研究生物法制备铁系絮凝剂及其影响因素。以FeSO4·7H2O为原料,利用驯化后的氧化亚铁硫杆菌(T·f)在酸性条件下的催化氧化作用制备生物聚合硫酸铁(PFS),并确定最佳制备条件。实验表明:在反应液初始pH值1.5、硫酸铵用量0.5g/L、初始Fe2+浓度45g/L、接种量10%、温度30℃时,在转速为120r/min的恒温水浴摇床中连续培养5~6d、可以制出pH1.5~2.2、盐基度17.5%~22.7%、全铁含量43.87~45.24g/L的产品。实验通过处理3种废水来考察其絮凝性能,结果表明:当PFS投加量一定时,COD去除率可达70%以上,脱色率达90%,Zn2+去除率达99%,说明PFS是一种絮凝效果优异的水处理剂。
A novel inorganic polymer flocculant,poly-ferric sulfate(BPFS) was prepared by oxidation of ferrous sulfate using domestic Thiobacillus ferrooxidans(T·f) under acid condition.The optimal conditions for the preparation were pH value of 1.5,(NH4)2SO4 dosage of 0.5 g/L,initial Fe2+ concentration of 45g/L,inoculum 10%,rotating speed of 120 r/min,reaction time of 5-6 d and reaction temperature of 30 ℃.Under the optimal conditions,the BPFS product with pH value of 1.5-2.2,basicity of 17.5%-22.7% and total iron content of 43.87-45.24 g/L was obtained.The application of the BPFS to three wastewaters was carried out,and the removal efficiencies of COD,decolorization and Zn2+ by BPFS can be reached 70%,90% and 99%,respectively.The result suggests that the BPFS is an excellent flocculant for water treatment.