The multi-media filter is a typical multi-media filter whose bed is made of anthracite, sand, fine garnet or other materials.
The principle of the equipment is that when the raw water passes through the filter material from top to bottom, the suspended solids in the water will be intercepted by the surface of the filter layer due to adsorption and mechanical resistance; When the water flows into the middle of the filter layer, because the sand particles in the filter layer are arranged more closely, the particles in the water have more chances to collide with the sand particles, so the flocs, suspended solids and sand particles in the water adhere to each other, and the impurities in the water are trapped in the filter layer, so as to obtain the clarified water quality. The suspended solids in the filtered effluent can be less than 5 mg / L.
1. Porous media filters are widely used in water treatment process, and can be used alone, but most of them are used as pre filtration for advanced water treatment.
2. Multi media filter is a common pretreatment device for deep purification of water quality, which can be filled with different filter materials according to the process requirements.
3. The material of multi-media filter can be glass fiber reinforced plastic, A3 steel anti-corrosion or rubber lining, all stainless steel. There are two kinds of operation modes: automatic control and manual control. The automatic control is controlled by the automatic controller and pneumatic and hydraulic valves imported from the United States. It is easy to operate and maintain. It is widely used in the pretreatment devices of water treatment process in all walks of life.
4. The filter material of multi-media filter should have enough chemical stability, and the relative density and particle size of each medium should be different. The relative density of anthracite used in the double-layer filter material composed of anthracite and quartz sand is 1.4-1.6, the particle size is 0.8-1.8mm, and the relative density of quartz sand is 2.6-2.65, the particle size is 0.5-1.2mm; In addition to the above two kinds of filter media, the three-layer filter media can also use heavy ores such as manganese sand and magnetite with relative density of 4.7-5.0 and particle size of 0.5-4mm.