Filtration as a conventional treatment process for water treatment,Plays a role in effectively reducing turbidity in domestic drinking water and industrial water treatment.The material used for filtration is called Water filter media.
The water flows through the filter layer composed of filter material, in which the impurities contained in the water flow are intercepted in the gap of the filter material under the action of the filter layer. As the porosity of the filter material becomes smaller, the smaller suspended particles are also intercepted. At the same time, the flocs intercepted on the surface of the filter material contact with the suspended particles in the water to purify the water. The types of filter materials include quartz sand, anthracite, activated carbon, ceramsite, garnet, fiber ball, etc.
Application of filter material
It is made of natural quartz ore by crushing, screening and washing. The appearance is polyhedral, spherical, pure white, with high mechanical strength, strong ability to intercept pollution, stable chemical properties and so on. The service life of quartz sand is 3-4 times longer than that of natural sea sand and river sand, and the water quality is stable after filtration. At present, the most widely used and the largest amount of filter media.
The fine anthracite filter material is made of high-quality anthracite, which is selected, crushed, and sieved twice. It has good gloss, spherical shape, high mechanical strength, good compression resistance, stable chemical performance, no toxic substances, and resistance. Abrasion, insoluble in acidic, neutral and alkaline water. In addition, the surface of anthracite particles is rough and has good adsorption capacity. The porosity is large (>50%), and it has high contamination capacity. Need to backwash low strength, can save a lot of backwash water.
Garnet is a mineral product formed from aluminum (calcium) silicate. It has the characteristics of high hardness, high melting point, high density, good chemical stability, and moderate porosity. It is a new type of wear-resistant water purification material. In the field of sewage treatment, it is widely used as high-density filter material, such as the heavy-media filter material of the three-layer filter material filter, which can fully exert the interception ability of the filter bed, the filtration cycle is long, and the high turbidity or turbidity fluctuation The adaptability of the water source into the water is strengthened.
Ceramsite uses natural minerals or industrial waste as the main raw material, which is directly crushed or processed into granules and then swelled. The ceramsite filter material is porous, has a large specific surface area, strong adsorption capacity, and good chemical stability. Its specific surface area is 6-8 times that of quartz sand, and its porosity is 1.7-2.2 times that of quartz sand.
Compared with the traditional steel granular filter material, the fiber ball filter material has the advantages of good elastic effect, no floating on the water surface, large gap, long working cycle and small head loss, which is suitable for filtration of various water quality.
Rare earth porcelain sand
It is made of high-quality kaolin clay and a certain amount of binder and other raw materials by dry roasting and processing. It is spherical particles, with high mechanical strength, large specific surface area, low wear rate, excellent adsorption performance, and strong interception ability. The sewage treatment effect is good.
Activated carbon uses high-quality wood chips as raw materials, and is produced by the zinc chloride method. It has developed pore structure, large specific surface area, strong adsorption capacity, high mechanical strength and good chemical stability.
The development of filter media
The research of filter media is developing in the direction of stable physical and chemical properties, safe and non-toxic, high porosity, large specific surface area, strong adsorption capacity, convenient backwashing and water saving.