Diaphragm Filter Plate

Diaphragm Filter Plate

The diaphragm filter plate consists of two diaphragms and a core plate. When an external medium, such as water or compressed air, is introduced into the chamber between the core plate and the diaphragm, the diaphragm inflates and compresses the filter chamber formed by the diaphragm filter plate and the chamber filter plate. This process enhances separation efficiency and increases the solid content of the filter cake. As the membrane is the primary moving component, its repeated movement can lead to deformation and eventual damage.

The rubber diaphragm in a filter plate is typically embedded within the groove of the core plate, making it easy to disassemble and replace. Due to its high elasticity, the rubber diaphragm is resistant to damage. In contrast, polypropylene filter plate diaphragms are usually welded as an integrated unit, and once welded, the diaphragm cannot be replaced. The membrane filter plate is usually used in conjunction with the ordinary chamber filter plate. The two filter plates are placed crosswise on the membrane filter press.

Working Principle of Membrane Filter Plates

In contrast to the filter plates of chamber filter presses, membrane filter plates have a flexible filter surface, the membrane. While in pressure filtration, the dewatering of the filter cake occupies a relatively inefficient process stage, in filtration using membrane technology this process is replaced by simple squeezing. By injecting a pressurized medium, such as compressed air or water, behind the flexible membranes, they expand outwards. In this process, the filter cake in the filter chamber is pressurized and squeezed over the entire surface. This approach not only significantly shortens filtration cycles across nearly all filtration applications but also achieves a higher dry matter content.

Additionally, if cleaning the filter cake is required, the membrane offers a clear advantage in this process. During the cleaning process, the filter cake is stabilized in the filter chamber by the continuous pressurization of the membrane. Further squeezing of the filter cake after the washing cycle results in exceptionally high dry matter content, which would otherwise require prolonged dry blowing to achieve.

Advantages of Diaphragm Filter Plates

High-efficiency filtration: diaphragm pressing can significantly increase the solid content of the filter cake, reduce the residual amount of filtrate, and reduce the drying cost.

Energy saving: Mechanical pressing instead of long-term filtration can shorten the filtration cycle, and save electricity and operating time.

Wide range of applications: It can adapt to a variety of materials, including high-viscosity slurries, suspensions with high solid content, and even compressible particles.

Reduce filter cloth wear: When the diaphragm is pressed, the filter cloth is evenly stressed, which can extend its service life and reduce operating costs.

Strong flexibility: Gas or liquid can be used as the medium, and the specific choice depends on the process requirements.