Polyaluminium chloride is a well-known water treatment agent. It is used for sewage treatment at a low price and achieves a treatment effect. How about decolorization for sewage treatment?

The flocculation and decolorization mechanism of wastewater is based on the theory of adsorption bridge. In the case of inorganic flocculants, the flocculating agents such as iron and aluminum are hydrolyzed and polymerized to form high-priced polyhydroxy cations, which are compressed with water colloids, electrically neutralized, destabilized, adsorbed and bridged, and supplemented by The sediment net is trapped and rolled, and the coarse flocs formed by the precipitation are removed to achieve the purpose of decolorization of the purified water. For organic polymer flocculants, in addition to electrical neutralization and bridging, there may be a flocculation mechanism similar to chemical reaction bonding.

In view of the difficulty in decolorization of wastewater, the current treatment method adopted in the market is: when the amount of polyaluminium chloride is 0.05%, the decolorization effect on the five types of dyes is good. In addition, increasing the amount of polyaluminium chloride added can improve the decolorization effect. For example, for dyeing wastewater containing sulphur dyes and nafto dyes, when the dosage of polyaluminium chloride is increased to 0.08% and 0.1%, the decolorization efficiency will be increased to 81% and 90%, but the treatment cost will also be corresponding. increase. If the use of the polyaluminium chloride and the polyacrylamide will greatly reduce the dosage of the polyaluminium chloride, the treatment effect can also be achieved.