高浓度聚铝硅的制备及其混凝性能

采用稳定高浓度偏铝酸钠,与硅酸钠、硫酸铝等合成得到3个系列共15个澄清稳定的高浓度聚铝硅(HPASS)产品,pH为3.15～3.63,密度为1.20～1.28 g/mL,盐基度为65.90%～72.93%,Al2O3质量分数可达8.21%～10.84%.而Handv公司已工业化的产品PASS-100,Al2O3质量分数为10.1%,盐基度约为50%;国内Al2O3质量分数最高的PASS产品只能达到8%左右,盐基度为40%～60%.HPASS与PAC和聚铝铁(PAFC)的混凝性能对比实验发现,HPASS在投加质量浓度为7 mg/L(以Al2O3计)时,浊度去除率可达90%以上;当达到各自的最佳投加量时,HPASS处理后出水的浊度均《1 NTU.最低可达0.5 NTU,而PAC和PAFC分别为1.3、1.1 NTU.

Preparation of highly concentrated polyaluminium silicate sulphate and its coagulation performance

The stable and highly concentrated sodium meta-aluminate has been used to synthesize with sodium silicate and aluminum sulfate,thus,3 series of 15 clear and stable highly concentrated polyaluminium silicate sulphate(HPASS)are obtained.Their pH are 3.15-3.63,densities are 1.20-1.28 g/mL,basicities are 65.90%-72.93%,and contain 8.21%-10.84% of Al2O3,while the industrialized product of Handy Co.PASS-100 contains 10.1% of Al2O3 and its basicity is just about 50%;and the highest concentration of PASS reported in China is just about 8%,and the basicities are 40%-60%.Compared with polymeric aluminum chloride(PAC)and polymeric aluminum ferric chloride(PAFC),it is found that when the HPASS dosage is 7 mg/L(Al2O3),its turbidity removal ratio is higher than 90%;when under their optimal dosages,the residual turbidity of effluence treated by HPASS is lower than 1 NTU,the lowest can be 0.5 NTU,while PAC and PAFC can be 1.3 NTU and 1.1 NTU respectively.