Outotec® Filtration solutions

Transcription

Outotec® Filtration solutions
Sustainable filtration solutions
Outotec is a leading innovator, developer and supplier
Efficient filtration solutions

Simplified processes
the process industries utilizing wet-processing in their

Reduced production costs
production. From copper mines to food manufacturing,

Reduced environmental impact
and from traditional to emerging applications, Outotec’s

Increased safety at work
full-service approach and process expertise help

Improved product quality
of solid-liquid separation products and solutions for
customers achieve their performance and sustainability
targets.
002 Outotec filtration solutions
A committed partner from the start
Outotec operates globally through an extensive network
Outotec provides world-leading technologies and
of sales and service centres. Outotec provides its
technology selection expertise based on laboratory
customers with an unrivalled combination of process
test programs, feasibility studies, basic and detailed
expertise and services and focuses on developing its
engineering, technology specific equipment supply,
capabilities, products, solutions and services for the
training, erection supervision and start-up assistance,
mining, metallurgy and chemical process industries.
as well as follow-up and technical support services. Such
Outotec strives to build a long-term relationship with
involvement, from a single partner, offers customers
its customers, ensuring that they receive the very best
the possibility to enhance the production processes and
solutions for their operating environment. Outotec offers
minimize operating costs throughout the lifetime of the
a comprehensive Performance for Life service concept
plant.
for its filtration solutions. Outotec's early involvement
in projects ensures the most profitable and competent
solutions.
Outotec offers

Innovative and proven technologies

Laboratory test programs and
pilot test campaigns

Feasibility studies

Proprietary and key equipment supply

Commissioning and start-up services

Process automation

Spare parts and maintenance services

Plant audits, retrofits and machine
upgrades
Outotec Thickeners, Clarifiers and Filters the perfect combination
Outotec filtration solutions 003
Caring for the environment
Outotec filtration technologies are designed to minimize
Efficient solid-liquid separation technology leads to
environmental impact. We strive to make effective use
both economical and environmental benefits. Outotec
of raw materials, minimize the production of stable
Larox filters and filtration solutions are designed in
or re-usable residues and reduce water and energy
such a way that in most of the processes they help
consumption.
to achieve significant savings in energy and/or water
Outotec Larox® filters and filtration solutions help
customers meet growing environmental requirements
and tightening environmental legislation. In addition to
consumption. Efficient filtration also leads to better
quality waste water, thus reducing the environmental
burden.
savings in energy and water, the amount of waste and
other process emissions can be significantly reduced.
Positive environmental impact
reduced water waste
improved energy use
reduced fume and dust emissions
less solids waste
Testing Application
Consulting
Engineering
New Equipment
Start-Up
Maintenance
Modernization
Refurbishment
Filtration solutions and technologies
Outotec Larox filters are built to last, delivering
Vacuum filtration

Capillary Action Filters
best process results at the optimum operating cost for

Horizontal Vacuum Belt Filters
a wide range of processes and process environments.

Disc Filters
maximum production performance, availability and the
Over pressure
The broad product range includes filters and solutions
based on different filtration principles, available in a
wide variety of sizes, capacities and related services,
all performing in the toughest operating conditions.
A wide range of test filtration solutions and high-tech
automation systems are also available.

Automatic Pressure Filters

Filter Presses

Automatic Polishing Filters
Relocation &
Resale
In-depth application and
process know-how
Efficient solutions for mining and
metallurgy
Many of the world’s largest and best known mining
to mining operations and their associated mineral
operations use Outotec Larox filters. Decades of
processing plants for decades. With the ever increasing
experience and continuous investment in research and
scale of operations and the diminishing availability of
development place Outotec at the forefront in meeting
water, Outotec continuously develops new filtration
the filtration needs of mineral concentrators. Smelters
solutions to deliver the required process performance
and refineries are complicated processes requiring a
with safe and reliable equipment.
diverse range of filtration solutions. The separation
of solid and liquid substances has become a critical
process in the continuous evolution of refineries
towards more efficient processing of valuable metals
as well as achieving high purity requirements from
their customers. With a large and established reference
base, Outotec has been the recognized filtration supplier
Ferrous mining operations
Non ferrous mineral
processing
Smelting, hydrometallurgy
and light metals
Iron ore
Base metal concentrates
Precipitates, products and
Chromite
Precious metals
Mine tailings
Coal
Process solution purification
Kaolin
Alumina
Talc
Lithium
Market leader in high capacity
filtration
GCC
residues washing and filtration
Market leader for filtration in
Market leader in pressure
lateritic nickel processing.
filtration of flotation concentrates
Industry benchmark for
purification of copper electrolytes
Trustworthy partner to chemical processing
Technological progress is particularly rapid in the
generates major cost-savings and improvements in
chemical process industries (CPI). The Chemical
the production process. Outotec has gained a strong
Process Industries face ever-increasing demands such
reputation as a truly reliable solution provider in this
as - saving energy, conserving valuable resources
industry sector, where absolute trust and confidentiality
and improving productivity and quality as well as stiff
between business partners is a necessity.
competition and consolidation.
Outotec is committed to helping you
With over 50 years of filtration experience and over
1000 filtration solutions delivered into CPI applications
worldwide, Outotec has proven to help its CPI customers
succeed in this challenging business environment.
Reduce lifetime production costs
Improve product quality, value and consistency
Improve safety, health and environmental
performance
Combining Outotec’s technical know-how with the
customer’s own chemical and process expertise
Improve product yield
Pigments and fillers
Food, pharma and
bio processes
Energy, environment and
general CPI
PCC, TiO2 and silicates
Starch and sugars
Sulphur removal and Industrial
Toner, organic pigments, dyes
Edible oils
and ink
Market leader in filtration of
zeolites and pressure filtration
of PCC and proven supplier for
chemically produced toner
wastes
Vitamins and amino acids
Polymers, resins and plastics
Fermentation broth and drug
Pulp and paper lime mud
intermediates
Cellulosic bioethanol and
lignin
and dregs
Industrial wastes
Proven environmental solution
Market leader in pressure
for filtration of fly ash and green
filtration of starches
liquor dregs
Outotec Larox® PF
Automatic pressure filters
Outotec Larox automatic pressure filters have been
developed to meet the needs of industry. Outotec
Larox automatic pressure filters are recessed
plate membrane filters in which the chambers lie
horizontally.
Outotec Larox automatic pressure filters deliver
superior process results
Exceptionally dry filter cakes to meet TML and
reduce transport and drying costs
Ability to dewater fine and difficult to dewater solids
Horizontal filter plates without stay bosses produce
homogenous cakes and provide efficient cake
washing
Moving filter cloth guarantees complete cake
discharge, and simultaneous cloth washing
prolongs cloth life and performance
High unit capacity and vertical construction reduce
both the number of filters required and the footprint
Outotec Larox PF filtration area is available from 1.6 to
252 m2 (unit weight up to 160 tons)
for installation
Improved process economy
Every Outotec Larox pressure filter features
energy-efficient production technology, lowering
energy costs and cutting emissions to the lowest
level
Fewer, larger filter plates reduce the number of
components requiring maintenance
Cloth management system
Robust construction and materials for arduous
operating conditions
Fully automatic operation
Automatic operation saves manpower by
Benefits

Excellent dewatering efficiency

Improved product quality and consistency

Fully automatic cake discharge

Low energy consumption

Maximum availability

Reduced lifetime production costs

Improved safety, health and
environment performance
eliminating the need for continuous supervision
Fully automatic operation, not just automated
functions
The Outotec automation system maintains
consistent throughput and performance even with
variable mineralogy or process conditions
Slurry
Slurry
Slurry
Pressing
Pressing
Pressing
Filter
Filter
cloth
cloth
Filtrate
Wash
Wash
liquid
Washliquid
liquid
Filtrate
Filtrate
Wash filtrate
Air
Air
Air
Wash
Wash
filtrate
Filterfiltrate
cloth
Solids
Solids
Solids
Operating principles
1. Filtration
The process slurry is pumped into all filter chambers
simultaneously. The solids begin to form as the filtrate
is displaced by more slurry entering the chamber. As the
solids build, the pumping pressure increases, and filtrate is
forced through the cloth until the required solids thickness
is achieved.
1. Filtration
2. Diaphragm pressing I
High-pressure air or water automatically inflates the
diaphragm located at the top of each chamber, reducing the
chamber volume and squeezing the solids to remove more
filtrate. The solids filtration process and tightly woven filter
cloth produces exceptionally clear filtrate. The high pressure
maximizes filtration efficiency. Diaphragm pressing produces
homogenous dewatered solids of uniform thickness with
minimal excess liquid, which assists the washing and air
blowing steps.
3. Solids washing
Outotec Larox pressure filters can wash dewatered solids
in-situ to maximize solute removal or to recover the mother
liquor with minimal dilution. The wash liquid is distributed
evenly because the solids are homogenous and the filter
plates lie horizontally. The wash liquid flows through the
solids, displacing the mother liquid with minimal mixing.
Slurry
Pressing medium
Filter cloth
Wash liquid
Filtrate
Air
Wash filtrate
Solids
2. Diaphragm pressing I
Slurry
Pressing medium
Filter cloth
Wash liquid
Filtrate
Air
Wash
filtrate
3. Solids
washing
Solids
Slurry
Pressing medium
4. Diaphragm pressing II
Filter cloth
Wash liquid
The diaphragms are re-inflated, forcing the wash liquid
uniformly through the solids. This produces a washing
efficiency of over 95 %, with consistent dry solids quality and
minimum wash liquid consumption.
Filtrate
Air
4. Diaphragm
pressing II
Wash filtrate
Solids
5. Air blowing
Compressed air is blown through the solids for final
dewatering. The moisture content is minimized and can be
controlled precisely by adjusting the pressure and duration
of the air blow.
6. Solids discharge and cloth washing
After the plate pack opens, the dewatered solids are
conveyed out of each chamber on the moving filter cloth. The
integrated wash unit sprays both sides of the cloth with highpressure water, minimizing cloth blinding to ensure consistent
filtration results.
Slurry
Pressing medium
Filter cloth
Wash liquid
Filtrate
Air
Wash filtrate
Solids
5. Air blowing
Slurry
Pressing medium
Filter cloth
Wash liquid
Filtrate
Air
Wash filtrate
Solids
6. Solids discharge and cloth washing
Outotec Larox® FP & FFP
Pressure filters
Outotec Larox FP & FFP pressure filters are widely
used in mining and Metallurgical and Chemical
process industry operations. In mining applications
the trend towards finer grinding in concentrators has
resulted in more difficult dewatering, requiring an
increased use of pressure filtration.
Adaptability to unsteady process conditions and
variable products
Membrane squeezing reduces cycle times and
improves process results. Even if the chamber
is not filled sufficiently due to variations in process
conditions, the filter performance is maintained
Membrane squeezing helps uniform and equalized
build-up of the filter cake and the fixation of the
cake ensures that the required washing time and
quantity of washing liquid are drastically reduced
Higher dry solid content in the filter cake can be
achieved with membrane squeezing, i.e. lower
Outotec Larox FFP filtration area is available from 108 to
energy consumption during cake drying
Easier cake release and a more reliable cake
discharge from the press
Specially designed filter plates allow the use of air
blowing for additional dewatering while minimizing
Benefits
the effects of wear and tear

Short technical times ensure the highest specific
filtration capacity for this kind of equipment
Over 60 years experience (based on
Hoesch design and expertise)

Efficient dewatering and washing
endurance fatigue limit calculations and 3D

Very short cycle times (FFP product line)
modeling, ensure structural integrity

Corrosion resistant designs

Reliable cake discharge

Modern design and Eurocode 3 compliant
Modern design methods, including FEMA,
Compliance with Eurocode 3, EN, ISO, DIN and
most international standards
Outotec control systems automate, optimize and
allow operators to visualize the entire filtration
process
Standardized automation system provides
sophisticated control for even the simplest filter
model in the range
State-of-the-art manufacturing methods,
high-quality components and continuous product
Slurry
Slurry
Pressing
Pressing
improvements ensure that each filter is the best in
Filter
cloth
Filtrate
Wash
Washliquid
liquid
Filtrate
Wash filtrate
Air
Air
Wash
Filterfiltrate
cloth
Solids
Solids
its category
1. Filling and filtration
Slurry is pumped through the feed channel into the filter
chambers simultaneously. During filtration the solids are
captured by the filter cloth on both sides of the chamber to
form a cake with the filtrate displaced through the cloth.
During filtration the cake thickness increases until the desired
solids concentration is reached.
FFP
principles
MFP/CFP
principles (optional)
1. Filling and filtration
2. Cake washing
5. Post-squeezing
3. Pre-squeezing
6. Blow-drying
4. Cake washing
7. Cake discharge
8. Cloth washing
2. Cake washing through the slurry channel (optional)
After filtration the wash water displaces the suspension from
the inlet channel and flows into the chamber. In the chamber,
the washing medium flows in a gap between the filtered cakes
to wash out the mother liquor. Due to the uniform cakes, the
cake wash takes place evenly over the entire filtering area.
3. Pre-squeezing (optional)
Air or water presses the membrane into the filter chamber.
The membrane reduces the chamber volume and squeezes
the filter cakes on each side to form a single cake and to
mechanically remove filtrate.
4. Cake washing through the corner channel (optional)
The washing medium is introduced into the filtrate channels
on the membrane side and penetrates through the cake by
pressure. The wash filtrate leaves the chamber through the
filtrate channels on the chamber side. The pre-squeezing
of the membrane remains on during washing to prevent the
formation of cracks and enhance the washing results.
5. Post-squeezing
The filter cake is dewatered by squeezing with a membrane
at high pressure, which ensures maximum mechanical
dewatering. At the same time, this step prepares the cake for
blow-drying.
6. Blow-drying
Compressed air is introduced through the filtrate channel on
the membrane plates and blows through the cake removing
filtrate to achieve low residual moisture. During blow-drying,
the cake remains under membrane pressure.
7. Cake discharge
Once the filtration sequence is completed the filter is opened
to allow the cakes to drop out of the filter.
8. Cloth washing
To ensure consistent filtration it is often necessary to wash the
filter cloths. This washing can be achieved either by flushing
the plates from a manifold above or by a high-pressure spray
bar that passes between the plates.
Outotec Larox® CC
Capillary action disc filters
Outotec Larox CC
filters ensure high productivity
and superior process results for mining applications.
Efficient
dewatering
and
washing,
competitive
investment costs, low installation and operating
costs, and high environmental and personnel safety
protection.
High operational availability
The dependable, low-maintenance system provides
high availability. The long life sectors and simple
construction require only occasional maintenance
stops and the filters run continuously without the need
of operator intervention.
Environmentally safe
The Outotec Larox CC filter has been designed with the
safety of the environment and personnel in mind. The
filtrate is recyclable, has exceptionally low suspended
Outotec Larox CC filtration area is available from 6 to
solids content and can thus be recycled without
144m2 (unit weight up to 43 tons)
further treatment. Frequent filter cloth disposal is not
necessary.
Low process costs
Outotec Larox CC filters produce extremely dry filter
cakes meeting transportable limits in most cases.
In iron and chromite pelletizing, the consistent low
moisture levels reduce binder additions and create
stronger pellets. Due to the capillary action in Outotec
Benefits
Larox CC filters, energy consumption for dewatering is

No filter cloths
exceptionally low.

Closed-circuit system minimizes water
consumption
Minimal maintenance and high availability
The long life disc construction and few wearing

Thermal drying reduced or eliminated
parts keep maintenance to a minimum. The simple

Minimal ancillaries
construction

Less energy needed

Continuous, efficient cake discharge
with
little
dependency
on
auxiliary
equipment makes the Outotec Larox CC filter operation
the most reliable of any dewatering technology.
Automatic regeneration
The filter plates are automatically regenerated by
backwash, chemical treatment and the ultrasonic
system. No additional cleaning is needed. This
eliminates the need for additional auxiliary equipment
and production downtime.
1. Cake forming
Cake forming takes place on the discs when they rotate
through the slurry. Capillary action creates an extremely high
vacuum level, which draws liquid through the discs into the
filtrate lines. Solids build up rapidly on the external surfaces
of the discs, and the microporous structure prevents any
solids from penetrating the disc surface. The driving force is
generated by a small 2.2 kW vacuum pump.
2. Cake drying
Slurry
Filtrate
Wash liquid
Solids
1. Cake forming
As the discs rotate, capillary action continues in an
uninterrupted manner across the disc surface until all free
liquid is removed from the solids. No air penetrates the disc
surface. The result is an exceptionally dry cake at a fraction
of the energy required by conventional filtration techniques.
Cake washing (optional)
Wash liquid is sprayed evenly and gently on the cake solids.
This process removes additional filtrate or impurities and
achieves a true displacement wash. High wash efficiency is
reached with low liquid consumption. This is a significant
benefit when dewatering concentrates produced in plants
using saline process water.
2. Cake drying
3. Cake discharge
Scrapers remove the cake from the discs. A thin residual cake
is left on the surface to protect against mechanical abrasion.
This reduces maintenance requirements and extends the life
of the discs. Continuous cake discharge is achieved without
the need for a snap blow.
4. Backflow washing
Filtrate is used to flush the discs. It removes residual cake
and cleans the microporous structure. Backflow washing
helps the discs retain their exceptional filtration efficiency and
ensures long, trouble-free life. Backflow washing is automatic
and adjustable for each application.
3. Cake discharge
5. Disc regeneration
Instead of discarding the filter media, ceramic plates can
be regenerated and full permeability returned. Periodic
cleaning is performed automatically with built-in chemical
and ultrasonic systems.
4. Backflow washing
Filter cloth
Slurry
Air
Wash liqu
Pressing
filtrate
Filtrate
Solids
e
Wash filtrate
cloth
Wash filtrate
Slurry
Slurry
Pressing
Filtrate
Filter
cloth
Wash
liquid
Filtrate
Filter cloth
Filtrate
Air
Wash liquid
Slurry
Wash
Solids
Solidsfiltrate
Solids
Pressing
Air
Wash liquid
Wash liquid
Air
Pressing
Solids
Slurry
Filtrate
Wash liquid
Solids
5. Disc regeneration
Outotec Larox® RT and RT-GT
Horizontal vacuum belt filters
Outotec Larox horizontal vacuum belt
filters are
widely used in industry. Outotec Larox RT, and RTGT filters have earned a reputation for delivering
and exceeding requested process performance with
reliability and low operating cost. Outotec Larox
RT and RT-GT filters are used in over 500 different
processes due to their ability to handle a wide range
of feedstocks and produce high purity products at a
very economic cost.
Superior process results
Gravity feed - no pick-up problems when filtering
fast settling slurries
Good cake build up - the cake thickness can be
Outotec Larox RT & RT-GT filtration area is available from
5.6 to 48.4 m2 (unit weight up to 19.2 tons)
varied from 3 mm to over 100 mm
Counter-current washing - outstanding features for
washing coupled with minimum wash liquid
consumption
Flooded washing or spraying possible
The unit operation time is independent of the filter
operation - cake forming, washing and drying zone
lengths are easily configurable
The filter cloth can be washed continuously, thus
providing constant permeability
Multiple unit operations are possible on one
machine
Mother liquid recycling - first fraction containing
fine solids can be returned to be filtered over the
formed cake
Improved process economy
Every Outotec Larox RT and RT-GT filter features
Benefits
cost saving technologies that improve process

Fully automatic
economics

Continuous operation

Excellent washing efficiency

High product quality

Compatible with corrosive applications
tracking system ensure long cloth life

Multiple process steps possible
Robust construction and wide selection of

Low operating costs

Gas tight enclosure (GT)

Solvent processing (GT)

Clean-in-place (GT)
Extremely high product availability coupled with
very low maintenance requirements result in low
operating costs
Continuous cloth washing and patented cloth
construction materials ensure very long filter life
under the most arduous operating conditions
Product description
The heart of the filter is a very simple concept. A continuously
moving filter cloth is supported inside a rigid, profiled movable
vacuum tray (Fig. 1) providing the vacuum area of the filter.
The bottom of the tray is an open grid structure.
The cloth is driven via a head pulley with variable speed drive.
When vacuum is applied beneath the cloth, the frictional grip
created by the vacuum against the cloth is sufficient to move
the tray forward at exactly the same speed as the filter cloth.
The tray therefore moves forward a fixed distance, the vacuum
stroke (Fig. 2), at which point the vacuum is released under
the cloth breaking the frictional grip. The tray is retracted to
its original position, the return stroke, (Fig. 3) the vacuum is
reapplied and the tray again advances with the cloth.
At all times the slurry feed, all cake washes and the cake
discharge continue as normal. Outotec Larox RT filters
therefore provide truly continuous processing.
Fig.1
Fig.2
Vacuum stroke
Continuous cloth advance
Fig.3
Return stroke
Co- and counter-current cake washing
The Outotec Larox RT (Reciprocating Tray) and GT (Gas Tight)
filters offer superior washing capabilities, as an equal vacuum
is applied to every part of the filter surface. Since the cloth is
repositioned on each tray retraction, dead spots in the filter
cake are eliminated. Counter-current cake washing is the
specialty of the Outotec Larox RT and RT-GT filters. With the
capability for up to 15 wash steps on a single filter, extremely
high levels of product purity can be continually achieved using
the minimum possible amount of wash liquid. Reflux washing
and chemical reaction via washing is also possible. The filters
can also be set up with any desired combination of co- and
counter-current washing and can involve more than one wash
liquid, as each liquid can be completely isolated from the
others. Cloth wash liquid can also be recycled back onto the
filter where “water-balance” is an issue.
Continuous cloth advance
Co-current cake washing
Counter-current cake washing
Mechanical dewatering
Hot gas drying
Mechanical dewatering and thermal/hot gas drying
To further decrease cake moisture, it is possible to carry out
various forms of mechanical dewatering and Thermal/Hot
Gas Drying steps on the Outotec Larox RT and RT-GT filters.
Mechanical dewatering options include a Vacuum Seal Belt
(VSB) for filter cakes that crack readily, or a Vacuum Press
Belt (VPB) for cakes that can be compressed while still under
vacuum. Vibration is also offered for thixotropic filter cakes.
For high permeability, low pressure drop cakes where
mechanical dewatering may not be efficient, hot gas drying
offers the ability to dry to extremely low levels, This is
especially true for solvent wetted products dried in the Outotec
Larox RT-GT filter using nitrogen as the drying medium.
The unique segmented tray design makes for an excellent
combination filter-dryer. Using hot gas drying techniques,
residual moisture contents below 0.1 % can be achieved. The
hot gas can be nitrogen or any other inert gas. Cake cooling
can also be carried out after the drying zone to avoid high
discharge temperatures.
Slurry
Slurry
Solids
Solids
Vacuum
Vacuum
Filter cloth
Filter
cloth
Wash
Washliquid
liquid
Air
Air
Filtrate
Filtrate
Wash
Washfiltrate
filtrate
Hot gas
Outotec Larox® RB-SV
Horizontal vacuum belt filters
Outotec Larox RB-SV rubber belt filters meet
the requirements of high capacity, heavy-duty
applications. The filters can handle the highest
capacities, while producing superior performance
in separation, washing and cake dewatering. The
Outotec Larox RB-SV is the result of extensive product
development of the conventional RB filter.
The Outotec Larox RB-SV features vacuum boxes
mounted on one or both sides of the rubber belt. The
side mounted vacuum box(es) offer maintenance and
operational cost benefits versus the conventional RB
design where the vacuum boxes are mounted under
the filter. In addition the Outotec RB-SV filters feature
roller support of the rubber carrier belt. By matching
the roller spacing to the belt rigidity, rollers provide
a stable filtration surface with low friction and power
requirements. The filters can be tailored to provide
Outotec Larox RB-SV filtration area is available from 32 to
the optimum performance. For heavy duties, the
170 m2 (unit weight up to 39,3 tons)
vacuum box can be mounted on each side of the belt,
offering advantages over the conventional rubber
belt concept.
Benefits

High throughput
High level performance

Easier access
Wide range or materials and design options make

Improved cleanliness

Longer belt lifetimes

Excellent process results
the filter suitable to different applications
Continuous filtration
Stable filtration surface
Continuous tracked and tensioned filter cloth
Chemical resistant and long life rubber belt
Various cake discharge systems, according to the
application
Side vacuum box
Accessible cleaning and maintenance
The vacuum box is easily accessible, as it is on the
outside of the filter
The box is stationary, as access for maintenance
and cleaning is via removable panels on the box
The vacuum box acts as the gas-liquid separator,
eliminating the need for separate vessels. Piping
can also be fixed
The overall height of the filter is reduced, as there
is no requirement for space under the belt for
lowering the vacuum box
There are no holes in the center of the rubber belt,
so it can be reinforced across its total width,
thereby increasing belt life
Solid liquid applications
The Outotec Larox RB-SV filter is a continuous vacuum
filter consisting primarily of an endless rubber carrier belt
orientated horizontally along the length of the filter and
controlled by head and tail drive rollers. There are vacuum
boxes located to one or both sides of the belt depending on the
width of the filter or volume of slurry to be filtered.
The vacuum box is configured in sections to match the
required process steps such as dewatering, washing and
drying. Each section has the appropriate size and number of
connections for liquid and air discharge to the corresponding
filtrate receivers.
Side vacuum
Access to the vacuum box for cleaning, adjustment of sections,
maintenance and seal belt replacement is from the side, not
from under the filter.
The rubber carrier belt is supported by a bed of non-lubricated
support rollers and is continuously mechanically driven by an
electric motor with planetary gears. The rubber belt itself
has transversal grooves and perforation holes which in turn
supports the filtration medium (in most cases a woven filter
cloth).
As a result of the continuous movement of the carrier belt and
consequently the filter cloth, the slurry feed, wash liquid(s)
feed, cake drying, cake discharge and cloth washing are
designed to support continuous fully automatic operation.
Cake forming
Cake forming
Slurry is fed to the filter via an adjustable feed distribution
device which contains the required number of feed nozzles
and/or distribution pipes.
The filter cloth, which allows liquid to penetrate and drain
towards the vacuum box, is being transported by the rubber
belt due to the friction between the belt and cloth created by
the vacuum in the transversal grooves.
Cake washing
When cake washing is needed the wash liquid will be fed
through a distribution pipe onto the filter cake via overflow
weir(s). The overflow weirs are specially designed for counter
current washing (solids in filtrate).
Cake drying/discharge
After filtration and/or washing of the filter cake, drying then
takes place by sucking the air through the cake in the last
section of the filter. The airflow through the filter cake reduces
its moisture content to the optimum.
The filter cake is then discharged off the end of the filter. The
nature of the cake determines the type of discharge system –
for example doctor – knife, wire or roller discharge.
Co-current washing
Slurry
Slurry
Solids
Solids
Vacuum
Vacuum
Filter cloth
Filter
cloth
Wash
Washliquid
liquid
Air
Air
Filtrate
Filtrate
Wash
Washfiltrate
filtrate
Outotec Larox® LSF
Polishing filters
Outotec Larox LSF filter is used for the removal and
recovery of solids in low concentration from process
liquids. The quality of the resulting filtrate increases
production capacity while boosting the quality of
plant and refinery products.
Increasing requirements for higher product quality
from metal refineries have resulted in the need for
pure electrolyte streams requiring polishing filtration.
Outotec Larox LSF exploit the phenomena of adsorption
filtration to cause micronic and sub-micronic particles
to adhere to the fibers of the filter media, despite being
small enough to pass through its pores. This activity
reduces particle concentration in the filtrate to almost
undetectable levels.
High quality filtration
Adsorption filtration reduces particle concentrations
to a level of parts per million. Production capacities
increase, as do the quality of plant and refinery end
Outotec Larox PF filtration area is available from 30 to
720 m2 , vessel dia up to 2,6 m (unit dry weight up to 9.4
tons)
products.
Low operating costs
Costly filter aids, such as precoat and body feed, are
Benefits

Very effective dewatering efficiency

Filtrate solids reduced to ppm
solids disposed in the environment. Low electrical

No filter aids needed
energy consumption is another cost-saving benefit,

No moving parts
as the adsorption filtration uses very low pumping

Improved product quality

Reduced lifetime production costs
unneccessary in the vast majority of applications. This
also considerably reduces the volume of total cake
pressures.
Minimal maintenance cost
With no moving parts, the operating cost typically
equates to 1.25 cents (US) per m 3 of filtrate produced.
The unique cloth cleaning and cake discharge system
ensures maximum cloth lifetimes. Normally the filter is
only opened periodically to replace filter cloths.
High capacity, compact and expandable
All Outotec Larox LSF filters occupy little building space.
Automatic (PLC) control of the cloth cleaning and cake
Flow rates as high as 600 m 3 /hr can be consistently
discharge steps at the end of each filtration cycle
handled by a single unit, greatly simplifying the process.
ensures maximum filtration time in subsequent cycles.
Most units are designed with expansion capability,
This also cuts manpower requirements by eliminating
economically
the need for frequent supervision.
requirements.
accommodating
growing
capacity
1. Filtration
During normal operation the slurry is fed into the filter vessel
through the process inlet by a centrifugal pump. All Outotec
Larox LSF polishing filters are rated for process pressures
of 300 kPa and feeding systems are designed to maintain
laminar flow within the vessel to ensure adsorption filtration.
2. Draining
In the beginning of the cloth cleaning and cake discharge cycle
the filter liquid level is drained to the top of the filter elements.
3. Air agitation
In the agitation phase low pressure air is fed to the filtration
vessel through a manifold below the filter elements. This
causes vigorous bubbling and scouring of the filter cake
attached to the filter cloth bag. During agitation the filter
cake is removed from the filter cloth bag, and efficient mixing
causes the filter cake to be re-slurried.
1. Filtration
2. Draining
3. Air agitation
4. Drain with backwash,
wash spray and air
agitation
5. Drain with wash spray
and sluice spray
6. End of the cleaning
activity (cleaning
complete)
4. Drain with backwash, wash spray and air agitation
In this phase the filter vessel is drained through the outlet.
Simultaneously, the filter cloth bags are backwashed and
sprayed on the outside while air agitation continues.
5. Drain with wash spray and sluice spray
During the final draining phase the lower air sparge continues
to keep the re-slurried filter cake in suspension while the
lower sluice sprays direct solids towards the drain outlet,
ensuring complete cake and slurry removal until the filter
vessel is empty.
6. End of the cleaning activity (cleaning complete)
The cleaning sequence is complete, when all cake has been
removed. The unit is ready for filtration.
7. Refilling vessel for filtration (restart)
With cleaning complete and all valves closed, slurry pumping
resumes.
Slurry
Slurry
Wash filtrate
Solids
Vacuum
Air
Slurry
Slurry
Filtercloth
cloth
Filter
Solids
Solids
Wash
liquid
Wash
liquid
Filter
cloth
Filter
cloth
Filtrate
Filtrate
Wash
liquid
Washfiltrate
liquid
Wash
Solids
Vacuum
Vacuum
Air
Air
Filtrate
Filtrate
Wash filtrate
Air
Athmospheric
air
Athmospheric
air
7. Refilling vessel for
filtration (restart)
Outotec Larox® VPF
Polishing filters
Outotec Larox VPF polishing filters are specially designed
to optimize the removal of suspended solids and impurities
before hydrate precipitation utilizing Australian Process
Technology’s proven VPF concept.
Safety
Outotec Larox VPF is safe to operate and maintain. During
filtration and cake removing the completely closed filter
vessel and piping arrangement is sealed and safe from
process liquid splashes. The shell flange is only 1 meter above
the level of the operating platform for easy and safe operation,
inspection and maintenance access.
High quality filtrate
Utilizing the well proven concept, VPF filtration reduces
entrained particulate concentrations to a level of only a few
parts per million. Production capacities increase, as does
the quality of alumina products. These filters can utilize
a wide range of media for filtration depending on process
requirements. Individual leaves can be sampled, checked and
isolated for filtrate clarity.
Low operating and maintenance costs
Low electrical energy consumption is a cost-saving benefit,
as the low flow rate filtration technique uses low pumping
pressures. The filtration cycle is up to 18 hours, so the filter
technical time, including cake sluice and cloth cleaning,
is minimized. The absence of moving parts decreases the
number of wearing parts. The loss of product is minimized by
recovering the content of the filter before the cake removal
phase. In addition, due to the long filtration cycle and low flow
rate, the consumption of the filter aid (TCA) is minimal.
With no moving parts, the operating cost per cubic meter of
produced filtrate is low. The unique cloth cleaning and cake
discharge system together, with integrated caustic washing,
ensures maximum cloth lifetimes.
The unique lid sealing and closing design allows quick and
operator friendly access to the filter leaves, resulting in low
off-line time for media replacement.
Automatic (PLC) control, with the cloth cleaning and cake
discharge steps at the end of each filtration cycle, ensures
maximum filtration time in subsequent cycles, which leads
to low impurities in the filtrate. This also cuts manpower
requirements by eliminating the need for frequent supervision.
Outotec Larox VPF filtration area is available upto 440m2
vessel dia 4,0 m (unit dry weight up to 34 tons)
Benefits

Safe operation and maintenance

High quality filtrate

Low operating costs and maintenance
costs

Low capital costs

Outotec Larox VPF filters are delivered as an automated
operational filtration system designed for sequence control
for multiple filters, which can be fully integrated with the plant
automation system.
Low capital costs
The filter geometry maximizes the filtration area vs. in
relation to the floor area. The Outotec Larox VPF ensures a
high filtration rate per filtration building floor area.
1. Filtration
During normal operation the slurry is fed into the filter vessel through the process inlet by a centrifugal pump. Outotec
Larox VPF filter is rated for process operating pressure of
450 kPa and feeding system is designed for careful flow and
pressure controlling throughout the filtration cycle. At first,
filtration is controlled by constant flow. When the internal
pressure increases due to cake resistance, filtration starts to
be controlled by constant pressure and the flow through the
filter starts to decrease.
2. Post filtration
When the flow arrives in pre-set limit of 1,0m³/m²/h, the
slurry feed stops. Compressed air pocket on the top of the
filter assists liquid level to drop and filtration to continue until
the level reaches the perforated section on the bottom of
elements.
1. Filtration
2. Post filtration
3. Residual slurry discharge
4. Cake sluice with wash spray
5. Refill the filter
6. Cloudy filtrate circulation
3. Residual slurry discharge
Residual slurry remaining in the bottom of the filter vessel is
directed to the feed slurry dump tank. Pressure in the vessel
is maintained with addition of process air from the top of the
vessel. Air pressure in the filter vessel holds the cake on the
elements.
4. Cake sluice with wash spray
Before the filter is drained totally empty the drain from to
filter is directed to the mud mix tank. The sluice wash spray
starts and the cake is sluiced down from the leaves. After that
the filter is allowed to drain empty.
5. Refill the filter
The new filtration cycle can be started by opening the feed
control valve and filter starts to be filled up. When the slurry
level reaches the top of the perforated section of the element
leaves, the filter will commence to pressurize and filtration
starts.
6. Cloudy filtrate circulation
In the beginning of the filtration cycle filtrate is dirty until some cake has been formed on the surface of the filter
media. Filtrate is initially circulated back to the cloudy filtrate
tank until desired filtrate clarity is achieved. Then the filter is
in the filtration cycle.
Slurry
Slurry
Solids
Solids
Vacuum
Air
ry
Solids
Filter cloth
Filter
cloth
Wash
Vacuum
Washliquid
liquid
r cloth
Filtrate
Wash
liquid
Filtrate
Air filtrate
Wash
Air
ate
Wash filtrate
Outotec Larox® DS
Pressure filters
Outotec Larox DS automatic pressure filters are
fully enclosed for the safe handling of hazardous
or corrosive processes that require containment.
The Outotec Larox DS series automatic pressure
filter (horizontal plate type) is a unique design with
double sided filtration in all chambers. Each chamber
has a diaphragm-type, filtrate collector plate on both
the top and bottom, covered with a section of the endless
filter cloth. This enables double-sided (DS) filtration as
the filter cake forms on both the upper and lower sides
of the chamber.
The Outotec Larox DS filter is totally enclosed and can
be operated either as a fume-tight or gas-tight filter.
Its custom-designed, all-polypropylene, diaphragm
filter plates provide maximum area for the filtration of
difficult materials in a contained environment.
Outotec Larox DS filtration area is available from 1.8 to
Extreme applications
The ultimate washing possibilities combined with
extremely dry filter cakes and contained processing,
have convinced many customers to select the Outotec
Larox DS filter for their process. The Outotec Larox
DS filter is ideally suited to sanitary, hazardous, toxic,
Benefits
solvent based or corrosive processes that require

Enclosed filtration
containment.

Superior performance

Single-sided cake discharge
filtering processes where more filtration area is

Easy operation
required and typically thinner filter cakes are formed.

Handles difficult materials
Outotec Larox DS is especially suitable for slower
Internal clean-inplace systems ensure total cleaning of
the filter as needed.
Outotec Larox® DM
Electrolyte filters for SX-EW
Outotec Larox DM electrolyte filters are specially
designed for excellent removal of entrained organic
and suspended solids from electrolyte, utilizing the
well proven dual media concept.
The Outotec Larox DM electrolyte filter is suitably
designed to be backwashed using either lean electrolyte
or water.
Adsorption filtration utilizing the well proven dual media
concept reduces entrained organic and particulate
concentrations to a level of a few parts per million.
Production capacities increase, as does the quality of
cathode products.
Low operating costs
Low electrical energy consumption is a cost-saving
Outotec Larox DM filtration area is available up to 275m2 /
benefit, as the adsorption filtration technique uses low
unit, vessel dia up to 5,2 m (Unit dry weight up to 13 tons)
pumping pressures compared to alternate solutions
utilizing flotation.
With no moving parts, the media cleaning system
ensures maximum media lifetimes. Typically the
Benefits
anthracite

Low operating costs

Automatic (PLC) control of the electrolyte filtration and

media
is
replaced
every
24
months
when combined with Outotec’s proven SX process
technology. Garnet lifetime is considerably longer.
media cleaning steps at the end of each filtration cycle
ensures maximum filtration time in subsequent cycles.
Outotec Larox DM electrolyte filters are delivered as an
automated operational filtration system which can be
fully integrated to any SX-EW solution package.
of SX production. Filter flow rates as high as 275 m 3 /
hr can be consistently handled by a single unit (5.2 m
Using lean electrolyte for backwashing and returning
diameter), greatly simplifying the process. Typically,
it to the After Settler after holding in a backwash
multiple units are installed in parallel for flexibility and
collection tank (see flow schematic) means Outotec
expandability to economically accommodate growing
Larox DM electrolyte filters do not reduce the capacity
plant capacity requirements.
Outotec Larox® Filtration Plants
Outotec Larox Filtration plants - Meet the toughest
industry standards and customer requirements
worldwide.
The Outotec Larox Filtration Plant is a standardized and
proven filtration plant concept that offers customers
a one-stop shop for sustainable plants. The modular
format enables the ideal configuration according to the
scope, scale-up and technological specification of each
plant. The compact and efficient design has various
sustainability features built in, such as water solutions
and dust control, to maximize recycling and provide a
Total Effluent Free (TEF) plant.
Outotec has a long track-record of determining filtration
process layout and sizing. From the vast equipment
and application portfolio and highly-refined base
documentation it is possible to generate the required
documentation for a standalone filtration plant cost- and
time-efficiently. Furthermore, there are no gray areas
as Outotec takes care of the all Front End Engineering
and Design (FEED) phases including all sub-systems
and support systems for the customer.
The tie-in points to the customer process are simple and
clear as the filtration plant is a standalone unit. The only
customer interfaces are slurry in, filtrate out, cake out
and utilities such as process water, power and plant
control system.
As the Outotec portfolio consists of standardized
Filtration Plant concepts, it is very straightforward to
configure the most feasible solution for the customer
Benefits
and generate the required documentation from the

One-stop shop

Technology fit and performance
shorter design phase execution

Minimized risks in project execution
reliability in content design

Standardized O&M procedures and
base material. Customer standardization means:
better response time
documentation
Pre delivery services
The Filtration plant projects starts with pre delivery

Predefined concept and modules enable
fast-track project execution and delivery
services, required phase of FEED and variety of
engineering scopes depending on customer needs

Compact and optimized realization
(Feasibility study, light basic engineering, basic

Guaranteed process performance
engineering and extended basic engineering).

Safety integral part of plant design

Life cycle services available
Good quality documentation is guaranteed in the FEED
phases and Outotec is committed to the results, giving
an accurate estimate in the final report.
Outotec Larox® Filtration Plant
Pre delivery services
•Feasibility study
•Light basic engineering
•Basic engineering
•Extended basic
engineering
Plant technical realization
•Outotec Larox PF plant
•Outotec Larox
FFP plant
•Outotec Larox CC plant
Delivery services
•EP engineering
•EPC engineering
•EPCM engineering
Life cycle services
•Spare parts
•Installation and start-up
•Maintenance
•Troubleshooting and
emergency
•Training
•Operate and maintain
The comprehensive testing capabilities and databases,
Proven application experience
combined with modular technology packages and
With the extensive application experience within the
higly refined base documentation speed the study and
industry, Outotec provides optimal solutions for clients
increase the reliability and flexibility.
filtration needs. From bulk mined products and metal
concentrates to metallurgy, Outotec’s experience (over
Outotec provides fully integrated technology solutions
70 large scale PF plants) ensures that every application
where all pieces fit seamlessly together, enabling
will perform to specification and operate to budget.
negotiations of the process guarantees, turn-key
deliveries and even “build and operate” service contract.
World-class product portfolio
With extensive range of filtration products, Outotec can
Plant technical realization
specify the optimum solution for virtually any mining or
Solutions based on the standard Outotec Filtration
metallurgical application.
Plant concept, enable the use of compact and flexible
project execution schedule.
Enhanced project execution allows several procurement
and construction activities to be run in parallel, which
speeds up the front end of the project as the selections
and approvals are done in the very beginning of
the project implementation, yet also enables agile
construction during later phases.
Delivery services
Outotec’s supply scope consists of detailed engineering,
supply of equipment and material in scope, automation
systems, erection, supervision, training of customers'
personnel and commissioning of the plant, which
guarantee performance for future success.
Life cycle service
Outotec provides services for the entire life cycle of the
filter plant through a global network of service centers
that are committed to providing support whenever
needed.
Plant technical realization is available for:
Outotec Larox PF Plant
Outotel Larox FFP Plant
Outotec Larox CC Plant
Sustainability
Sustainability is an important feature in all Outotec
Larox Filtration Plant deliveries, and the plant results
are based on optimized and high-value features:
Energy efficiency
Optimized equipment selection and material usage
Minimized water and air consumption
Water recycling
Possibility to process tailings, minimizing the
need for waste disposal and fresh water
Dust control and minimized emissions
Comprehensive testing
services and R&D
Outotec offers a versatile range of test filtration services. After each test the client receives a detailed report,
quantifying the technical and economic benefits of the Outotec solution.
Bench test filters
Test reports
Our bench test pressure and vacuum filters are used for
Outotec
preliminary screening and when only a limited amount of
filtrate samples using slurry obtained directly from
slurry is available. These test filters are also available to
the client’s process. Outotec test reports indicate the
clients who wish to perform regular tests on their slurry.
most appropriate filter type and potential process
testing
produces
dewatered
solids
and
improvements. Testing can be conducted at the Outotec
Laboratory filters
Research Center or at the client’s facilities. The Outotec
Research Center evaluates test results and advises test
Our laboratory pressure and vacuum filters simulate
engineers on the best methodology for each process.
the process at the client’s production site on a smaller
The Research Center continuously updates the testing
scale. All process and cost benefits of the application are
equipment to ensure accurate results. It also maintains
projected with reliable, repeatable test results that can
the Outotec Databank, a source of information on over
be used for filter sizing.
10 000 filtration tests.
Pilot filters
Continuous product development guarantees
Outotec test engineers work closely with the client’s
competitive solutions also for the future needs:
personnel to conduct test filtration for full-scale process

evaluations on site. Pilot units can be connected directly
and involvement in governmental
to the client’s filtration process. Outotec has a range
of pilot filters for pressure, polishing, capillary action
vacuum, and vacuum belt filtration to meet all possible
research projects

8 laboratories, 2 bench scale pilots and
1 industrial scale demo plant
process requirements. Pilot testing typically takes place
after laboratory scale testing.
Continuous cooperation with universities

Annual investments on R&D more than 20 M€
Stable process operation with
Outotec automation system
Our vast experience shows that a close link between process and automation design is vitally important to ensure
smooth process operation. With experience in designing fully automatic equipment for over 30 years, Outotec is
the undisputed leader in filtration automation. The Outotec solution today goes far beyond the simple automation
of functions.
Complete filtration plant control
The Outotec automation system automates, optimizes
and visualizes the entire filtration process, allowing
filtration plant operators to achieve better filtration
Benefits

Fully automated filter plant control

Electrical and instrumentation
engineering
performance and cost-efficient operations with minimal
intervention.
Outotec automation solutions include plant floor level

Process control and optimization

Real-time data acquisition, analysis and
visualization
automation for all filter types, as well as corporatewide visualization, real-time reporting and availability

web based reporting
analysis of the filtration plant. All Outotec automation
solutions are based on the same proven architecture
with modular functions customized to each installation.
The system provides plant operations, maintenance

Seamless integration with office software

Advanced real-time diagnostics

Remote access for comprehensive
support
and management with the data, condition monitoring
information, reporting and visualization needed to
keep both equipment availability and production costs
on target. Modem or web-based remote support from
Outotec’s experienced local or global service team helps
ensure continuous automated operation.
Control room, local area network, and

Continuous product improvement during
product life cycle
Outotec services improve
process performance
Outotec's comprehensive technology transfer package
Plant and process support services
can be completed with expert services and support.
Outotec customer service operates through a global
Outotec's advanced plant and process assessment,
network of local units that offers not only assistance
indentifies the areas for potential improvements,
meeting our customers' needs but also a commitment
e.g. equipment, automation systems, metallurgical
to providing advanced customer support whenever
processes and complete plants.
needed.
Outotec service experts provide punctual spare
parts logistics, maintenance and training, as well as
assessment and consulting services that generate a
competitive advantage for our customers.
What is more, we can make it much easier for our
customers to fulfill current and future legislation, by
ensuring that the plant and processes are running as
efficiently as possible, and that maintenance is being
carried out proactively.
We can tailor services efficiently to our customers'
specific needs, when considering the necessary
operational and maintenance services already from the
beginning of the project. As a trusted service partner,
Outotec ensures an optimized operation for the entire
lifetime of our customers' plants.
Equipment services
Benefits of Outotec services

Critical original spare parts in stock

Process and equipment know-how

Minimized downtime and unscheduled
Obtaining all spare parts and maintenance as well
as process and equipment design from the same
organization ensures that the plant runs optimally. We
make sure that our customers receive only the highest
quality parts, consumables and upgrades, that can be
seamlessly integrated into the plant.
stoppages

Maximum operating performance
Outotec filtration services
”Performance for life”
Outotec provides its customers with an comprehensive combination of process expertise and service. Outotec
delivers complete filtration solutions that exceed customer expectations in terms of product quality, safety, value
and consistency. All this in an energy-efficient and environmentally friendly way.
Outotec offers a comprehensive Performance for life
Outotec’s mission is to work together with its customers
service concept for its filtration solutions. Outotec’s
on a day-to-day basis to achieve their system and process
customer-centered
strategic
objectives for the entire lifetime of the solution. Outotec
life cycle planning already at the investment phase.
services
begin
with
supports its customers in achieving competitiveness
A nominated customer support engineer handles
by helping the customer in maximizing availability,
each project together with the project manager,
minimizing operating cost and optimizing process
providing a familiar and reliable point of contact for
results. The Performance for life service concept
the customer throughout the entire lifetime of the
developed by Outotec has proven to be an optimized,
filtration solution. Start-up and training services ensure
cost-effective and high-quality approach that meets the
optimal performance, while reliability is maintained
individual needs of the customer.
through spare part services, service agreements and
maintenance support. Filter performance can be further
enhanced through process optimization, modernization
and upgrades. Finally, Outotec offers refurbishment and
relocation/resale services that maximize the value of the
original filtration investment.
Outotec services offers:

Installation and start-up

Spare parts

Upgrades

Maintenance and technical services

Plant and equipment operations

Training
Libris, Finland, March 2012.
Outotec develops and provides technology solutions for the sustainable use of Earth’s natural
resources. As the global leader in minerals and metals processing technology, Outotec has developed
over decades several breakthrough technologies. The company also offers innovative solutions for
the chemical industry, industrial water treatment and the utilization of alternative energy sources.
Outotec shares are listed on the NASDAQ OMX Helsinki.
filtration@outotec.com
www.outotec.com
Copyright © 2012 Outotec Oyj. All rights reserved.