a leading role in the area
of H2 use in Germany and in Europe. But also in the Hoechst
Industrial Park, in Berlin, North Rhine Westphalia and in the
United States there are good opportunities for Linde both as a
provider and a user of industrial trucks to take on a world-leading
role. There, as in Munich, they will still be pilot projects, however
they will prepare the way for a broad application for hydrogen
and fuel cell technology. Over the long term, as other experts
also confirm, hydrogen technology will be the key component for
an efficient and sustainable energy industry. Although, despite
recent progress, there is still a long road to travel before the
mass production of fuel cell forklifts. Linde will continue to be
involved with this technology. Finally, there are a number of
good arguments for the use of fuel cells. And experience for a
subsequent series production solution can only be gained
through practical use.
The Author
Abstract
The Linde subsidiary STILL GmbH has developed the first forklift
with hydrogen fuel cell technology, which is similar to a series
production unit and is used in current operations. The fuel cell is
housed in the battery shaft of the production unit. Only the
mechanical and electrical interfaces have been adapted. It has a
higher power and energy density and a longer service life, while
at the same time reducing the pollutant output to zero. Unlike
battery-operated forklifts, it is not necessary to recharge or to
change the battery. The hydrogen driven forklift has been in use
at Munich Airport since July 2004.
Literature
Leifert, T.: Brennstoffzellen im Gabelstapler
TÜ Vol. 44 (2003) No. 4
Norbert Pfeiffer
Norbert Pfeiffer, Director Product and Business Strategy for the
Executive Board at Linde Material Handling since July 2004, has
vast experience in all of the business segments of Linde AG. After
completing his apprenticeship in business administration in the
Refrigeration Division in Wiesbaden from 1959 to 1961, he
studied on a scholarship of the Dr.-Friedrich-Linde Foundation
Industrial Engineering and Management at TH/TU Darmstadt
until 1970 where he graduated with an engineering and commercial degree. From 1970 until 1980 he held a number of
cross-functional positions within the Linde family of companies
each with increasing levels of responsibility. After a period as
head of manufacturing technology at Linde’s Corporate Center in
Wiesbaden and Manager of Manufacturing and Materials at the
Baker Material Handling division in Cleveland, Ohio, he became
in 1987 Technical Managing Director of Wagner Fördertechnik
(today STILL-Wagner), and in 1991 also of Indumat both in Reutlingen. In 1994 he assumed the position of Technical Managing
Director and Member of the Board of STILL GmbH in Hamburg.
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Japan’s first filling station for liquid hydrogen is open
for business in Tokyo since 2003 – with innovative storage
and filling systems from Linde.
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Dr. Hans-Jürgen Maaß and Dr. Karin Bronnenmeier
New Trends in Pharmaceutical Industry
Future Market: Biotechnology
In search of new drugs the pharmaceutical industry today is profiting greatly from the
dynamic growth in knowledge of genetics and cell biology. Innovative drugs are produced
for example by genetically modified cells and permit completely new therapeutic
approaches. Culture of such cells and recovery of their products on an industrial scale place
complex demands on the conception of biotechnological plants.
Biotechnology belongs to those future technologies, which
owing to the potential for innovation and the bright prospects of
the market will leave their imprint on the technological face of
the world in coming decades. In pharmaceutics, biotechnology
is presently bringing about a qualitative change: Innovative
drugs, which are produced by means of genetically modified cell
systems, permit new therapeutic concepts. In the future, it is
hoped, drugs will act specifically on for example cancer cells
and therefore will have fewer side effects on healthy tissue than
chemotherapy, radiation or surgical removal of tumors.
Dynamic Development
The therapeutic strategies and, starting from there, the development of drugs with specific action on cancer cells, was only possible as a result of great innovative activity in associated fields of
knowledge.
The following examples may be mentioned here:
–– Molecular cell biology and genomics, which elucidated the
mechanisms regulating growth and reproduction of living
cells, as well as basic medical research resulting in precise
descriptions of the body’s immune system and of tumorigenesis;
–– Nanotechnology for the visualization of structures and
mechanisms in living cells on a molecular or macromolecular
level;
–– Gene technology, which by means of recombination is able to
modify genes and insert new genes into cells thus permitting
tailor-made development of drug substances in line with
therapeutic strategies;
–– New production methods, which make it possible to produce
these novel drug substances on an industrial scale.
The causes and clinical pictures of carcinogenic diseases are
complex and can mostly be attributed to changes in the genome
of individual cells. A completely new scientific discipline,
pharmacogenomics, has developed for the identification of the
mechanisms of drug action, the early detection of disease and
the proper selection and dosage of drugs. Based on the analysis
of the genetic material, the DNA, of for example human blood
or skin cells, pharmacogenomics identifies the genetic factors
associated with disease and characterizes the interactions of
drugs and the complete set of genetic factors, the genome. It
thus provides the basis for individualized medicine, which allows
a specific diagnosis to be followed by a individually tailored
therapy. Pharmacogenomics has developed into one of the
most dynamically growing fields of the pharmaceutical industry
and, along with improved drug substances, will support their
development and therapeutic success.
Biotechnology – Challenge for the Plant Designer
The path of a drug from discovery of a substance to its regulatory
approval, production and delivery to pharmacies or physicians
is difficult and costly (Figure 1). The resulting challenge and
prospective tasks faced by a plant designer in pharmaceutical
biotechnology can only be described provided that the dynamic
change in therapy-oriented trends in product development is
tracked and the strategic environment of the pharmaceutical
industry is assessed.
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Figure 1: Path of a drug from discovery to delivery to pharmacies.
Source: Bayer AG, modified
Research 2-10 years
Discovery
Laboratory and animal tests
Preclinical development
20-80 healthy volunteers
Determination of safety and dosage
Clinical Phase I
(first use in humans)
100-300 patients
Test for efficacy and side effects
Clinical Phase II
1,000-5,000 patients
Confirmation of efficacy/tolerability,
side effects in long-term use
Clinical Phase III (broad clinical use)
With material from the final process,
proof of principle
Review
FDA, EMEA or national authorities
Approval
Follow-up testing
after launch
Phase IV (post-marketing)
Pharmaceutical companies
Design phases
Construction phase
Qualification, startup, validation
Authority permits
Credit granting
Plant designer
Design
Construction
Qualification, startup
0
2
4
6
8
10 12 14 16 Years
Table 1: Biotech ”blockbusters” with sales of more than a billion US dollars.
Product
API**
*Procrit
EPO
*Epogen
EPO
Intron-A
Interferon
Remicade
MAK
Enbrel
MAK
*Epogin/Neo Recormon
EPO
*Aranesp
EPO
Rituxan
MAK
Neulasta
G-CSF
Neupogen
G-CSF
Avonex
Interferon
Humulin
Insulin
Humolag
Insulin
** Total EPO sales: 9.5 billion US dollars
Source of data: Ernst & Young Report 2004
** API, Active pharmaceutical ingredient
Company
Sales 2003 (billion US$)
Johnson & Johnson from Amgen
Amgen
Schering-Plough from Biogen Idec
Johnson & Johnson from Centocor
Amgen and Wyeth from Immunex
Roche and Chugai Pharmaceuticals from Genetics Institute
Amgen
Biogen Idec
Amgen
Amgen
Biogen Idec
Eli Lilly from Genentech
Eli Lilly
4.0
2.4
1.9
1.7
1.6
1.6
1.5
1.5
1.3
1.3
1.2
1.1
1.0
29
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Biotech Products Revolutionize Pharmaceutics
Figure 2: Generation of genetically modified cell systems by the technique of recombination,
described by the example of a bacterial system.
Source: Brochure Science Live, BMBF, modified
1. Donor cell: human cell
2. Host cell: Bacterium
Plasmid (DNA):
Additional genetic information
Genome (DNA):
Genetic information
Genome (DNA):
Basic genetic information
Isolation of genetic information:
1.1 Genomic DNA from human cell
2.1 Plasmid DNA from bacterial cell
Generation of fragments:
1.2 Isolation of DNA fragment (gene) with information
for the product, e.g., the insulin protein
2.2 Opening plasmid DNA
Cloning of fragments:
3.1 Inserting DNA fragment in plasmid DNA.
Result: a recombined plasmid
3.2 Transferring plasmid in host cell (bacterium)
Genetically modified bacterium, which
can be cultured and thereby produces
the product, e.g. insulin
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For these reasons, the following will be analyzed:
A the status and trend of product development by genetic
engineering,
B the exceptional entrepreneurial challenges of biotechnology
to the decision-making processes of the pharmaceutical
industry, and
C the positioning of Linde pharmaceutical plant design and
construction in this environment.
A. Trends in Product Development by
Genetic Engineering
The greatest change in the pharmaceutical industry has been
the switch from chemically synthesized to biotechnologically
produced drug substances in the last five to ten years. Currently,
erythropoietin (EPO)* is the first biotech product to capture
the top position as the best-selling pharmaceutical product in the
world (Table 1).
Characteristic milestones in the use of genetically modified
cell systems* for the production of active pharmaceutical
ingredients (APIs)* were:
“Imitation“ of human biosynthesis of insulin in systems with
genetically modified cells. Via the technique of genetic recombination, the DNA fragment, which in human cells contains the
production code for insulin, was inserted in bacteria (Figure 2).
“Modification” of the DNA of the human insulin gene and
thereby modifying the molecular structure of the insulin protein
with the objective of altering the profile of action in the patient’s
body by producing especially fast-acting or especially longacting
insulins. Thus, more closely adapted therapies for the individual
patient are possible, and the insulin level can be kept uniformly
high, which among other things results in greater wellbeing of
the patient (cf. “Linde Technology“ 1/2004).
Use of mammalian cells, normally CHO cells*, as host cells for
human DNA fragments. Because of the closer “similarity” of CHO
cells to human cells, the range of possibilities for the development
of new medicinal drugs and/or mechanisms of action was
increased. At the same time, the technological difficulties of
maintaining the conditions for life and growth of these highly
sensitive cell systems increased. An example of this product
category is EPO.
Development of monoclonal antibodies (MABs)*. The
qualitative step of gene technology from DNA-based imitation
of human substances to initiation mechanisms in the immune
system was taken with MABs.
MABs are the basic elements for a high-tech scientific
answer with adequate active principles to, among other things,
the extremely complex disease-related defects in the genome of
man. Antibodies have “search systems” of their own for foreign
substances in the body – including those on the surface of cancer
cells – and act via activation of the immune system. Today genetic
methods allow MABs to be altered or specifically constructed in
such a way that they can also recognize endogenous substances
in the body. These properties have made MABs the great bearers
of hope in the fight against cancer. An example of this product
category is Avastin®, which was recently approved for the
treatment of colon cancer. In 1984 César Milstein, Georges J. F.
Köhler and Niels K. Jerne received the Nobel Prize in Medicine
for development of the method for production of MABs.
A special group of biotech products consists of herbal substances.
Because of the limited natural resources of rare or slow-growing
plants these substances are nowadays produced biotechnologically as well. For this purpose, the corresponding plant cell is isolated and propagated in bioreactors under suitable culture conditions. The slow growth of plant cells places great demands on the
sterile processing technology of the production facility. Plant cells
are used for example for making special products for the chemotherapeutic treatment of tumors. Figure 3 shows the original
plant and the molecular structure for one such product having
more than a billion Euro in annual sales.
Linde-KCA-Dresden is at present working for a large US
company on the cultivation of plant cells on a production scale.
* Glossary, see pages 36 and 37
O
O
O
NH
Me
Me
O
Ph
Me
OH
H
O OAc
OH
O
Figure 3: Antitumor agent Taxol® Original plant and molecular structure.
By courtesy of Dr. Dietrich Ober, Institute for Pharmaceutical Biology, Braunschweig Technical University
OH
Me
O
31
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The Market for Products made by Genetic Engineering
Beginning with insulin in the year 1986, over 100 products have
now been granted marketing authorization in Germany (Figure 4).
Among new drug substance approvals, biotech products have
now overtaken chemistry production and are increasingly
entering the ranks of top pharmaceutical products.
However, the number of drugs under development (Figure 5)
or the number of persons employed in research-oriented biotechnology centers, so-called clusters (Figure 6) is a better indication – in terms of future potential – of the international distribution of roles. The predominance of the USA and the secondary
standing of Germany in product development is evident: If one
considers - with regard to market capitalization – the first thirty
companies that have specialized exclusively in biotechnology,
there is only one non-Anglo-American company, Serono (Switzerland), among them. There are no German companies at all at the
top. Thus, German companies have not only fallen behind with
respect to market position but they have also failed to recognize
the necessity of specialization, which would require a split-up
of “mixed” pharmaceutical companies into separate corporate
entities focused on biotechnology and chemistry. This assessment is supported by the fact that not a single German company
is found among the ten largest worldwide pharmaceutical groups.
As to important biotech products such as MABs, US and
UK companies predominate, in terms of both market share and
technology. In Europe, projects based on monoclonal antibodies
are primarily fed by US know-how (i.e., licenses) or are direct
investments of US companies. Blockbuster biotech products
are also an indication of the dominance of the USA: Of the 13
best-selling products, only one product is originally based on a
German patent (Table 1).
The observation of trends in biotechnology enables the plant
designer in the pharmaceutical industry at an early stage
–– to identify and work on innovative projects and technologies
with future potential, thus achieving a leadership position
in this field of engineering, with respect to market share and
references;
–– to adapt its personnel profile, personnel training, design
algorithms and design tools to market conditions;
–– to focus its acquisition activities on companies with high
development and market potential.
B. Strategic Environment of the
Pharmaceutical Industry
Entrepreneurial decisions have become increasingly difficult for
pharmaceutical companies active in biotechnology in recent
years. On the one hand, the dimension of decision-making relates
to the success of the company in its core: The costs of product
development up to start of production are exceptionally high and
in some cases amount to more than a billion Euro. Thus, only
a few products can be developed all the way to approval and
registration. However, they may then have the prospect of sales
volumes of more than a billion Euro per year.
On the other hand, the fundamentals for decision-making
are often hard to assess, since decisions to prepare for production
must be taken exceptionally early because of the “time to
market” situation and the long product development time
(Figure 1). Making this more difficult is the fact that at this point
in time no reliable data exist as to costs and time schedule of
the development phase and as to the prospects of efficacy and
regulatory approval of the product. In addition, the competitive
situation with respect to products of competing companies with
either identical mechanism of action or competing mechanism
but possibly better therapeutic results is not clearly known.
Uncertainty also often prevails concerning the availability or the
status and quality of licenses – in the end, European and German
pharmaceutical companies are largely dependent upon knowhow from the USA, due to the latter's head start in the field of
genetically modified production systems.
As a result, a small number of risky product developments
determine the success or failure of even large companies. In
view of the dynamic environment of biotechnology described
above and the possible consequences of company decisions, the
extremely sensitive reactions of the stock exchange to positive
or negative evaluations of biotech products may be better
understood.
C. Strategies for Plant Design
and Construction
For a plant designer, who is only brought in to the picture at
the end of the long and hard-to-predict chain of decisions, there
is a high risk in the evaluation of the likelihood of success of
projects as well as in the development of its own planning
strategy for biotechnological plants. This risk can only be dealt
with by accurate knowledge and correct assessment of the
interrelationships and influences involved. This includes
consideration of the distinctive features of biotech plant design:
Development and design in parallel: Because of the innovative
character of the products being developed and the “time to
market” pressure, process and product development proceed in
parallel with design. The classic model of plant design and construction with established and proven processes as a prerequisite
for the start of basic engineering is thus invalid per principle.
With regard to biotech know-how transfer from the licensor to
the plant designer during concept and basic engineering, this
approach requires close collaboration – usually at the customer’s
site – among licensor, ultimate plant operators, customer’s
engineering specialists and plant designer. The smooth transfer
of know-how into the project during ongoing design and the
compliance with the project objectives are thus ensured.
Customized solutions: Each project is unique, frequently with
new technologies and unit operations for which only limited
process information is available. Therefore new solutions have
to be worked out during the design phase.
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Figure 4: Biotech products on the market (Germany).
Source of data: Verband forschender Arzneimittelhersteller e.V.
Insulin
110
109
100
90
80
68
70
60
48
50
40
32
30
23
20
10
1
0
1986
7
1988
11
1990
16
1992
1994
1996
1998
2000
2002
2004
Figure 5: Biotech products under development: Comparison of the product pipeline of companies listed on the stock exchange in Europe and the USA.
Country
Phase I
UK
37
Switzerland
8
France
12
Denmark
7
Sweden
7
Ireland
2
Germany
3
Norway
2
Finland
1
The Netherlands
1
Belgium
0
Total
80
Clinical test
Phase II
46
14
8
7
8
2
2
2
1
1
1
92
Total
Phase III
27
20
1
4
1
5
2
3
1
0
0
64
110
42
21
18
16
9
7
7
3
2
1
236
Figure 6: Selected biotech clusters: Persons employed in biotechnology.
Europe – 94 companies listed on the stock exchange
In 2003 Europe’s “Top Biotechs” had a total of 236 products
in clinical development.
Source of data: Ernst & Young Report 2004
USA – 314 Biotech companies listed on the stock exchange
In 2000 the “Top 100” biotech companies had a total of 574 products
in clinical development.
Source of data: EuropaBio, The European Association of Bioindustries
Source: BCG Study 2001, modified
Size of companies (number of employees)
140
Bay Area, USA
120
100
Boston, USA
80
60
Cambridge, UK
40
Rhineland, D
20
Rhine-Neckar, D
Munich, D
0
0
50
approx. each 1,000 jobs in the region
100
approx. 6,000 jobs in the region
150
200
approx. each 20,000 jobs in the region
250
Number of companies
33
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Front-End Engineering
For these reasons, the plant designer is being brought into the
project by the customer earlier and earlier and now collaborates
already in the preparation of investment decisions (feasibility
phase). There, questions of process risk, scale-up, cost estimates
and time schedules up to start of production come to the fore.
The plant designer’s experience is also being used more and
more frequently to assess biotech investment projects or to
evaluate and compare locations on an international level. Last
but not least, the customer often wants strategic support in
project management.
Linde-KCA-Dresden has summarized this task profile under
the term “front-end engineering”. Today front–end engineering
is an important and successful marketing and sales tool for
an early entry into customers’ projects. Linde-KCA-Dresden now
generates most of its pharmaceutical projects in this way
(cf. “Linde-Technology“ 1/2004) and is the market leader in this
field. A prerequisite for this success has been the continuing
analysis of trends in the pharmaceutical industry. Front-end
engineering is made possible by expanded competencies of the
individual employees as compared to those required within
a standard split of work approach and by a personnel structure
that covers the value chain from feasibility study to startup.
Qualification
Additionally and carried out in parallel to other disciplines, a
step for quality assurance of the finished pharmaceuticals is integrated into the design and execution phases of biopharmaceutical
projects. Quality assurance is carried out according to strict
international rules and is a requirement for the approval and
registration of drugs. Quality assurance includes definite rules
for design and testing of plants as well as, in particular, the
documentation of work steps. Very high demands are also placed
at the IT level, in order to ensure complete traceability of all raw
material, intermediate product and finished product batches
for a ten-year period of record-keeping. Thus, the automation,
control and information systems of biotechnological plants have
higher requirement levels and a larger scope than large industrial
plants.
The overall task is summarized under the term “qualification”
and is an inherent component of plant design. Thus the protection
of human health is given the highest priority.
Linde in Biotechnological Plant Design
and Construction
Linde-KCA-Dresden has been technologically associated with the
development of biotechnology from the early stage products
such as insulin through the fractionation of blood plasma all the
way to demanding projects with genetically modified systems
with bacteria, yeasts and animal cells (Table 2 and Figure 7).
Linde-KCA-Dresden today is one of Europe’s market leaders and
holds a top position with respect to services, orders, references
and personnel profile. Thus, Linde is main contractor for one of
the largest and technologically most advanced European projects
for monoclonal antibodies and hence is active at the very forefront
of biotechnological development, design, and production of
drugs for the fight against cancer.
A great market potential can be predicted for pharmaceutical
biotechnology. The reasons for this are multiple: Since the midnineties, the values of investment in biotech plants have risen
from 10 to 20 million Euro, predominantly for pilot plants and
small scale production plants, to about 300 million Euro for large
scale production plants today. Along with this, there are a large
number of biotech products in the pipeline of pharmaceutical
companies and the areas of application are expanding beyond
pharmaceuticals up to food. In addition, the market conditions
for plant design with respect to split of work have improved. This
results from deeper knowledge of the special requisites and
basic conditions governing pharmaceutics, on the part of both
investor and plant designer. Additionally, the trend in plant design
goes to an extension of the value chain along with increasing
project size, broader scope of work and constantly increasing
and changing technological requirements (Table 2).
Based on the experience and references that Linde-KCADresden has in this area, there are good prospects for technical
and commercial success in a highly innovative field of work
with a lot of reputation to gain. This is clearly underscored by the
following assessment of the market situation, coming from
capital market circles:
“A large number of additional monoclonal antibodies, which
bind to a great variety of cancer cell-specific surface molecules,
are now found in the pipeline. The increasing importance of
humanized monoclonal antibodies in cancer therapy faces
production with new challenges. In contrast to small molecules,
which can be produced relatively easily in large quantities by
established speciality chemistry companies, the production of
antibodies has substantially higher requirements and is definitely
more capital-intensive. Here we expect a new industry of
specialized contract-manufacturers to develop.” (GoingPublic
Magazin “Biotechnology 2004“)
Abstract
The biotechnological production of novel drug substances, for
instance for anti-cancer treatment, places special demands on
plant design and construction: In a period of dynamic developments
in biotechnology, trends must be recognized in timely fashion
and answered with flexible structures for design and execution.
Due to the implementation of front-end engineering, Linde-KCADresden is a market leader in biotechnological plant design and
construction and is well positioned to master the challenges of
the future market of biotechnology.
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Figure 7: Biotechnological plant for the production of EPO.
Table 2: Linde biotechnology projects.
By courtesy of Roche Diagnostics GmbH.
Source: Linde-KCA-Dresden GmbH
Project
Customer
Cell system
genetically modified
Year
Investment
value million €
Engineering Start
MAB – monoclonal
antibodies
F. Hoffmann-La Roche AG
Mammalian cells
2004
250
Concept
EPO
Roche Diagnostics GmbH
Mammalian cells
2003
50*
Concept
Coagulation factor,
Kogenate
Bayer AG
Mammalian cells
2000
200
Concept
Insulin Lantus
Aventis Pharma GmbH
Bacteria, sequence-
2000
150
Basic
1998
10
Process development
Start Linde project
Determination
of basic process data
modified Insulin gene
Hepatitis B vaccine
Rhein Biotech
Yeast
** Without building
35
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Genetically modified cell systems
A donor and a host cell are the basis for the generation of genetically modified cell systems by the technique of recombination.
The donor cell supplies the genetic information – the gene – for
production of the desired drug substance in the form of a DNA
fragment. The host cell – normally a bacterial or mammalian cell has two functions: Firstly, it acts as source of the vector DNA fragment for recombination with the DNA fragment of the donor cell
and secondly, as carrier of the recombined genetic information.
The host cell must in addition be capable of growing in culture
and producing the desired drug substance on the basis of the
new genetic information under defined conditions. Creation of
these conditions is one of the tasks associated with the design of
biotechnological plants. (in this connection, see Figure 2)
Monoclonal antibodies (MABs)
Antibodies are proteins produced by the human body and in their
simplest form have the shape of a Y.
The two arms in the upper part enable the antibody to
recognize a foreign structure (e.g., an invading virus) and to
attach itself to it. The lower section of the Y is able to alarm
our immune system. The body’s defense system is thereby
activated and the foreign structure to which the antibody has
attached itself is destroyed.
Antibodies are one of the main weapons of our immune
system. Anyone is aware of vaccinations against tetanus (lockjaw), polio (poliomyelitis) or hepatitis B. Vaccination causes
antibodies against invading disease germs to be formed in our
body. Antibodies continually roam the bloodstream as detectors
and in this way are able to identify and mark bacteria and viruses
quickly.
Antibodies have the function of marking everything that is
foreign to our body, thus classifying it as an enemy. Cancer cells
in the human body can also be recognized by antibodies and
marked for eradication by the immune system. Modern cancer
therapy with monoclonal antibodies (monoclonal = deriving from
one cell clone) makes use of this mechanism. Like a key fitting
exactly in a lock, monoclonal antibodies attach themselves to an
exactly matching site on the foreign object. Drugs that selectively recognize cancer cells and initiate their destruction are
already on the market.
The cancer drug Avastin ® (bevacizumab) is also based on
monoclonal antibodies. However, here the antibodies capture a
growth factor for blood vessels and eliminate it. Tumors produce
larger amounts of this growth factor, thus stimulating the growth
of blood vessels which supply the continually increasing mass of
cancerous tissue with blood. If the growth factor is eliminated,
tumor growth is no longer supported.
Source: Quotation taken from Dr. Armin Plaga in “Der Pillendreher,”
employee magazine of F. Hoffmann-La Roche AG, issue of June 2004
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Active pharmaceutical ingredient (API)
Active pharmaceutical ingredients are drug substances that are
developed and produced by chemical or biotechnological syntheses as therapeutic treatment options for selected diseases.
APIs are prepared as finished pharmaceuticals suitable for
application, such as tablets, sprays, ointments, etc. The finished
pharmaceuticals ensure the exact dosage and the desired profile of action, i.e., timed release of the drug substance in the
human body.
Erythropoietin (EPO)
Erythropoietin (EPO) is a hormone, which is important for the
formation of red blood cells. Healthy individuals produce
sufficient quantities of this hormone primarily in the kidney,
whereas persons seriously ill with renal disease and cancer
patients, especially after chemotherapy, frequently suffer
from a deficiency of EPO. Today they can be treated with EPO
produced by genetically modified mammalian cell cultures.
The drug substance, EPO, is a macromolecule with a complex
molecular structure and folding pattern. It consists of a protein
chain composed of 166 amino acid to which a total of four carbohydrate chains are attached. During production, it must be
ensured that the molecular and structural identity of the drug is
maintained.
With annual sales in the 10 billion-dollar range (see Table 1),
EPO is one of the economically most important biotechnologically
produced pharmaceuticals. In February 2003 Linde-KCA-Dresden
GmbH received an order from the pharmaceutical company
Authors
37
Roche Diagnostics GmbH for the design of a cell culture plant for
EPO production in the Bavarian city of Penzberg. Today, design of
the plant has been successfully completed.
CHO cells
There are now a large number of cell lines available that have
been derived from organs of a variety of mammals. CHO cells
(Chinese hamster ovary cells), which were originally isolated in
the oophoron (ovary) of the Chinese hamster for basic research
purposes, have become established as the standard system
for biotechnological production. These cells are very well characterized in terms of cell and molecular biology, and reliable
methods exist for their genetic modification. CHO cells are
“immortal,” i.e., they can be propagated ”in vitro“ as a so-called
permanent cell line. In addition, they are capable of growing
in suspension, which is a decisive advantage for production on
a large scale. CHO cells are used whenever “sophisticated”
proteins, by which bacteria are “overstrained” with respect to
size and structure, have to be produced. This is particularly
appropriate for proteins which are normally modified following
their biosynthesis in higher organisms by cell-specific systems,
for example by attachment of complex carbohydrate chains
(see EPO). This modification is essential for the specific function
in the human body and hence also for action as a drug.
Dr. Hans-Jürgen Maaß
Dr.-Ing. Hans-Jürgen Maaß has been working at Linde-KCADresden GmbH as Division Manager for Pharmaceutical
Plants since 1992. In this position he is also responsible for
market analyses, extension of the technology profile and
introduction of innovative processes.
Dr. Karin Bronnenmeier
Dr. rer. nat. habil. Karin Bronnenmeier has been Senior Process Biologist at Linde-KCA-Dresden GmbH since 2001. She
works there in business development for pharmaceutical
plants with emphasis on biotechnology. Before joining LindeKCA, Dr. Bronnenmeier was active in basic biotechnological
research as Research Group Leader for ”Molecular Enzymology” at the Technical University of Munich, where she
was qualified as university lecturer. During this period she
published more than 60 scientific papers in the field of
molecular biotechnology.
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Heinz V. Bölt and Dr. Peter M. Fritz
First Application of a New Process for Producing Linear Alpha-Olefins
Base Stock for Plastics and Detergents
They are used to make shopping bags, detergents or lubricants: linear alpha-olefins (LAOs)
have many applications in the chemical industry. They have a broad range of hydrocarbons
of different lengths, based on a single molecule: ethylene. Linde, with the Saudi-Arabian
company SABIC, has developed a technologically simple and particularly economical process for producing LAOs, which is now realized in a commercial plant.
Plastics or plasticizers, polishing agents, detergents or candles:
the linear alpha-olefin (LAO) group is the basis for an entire
series of products (Figure 1). From the chemical viewpoint, they
are linear hydrocarbons having a double bond between the first
and second carbon atoms (Table 1). Thus the double bond is in
the alpha position, giving the linear alpha-olefins their name.
LAOs are produced primarily through “oligomerization” of ethylene.
Combining two or more ethylene molecules gives hydrocarbon
chains of various lengths, always having an even number of
carbon atoms:
C4 = 1-butene, C6 = 1-hexene, C8 = 1-octene, C10 = 1-decene, etc.
With the ·-SABLIN® technology, it is possible to produce LAOs
particularly economically with a simple reactor design and a
new type of catalyst system. ·-SABLIN® was developed by Linde
Engineering in cooperation with the Saudi-Arabian company
SABIC (Saudi Arabian Basic Industries Corporation). The first
world-scale commercial plant is now being built for one of the
SABIC subsidiaries.
Applications of linear alpha-olefins
LAOs are used to produce various products, depending on their
chain lengths. Short-chain LAOs (C4 to C8) are used primarily as
comonomers in producing polyethylene. Medium range LAOs
(C8 to C12) are raw materials for producing synthetic lubricants.
LAOs in the range of C12 to C18 are used to produce detergents,
and the long-chain LAOs (C18+) can be used directly as lubricants
and drilling fluids.
Use of LAOs as comonomers for producing polyethylene
has the greatest market share, 50% (Figure 2). Insertion of the
LAO molecules into the long molecular chain of polyethylene can
intentionally change the physical properties of the polymer, so
that polymers with very different product characteristics can be
produced. Up to 20% of 1-butene, 1-hexene or 1-octene are used
in modern polymerization processes.
As the plastics market has been growing for years, the
comonomers are the driving force for the continually growing
need for LAOs (Figure 3). The predicted growth rate for LAOs,
5 to 10% , is above that for all but a very few other chemical
intermediates.
Development of the ·-SABLIN® technology
As none of the long-established processes are available for licensing, Linde started to develop its own technology to produce
LAO in 1993. In the Institute for Chemical Physics (ICP) in Chernogolovka, Russia, Linde found a competent cooperation partner
which already had many years of experience in ethylene oligomerization. After development of the fundamentals of the
process, the project was continued after 1997 with the Saudi
Basic Industries Corporation (SABIC). A pilot plant was built and
the technology was further developed to be ready for marketing.
Today, SABIC and Linde hold all the rights to the technology,
which now has the name ·-SABLIN®.
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39
Figure 1: Applications of alpha-olefins.
Chain length (number of Carbon atoms)
4
6
Plasticizers
8
10
12
Detergents
Polyethylene comonomers
Polybutylene
14
16
18
Shampoos
20-24
24-28
Polishing agents
30+
Candles
Plasticizers
Sticks
Synthetic lubricants
PVC
lubricants
Vinyl acetate copolymers
Oil-soluble lubricants
Vinyl chloride copolymers
Paper treatment
Copolymers with maleic anhydride
Table 1: Names, structures and properties of linear alpha-olefins.
Name
1-Butene
1-Hexene
1-Octene
1-Decene
1-Dodecene
1-Tetradecene
1-Hexadecene
1-Octadecene
1-Eicosene
Empirical formula
C 4H 8
C6H12
C8H16
C10H20
C12H24
C14H28
C16H32
C18H36
C20H40
Structural formula
CH3-CH2-CH=CH2
CH3-(CH2)3-CH=CH2
CH3-(CH2)5-CH=CH2
CH3-(CH2)7-CH=CH2
CH3-(CH2)9-CH=CH2
CH3-(CH2)11-CH=CH2
CH3-(CH2)13-CH=CH2
CH3-(CH2)15-CH=CH2
CH3-(CH2)17-CH=CH2
Molecular weight
56
84
112
140
168
196
224
252
280
Boiling point °C
-6.2
63.5
121.3
170.6
213.3
246
280
308
326
Melting point °C
-185.3
-140.0
-102.7
-66.6
-33.6
-13.0
+4.0
+28.5
+36.8
C4 = gas; C6 to C18 = liquid; C20 to C30+ = colorless wax
Figure 2: Market shares and growth rates of alpha-olefin derivatives.
Market shares
Average annual growth rates (1998 – 2005)
Other 4%
Plasticizers 6%
Polymers 7.5%
Polymers 50%
Lubricants 15%
Other 7.5%
Detergents 2.8%
Lubricants 8.6%
Detergents 25%
Plasticizers 2.7%
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First application of a new process for producing linear alpha-olefins
Figure 3: Growth of demand for alpha-olefins.
1000 tons per year
3500
3000
2500
2000
1500
1000
500
0
1996
1998
2000
2002
2004
Lubricants
Detergents
Plasticizers
2006
2008
2010
Year
Polymers
Other
Figure 4: Schematic diagram of reaction pathway for ethylene oligomerization in the ·-SABLIN® process.
Al
1-Hexene
Al/Zr
Zr
Ethylene
H2C = CH2
H2C = CH-CH2-CH2-CH2-CH3
CH2-CH3
Al/Zr
Ethylene
H2C-CH2-CH2-CH3
Ethylene
H2C = CH2
H2C = CH2
Al/Zr
H2C-CH2-CH2-CH2-CH2-CH3
Al
Al component
Zr AlZr component
Figure 5: Views of the ·-SABLIN® pilot plant at the
Al/Zr
Active catalyst
Figure 7: Principle of the ·-SABLIN® LAO reactor.
SABIC R&T center at Riyadh, Saudi Arabia.
Ethylene
Light LAOs
Condenser
Catalyst
Solvent
Ethylene
Heavy LAOs
Catalyst
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Figure 6: Typical analyses of 1-butene and 1-hexene from the ·-SABLIN®pilot plant.
1
1
4
2
3
4
6
3
2
5
7
*
5
/1/
/2/
/3/
/4/
/5/
1-butene
n-butane
trans-2-butene
cis-2-butene
iso-C4
Percent by weight
99.500
< 0.010
0.200
0.300
< 0.001
No detectable dienes, acetylene, etc.
/1/
/2/
/3/
/4/
/5/
/6/
/7/
/*/
Percent by weight
1-Hexene
98.23
trans-3-Methyl-2-pentene
0.25
n-Hexane
0.27
trans-2-Hexene
0.41
cis-3-Methyl-2-pentene
0.14
cis-2-Hexene
0.39
cis/trans-4-Methyl-2-pentene
0.16
C6-olefin
0.13
No detectable dienes, acetylene, etc.
The cooperation with SABIC had the following objectives:
–– Optimization of the catalyst system and of the operating
conditions
–– Reactor modeling and reactor design
–– Construction and operation of a pilot plant
–– Development of models and tools to scale
up the technology.
The development of the ·-SABLIN® technology was concluded
in 2001 with the successful operation of the pilot plant and
release of the technology for licensing. In 2002, Linde began
planning and construction of a world-scale ·-SABLIN® plant for
Jubail United Petrochemical Company (UNITED), a subsidiary of
SABIC. This first commercial plant will be completed in 2006.
Basic Chemistry
The addition reaction of olefins to form dimers, trimers, etc.,
is called “oligomerization”. If ethylene is used, the products
are linear alpha olefins. The ·-SABLIN® process uses a twocomponent catalyst system: a patented zirconium compound
and a commercially available aluminum alkyl as the co-catalyst
(Figure 4). The reaction conditions can be kept moderate at
20 to 30 bar and 60 to 100 ºC. Chain growth and chain termination
occur in the same reactor, so this is a single-step system. Chain
growth and termination are determined by the molar ratio of
aluminum (Al) to Zirconium (Zr). Thus, it is possible to get the
desired product distribution by simply adjusting the amounts of
catalyst and co-catalyst. With a high Al/Zr ratio, for instance, one
can produce a product mixture that contains 80% C4 to C8 LAOs.
The active catalyst complex is characterized by high activity
and selectivity. Up to 20 tons of LAO products can be produced
with one kilogram of the zirconium compound.
In contrast to the ·-SABLIN® technology, the established
processes operate at substantially higher pressures (up to 200
bar) and higher temperatures (up to 300 ºC). Some of them are
based on the Ziegler reaction, in which triethylaluminum, for
instance, is used as the starting material for the catalyst system.
With the other processes, other reaction steps such as isomerization and metathesis are sometimes applied, in addition to the
oligomerization reaction, to get the desired product distribution.
Like the ·-SABLIN® technology, all the processes operate exclusively in the liquid phase with a solvent, or use the products
formed as solvents.
41
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The ·-SABLIN® pilot plant
After intensive laboratory tests, SABIC and LINDE started work
on the engineering of the ·-SABLIN® pilot plant in 1998. The
plant modules were assembled at Linde Engineering and then
shipped to SABIC Research & Technology at Riyadh. There, they
were incorporated into the existing pilot plant infrastructure.
The plant was successfully put into operation in the spring of
2000 (Figure 5).
The pilot plant is designed for a maximum reactor throughput
of 15 kg/h (including the solvent). That amounts to a LAO capacity
of about 50 tons/year. The reactor geometry resembles a representative segment of a commercial reactor, so that it is suitable
for testing scale-up methods and tools. Aside from the complete
reaction section, the pilot plant has a separation section to fractionate the reaction product into typical product cuts, as well as all
recycles (e. g., ethylene, solvent). The ratio of the Zr catalyst to the
Al co-catalyst can be varied over a wide range in the reaction
section.
Operation of the pilot plant provided ample operating experience
on an industrial scale. That involved the following points in particular:
–– Production and qualification of representative LAO products
for specific applications (see Figure 6).
–– Confirmation of catalyst and reactor performance with respect
to activity, selectivity, and productivity; determination of the
optimal reaction conditions and recycles.
–– Demonstration of catalyst deactivation and catalyst removal.
–– Confirmation of the material concept for the reactor section
and the separation section.
–– Tool for trouble-shooting of commercial LAO plants.
The LAO reactor concept
Oligomerization of ethylene to linear alpha-olefins occurs by
homogeneous catalysis in a bubble column reactor, with the
solvent and the catalyst components, which are also liquid, fed
into its 2-phase layer (Figure 7). Ethylene is introduced via a
gas distribution system to the bottom section. The long-chain
alpha-olefins and the solvent are removed from the reactor by
means of a side drawoff from the two-phase layer. The shortchain alpha-olefins and excess ethylene leave the reactor
through the reactor overhead, corresponding to the thermodynamic phase equilibrium.
Part of the alpha-olefins formed and part of the solvent are
condensed in an integral condenser and serve as internal reflux.
The ethylene feed to the LAO reactor provides the raw material
for the oligomerization reaction, and provides intense mixing of
the 2-phase layer. As the oligomerization is a strongly exothermic
reaction, the ethylene also acts as a cooling agent to remove the
heat of reaction from the LAO reactor.
The function of the ethylene as a coolant is one of the
characteristic and unique features of the ·-SABLIN® technology.
With this function, it is possible to avoid using externally cooled
heat exchanger tubes connected to the reaction system, which
would be prone to fouling and plugging by even traces of polymerization.
In the ·-SABLIN® LAO reactor, on the other hand, the heat
of reaction is removed by the circulation of ethylene through the
reactor by heating the ethylene. A smaller portion of the heat of
reaction is also removed from the 2-phase layer by evaporative
cooling and by reflux of cold solvent to the reactor. Cooling systems
needing regular cleaning are not required.
Another important function of the ethylene circulation is
that of effective and homogeneous mixing of the reaction mass
in the 2-phase layer. Assurance of a homogeneous reaction
mass is particularly important to avoid local hot spots that would
degrade the product qualities.
Reactor modeling
A reactor model was prepared as part of the development work
for the ·-SABLIN® technology. It is being used as a versatile tool
for technology optimization and reactor design. With this reactor
model it is possible to predict product distributions, to determine
the optimal operating conditions for the desired distribution, and
to establish the reactor geometry.
The basis of the reactor model is a kinetic model of the fundamental reactions. The basic equations for the reactor kinetics
were determined in cooperation with well-known technical
universities. Aside from the mass and energy balances and the
fluid dynamic relations, a closed mathematical model of the
bubble column reactor, including the reflux condenser, was
established. Further studies on the following issues were done
to prove the validity of the model computations:
–– Physical and chemical properties of the reaction partners
–– Thermodynamic properties of the components
–– Hydrodynamic characteristics.
Extensive tests in laboratory plants and in the pilot plant, as well
as experience from comparable technologies provided the bases
for a reliable reactor design.
Separation of the LAOs
The heavy (long-chain) alpha-olefins, with the solvent and the
dissolved catalyst are removed from the 2-phase layer of the LAO
reactor in liquid form in a side-drawoff. In the next step, the catalyst
components still contained in this stream are deactivated and
separated from the alpha-olefins (Figure 8). Then the LAO fraction
after catalyst removal, together with the fraction of light (shortchain) alpha-olefins is sent to C2/C4 separation. Part of the overhead product from this column is returned to the LAO reactor in
the ethylene cycle. To prevent accumulation of inert components
in the ethylene loop, a small volume is removed from the loop as
the “C2 purge”. The bottoms from the C2/C4 separation are sent to
further fractionations, in which they are separated into the desired
end products. The solvent is also recovered in the separation
section and returned to the LAO reactor.
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Figure 8: Typical separation section of a LAO plant.
1-Butene
Solvent recycle
1-Hexene
C2 purge
Overhead product
Ethylene circulation
LAO reactor
1-Octene
Catalyst
removal
1-Decene
Catalyst,
ethylene
C4+
Bottom product
Figure 10: Typical view of a LAO plant.
C8+
C12+
43
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Figure 9: Material balance of a plant for production of 200,000 tons of LAO per year.
Ethylene 213,333 tons per year
Alpha olefin plant
C2 purge
13,333 tons per year
1-Butene
1-Hexene
1-Octene
1-Decene
C12 - C18 LAO
C20+ LAO
Total
Only conventional distillation technology is used in the entire
product separation process. Other expensive purification steps
for the products are not required, since the catalyst produces
directly high-purity alpha-olefins.
Figure 9 shows an overall material balance for a plant producing 200,000 tons of alpha-olefins per year. In this example, the
focus for the product distribution to meet the needs of the client
is at short-chain alpha-olefins (1-butene, 1-hexene and 1-octene).
The net production of alpha-olefins is 200,000 tons per year.
Figure 10 shows a typical view of a commercial LAO plant.
Technical and economic advantages of the
·-SABLIN® technology
Most of the established LAO technologies are characterized by
catalyst systems with relatively low activities and by industrial
plants that allow only suboptimal reaction conditions. Technologies
based on the Ziegler chain growth reaction, with aluminum
alkyls, require very high ethylene pressures (more than 200 bar)
and high temperatures (more than 300 ºC). The reaction pressure
can be reduced if nickel-phosphane / boro-hydride systems are
used, but then the molecular weight distribution range of the
LAO products becomes broader. Furthermore, the established LAO
technologies are generally not available for licensing. Those
points were the initial basis for development of the ·-SABLIN®
technology with the objective of being able o produce LAO in a
competitive process independently of the established manufacturers and technologies.
5,332 tons per year
The technical and economic advantages of ·-SABLIN® can be
summarized as follows:
Reaction pressure and temperature
Use of moderate reaction conditions (20 to 30 bar and 60 to
100 ºC) provides a significant reduction of capital costs for the
oligomerization reactors and of the operating costs of the
plant. Another advantage of these moderate reaction conditions
and of the highly selective catalyst system is the extremely
low formation of polymers in the oligomerization reactor.
Catalyst deactivation at high temperatures
The ·-SABLIN® catalyst is thermally destroyed at temperatures
above the normal reaction conditions. Therefore, the reaction
cannot get into the region of highly exothermic and almost
uncontrollable polymerization, even under abnormal operating
conditions, and no state that is undesirable for plant operation
and critical for safety is reached.
High product purities
As a consequence of the highly active and highly selective
catalyst system, undesired byproducts such as polymers and
non-alpha-olefins are hardly formed at all. Further purification
steps such as superfractionations or extractions are not required
for production of the desired product fractions.
Plant flexibility
The desired product distribution can be adapted easily in
practical plant operation to meet the current market requirements
by variation of the ratio of catalyst to co-catalyst.
High economic efficiency
The moderate reaction conditions, the highly selective catalyst
system and the ability to use mainly carbon steel in wide areas
allow realization of a plant with attractive capital costs and
optimized utility requirement. The catalyst components used
consist of raw materials that are readily commercially available.
Because of that, the LAO producer is independent of specific
catalyst manufacturers.
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Well-proven plant design
For the ·-SABLIN® technology the following references
are available:
Laboratory plants at Linde and SABIC: Different types of laboratory plants (batch plants as well as continuous plants) at Linde
and at SABIC have been operated for many thousand hours.
LAO pilot plant: The LAO pilot plant at the SABIC R&D facilities in
Riyadh was operated for several years to optimize and demonstrate
the technology, as well as to produce representative product
fractions in technical quantities, which were then used to qualify
them in polyethylene plants.
Linde olefin plants: The reference list of Linde olefin plants
(ethylene plants, steam crackers) built by Linde in recent decades
includes more than 30 world-scale plants. All those plants include
a fractionation section for the separation of components similar
to the separation section of a LAO plant. As a consequence, the
full expertise and experience from design and operation of all
these olefins plants is utilized for the design and operation of the
separation section of a LAO plant.
Commercial LAO plants: Linde has previously designed and built
several commercial LAO plants for SASOL in South Africa, to
recover alpha-olefins from Fischer-Tropsch condensates. The first
commercial LAO plant based on the ·-SABLIN® technology is
being built by Linde for Jubail United Petrochemical Company
(UNITED) in Saudi Arabia. Start-up for that plant is planned for
2006.
The authors
Dr. Peter M. Fritz
Dr. Peter M. Fritz studied chemistry at Mainz and
Munich. He has been employed since 1988 in
research and development at Linde AG, Linde
Engineering division, Höllriegelskreuth, Munich. In
the following years he participated in development
of the Linde propane dehydrogenation technology.
He was also employed world-wide in start-up and
test runs of pilot plants and commercial plants. In
1998, Dr. Fritz became Project Manager for research
and development cooperation with SABIC. In that
assignment, he worked regularly for several years
in Saudi Arabia on start-up and subsequent test
operations of the ·-SABLIN® pilot plant. At present,
Dr. Fritz has been assigned to LKCA at Dresden,
where he is supporting the engineering for the first
UNITED ·-SABLIN® plant as part of the SABIC-Linde
licensor team.
Abstract
Linear alpha-olefins (LAOs) have many applications as intermediates in the chemical industry. Linde, in cooperation with the
Saudi-Arabian company SABIC (Saudi Arabian Basic Industries
Corporation), has developed a new technology for selective
catalytic synthesis of LAOs from ethylene. The ·-SABLIN® technology can be used to produce a wide range (short to long chains)
of highly pure LAOs with high selectivity and under moderate
operating conditions. The product distribution can be changed
easily by varying the reaction conditions and adjusting the
homogeneous catalyst system. The ·-SABLIN® technology was
tested successfully over several years in a pilot plant at the SABIC
Research and Technology Center in Riyadh, Saudi Arabia. The first
commercial plant using the ·-SABLIN® technology is being built
by Linde for Jubail United Petrochemical Company (UNITED) in
Al-Jubail, Saudi Arabia. It will begin commercial production in 2006.
Heinz V. Bölt
Dipl.-Ing Heinz V. Bölt studied industrial physics, and became
an employee of Linde AG, in the Linde Engineering division at
Höllriegelskreuth at Munich in 1975. In the following 12 years
he worked in many world-wide projects and contracts as a
process engineer in the area of olefin plants. In 1987 he became
Project Manager for development of Linde propane dehydrogenation technology. In that appointment he managed
construction and operation of the dehydrogenation pilot plants
at Ludwigshafen and at Statoil in Mongstad, Norway. Since
1993 Mr. Bölt has also been involved in development of other
petrochemical technologies, particularly the alpha-olefins
technology. At present, he is Manager Technology Development Olefin Plants, where he is responsible for coordination
of development work at Linde, cooperation with external
development partners and design of commercial plants based
on developmental results, as well as appropriate support of
Sales in marketing of the new technologies.
45
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Seite U4
ISSN-1612-2232
Linde AG
Abraham-Lincoln-Strasse 21
65189 Wiesbaden
Germany
Tel. +49.611.770-0
Fax +49.611.770-603
www.linde.com

Linde Technology 2/2004

Transcription

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