水中常见离子对解毒铬渣除磷的影响

研究了几种常见离子(NO_3~-、SO_2~(4-)、HCO_3~-、SiO_3~(2-)、Ca~(2+)和Mg~(2+))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,NO_3~-(NaNO_3)和SO_4~(2-)(Na_2SO_4)的存在能提高解毒铬渣的磷去除率;HCO_3~-(NaHCO_3)和SiO_3~(2-)(Na_2SiO_3)会与水中的PO_4~(3-)竞争Ca~(2+)生成沉淀,从而对铬渣除磷起抑制作用;Ca~(2+)和Mg~(2+)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Ca~(2+)、Mg~(2+)和HCO_3~-(CO_3~(2-))离子,前2者起促进作用,后者起抑制作用.

EFFECT OF SEVERAL COMMONIONS ON PHOSPHATE REMOVAL BY DETOXIFICATION CHROMIUM SLAG

The effect of several common ions (NO_3~-, SO_4(2-), HCO_3~-, SiO_3~(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 NO_3~- (NaNO_3)and SO_4~(2-) (Na_2SO_4) increased the phosphate removal, while HCO~3~-(NaHCO_3) and SiO_3~(2-)(Na~SiO~3)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 HCO_3~-/CO_3~(2-) would have the greatest influence on phosphate uptake, with the former having positive while the latter having negative effect.