Membrane Filter Presses Podcast Edit Discuss 1 Upload Video
A diaphragm filter press, also known as a diaphragm filter press, is a filter press with an elastic membrane added between the filter plate and the filter cloth. In the process of use, when the feeding is over, a high pressure fluid or gas medium can be injected into the diaphragm plate, when the whole diaphragm will bulge and press the filter cake, thus achieving further dewatering of the filter cake, which is commonly referred to as press filtration.
Chinese name diaphragm filter press Alias diaphragm filter press Type of filter plate and filter cloth Property of filter press
Catalogue
1 Overview
2 Classification of diaphragms
3 Installation precautions
4 Precautions for use
5 Principle of Operation
Overview Editorial Podcast
Manual diaphragm filter presses
Manual diaphragm filter press
The diaphragm filter press has the advantages of high pressing pressure, good corrosion resistance easy maintenance, safety and reliability, etc. It is the first choice for customers in metallurgy, gas, paper making, coking, pharmaceutical, food, brewing and fine chemical industries.
Diaphragm filter presses have been widely used in various fields that require solid-liquid separation. The diaphragm filter press is considered to be an alternative and upgraded equipment to the common chamber filter press.
The diaphragm filter press has shown good results in terms of capacity per unit area, reduction of cake moisture, and adaptability to the nature of the material to be treated.
Diaphragm filter press picture
Diaphragm filter press picture (3 pictures)
The main difference between the diaphragm filter press and the ordinary chamber filter press is the addition of two elastic membranes on both sides of the filter plate (the compound rubber diaphragm is the overall diaphragm). During operation, when the feeding is over, the high-pressure fluid medium can be injected into the diaphragm plate, at which time the whole diaphragm will bulge and press the filter cake, thus achieving further dewatering of the cake, which is press filtration.
The membrane filter press is used in sludge and sewage treatment, the minimum water content of the filter cake has been achieved below 60%, compared with the traditional chamber filter press, the highest solids content of the filter cake can be increased by more than 2 times, the transport cost of the filter cake is greatly reduced, the filter cake can enter the power plant direct combustion, the real sludge into resources, sewage into a clear spring, completely replaced the chamber filter press
Diaphragm classification editorial Podcast
For different diaphragm materials, the new generation of diaphragm filter presses can be divided into rubber diaphragm type and polymer elastomer diaphragm type diaphragm filter presses.
Fully automatic diaphragm filter presses – reinforced polypropylene type
Fully automatic diaphragm filter presses – reinforced polypropylene type
The rubber diaphragm filter press is ideal for filtering materials with weak acids, weak bases and non-organic solvents. The rubber diaphragm filter press changes the shortcomings of the past split fixed type to save energy consumption after feeding. The new design makes the rubber diaphragm drum more adequate and uses less pressure and air volume, and in the case of the same air source air volume, the rubber diaphragm drum is three times as large as the polymer diaphragm drum, which can greatly reduce energy consumption.
The polymer elastomer diaphragm filter press is then used for strong acid, strong alkali and organic solvent materials, with relatively more ideal performance and longer service life. The presses are available as gas (air) presses and liquid (water) presses to meet the needs of different industries. Depending on the customer’s needs the press components can be configured as food grade or general grade and the control can be PLC and human-machine interface. For general materials, the diaphragm drum can be fully pressed and dewatered after 3-15 minutes. For some special materials a segmented pressing method of low pressure pressing followed by high pressure pressing can also be used.
The membrane filter press achieves an efficient dewatering filtration process and guarantees the best filtration effect of the filter press, significantly reducing the water content of the filter cake. At the end of the feeding process, the filter cake is pressed to increase the dewatering efficiency of the machine, increase the dryness of the filter cake, reduce contamination and reduce labour, even eliminating the drying process in some processes.
Installation Notes Editorial Podcast
1、First of all, the foundation of the diaphragm filter press should be leveled before installation, and the horizontal error of each installation datum should not exceed 2mm.
2、Installation of cylinder support, leveling with pad plate, the upper plane of the two supports on the same level, the bolts between the cylinder and the support are not tightened, then the cylinder is installed on the cylinder support, and the ground bolts are tightened.
3、Install the tail plate. Lift the tail plate (use wire rope to lift the centre hole of the tail plate) to connect the tail plate with the main beam.
4、Install the main beam pillar. Assemble a main beam with the oil cylinder and fix the main beam with the middle pillar using the main beam clamp.
5、Flatten the installed tail plate, install another main beam and fix it with a cleat, the two main beams and tail plate positioning jaws should be installed in place, leaving no gap.
6、Septum leveling. Use level to measure the level of the two main beams, the height difference between any two points on the two main beams should be less than 3mm, the height of the main beam is adjusted by the main beam pillar, the error of the two diagonals of the frame should be less than 6mm, which can be reached by adjusting the left and right position of the tail plate.
7、Install the head plate. Hang the head plate on the two main beam tracks, check the coaxiality of the spherical end cap and the piston rod, the coaxiality tolerance is 2mm, the coaxiality can be achieved by moving the spherical end cap up and down and left and right, install the pressure plate to connect the head plate with the piston rod.
8、Install the rail box bracket and the upper and lower rail box.
9、Install the transmission part. Including sprockets, chains, oil motors, hook boxes, etc. When connecting the chain and pull hook box, make the two pull hook boxes close to the positioning plate at the end of the rail box, and ensure that the synchronization accuracy of the two pull hook boxes is less than 4mm.
10、Lift the filter plate to the main beam track, positioning the handle on the same side.
11、Install the filter cloth, put on the filter cloth pressure ring (sewn filter cloth without pressure ring).
12、Adjust the height of the track box, the distance between the bottom of the filter board handle and the bottom of the upper track box is, in order to achieve stable and reliable work of the pulling board.
Use precautions edit broadcast
1、Operators must be familiar with the content of the instruction manual and operate, adjust, use and maintain strictly according to the requirements of the manual.
2、Choose high quality filter cloth, the filter cloth should not be broken, the sealing surface is not wrinkled and not overlapped.
3、Frequently check whether the machine parts and components are installed safely, whether the fasteners are tight, whether the hydraulic Membrane Filter Press system is leaking oil, and whether the transmission parts are flexible and reliable.
4, often check the quality of hydraulic oil, oil level height is in line with the requirements, the oil is pure. The hydraulic system should be kept clean, waterproof and dustproof around.
5、After each start, carefully observe the working condition of the machine, if there is any abnormality, it should be stopped immediately for maintenance.
6、The oil temperature in the oil tank should not be higher than 60℃; water and dust are strictly prohibited in the oil tank; the oil filter on the hydraulic station should be cleaned frequently. Electrical control parts should be tested once a month for insulation performance, and damaged electrical components should be replaced or repaired in time.
7, machine use a month, should clean the oil tank, oil circuit, oil cylinder, etc., replace the qualified new oil, after every six months to replace, clean once.
8, when working filtering pressure, pressing pressure, material liquid temperature is not allowed to exceed the specified value, in the absence of plate frame or pressing plate maximum displacement is greater than the piston stroke, it is strictly prohibited to start the machine.
9、When starting the oil pump in winter, the hydraulic oil should be warmed up according to the need, and only put into use when the oil temperature rises above 15℃. Apply low condensation point hydraulic oil in alpine areas.
10、It is strictly forbidden to adjust the equipment in working condition, and it is strictly forbidden to start the machine if the pressure gauge is damaged or not equipped with a pressure gauge.
11、When replacing the new oil pipe for the first time, personnel should not be close to the high pressure oil pipe.
12, mechanical pressure filter press should pay close attention to the pressure situation, not long overload operation, so as not to burn the motor or damage parts.
13、Check and clean the inlet and outlet channels frequently to ensure unobstructed access.
14、When unloading slag, flush the filter cloth and plate frame as needed to ensure that the sealing surface is free of debris.
15, the relative movement of the parts, to regularly oil lubrication.
16、When the machine is out of use for a long time, it should be stored in a ventilated and dry room, the hydraulic system should be filled with oil, and other leaking processing surfaces should be coated with anti-rust oil. Storage should be placed in a sheltered place where the relative temperature is less than 80% and the temperature is -15-40℃ without corrosive media.
17、The filter plate and frame should not be in contact with oil, acid and alkali or other substances that are harmful to the plate and frame, and should be kept away from heat sources and avoid sun and rain.
18、When the diaphragm is pressed, the material must be filled with the filter chamber before pressing, and the filter plate must be opened for unloading only after the air has been exhausted after pressing, so as not to cause the diaphragm to break. The compressed air line should be checked frequently during work. If the air pipe falls off or leaks badly, the air inlet valve should be closed and the air release valve opened immediately. After repair, it can be used again. The actual operating instructions can be consulted with the manufacturer.
Working Principle Editor Podcast

Semi-automatic diaphragm filter press – compound rubber plate type
The main difference between the diaphragm filter press and the common chamber filter press is the addition of an elastic membrane diaphragm plate between the filter plate and the filter cloth. During the operation process, when the feeding is over, the high pressure fluid medium can be injected between the filter plate and the diaphragm, at which time the whole diaphragm will bulge and press the filter cake, thus realizing further dewatering of the filter cake, which is press filtration.
The first is positive pressure dewatering, also known as into the slurry dewatering, that is, a certain number of filter plates are closely lined up under the action of strong mechanical force, the filter plate surface and the filter plate surface between the formation of the filter chamber, the filter material under strong positive pressure is sent into the filter chamber, into the filter chamber of the filter material solid part by the filter media (such as filter cloth) to form the filter cake, the liquid part through the filter media and discharge the filter chamber, so as to achieve the purpose of solid-liquid separation, with the positive pressure pressure increases, solid-liquid separation is more complete, but from the energy and cost considerations, too high positive pressure pressure is not cost-effective.
After the pulp dehydration, the filter press equipped with a rubber squeeze membrane, the compression medium (such as gas and water) enters the back of the squeeze membrane to push the squeeze membrane to further dehydrate the squeeze filter cake, called squeeze dehydration. After pulp dehydration or extrusion dehydration, compressed air enters the filter chamber on one side of the filter cake through the filter cake and carries liquid water from the other side of the filter cake through the filter cloth to discharge the filter chamber and dehydration, called wind-blown dehydration. If both sides of the filter chamber are covered with filter cloth, the liquid part can be discharged from the filter chamber through the filter cloth on both sides of the filter chamber, which is called double-sided dewatering of the filter chamber.
After dewatering is completed, the mechanical compression force of the filter plate is lifted and the single piece is gradually pulled away from the filter plate and the filter chamber is opened separately for unloading the cake as a major work cycle is completed. Depending on the nature of the filter material, the filter press can be set up to feed pulp dewatering, extrusion dewatering, wind-blown dewatering or single or double-sided dewatering, with the aim of minimising the water content of the filter cake.