Multi-disc Vacuum Filter

Multi-disc Vacuum Filter

Multi-disc vacuum filter is a new-generation pulping equipment. It is mainly used for white liquor recovery and pulp refining. It can save energy and water consumption, lower fiber loss, protect environment and avoid pollution.

AGICO disc filter can manufacture pulp density and processing capacity according to technical requirements from the customer. AGICO owns mature technology and newest design software. Our products have occupied the majority market share in China.

disc filters
disc filter

Disc filter series and specifications:

Overall dimension L*W*H(mm)Overall dimension L*W*H(mm)Overall dimension L*W*H(mm)Overall dimension L*W*H(mm)
16 8310*4100*53619119*5450*60609515*6400*7235
18 9010*4100*53619819*5450*606010215*6400*7235
20   10915*6400*7235
22   11615*6400*7235


Disc Dia. (mm)2500350045005500
Per-disc filtration area (m2)8.516.72638
Capacity0.6-3M3/m3.h (white water recovery)
0.7-1.5t/m3.d (pulp thickened)
Fiber recovery rate (%)>95
Filtrate clarity(mg/L)20-80
Inlet consistency (%)0.2-0.6(white water recovery)
0.5-1.2 (Pulp thickened)
Outlet consistency (%)4-6(white water recovery)
4-15 (Pulp thickened)
MOCSS304 material for parts in contact with product
Vacuum degree (Mpa)0.02-0.06
Net washing water pressure (Mpa)0.7
Stripping water pressure (Mpa)0.7

Working principle

White liquor enters the multi-disc filter through the feeding box and distributes evenly in the tank. By gravity action, the pulp layer (2-3mm) will be formed on the fan. To ensure the best dewatering operation, the filtrate will be discharged to the corresponding channel at the central axis through the fan equipped with open grille.

The rotary shaft is linked with a filtrate valve that can switch on or off relevant vacuum channel. Vacuum is formed by atmospheric water loss. When it enters the valve, the filtrate will be classified into turbid filtrate, clear filtrate and ultra clear filtrate.

When the fan emerges from the suspension, the filtrate is expelled out, and the pulp layer is dehydrated under vacuum state. The pulp will be stripped off from the fan by spraying pipe, which is set into the discharge channel in the tank side by side, and then sent to the screw conveyor. The filter screen will be washed clean by the vibration pipe before the next cycle begins.


In the process of white liquor recovery, water recycle is realized and water consumption is reduced. The fiber recovery rate is high, and waste and pollution are eliminated when white liquor is discharged. When the pulp is thickened, the pulp concentration is high, reaching 10%.-14%.

The filter plate has the features of diversified structure, economical application, high strength, convenient displacement, large effective filtration area and good filtration effect. The model and specification of equipment is complete, a client can select his product according to different requirements. Due to special wear-resistant material distribution plate, the filter has good sealing effect. The filter also has high automation and reliable performance with compact structure, small occupied area and large production capacity, so it gets easy to operate, bringing us good economic and social benefits.

Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibres from wood, fiber crops, waste paper, or rags. Many kinds of paper are made from wood with nothing else mixed into them. This includes newspapers, magazines and even toilet paper. Pulp is one of the most abundant raw materials.

A pulp mill is a manufacturing facility that converts wood chips or other plant fibre source into a thick fibre board which can be shipped to a paper mill for further processing. Pulp can be manufactured using mechanical, semi-chemical or fully chemical methods (kraft and sulfite processes). The finished product may be either bleached or non-bleached, depending on the customer requirements.

A paper machine (or paper-making machine) is an industrial machine which is used in the pulp and paper industry to create paper in large quantities at high speed. Modern paper-making machines are based on the principles of the Fourdrinier Machine, which uses a moving woven mesh to create a continuous paper web by filtering out the fibres held in a paper stock and producing a continuously moving wet mat of fibre. This is dried in the machine to produce a strong paper web.

The pulp produced up to this point in the process can be bleached to produce a white paper product. The chemicals used to bleach pulp have been a source of environmental concern, and recently the pulp industry has been using alternatives to chlorine, such as chlorine dioxide, oxygen, ozone and hydrogen peroxide.

Chemical pulp is produced by combining wood chips and chemicals in large vessels called digesters. There, heat and chemicals break down lignin, which binds cellulose fibres together, without seriously degrading the cellulose fibres. Chemical pulp is used for materials that need to be stronger or combined with mechanical pulps to give a product different characteristics. The kraft process is the dominant chemical pulping method, with the sulfite process second. Historically soda pulping was the first successful chemical pulping method.