Box-type Pressure Filter

Detailed Description
The working principle of the box filter press consists of filter plates arranged to form filter chambers (with the filter plates having concave sides, each pair of plates combining to create a box-shaped filter chamber).

Principle
The filter plates have surface grooves and bosses to support the filter cloth. There are through-holes in the center and corners of the filter plates, which, upon assembly, form a complete passage for the suspension liquid, washing water, and extraction of the filtrate. Handles on both sides of the filter plates are supported by crossbeams and are clamped to the plates by a clamping device. The filter cloth between the plates serves as a seal.
Under the pressure of the feed pump, the material liquid to be filtered is sent into each filter chamber. It is separated into solid and liquid through the filter medium (suitable filter cloth selected based on different industries). The filter cake is formed on the filter cloth until it fills the filter chamber. The filtrate passes through the filter cloth and flows along the groove of the filter plate to the lower outlet channel, where it is discharged collectively. After filtration, the filter cake can be washed with cleaning water. Sometimes, compressed air is introduced after washing to remove any remaining cleaning liquid. At the end of the filtration, the pressure filter is opened to remove the filter cake (stored between adjacent filter plates), clean the filter cloth, and then re-tighten the plate filter to start the next working cycle.
The chamber filter press operates on a plate-and-frame filter chamber, consisting of a flat plate filter and a hollow frame. The filter cloth is fixed to the plate frame, which was the primary form of early filter presses. The main advantage of the chamber filter press is the ease of replacing the filter cloth, but it has drawbacks such as low efficiency, poor filtration, and fragile filter plates. The filter chamber of the chamber filter press is formed by two adjacent concave filter plates, with the filter cloth fixed on each plate. The main advantage is higher efficiency, better results, and relatively durable filter plates (under the same conditions). The drawback is that replacing the filter cloth can be a bit cumbersome, but with high automation levels and automatic cleaning devices for the filter cloth, the frequency of filter cloth replacement is generally not high.
The primary advantages of this model include minimal material loss during feeding, rapid filtration speed, high resistance to high temperature and pressure, excellent sealing performance, uniform washing of the filter cake, low moisture content, and uniform pressure across all filter chambers, which makes it less prone to damage. It is basically suitable for all solid-liquid separation industries.