Refined quartz sand filter material is suitable for drinking water filtration and other water purification treatment. It is more suitable for the pre-treatment and circulating water treatment of dry petroleum, mining, metallurgy, thermoelectricity, paper making, printing and dyeing, tannery and other production water, as well as the recycling and utilization of sewage.
　　technical requirement
　　1) The sum of mechanical strength, breakage and wear rate should not be greater than 1.5% (percentage by weight).
　　2) The chemical property is stable. There are no visible clay, mica and organic impurities. The water leaching solution of the filter material does not contain toxic and harmful substances.
　　3) The density of quartz sand should not be less than 2.55g/cm3. Except for those with special requirements for density in use.
　　4) The burning weight loss of quartz sand filter material should not be greater than 0.7%, and the solubility of hydrochloric acid should not be greater than 1.5% (Ministry Standards).
　　5) Mud content should not be greater than 1%, and light substances with density less than 2g/cm3 should not be greater than 0.2% (Ministry Standards).
　　6) The size distribution is reasonable, and the appearance is polygonal, monologue and lustrous crystal. The particle size range of single-layer or double-layer filter media is generally 0.5-1.2 mm. The particle size range of three-layer filter media is generally 0.5-0.8mm.
　　7) The particle size range smaller than the specified lower limit is not more than 3% by weight, and the particle size larger than the specified upper limit is not more than 2%.
　　8) The particle size range of quartz gravel supporting layer is generally 2-4, 4-8, 8-16, 16-32 and 32-64 mm. The product packaging is usually 50 kg bags or ton bags.