水中常见离子对解毒铬渣除磷的影响

EFFECT OF SEVERAL COMMONIONS ON PHOSPHATE REMOVALBY DETOXIFICATION CHROMIUM SLAG

研究了几种常见离子(NO3-、SO42-、HCO3-、SiO32-、Ca2+和Mg2+)对2种解毒铬渣(600℃和800℃热解解毒)除磷效果的影响。结果表明,与纯水比较,NO3(-NaNO3)和SO42(-Na2SO4)的存在能提高解毒铬渣的磷去除率;HCO3-(NaHCO3)和SiO32(-Na2SiO3)会与水中的PO43-竞争Ca2+生成沉淀,从而对铬渣除磷起抑制作用;Ca2+和Mg2+的存在能够提高铬渣的除磷率。根据上述结果及水、污水中一般离子含量,初步分析认为对铬渣固磷影响最大的应该是Ca2+、Mg2+和HCO3(-CO32-)离子,前2者起促进作用,后者起抑制作用。

The effect of several common ions （NO3^-、SO4^2-、HCO3^-、SiO3^2-、Ca^2＋,Mg^2＋） on phosphate removal from aqueous solution by detoxification chromium slag were investigated. The results showed that, compared with pure water, presence of NO3^- （NaNO3） and SO4^2- （Na2SO4） increased the phosphate removal, while HCO3^- （NaHCO3） and SiO3^2- （Na2SiO3） may generate precipitation with Ca^2＋, so that remarkably inhibited phosphate retention. Presence of Ca^2＋ and Mg^2＋ caused an increase of phosphate removal.＂ Based on the obtained results and the typical concentrations of the ions in water/wastewater, it is deemed that Ca^2＋, Mg^2＋ and HCO3^-/CO3^2- would have the greatest influence on phosphate uptake, with the former having positive while the latter having negative effect.