Common Filters' Principle and Application

The filter is a device that separates solid particles and liquid through porous media (filter cloth filter plate, etc.) by differential pressure. At present, the filter separator commonly used in concentrators are mainly divided into drum vacuum filters, disc vacuum filters, horizontal belt vacuum filters and filter presses. This article will introduce the working principle and scope of application of these 4 kinds of mining filters.

(1) Working Principle

The working principle is that the vacuum pump pumps a negative pressure on one side of the filter cloth to form a pressure difference between the two sides of the cloth. Thereby forcing the liquid in the slurry to pass through the filter cloth to become filtrate, and the solid particles that are retained on the filter cloth become filter cakes. The filtrate is continuously discharged from the machine, and the filter cake is removed with a scraper, thus forming a continuous filtration process.

(2) Application

Drum vacuum filter can be divided into outward filter, inward filter, fold belt filter and permanent magnetic outward filter. The inward filter is suitable for filtering materials with coarse particle size, higher density and faster sedimentation rate. It is mainly used to process magnetic separation and flotation iron ore concentrate. The outward filter and the fold belt filter are mainly used to filter non-ferrous metal and non-metal concentrates with fine particle size and low moisture content in the product. When filtering fine and viscous materials, pat device or compression roller can be added in the dehydration zone outside the drum to reduce the moisture of the filter cakes. Permanent magnetic outward filter is especially suitable for filtering coarse magnetite concentrate.

(1) Working Principle

The working surface of the disc vacuum filter separator is composed of a plurality of individual fan-shaped discs. Since the filter cloth covers the fan-shaped plates to form a filter chamber, each fan-shaped plate is a separate filter unit. When the filter is running, the filter disc rotates clockwise, and the solid particles of the slurry adhere to the filter disc by vacuum to form a filter cake. The filtrate penetrates into the filter disc through the filter cloth, and then the filtrate is discharged from the filtrate pipe, while the filter cake is discharged in the discharge area.

(2) Application

Disc vacuum filter is suitable for filtering fine-grained concentrates containing sludge, and is widely used for filtering iron concentrates.

(1) Working Principle

The filter medium of the horizontal belt vacuum filter is filter cloth, and the integral annular rubber belt is used as the vacuum chamber. The annulus rubber belt and filter cloth are continuously driven by the transmission device. The belt contacts the vacuum sliding table, then the slurry is evenly distributed on the filter cloth by the distributor.

When the vacuum system is running, the vacuum chamber forms a vacuum filtration zone on the rubber belt. The filtrate passes through the horizontal grooves of the filter cloth on the rubber belt and enters the vacuum chamber from the central hole, while the solid particle is retained on the filter cloth to form a filter cake. With the movement of the rubber belt, the formed filter cake is gradually dried by the influence of pressure difference, and the filter cake is discharged at the discharge port; at the same time the liquid entering the vacuum chamber is discharged through the air water separator. After removing the filter cake, the filter cloth can be reused after cleaning

(2) Application

The horizontal belt vacuum filter is suitable for filtering coarse and dense minerals such as coal ore.

(1) Working Principle

The hydraulic cylinder of the filter press presses all the filter plates between the movable head plate and the fixed tail plate, so that the adjacent filter plates form filter chambers. The filtrate enters each filter chamber from the feed hole, and through the filter cloth, the solids are trapped in the filter chamber and gradually form filter cakes; the liquid is discharged out of the machine through the water outlet hole on the plate frame.

(2) Application

The filter press is mainly used to filter the filtrate with fine particles and high viscosity. It is widely used in the filtration process of fine-grained concentrates, gold cyanide tailings, and displacement of gold.

The above is the working principle and scope of application of four common filter separator: drum vacuum filters, disc vacuum filters, horizontal belt vacuum filters and filter presses. In actual production, the appropriate filters should be selected according to the needs of the project. If you want to know more about the mining filters, you can consult online customer service or leave a message, we will contact you as soon as possible!