高氯低有机物废水COD_(Cr)测定方法的标准研究  

Determination method standard of COD_(Cr) in wastewater with high chlorine and low organic matter

作　　者：程龙军 彭娟 杨柳荫 安晓英 CHENG Longjun;PENG Juan;YANG Liuyin;AN Xiaoying(Shenzhen Environmental Technology Group Co.,Ltd.,Shenzhen 518049,China;3R Environmental Technology INC.,Huizhou 516267,China;CenerTech Tianjin Chemical Research and Design Institute Co.,Ltd.,Tianjin 300131,China)

机构地区：[1]深圳市环保科技集团有限公司,广东深圳518049 [2]斯瑞尔环境科技股份有限公司,广东惠州516267 [3]中海油天津化工研究设计院有限公司,天津300131

出　　处：《工业水处理》2021年第10期129-132,共4页Industrial Water Treatment

基　　金：打造深圳标准专项资金资助项目(2018FQZZ0122,zxzj20191113000096)。

摘　　要：采用重铬酸钾法测定废水中的COD_(Cr),其中的氯离子也会被重铬酸钾氧化,从而使测定结果产生正误差,氯离子含量越高误差越大。在现有标准分析方法(重铬酸钾法)的基础上进行改进,通过增加掩蔽剂的方式掩蔽高浓度的氯离子,采用快速密闭消解法测定高氯废水中的COD_(Cr)。采用改进方法测定COD_(Cr)标样(含氯离子质量分数8%),RSD分别为6.58%(n=10)、5.47%(n=8)和5.02%(n=8);采用改进方法测定废水样品(含氯离子质量分数7.76%)和加标样,平均加标回收率为93.9%。经验证,改进方法对于高氯低有机物废水中COD_(Cr)的测定具有良好的精密度和准确度,据此建立了氯离子质量分数不高于8%的高氯低COD_(Cr)废水COD_(Cr)的标准测定方法,方法COD_(Cr)检出限为6.3 mg/L,定量下限25 mg/L。该研究为高氯低COD_(Cr)废水无害化处理提供了快速可靠的COD_(Cr)测定方法。There were positive errors because of chloride ions being also oxidized by potassium dichromate while potassium dichromate method was used to determine the COD_(Cr)of wastewater,and the errors were greater while the chloride ions content was higher.The existing standard analytical method(potassium dichromate method)was improved.The high concentration of chloride ion was masked by adding masking agent,and the COD_(Cr)of wastewater containing high chloride was determined by fast closed digestion method.The improved method was used to determine COD_(Cr)standard sample(containing 8%chloride),and RSD were 6.58%(n=10),5.47%(n=8)and 5.02%(n=8).The improved method was used to determine the wastewater samples(containing 7.76%chlorine)and the added standard samples,the average addition recovery rate was 93.9%.It was proved that the improved method had good precision and accuracy in the determination of COD_(Cr)in high chlorine and low organic matter wastewater.A method for COD_(Cr)determination of high chlorine wastewater with chloride ion content of no more than 8%was established.The method detection limit was 6.3 mg/L,the quantitative lower limit was 25 mg/L.The problem of COD_(Cr)determination of high chlorine wastewater was solved,and a fast and reliable COD_(Cr)determination method was provided for the harmless treatment of wastewater with high chlorine and low COD_(Cr).

关 键 词：COD_(Cr) 高氯低有机物废水 重铬酸钾法 快速密闭消解法 

分 类 号：X832[环境科学与工程—环境工程]