Principles And Applications Of Filter Press Water Treatment

A filter press machine plays a vital role in filter press water treatment by effectively handling the challenge of extracting water from sludge, transforming it into solid, manageable filter cakes. But how does a filter press work, and what makes it indispensable? This post from YW-wellfilter explores the filter press working principle, deciphers the filter press diagram, and highlights the advantages of different types of filter press systems.

What is Filter Press Machine

The filter press is an extremely important solid-liquid separation equipment in Filter Press Water Treatment. Its core function is to separate suspended solids in water through physical pressing and filtration, thereby obtaining solid filter cakes with low water content and relatively clear filtrate.

In the process of water treatment, a large amount of sludge is generated. This sludge has high water content, large volume, and is difficult to transport, dispose of and recycle. However, Filter Press Water Treatment can remove most of the water from this thin sludge, forming mud cakes with extremely low water content, which greatly reduces the volume and weight.

Filter Press Water Treatment is widely used in municipal sewage treatment plants, industrial wastewater treatment, waterworks, river and lake dredging sludge dewatering and other fields.

The use of Membrane Filter Press for Filter Press Water Treatment has become the absolute mainstream, and the core reason lies in their solution to the dual challenges of deep dehydration and cost-effectiveness that traditional dehydration equipment could not overcome.

Filter Press Diagram

1. Filter Press Frame：

• Composed of head plate, tail plate, and beams.
• Function: Supports the filter plate assembly and withstands high pressure.

2. Filtration Unit：

• Consists of filter plates, filter cloth, and membrane (core components).
• Function: Forms filter chambers, retains solids, and enables deep dewatering.

3. Power System：

• Hydraulic station + high-pressure oil cylinder.
• Function: Provides plate-clamping force and ensures sealing.

4. Control System：

• PLC, sensors, and HMI (Human-Machine Interface).
• Function: Automates feeding, squeezing, and cake discharge processes.

Filter Press Working Principle

1.       Filtration Stage：

Sludge is pumped into sealed chambers formed by filter plates. Under high pressure, liquid passes through the filter cloth while solids are retained, forming a filter cake – a fundamental process in Filter Press Water Treatment.

2.       Membrane Squeezing Stage(deep dehydration)：

An elastic membrane expands to compress the cake, disrupting bound-water structures and significantly reducing moisture content.

3.       Automatic Discharge & Cleaning：

Filter plates open to release the dewatered cake, followed by automatic cloth washing for regeneration.

Types of Filter Press

1.       Membrane Filter Press

• Structure: Recessed plates with embedded elastic membranes, creating squeeze chambers.
• Function:
• Secondary High-Pressure Squeeze: Compressed air/water inflates membranes to compress cakes.
• Critical Advantage: Reduces cake moisture below 60%, making it essential for modern Filter Press Water Treatment.

2.       Plate and Frame Filter Press

• Structure: Alternating rectangular filter plates and hollow frames covered with filter cloth.
• Function: Forms sealed chambers; liquid flows through plates while solids accumulate in frames.

3.       Chamber Filter Press

• Structure: Single recessed plates with dual-sided filter cloth, forming chambers when compressed.
• Function:
• Superior sealing and higher pressure tolerance vs. plate-frame type.
• Centralized filtrate discharge via plate channels.