Filter Cloth Applied on Wood Industry

Filter Cloth Applied on Wood Industry

Application of filter cloth in wood and wooden board manufacturing

In modern wood industry, from particleboard, MDF/HDF, to oriented strand board (OSB), the efficiency and quality of board production increasingly depend on the stability of front-end fiber treatment. In this system, there is a link that is often overlooked but almost determines key indicators such as the moisture content, strength, and uniformity of the wooden board - the application of filter clothin the belt press filter machine.

What are the difficulties in solid-liquid separation of wood fiber pulp?

The characteristics of wood fibers themselves determine that dehydration is not easy:

Fibers are soft and have a large specific surface area, making them prone to clumping and forming a water lock structure.

High pulp concentration and viscosity → require higher mechanical dewatering pressure.

Containing small particles and gelatinous substances → prone to clogging traditional filter cloth.

Different tree species and regions have significant differences in fiber content, resulting in noticeable fluctuations in filtration conditions.

In density board, particle board, and fiberboard factories, the ability to press and dehydrate directly affects:

1.Energy consumption (drying section accounts for 40% -60% of total energy consumption).

2.Uniformity of board density.

3.Adhesive distribution.

4.Press cycle and production capacity.

So, whether the wooden board industry runs fast or not largely depends on whether the filter cloth and mesh used in the squeezing and filtering process are professional enough.

The three major functions of filter cloth in belt press filter machine

(1) Filtration: Drain the water and retain the fibers

Wood pulp has a wide particle size distribution and contains gum. If the filter cloth design is not reasonable, it may result in:

-Fiber loss

-Difficulty in forming filter cake

-The filtering speed slows down

-Mesh blockage

Professional filter cloth can ensure:

-High interception rate

-Smooth surface and uniform filter cake

-Smooth drainage to ensure high-speed operation

(2) Supporting capacity: allowing fibers to maintain their structure under high pressure

During the pressing stage, the filter cloth is not subjected to tens of newtons of tension and squeezing force, but hundreds or thousands of newtons.

High quality filter cloth must:

-High tensile strength, no deformation, no deviation

-Resistant to high pressure and repeated squeezing

-Resistant to steam, temperature, and adhesive corrosion

Otherwise, it will affect the pressing efficiency, dehydration rate, and even lead to frequent shutdowns.

(3) Drainage: Multi dimensional drainage structure enhances the ability to control moisture content

The new generation of belt press filter cloth adopts:

-multi-layer structure

-Monofilament+double-layer composite mesh

-Special surface weaving

-Optimized drainage channels

These designs can significantly improve drainage speed and make the moisture content of the filter cake more stable.