摘要
以较常见的预氯化为技术手段,考察了预氯化工艺去除饮用水中氰化物、硫化物以及水合肼等还原性污染物的效果和影响因素。结果表明:(1)实验条件下氰化物浓度随有效氯投加量的增加而下降,并在有效氯投加量>5.0mg/L时降低到低于《生活饮用水卫生标准》(GB 5749—2006)中限值(0.05mg/L),在有效氯投加量>6.0mg/L(此时有效氯与氰化物质量比大于7.3∶1.0)时低于检测线,有效氯与氰化物质量比的实验结果与理论值(6.8∶1.0)基本一致;硫化物浓度下降幅度与有效氯投加量的平方基本呈直线关系;水合肼与氯的反应基本符合直线关系,有效氯与水合肼反应的质量比约为1∶3,与理论值(0.35)基本一致。(2)3种污染物与氯的反应速率很快。在有效氯投加量为3.0mg/L时,2min内氰化物浓度基本达到稳定;硫化物与氯的反应在30s内即可完成;水合肼和氯的反应在2～3min内完成。(3)在pH约为8的条件下,硫化物溶液浓度较为稳定,基本不受pH的影响;氰化物溶液稳定性较差,浓度易发生变化。pH对氰化物、硫化物、水合肼和氯反应过程的影响同样不显著。
The pre-chlorination technology was applied for removal of reductive compounds such as cyanide compounds,sulfide and hydrazine hydrate in drinking source water.The performance and influence factors of pre-chlorination technology were studied through the simulating tests.Results showed that the concentration of cyanide was decreased with increasing the active chlorine dosage,when active chlorine5.0 mg/L,the residue cyanide lower the standard value（0.05 mg/L） and when active chlorine6.0 mg/L,residue cyanide could be undetected,then the mass ratio of active chlorine to cyanide was 7.3∶1.0,which accordance with the theoretical value（6.8∶1.0）.The descent of sulfide was liner correlated with the square of active chlorine dosage.The mass ratio of active chlorine to hydrazine hydrate was 1∶3 in pre-chlorination,which accordance with the theoretical value（0.35）.Chlorine could remove these reductive pollutions quickly and efficiently,when active chlorine was 3.0 mg/L,cyanide compounds,sulfide and hydrazine hydrate could be totally removed in 3 min.The sulfide solution was stable when pH at 8,while the cyanide solution was instable,so the concentration of cyanide was easily to change.The effect of pH on pre-chlorination was not significant.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2011年第11期10-14,共5页
Environmental Pollution & Control
基金
国家水体污染控制与治理科技重大专项"饮用水水质监控预警及应急技术研究与示范"(No.2008ZX07420-005)
国家水体污染控制与治理科技重大专项"典型城市饮用水安全保障共性技术研究与示范"(No.2009ZX07424-003)
关键词
氰化物
硫化物
水合肼
预氯化
应急处理技术
cyanide compounds
sulfide
hydrazine hydrate
pre-chlorination
emergent water-treating technology
