Water purification of a new type composite inorganic polymer coagulant--polyaluminum silicate chloride (PASC)
新型复合无机高分子混凝剂——聚硅氯化铝(PASC)的净水效果研究

Polyaluminum silicate chlorides (PASC), with different bacisities ( B ) and Al/Si molar ratio, were prepared by hydroxylation of the mixture of AlCl\-3 and fresh polysilicate. The differences in the coagulation performance for water treatment and the residual aluminum content between PASC and polyaluminum chloride (PAC) were compared. The effect of B and pH value on the residual aluminum content of PASC and PAC in the treated water was studied. The influence of the Al/Si molar ratio on the coagulating effect and the residual aluminum content of PASC was also investigated. The experimental results showed that PASiC is superior to the PAC in terms of the coagulating performance and the decreasing residual aluminum content in treated water. For higher turbid water, the PASiC with proper Al/Si molar ratio gives better coagulation effect, however, in the tested range of Al/Si ratio for medium and lower turbid water and the oil\|containing wastewater, the lower Al/Si molar ratio, gives better the coagulating effect. The residual aluminum of PASC in the treated water decreases with decrease of Al/Si molar ratio and increasing of B value. PASC and PAC give the lowest residual aluminum concentration in neutral pH range.