K-Patents has released a new application note on Pure Water Treatment by Chemical Precipitation. Pure water treatment is the process of removing undesirable chemicals, biological contaminants, suspended solids and gases from raw water. The purified water is then stored for human consumption, medical, pharmacological, chemical or industrial needs.
Polyaluminium coagulants are finding increasing use in potable water treatment plants, particularly, for soft, coloured surface waters. Polyaluminium chloride (PACl) is replacing the Alum (aluminium sulphate) which is also a commonly used coagulant in water treatment plants.
Water treatment by chemical precipitation is a complex process. It starts with adding flocculants, specifically, Polyaluminium Chloride (PACl) and Sodium Hydroxide (NaOH) into raw water. PACl is a synthetic polymer dissolved in water. It precipitates in big volumetric flocs which absorb suspended pollutants in the raw water. The amount of Polyaluminium Chloride to be added to the process is defined with regard to the turbidity of the raw water. In order to keep the flocculation process smooth, PACl concentration must be higher than 10%. When in the storage tank, Polyaluminium Chloride is stable, however, tends to crystallize after a period of time. K-Patents' refractometer allows for monitoring of PACl, informs about the necessity for the tank or pipe cleaning, and thus prevents them from blocking with the PACl crystals.