基于常规净水工艺的强化混凝除锑生产性试验研究

摘要

A series of full-scale experimental study were conducted to remove antimony from water using en-hanced coagulation technology in conventional water treatment processes of drinking water plant (i.e., folded-plate flocculating tank—horizontal flow sedimentation tank—siphon filter),with the aim of coping with frequently excessive concentration of antimony in some part of Zijiang River as a drinking water source.The re-sults showed that adding polyferric sulphate (PFS)can effectively remove antimony from water,and an excessive dosage of PFS can not markedly affect the regular water quality indexes of drinking water.When the dosage of PFS is 12.3~21.7 mg/L,adding hydrochloric acid can produce treated water with antimony concentration less than 5 μg/L to meet the Standards for drinking water quality (GB 5749-2006).Moreover,if hydrochloric acid is added,the cost of chemicals can be cut down by reducing the dosage of PFS.The most economic dosing scheme is to add 12.3 mg/L PFS,followed by 73.3 mg/L hydrochloric acid,which can be considered as a guidance for removing antimony in a drinking water plant with chemical cost of 0.385 YUAN/m3 .%针对资江某段水源水中重金属锑含量经常性超标问题,采用强化混凝技术在自来水厂常规水处理工艺(折板絮凝池-平流沉淀池-虹吸滤池)中进行除锑生产性试验研究。结果表明,絮凝剂聚硫酸铁(PFS)可以有效去除饮用水中的锑,且过量投加 PFS 不会对饮用水常规性指标造成显著影响；PFS 投加量为12.3~21.7 mg/L 时,再投加盐酸,可使出水锑含量满足《生活饮用水卫生标准》(GB 5749-2006)中锑限值为5μg/L 的规定,且可以通过增加盐酸投量以减小 PFS 投量,从而降低药剂成本；最经济的投药方式为：投加12.3 mg/L PFS 的同时再投加73.3 mg/L 盐酸,此时的药剂成本为0.385元/m3,可以此投加方式指导水厂进行除锑生产。