北京市某区浅层自备井水总硬度的影响因素分析

Influencing Factors for Total Hardness of Homemade Wells Water in a District of Beijing

目的了解北京某区浅层自备水井中总硬度含量的影响因素。方法选取北京某区5眼浅层自备井和1眼深层自来水厂水源井。分别于2004—2010年枯水期(4、5月)和丰水期(8、9月),在井口泵房采集井水水样,检测总硬度、pH值、氯化物、硫酸盐。结果共采集自备井水样70件,总硬度合格36件,合格率仅为51.43%。不同年度间自备井水中总硬度含量间比较,差异无统计学意义。相关性分析结果显示,自备井水中总硬度与pH值呈负相关(r=-0.919,P<0.05),与硫酸盐、氯化物呈正相关(硫酸盐r:=0.846,P<0.05;氯化物r:=0.843,P<0.05)。与自备井比较,自来水厂水源井水样中总硬度、硫酸盐、氯化物含量均较低,pH值较高,差异均有统计学意义(P<0.01)。与枯水期比较,丰水期自备井水样中总硬度、硫酸盐、氯化物含量均较高,差异均有统计学意义(P<0.05或P<0.01)。结论该区浅层自备井水总硬度的主要来源是大气降水将地表盐类污染物的带入。

Objective To know the influencing factors for total hardness of homemade wells water in a district of Beijing. Methods Five shallow homemade wells and one deep public well were chosen and sampled at pumping station for investigation according the Hygienic Standard for Drinking Water （2006）.The total hardness, chloNde, sulfate ,etc. were determined at dry season （April or May）,wet season （August or September） during 2004-2010. Results Among 70 water samples, the total hardness of 34 water samples was over the standard limits. The differences among years were not statistically significant. The correlation among total hardness,pH,chloride and sulfate was observed. Total hardness was positively correlated to the concentrations of sulfate （r=0.846,P〈0.05） and chloride（r=0.843,P〈0.05）,was negatively correlated to the pH value（r=-0.919, P〈0.05）. Total hardness, concentrations of sulfate and chloride in shallow homemade well water were significantly higher than those of deep public well, and pH value in shallow well water was lower, the differences were statistically significant（P〈0.01）. Total hardness, the concentrations of sulfate and chloride in homemade wells at wet season were significantly higher than those at dry season（P〈0.05, P〈0.01）. Conclusion Total hardness of homemade wells water in the investigated district is mainly from the salts pollution of ground through rain wash.