WORKING

In this type of filter system, the unfiltered liquid to be filtered enters the filter from the bottom under pressure into the centre channel and goes to the top of each plate fitted with filter media and spreads equally. The solid remain on the filter media and crystal clear filtrate flows out from openings on side of plates to the shell, which is led out through outlet pipe line. In this system, solids are evenly distributed on each plate which is easily retained inform of cake and it can be dried by applying maximum air or inert gas, steam at the end of cycle. Thus, this types of flow also ensure almost 100% filtration of the liquid.

DESCRIPTION

The operating principle of the filter unit is very simple. The liquid to be filtered is passed on the FILTER TANK by the TRANSFER PUMP. A CARTRIDGE PLATE ASSEMBLY. Consisting of several FILTER PLATE arranged with supporting SCREEN FILTER MEDIA and interlocking CUPS, is fitted in the filter tank. The liquid in the centre channel find its way to the center pressure cups through the circular openings on the side of the pressure cups. The filter media arrests foreign particle (solid particle) and allow the filtrate to pass through them and the screens and to run down the outlet pipe line.
This type of filter unit is primarily useful for obtaining filtrate, however in certain cases cakes can also be obtained in the space between the plates. All these are fully described below, however for the sake of convenience; the filter unit is completely arranged with Filter Plates, Supporting screen, Pressure cups, Filter paper etc. it should be normally for actual operation. The operator is therefore requested to study the assembly before dismantling, so that it will be easy for him to refit or actual operation.
After the last screen and paper are kept, put the Ring top and fasten the whole assembly with the 6 nos. tie rod Screw the bolts by hand and then uniformly by spanner. Keep the Neoprene Rubber Gasket in position between the bottom of the filter tank and the last plate. The cartridge assembly will fit in position, however care should be taken avoid leakage due to misfit ting. Once the cartridge is in position inside, insert the Center Tie Rod with Compressor Ring (Cup Type Washer). Tighten the Center Tie Rod Properly. Once more Tighten sides tie rods alternatively and uniformly. Close the filter tank by the Top Cover which also fitted with Air Vent on Top. This (Top cover) fits airtight on the Rubber Gasket fitted on the filter tank (Bottom cover) and it is then to be tightened by the tightening Bolts.

Operation For Filter Press

To start the actual operation after proper assembly, keep Air vent Valve on top of the Filter Tank, open in the initial stage to allow the inside air to escape. Keep the filtrate outlet valve. Partly open when the tank is full and the liquid begin to come out through the Air vent, close that valve similarly, when the job is completed, after stopping the transfer pump, the Air vent so that whatever Filtered Material is left in the Cartridge come out Slowly. If all the liquid is to be filtered a little air Pressure may be applied through the Air vent Valve on the Top. The Residual Unfiltered material may be taken out through the same Valve after taking out Cartridge Assembly.
On account of the suspensions collected on the filter media, the output will become lesser and lesser till a stage will come when the obstructing materials develop pressure inside tank. When pressure goes beyond 25 P.S.I and no appreciable filtration is obtained it is necessary to clean the filter assembly, in the meantime the bypass be conveniently operated to control the pressure?

SECTIONAL VIEW OF FILTER TANK WITH CARTRIDGE PLATE ASSEMBLY

Before every operation this assembly should be properly arranged as shown in the sketch. It will be advantageous to check the assembly before dismantling the unit when received. After opening the cover, unfasten the Center Tie Rod, which fixes the assembly in position. This Rod is supported on a compression cups, the whole cartridge assembly is to be taken out from the filter tank. There is hole of the Gasket inside with the hole in the bottom of filter tank it serves as a main Outlet. This gasket is an important sealing agent between the cartridge assembly and the filter tank. A set of plates is arranged and is held in position by means of Side Tie Rods. Unfasten the side tie rods and remove the Top Ring. Please note the position of the Filter Supporting Perforated Screen Interlocking Cups and Plates, One by one, noting their Respective Position. Remember the simple rule that all the supporting screen Except the Bottom Plate (Thick One) are inter Changeable.

THE FILTER PRESS CONSISTS OF THE FOLLOWING MAIN ASSEMBLIES

» Filter Tank with Cartridge main Assembly.
» Valve Assembly with Connecting Pipes.
» Transfer Pump with Electric Motor.
» All these are fully described below, however for the sake of convenience, the filter unit is completely arranged with Filter Plates, Supporting screen, Pressure cups, Filter paper etc. it should be normally for actual operation. The operator is therefore requested to study the assembly before dismantling, so that it will be easy for him to refit or actual operation.
» After the last screen and paper are kept, put the Ring top and fasten the whole assembly with the 4 nos. tie rod Screw the bolts by hand and then uniformly by spanner. Keep the Neoprene Rubber Gasket in position between the bottom of the filter tank and the last plate. The cartridge assembly will fit in position, however care should be taken avoid leakage due to mis fitting. Once the cartridge is in position inside, insert the Center Tie Rod with Compressor Ring (Cup Type Washer). Tighten the Center Tie Rod Properly. Once more Tighten sides tie rods alternatively and uniformly. Close the filter tank by the Top Cover which also fitted with Air Vent on Top. This (Top cover) fits airtight on the Rubber Gasket fitted on the filter tank(Bottom cover) and it is then to be tightened by the tightening Bolts.

THE FILTER PRESS CONSISTS OF THE FOLLOWING PARTS

Main Body : Material Of Construction for all Product contact parts is considered AISI 316 Quality. This is an austentic, which imparts hot strength characteristics. Material of Construction for Shell is considered as S.S. 316 quality of 3.15mm Thickness. It is the most widely used austenitic S.S. with excellent general corrosion resistance and forming characteristics.

CARTRIDGE FILTER ASSEMBLY CONSISTS OF FOLLOWING ITEMS

Plates : Material of Construction for Plate is considered as S.S. 316 quality of 16 swg. Thickness & Dia 8” – 14” – 18” – 24” – 33” with Height 38mm. Plate play a major role in filtration of liquid by holding Perforated sieves, Filter Media & foreign particles (in form of cake) up to specified capacity in a given area and allowing the liquid filtrate to pass.

Perforated Screen :
Material of Construction for Perforated screen is considered as S.S. 316 quality of 16 swg. Thickness with Dia 8” – 14” – 18” – 24” – 33” & screen hole Dia.3 mm. Perforated screen play a supporting role in filtration of liquid by supporting filter media in holding foreign particles in form of cake and allowing the liquid filtrate to pass.

Tie Rods :
Material of Construction for Tie rod is considered as S.S. 316 quality. Tie rod play a role of holding of cartridge filter assembly (in air tight fitting) in position.

Pressure Cups :
Material of Construction for Pressure cup is considered as S.S. 316 quality. Pressure cup play a role of holding of cartridge filter assembly (in air tight fitting) in central vertical channel formed & allowing unfiltered liquid to pass on filter media.

Scavenger Plate :
A filter, or plate (element) in the bottom of a cartridge filter assembly that recovers the liquid filtrate that remains in the filter tank at the end of a cycle. Material of Construction for Perforated screen is considered as S.S. 316 quality of 1.6 mm Thickness with Dia 8” – 14” – 18” – 24” – 33”.

Filter Media :
The surface upon which solids are retained or deposited in the process of filtration, is known as filter-medium.
The selection of filter-media depends on the optimization of following factors :-
» Should be chemically inert.
» Should have high retentive power.
» Should offer as little resistance as possible.
» Should be mechanically strong.
» Should absorb a negligible amount of dissolved material.
» Should be resistant to the corrosive action of the fluid.
» Should be cheap/economical.
» Should be easy to handle and resistance to heat.
» Should be easily available and re-usable.

Note :
Large number of materials depending upon the merits or characteristics are used for this purpose in pharmaceutical industries. At times the properties of liquids under filtration also decide the choice of filter-medium.
(In short, recommendation of the media depends on the chemistry of the products and pressure drop etc.)

Vent :
» An opening through which air can leave an enclosed chamber.
» Material of Construction for Vent is considered as S.S. 316 quality.

Glycerin / Liquid Filled Pressure Gauges :
Glycerin filled pressure Gauges, designed for tough application. These pressure gauges provide an extra margin of protection from vibration and erratic pulsation. . It is filled with Glycerin in stainless steel casing. Accuracy 1.5% or + 2%. They are installed on power pack, hydraulic machinery, pumps, compressors, power plants, pipelines and transmission stations where vibration and pulsation are destructive factors.

Ball Valves :
Material of Construction for Ball valves is considered as S.S. 316 quality. Ball valves use a ball to block the flow of fluid through the valve. The ball has a cylindrical hole through it. When the hole is in the pipe, flow is permitted. When the ball is turned 90 degrees, its solid surface blocks the fluid flow. The ball and the facing pieces of the body of the valve are carefully machined to provide a good metal-to-metal seal. However, the ball is primarily sealed by two heavy seat rings that press tightly on the ball from opposite sides. It is as though a golf ball were sandwiched between two doughnuts. Assuming perfect circles there would be a perfect contact and seal between each doughnut and the surface of the ball.
When the valve is closed, pressure in the line helps to keep it closed, which is one advantage of this type of valve. Another advantage is that fluid can flow through it in either direction, as desired.

Centrifugal Pump :
Material of Construction for Centrifugal Pump is considered as S.S. 316 quality. Centrifugal pump receives energy form its prime mover (i.e. electric motor) and imparts it to the liquid being pumped by centrifugal force. This function is performed by impeller coupled to the prime mover. The liquid is forced into impeller either by atmospheric pressure (or by virtue of its being at higher level). When this liquid enters the vanes of rotating impeller it gets rotated centrifugally by the impeller which imparts kinetic energy of prime mover to the liquid. Thus the liquid leaves the impeller at a high velocity. This velocity energy is then converted into pressure energy by means of a volute casing (or by a stationery diffuser ring in case of turbine pump) surrounding the impeller periphery. The velocity energy gets converted into pressure energy due to gradually enlarging area of volute casing (or diffuser vanes).

Three Phase Motor :
Three phase motor is that motor which is operated by three phase supply. Its main parts is
a) Stator
b) Rotor
Three sets of winding are mounted on the stator of three phase induction motor. When three phase A.C. current is applied to these sets of winding, a magnetic field is generated in each set of winding, which when combined produces a rotating magnetic fields.

Trolley :
Material of Construction for Trolley is considered as S.S. 304 quality made out of 10 Swg thick sheet fitted handle and 4 nos. of PU castor Wheels (having two fix-type and two revolving type), with S.S. 304 quality bracket.

Gasket :
It is a packing used for making the leak proof joint between the two flat surface of filter press.