The colors of polymeric chlorinated aluminum generally include white, yellow, and brownish-red, with significant differences in application and supplier technology among different colored polymeric chlorinated alums. In China, the standard range for the content of aluminum trioxide is between 27 to 30, with most being solid powder in shades of yellowish-brown, light yellow, or yellow. These types of polymeric chlorinated aluminum have good water solubility, accompanied by electrochemical, coagulation, adsorption, and precipitation physical and chemical changes during dissolution, forming fast and large flocs with high activity, quick settling, and obvious purification effects on high turbidity water.
White polymeric chlorinated aluminum is known as high-purity iron-free white polymeric chlorinated aluminum and is a product of high quality compared to other polymeric chlorinated alums. It is used in various fields such as paper sizing agent, sugar decolorization clarifier, tanning, pharmaceuticals, cosmetics, casting, and water treatment. Yellow polymeric chlorinated aluminum is made from aluminum hydroxide powder, hydrochloric acid, and bauxite, mainly used for sewage treatment and drinking water treatment. Regarding drinking water treatment, China has strict requirements for heavy metals, so both raw materials and supplier processes are better than brownish-red polymeric chlorinated aluminum.
Polymeric chlorinated aluminum not only differs in color but also in form, specifically divided into two types: solid and liquid. Liquid polymeric chlorinated aluminum is in an undried state and has the advantages of no dilution required, convenient loading and unloading, and relatively cheap price. The disadvantage is that transportation requires tank trucks, increasing the unit transportation cost (each ton of solid is equivalent to 2-3 tons of liquid), making it suitable for users within a 100 km radius. Solid polymeric chlorinated aluminum is the dried form of liquid polymeric chlorinated aluminum and has the advantage of convenient transportation without tank trucks. However, it still needs to be diluted when used, increasing work intensity.
Regardless of the type of polymeric chlorinated aluminum, all can be used as purifying materials in sewage treatment and can bring assistance to our wastewater treatment industry.
