Quartz sand filter, the scientific name of shallow media filter, uses quartz sand as the filter medium. Under a certain pressure, water with higher turbidity is filtered through a certain thickness of granular or non-granular quartz sand, effectively intercepting A high-efficiency filtration equipment that removes suspended solids, organic matter, colloidal particles, microorganisms, chlorine, smell and some heavy metal ions in the water, and finally achieves the effect of reducing water turbidity and purifying water quality.

The activated carbon filter can absorb the residual chlorine that cannot be removed in the previous stage filtration to prevent the subsequent stage reverse osmosis membrane from being oxidized and degraded. At the same time, it also adsorbs pollutants such as small molecular organics leaked from the previous stage, which will affect the peculiar smell, colloids and pigments in the water. Heavy metal ions, etc. have obvious adsorption and removal effects, and also have the effect of reducing COD. The SDI value of RO influent can be further reduced to ensure SDI<5 and TOC<2.0ppm.