改性累托石复合絮凝剂用于给水处理的研究

目前我国自来水厂所用的多为水溶性聚铝类絮凝剂,这就不可避免地使自来水中存在相当浓度的铝离子,而长期摄入铝离子会导致多种疾病.通过对天然累托石进行钠化和铝交联改性,并与天然有机高分子助凝剂复合,制备出一种成本低、铝含量较少的新型絮凝剂.应用于给水处理的试验结果表明,与传统的聚合氯化铝（PAC）相比,其出水浊度和铝离子含量分别下降了9.5%、53%,并且降低药剂成本约9.5%,具有明显的经济与环境效益.此外,还对该絮凝剂的絮凝机理进行了探讨.

Study on Application of Modified Rectorite Composite Flocculant in Water Treatment

Polyaluminum chloride(PAC) is currently a flocculant used in the Chinese waterworks,but using PAC will bring some Al~(3+) ions into the tap water,leading to many diseases brought from aluminum.By modifying rectorite using Na_2CO_3 and AlCl_3,and making a composition between modified rectorite and natural organic polymer flocculant aid,a novel flocculant was prepared.This flocculant is of lower cost and Al~(3+) ion concentration than PAC.The turbidity degree,Al~(3+) ion concentration and cost of this flocculant are reduced by 9.5%,53% and 9.5% respectively,compared with traditional flocculant PAC.So it is of obvious economic and environmental benefits.Furthermore,the flocculation mechanism of this composite flocculant is discussed.