What You Need To Know About The Plate And Frame Filter Press

The plate and frame filter press is a batch filtration device that achieves solid-liquid separation through mechanical pressure. It consists of alternately arranged filter plates, filter frames, and filter cloths, forming a sealed filter chamber. Thanks to its unique mechanical structure and separation mechanism design, it can separate suspensions into high-dryness filter cakes and clear filtrate under high pressure. In this post, YW-well Filter will discuss everything about the plate and frame filter press.

Plate and Frame Filter Press structure 

Core Structural Components

Filter Plate

• Structural Features: The surface contains precisely calculated concave and convex patterns, forming a liquid-guiding groove system.
• Core Functions: The convex parts support the filter cloth to prevent collapse, and the concave grooves guide the rapid collection and discharge of filtrate; ensure the utilization rate of filtration area and the flow efficiency of filtrate, and are the basis for continuous filtration.

Filter Frame

• Structural Features: A hollow frame whose volume is determined by its thickness; a suspension inlet is set at the center.
• Core Functions: Serve as a filter cake carrying space, and the greater the thickness, the stronger the single processing capacity; enable the material liquid to diffuse under pressure through the central inlet, contact with the filter cloth to complete the initial solid-liquid separation.

Filter Cloth

• Structural Features: A filtration medium clamped between the plate and frame, with a fine fiber structure, and the material and pore size can be customized.
• Core Functions: Trap solid particles and allow liquid to pass through to form filtrate; need to match material characteristics (e.g., high-density cloth for fine particles, smooth material for high-viscosity materials), which directly affects filtration efficiency and filtrate quality.

Pressing Device

• Types:
• Hydraulic system: The oil pump provides stable pressure, suitable for large-scale equipment or high-pressure scenarios.
• Manual screw system: The rotating handle drives the screw rod, with a small pressure adjustment range, suitable for small-scale / intermittent operations.
• Core Function: Apply uniform pressure to make the plate and frame fit closely, forming a sealed filter chamber and providing a stable space for separation.

Plate and Frame Filter Press Working Principle

1. Chamber Compression 

The pressing mechanism compresses alternating plates, frames, and filter cloth into a series of sealed chambers. 

2. Slurry Feeding & Filtration 

The slurry is pumped under high pressure into the central feed port of the filter frame. Liquid passes through the filter cloth, while solid particles are intercepted by the cloth, accumulating within the frame to form a filter cake. The filtrate flows downward through the drainage channels of the filter plates and exits via the bottom outlets. 

3. Cake Formation & Resistance Dynamics 

In the initial stage, the filtrate flow rate is rapid; in the mid-to-late stages, as the filter cake thickens, the filtration resistance increases significantly, resulting in a substantial drop in flow velocity.

4. Cake Discharge & Cleaning 

Stop feeding, release pressure. Loosen pressing mechanism,separate plates/frames. Manually/mechanically remove cake, clean cloth and components.

Application Fields of Plate and Frame Filter Press

1. Mining and Metallurgy

• Concentrate dewatering
• Tailings treatment
• Precious metal recovery

2. Chemical Industry and Pharmaceutical

• Fine chemicals
• Bulk pharmaceutical production
• Biological agents

3. Environmental Protection and Sludge Treatment

• Municipal sludge
• Industrial hazardous waste:
• Sewage pretreatment

4. Food and Beverage

• Edible oil refining:
• Fermentation broth clarification:
• Gelatin/pectin extraction: