1. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
1
Dewatering Fine Coal Tailings with
Recessed Chamber or Membrane
Plate Filter Presses
P. Godwin2 , C. Jenson1 and T. Park1 1
McLanahan Corporation
2 McLanahan Corporation Pty Ltd
ABSTRACT
Many coal mines have recently turned to the use of recessed chamber or membrane plate filter
presses for dewatering fine coal tailings. This change is being brought about due to increasing
environmental constraints and cost savings versus alternative technologies (eg tailings dams,
belt presses, centrifuges). This paper gives an overview of how filter presses work and the typical
styles and options available. It concludes with several case studies of filter presses dewatering
fine coal tailings.
RECESSED CHAMBER AND MEMBRANE PLATE FILTER PRESSES
FILTER PRESSES OF TODAY VERSUS PLATE AND FRAME PRESSES OF THE PAST
Typical Process Description
The underflow from a thickener is pumped to a stirred holding tank,‘surge tank’, rather than a
tailings pond. The tank discharges via a high pressure slurry pump, feeding the filter press,‘feed
pump’. The filter press operates in batch cycles, controlled by a Programmable Logic Controller
(PLC). The cycle starts by the press closing and locking. The feed pump then fills the chambers
inside the press and begins dewatering the slurry using the fluid pressure generated from the
feed pump. The press retains the solids, but passes the water (filtrate) through the filter media
and away.
‘Recessed Plate’ – When the desired cake moisture is achieved, based on filtrate flow, the feed
pump stops. The press is then unlocked, and the filter plates open discharging dewatered cakes.
‘Membrane Plate’ – When the desired amount of feed solids has been pumped into the
recessed membrane plates, the feed pump stops. Water is pumped behind the membranes
squeezing the individual filter cakes. Once the desired squeeze time has been reached the
membrane water is discharged to depressurize the membranes, the press is then unlocked, and
the filter plates open discharging the dewatered cakes.
The filter cakes are typically discharged onto a conveyor or directly onto the ground. Then the
cycle repeats. A typical flow diagram is given in Figure 1.

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Figure 1 Typical Flow Sheet for a Filter Press with Core Blow and Dual Feed Inlets
General Composition of Filter Presses
Filter presses are composed of filter plates which are held together during dewatering. The size
of the press is determined by the number, size and depth of the filter plates. When these plates
are closed together they create cavities which can be pumped full of solids for dewatering. The
plates are covered with a filter media that traps the solids inside the cavities formed between
the plates and allows the water (filtrate) to pass through the cloth and be recycled. Filter plates
can be divided into three general styles (see Figure 2):
• plate and frame style;
• recessed chamber style; and
• membrane plate style
Filter presses using the three styles of plates noted above are in wide use today in many
dewatering applications in a wide range of industries.
Figure 2 Different Plate Styles

3. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
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Plate and Frame Style Filter Plates
‘Plate and frame’style plates are one of the oldest styles available and are frequently confused
with newer styles. In order to form a chamber on a‘plate and frame’filter press two flat plates
where closed against a frame to form each chamber. The total number of frames would result in
the number of cakes to be discharged each cycle with each frame being enclosed between two
plates. The frame thickness between the flat plates would create the depth of the chamber and
resulting cake thickness which would form inside of this frame. With the formation of the filter
cake inside the frame there were many issues with removal of the cakes once the flat plates
where pulled apart from the frame encasing the filter cake. Operator intervention was often
required to help knock the cakes out of the frames of the plate and frame style plates.
Although these issues have been resolved with the newer plate styles which will be discussed
below many people still unknowingly call all styles of filter presses‘plate and frame’presses
even if the filter press uses newer style‘recessed chamber’or‘membrane’style filter plates.
This is probably brought about by a misconception of thinking the frame used in‘plate and
frame’refers to the frame of the machine when it actually refers to the style of filter plates
being used on the filter press.
Recessed Chamber Filter Plates
‘Recessed chamber’style plates were created to overcome the problems associated with cake
release in older plate and frame style plates. The plates in recessed chamber filter presses are
recessed on each side, hence the name‘recessed chamber’Filter Plates. As a result when two
‘recessed chamber’filter plates are closed next to each other a cavity is formed between the two
plates resulting in the‘chamber depth’or‘cake thickness’. The cake thickness with recessed
chamber plates is then equal to the summation of two adjoining plates (eg 20 mm recess on the
right side of Plate #1 plus 20 mm recess on left side of plate #2 = 40 mm cake thickness when
the two plates are closed against each other). The first and last plates in a plate pack are only
recessed on one side so that a partial cake does not form between the end plates and the frame
of the filter press itself. As a result a‘recessed chamber’filter press with 150 plates would form
149 filter cakes.
Dewatering with a recessed chamber filter press is similar to dewatering with plate and frame
style plates. The slurry to be dewatered is pumped into the empty chambers formed between
the closed plates and the pressure created from the slurry forces more solids into the press
until the chambers are packed full of solids. Various methods such as time, back pressure, feed
or filtrate flow rates can determine when the cakes are fully formed. Once the cakes are formed
the feed pump is shut off and the filter plates are pulled apart using various opening
mechanisms. Once the plates are pulled apart the filter cakes are able to easily fall out from
between the plates as they are not encased in a frame as they were with the older style‘plate
and frame’plates.
A common misconception with‘plate and frame’and‘recessed chamber’filter plates is that the
filter press squeezes the cakes to dewater the slurry. In actuality the plates are held closed,
typically with hydraulic ram(s) sufficient to overcome the force created by the slurry, and the
dewatering is done using the fluid pressure created from the feed pump. The opening and
closing of the filter press is only required to separate the plates and allow the cakes to discharge
at the end of each cycle.

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Membrane Filter Plates
‘Membrane’filter plates are a variation on‘recessed chamber’filter plates. The membrane filter
plates are recessed on each side of the plate like recessed chamber plates but also have a
diaphragm or membrane which lines each side of the membrane filter plate. The membrane is
used at the end of each cycle to physically squeeze each cake after the cavities formed between
the plates have been filled with solids. The cavities formed between the plates are filled with
solids by pumping slurry into the plates generally with pressures of no more than 690 kPa. Then
the membranes are pressurized using water or air behind the membranes to push the
membrane into the cavity and physically squeeze each individual cake. It is generally
recommended to use water for squeeze pressures over 860 kPa for safety reasons due to the
compressive and explosive nature of compressed air.
The more compressible the solids are that are being dewatered the more benefit can be
attained by using membrane style filter plates. An analogy would be that if you squeeze a slurry
full of ball bearings in membrane filter plates you may only be able to rearrange the ball
bearings a little better resulting in a slightly drier cake. If however the solids being dewatered
are compressible like a sponge then a significant difference can be attained. Due to the flexing
of the membranes each cycle, membrane plates will eventually fail and need to be replaced due
to fatigue from flexing. As a result, the costs/benefits of membrane style plates have to be
weighed against the dewatering requirements to meet the needs of the end use of the filter
cakes (eg compaction in an impoundment, hauling costs, etc.).
In tests performed by McLanahan, dewatering fine coal tailings, similar capacities for a given
machine length have been seen using‘recessed chamber’or‘membrane’style plates. The
percent solids by weight of the filter cakes using‘recessed chamber’plates is typically between
70 – 80% solids w/w with the percent solids by weight of the filter cakes from‘membrane’style
plates typically being a 73 – 83% solids w/w or a few points higher. However in some cases air
can be blown through the filter cakes‘cake blow’on more permeable filter cakes which in some
cases results in similar percent solids using either style of filter plate.
Membrane plates are supplied in two main plate configurations:
• All plates on the filter press being composed of‘membrane’plates; and
• Every other plate being a‘membrane’plate and the alternate plates being composed of
‘companion plates’which are essentially the same as‘recessed chamber’plates. This
configuration is called a‘mixed pack membrane’filter press and is the more frequently
supplied configuration for these types of applications as it results in less‘membrane’plates
and consequently lowers upfront capital costs and lower long-term operating costs.
Membrane plates are available in two main styles:
• Welded membranes – The membranes are heat welded to the body of the plate. When the
membrane fails from flex fatigue the entire plate has to be replaced; and
• Replaceable membranes – The membranes are replaceable and attach to the plates in various
methods depending on the filter plate manufacturer. This allows the membranes to be
replaced when they fail without replacing the entire plate.
Filter Press Sizes
Filter plates generally come in dimensions from 400 x 400 mm to 2000 x 2500 mm with chamber
thickness ranging from 15 to 50 mm. For plate and frame and recessed chamber plates the
‘chamber thickness’is equal to the final‘Cake Thickness’as the cakes are not squeezed during

5. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
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the dewatering. The plates are most commonly made of polypropylene and manufactured
through compression molding. The number of filter plates on a filter press can range from as
little as 3 or 4 plates to more than 180 filter plates on a single press. The frames which support
the weight of the plates and cakes are generally broken down into two categories denoted as
Overhead Beam or Side Beam filter presses which will be discussed in more detail later. The
number, size and chamber depth of the plates determines the filter press size.
Cake Thickness
Besides plate size, plate style and number of plates, another key component in dimensioning
the filter press is to determine the proper chamber thickness or cake thickness. With chamber
thicknesses available from 15 to 50 mm it is important to evaluate the dewatering rates using
various thicknesses. For very permeable materials the layer of solids building up on the filter
media does not have a great impact on the dewatering rates and thicker chamber thicknesses
can be used.
In tailing applications where permeability of the cake forming on the filter media often
decreases significantly as the cake builds up, using a chamber that is 10 or 15 mm thicker can
often result in cycles that are up to 2 – 3 times longer resulting in much greater fluctuations in
cycle times throughout the day. As a result thinner‘recessed chamber’cakes (25 mm versus
40 mm) or‘membrane’plates (40 mm which will then be compressed) are generally preferable
in tailings applications. Tests can be performed to evaluate changes in permeability with
varying cake thicknesses and a conservative approach leads to selection of thinner recessed
chamber plates or membrane plates to reduce impacts of feed changes on cycle times and
dewatering performance.
Filter Press Capacity
Once the total volume of the filter press is determined, Mass Balance calculations are used to
determine the weight of solids that will be discharged per cycle and the number of cycles that
will be discharged per hour. Capacity of a filter press/hr is then calculated as:
• Volume discharged per cycle = Volume of each chamber × Total number of Chambers;
• Weight of solids discharged per cycle = Volume discharged per cycle × relative density of the
filter cake × Percent solids of the filter cake;
• Cycles per hour = Cycle time in minutes/60 minutes; and
• Capacity per hour = Weight of solids discharged per cycle × Number of cycles per hour.
Cycle Time
The cycle time is typically broken down into the following components:
• Closing time – Time it takes for the filter press to close and build sufficient pressure to hold
the plates closed during dewatering;
• Fill time – Time it takes to fill the empty volume of the press with slurry;
• Ramp time – Time to build pressure during filtration to the terminal or final pressure;
• Filtration time – Time the pump continues to pump at the terminal pressure;
• Cake Blow time (w/Cake Blow option) – Time air is blown through the filter cakes;
• Core Wash/Core Blow time (w/Core Wash/Core Blow option) – Time for water and air to flush
out the feed core of slurry; and

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• Opening time – Time to open the mobile plate and all the filter plates to discharge the cakes
and be ready to start another cycle.
Note: It is important to allow for extra time (Safety Factor) to stages of the process that can be
variable. For example in a tailings application the filtration time is impacted by the underflow
density, feed gradation, clay content and chemical dosing in the thickener. A safety factor can
be added to this time to allow for these variations. For more consistent feeds such as dewatering
metal concentrates less safety factor is needed.
Filter Media
The selection of proper filter media is critical for optimal cake release as well as achieving the
desired filtrate clarity and wear life. The main criteria used in determining the correct filter cloth
for an application are:
• air permeability;
• weave;
• type of fibres used (most commonly Nylon, Polypropylene of varying types) and their
electrical affinity or chemical degradation with respect to the material being dewatered;
• thickness or diameter of each fibre;
• are the fibres‘Mono-filament’or essentially single strands like a fishing line which are better
for cake release or are they‘Multi-filament’like a rope composed of twisted strands which can
be better for particle capture;
• density per unit of area of the cloth. Higher densities are more durable to support release of
higher density filter cakes to prevent‘Blousing’or stretching of the filter cloth; and
• coefficient of Friction.
Side Beam Filter Presses
‘Side Beam’style filter presses use beams running along the sides of the filter press to support
the weight of the filter plates and filter cake as well as the dynamic loads created by the closing
forces of the filter press. Advantages typically noted for this style of filter press are:
• fast opening system;
• easier to implement plate shaking systems;
• allows for faster low pressure wash systems used commonly in mineral concentrate
applications; and
• shorter height for small portable applications.

7. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
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Figure 3 McLanahan Side Beam Filter Press
Overhead Beam Filter Presses
‘Overhead beam’style filter presses use beams located above the plates to support the weight
of the plates. Advantages typically noted for this style of filter press are:
• Suspension of the plates from overhead beams allows the dynamic loads/forces created from
the hydraulic ram(s) holding the filter plates closed to be isolated or reduced from loading
the beams which support the weight of the filter plates. These forces can be as high as 6670
kN of force on a 2000 mm x 2000 mm press operating at a feed pressure of 1550 kPa.
• Easier access for cleaning and change out of the filter cloths as there are no beams in the way
on the side of the filter press
• Wider opening between the filter plates (up to approximately 900 mm) resulting in:
º Less abrasion as cakes are released;
º More movement to help cake release;
º Plates are too far apart for the filter cakes to be attached to the cloths on both plates
resulting in half the surface tension and improved cake release;
º Fast plate opening to keep cycle times down; and
• Simple and fast opening with limited moving parts.
• More suitable for high-pressure cloth washing systems due to increased space between the
plates. High-pressure wash can be done with an operator or automated system.

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Figure 4 McLanahan Overhead Beam Filter Press
FILTER PRESS OPTIONS
Filtrate Discharge Options
The filtrate can typically be discharged from the filter plates in two commonly used methods:
• Internal – The filtrate passes through a manifold created by the holes located in the corners of
the filter plates. This is a lower cost option and is desirable when the filtrate contains
chemicals that should not be exposed to the air; and
• Open Filtrate Discharge – The filtrate exits each plate through individual spigots found on
each plate. This option is preferable to allow easy identification of damaged filter cloths for
the operator. Quick identification of damaged filter cloths prevents unnecessary abrasion to
the filter plates.
Figure 5 Open Filtrate Discharge

9. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
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Dual Feed Inlets
Dual feed inlets reduce the inlet velocity in half. This option helps reduce wear on filter cloths
and also ensure a more even distribution of the feed pressure for dewatering in large filter
presses. Having dual feed inlets also allows for easy addition of‘Core Wash/Core Blow’options
which require dual feed inlets.
Core Wash/Core Blow
When it is desirable to eliminate the discharge of the feed core which is not dewatered during
normal filtration‘Core Wash’and/or‘Core Blow’options are used.
• Core Wash –‘Core wash’uses a pressurized water line to wash out the feed core prior to
opening of the filter press. This prevents buildup of slurry on the plates which can reduce
cloth washing and blowouts (leaks between the filter plates); and
• Core Blow –‘Core blow’uses pressurised air to evacuate the slurry from the feed core. This
prevents buildup of slurry on the plates which can reduce cloth washing and blowouts. If a
‘core wash’is used prior to the‘core blow’then the pressurized air only needs to remove the
water from the feed core. This combination of using a‘core wash’followed by a‘core blow’is
the most efficient option.
CAKE BLOW
On materials that can be dewatered quickly due to their high permeability it is possible to blow
air through the filter cakes at the end of the cycle in order to remove additional amounts of
moisture from the filter cake. In some coal tailings applications with limited amounts of clay this
can be as much as 5 additional points (eg 80% vs 75% solids w/w.)
Automatic Filter Cloth Wash
Most tailings applications only require filter cloth washing once every week to two weeks. When
desired to reduce operator requirements it is possible to automate this function.
Drip-Tray or Bomb Bay Doors
When an automated cloth wash is used it is typically necessary to use a drip-tray or bomb bay
doors underneath the filter press to capture the water coming from the cloth wash and prevent
it from going onto the filter cakes.
FILTER PRESS ANCILLARIES
Feed Pump
The feed pump is a slurry pump or series of slurry pumps designed to generate the necessary
flows and pressures required during the cycle. Depending on the flows and pressures required
typically centrifugal, double diaphragm or piston diaphragm pumps are used.
Surge Tank
The surge tank receives the thickened slurry and buffers the flow between the thickener
(continuous process) and the filter press(es) (batch process). Proper selection of the surge tank
ensures a smooth transition from the continuous process coming from the wash plant to the
batch process of the filter press. Surge tank(s) are typically sized to store 1.5 filter press cycles or
more of slurry. The filter press is typically automated to wait until there is enough slurry in the
surge tank for a complete cycle before starting a cycle.

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TESTING FOR SIZING AND SELECTION PURPOSES
Lab Tests
Common tests performed on Coal Tailings for selection of a filter press for Coal Tailings
applications include:
• Filtration tests. Tests are performed at varying feed solids, cake thickness, and pressures to
determine filtration times and percent solids achievable;
• size distribution;
• % solids; and
• Relative density (RD). It is important to accurately determine two components of the RD for
accurate sizing:
º RD of the slurry – the feed density has a large impact on the cycle times; and
º RD of the solids – to accurately determine the weight of solids discharged from the filter
press each cycle at a given cake moisture the relative density of the solids is required.
Pilot Testing
For sites with existing Coal Prep Plants it is possible to bring demonstration equipment on site
to perform on site filtration tests.
CASE STUDY 1
Dewatering Fine Coal Tailings in Bishop, WV with two McLanahan ‘Recessed
Chamber’ filter presses
BACKGROUND
McLanahan was approached by Taggart in 2011 (now DRA Global) about a project where Justice
Corporation needed to dewater their fine coal tailings at a greenfield site in Bishop, WV without
the use of settling ponds. Forge (ie Taggart) supplied slurry samples and design criteria to
McLanahan for machine selection to meet these requirements. The McLanahan recessed
chamber filter presses were purchased by DRA Global and commissioned in February of 2013
and have been operating since that time without the use of settling ponds.
Design Criteria
Material: Thickener Underflow (Coal) Solids Flow Rate: 68 dry t/h
RD of Solids: 1.6
Thickener Underflow Density: 30% Solids by weight
Objective: Dewater thickener underflow into a ~75% solids w/w cake
Lab Testing
Lab tests were performed to evaluate filtration times and cake moistures achievable on the
thickener underflow sample submitted from Forge Group.

11. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
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Figure 6 Dewatered Filter Cakes from 5 and 10 Minute Filtration Tests on Submitted Samples
Equipment Selected
2 x filter presses 2 x 2 m with 155 – 25 mm recessed chamber plates
2 x feed pumps 130 kW 10 x 8 double stage feed pumps
Discharge volume/press: 13.1 m3/cycle
Dry solids discharged/cycle/press: 13.6 tonnes
To achieve the 68 t/h required each press needed to achieve 2.5 cycles per hour or 24 minute
cycles. 2 Presses x 2.5 Cycles/Hour/Press x 13.6 tonnes/Cycle = 68 t/h
Figure 7 McLanahan Overhead Beam Filter Presses at Justice Coal Prep Plant in Bishop, WV

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Installation
Installation was done by DRA Global with assembly supervision of the filter presses from
McLanahan Field Service personnel. DRA Global provided the turnkey installation of the entire
coal prep plant.
Commissioning
Commissioning was done with personnel from McLanahan Corporation and DRA Global from
February 22 to February 28, 2013.
Performance
The filter cakes have consistently exceeded the 75% solids w/w required and have been tested
to be typically around 79 – 80% w/w solids with cycle times within the expected range based on
the initial lab testing.
Complete cycles have been able to run as short as 15 minutes per cycle resulting in up to
108 dry t/h with both presses running. The installation of the McLanahan filter presses has
allowed Justice Corporation to meet their goals of running without any settling ponds while
keeping up with the tailings generated from the Coal Prep Plant.
Filter Cloths – To date approximately 6 of the 310 filter cloths have been replaced far exceeding
the estimated wear life of 3000 – 6000 hours.
Figure 8 Dewatered Filter Cake at 79% Solids w/w and Recycled Water (Filtrate) from the McLanahan Presses at
Justice Corporation in Bishop, WV
CASE STUDY 2
Dewatering of Coal Tailings at a coal mine located in Indiana USA, using 2 x
McLanahan Recessed Chamber filter presses and 2 x McLanahan Membrane Plate
filter presses
BACKGROUND
The existing tailings dam(s) were approaching capacity and the decision was made to convert
wet tailings to dry cake for disposal with coarse rejects. The equipment selection would need to
produce a dry enough cake to meet compaction requirements and thereby eliminate the need
for future tailings dams.

13. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
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After testing and working with multiple vendors the customer decided that using either
recessed or membrane plate filter presses were the best option in order to meet their
compaction requirements. Pilot testing was performed on site by McLanahan to generate
enough filter cake to ensure the moisture levels reached would perform adequately to meet
their compaction requirements for their reclamation plan.
Design Criteria
Material: Thickener Underflow (Coal) Solids Flow Rate; 195 t/h
RD of Solids: 1.7
RD of Slurry: 1.2 to 1.35
Ash Content: 24.5 – 39.4%
Sulfur Content: 2.5 – 5.3%
Thickener Underflow Density: 44% solids by weight
Objective: Dewater thickener underflow into a ~75% solids w/w cake
Lab Testing
Lab tests were performed to evaluate filtration times and cake moistures achievable on the
thickener underflow sample submitted Lab testing indicated:
Pressure 15 Bar with 4 min filtration times would achieve an average of 74% solids w/w.
By adding 3 min of cake blow, cake solids were calculated to increase to an average of 76.5%
solids w/w.
Equipment Selected
2 x 180 Plate 2 x 2 m x 25 mm Recessed Chamber
2 x 151 Plate 2 x 2 m x 40 mm Membrane Plate
Note that all filter 4 filter presses, shared a common size filter press frame, and all fed from a
common single agitated surge tank.
Because the membrane plate presses were able to achieve slightly lower moisture contents in
testing (2 – 3 % points drier) it was decided by the customer to install 2 recessed chamber
presses which have lower operating costs and 2 membrane plate presses which achieved
slightly lower moisture cakes. This would allow the customer to blend the cakes as needed to
achieve the compaction requirements.

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Figure 9 McLanahan Overhead Beam Filter Presses installed in Indiana
Installation
Graber Construction did the installation of the equipment with supervision from McLanahan
Field Service.
Commissioning
Commissioning was done by McLanahan with assistance of Graber and onsite personnel.
Performance
The 2 x 180 Plate 2 m x 2 m x 25 mm recessed chamber filter presses operate with total cycle
times of 20 – 24 min, at 15 Bar pressure, with the cycle including the 3 min of cake blow. The
resulting filter cake has an average cake solids of 77 – 78% w/w.
The 2 x 151 Plate 2 m x 2 m x 40 mm membrane plate filter presses operate with a feeding
pressure of 8 Bar and squeeze pressure of 15 Bar with a total cycle times 20 – 24 min including
3 min of cake blow. The resulting filter cake has an average cake solids of 78 – 79% solids w/w.

15. Dewatering Fine Coal Tailings with Recessed Chamber or Membrane Plate Filter Presses
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Table 1 Comparison of Filter Presses installed in CoalTailings Applications
Year Location Customer Qty
Size and
Model
Plate Type
Feed %
Solids w/w
Cycle
Time
Cake
Moisture
TPH
2009 IN/USA
1st Site in
Indiana
1
1.5 m x 1.5
m x 100 x
35 mm
Recessed 25 – 35%
15
– 20
min
22 – 25% 22+
2011 WV/USA
Taggart/
Bishop
2
2 m x 2 m
x 155 x 25
mm
Recessed 30%
15
– 22
min
20% 72+
2012 Russia
Severstal
Resources
2
2 m x 2 m
x 170 x 25
mm
Recessed 25 – 40%
20
min
17 – 20% 90+
2013 IN/USA
2nd Site
in Indiana
2
2 m x 2 m
x 180 x 25
mm
Recessed 44%
20
– 24
min
22%
195+
2
2 m x 2 m
x 151 x 40
mm
Membrane 44%
23
– 27
min
21%
CONCLUSION
Recessed chamber and membrane plate overhead beam filter presses are currently in use in the
US and elsewhere in the world to effectively and economically dewater coal tailings.
Filter presses should be a considered option wherever the site requirements call for lower
moisture, higher recovery of water, or dry stacking as an alternative to traditional tailings dams.
ACKNOWLEDGEMENTS
Thanks are extended to Justice Corporation and DRA Global (formerly Taggart) who were
involved in the selection and operation of the McLanahan filter presses in the Case Study.
REFERENCES
Jenson, C., 2014, “Dewatering Coal Tailings”, 2014 Coal Prep Conference Proceedings.
Jenson, C., 2012, “A Pressing Need”, World Coal, V21, N12, pp28–34.
Jenson, C., 2014, “Dewatering Fines”, Coal Age, March, pp38–40.