摘要
针对新疆新港作业公司采出水软化器外排含盐废水COD(Chemical Oxygen Demand,COD)波动大、测不准及异常高的问题,首先对软化器外排含盐废水进行了水质分析,并对现场生产部门提供的COD监测数据进行了分析,发现外排含盐废水Cl^-浓度高达128904.46mg/L,属典型的高氯废水,初步确定生产现场COD浓度测定值异常的主要原因是外排含盐废水中Cl^-干扰引起。然后开展了Cl^-对废水COD准确测定的干扰及减轻干扰方法研究,结果表明,常规重铬酸盐法测定高氯废水COD时,因为Cl^-的干扰会产生很大误差;采用硫酸汞掩蔽法(HgSO_4与Cl^-质量比=10∶1)与低浓度重铬酸钾法(重铬酸钾浓度为0.025mol/L,硫酸亚铁铵浓度为0.01mol/L)结合测定模拟含盐废水COD,测定结果满足国家标准对COD测定误差的要求,采用该法测出软化器外排含盐废水COD浓度为386.1mg/L,测定了模拟含盐废水及软化器外排含盐废水的TOC,表明COD测定结果具有一定准确性和可靠性。采用硫酸汞掩蔽法与低浓度重铬酸钾法仍属于国家标准GB11914-89(重铬酸盐法)的范围,只是其延伸,建议该油田及油田所在地环保部门采用这种方法监测外排含盐废水COD。
According to the problem of discharged wastewater COD(Chemical Oxygen Demand)from the softener with volatility,uncertainty and abnormal high COD in Xingang Oil Production Company in Xinjiang,the water quality of salinity wastewater from the softener is measured and analyzed,and the Cl-concentration is as high as 128904.46mg/L in the discharged wastewater,it is a typical high chloride wastewater,and monitored COD data on site are analyzed.It is preliminarily determined that the main cause of abnormal COD is caused by Cl-interference in discharged salinity wastewater.The interference of Cl-on COD is accurately detected and to mitigate the interference caused by Cl-in wastewater.The results show that the determination of the high chlorine wastewater COD has a high error because of the interference of Cl-as conventional potassium dichromate method is used,and the COD determination results can meet the requirement of the national standard for the measurement error of COD combined with the mercury sulfate masking method(HgSO_4 and Cl-mass ratio is 10∶1),a low concentration potassium dichromate(CK_2Cr_2O_7=0.025mol/L,C(NH_4)_2Fe(SO_4)_2=0.01mol/L)is used to determine the simulated wastewater containing salt COD,and the softener efflux salt wastewater COD is 386.1mg/L by using the measuring method,and the TOC is measured in the simulated wastewater containing salt and discharged salinity wastewater from the softener,it shows that COD determination results has certain accuracy and reliability.The mercury sulfate masking method and low concentration of potassium dichromate method still belong to the scope of national standard method(GB11914-89,potassium dichromate method),it is its extension,it is recommended that the oilfield and the local environmental protection department use the method to monitor COD in the discharged salinity wastewater.
出处
《长江大学学报（自科版）（上旬）》
2016年第6期1-6,共6页
JOURNAL OF YANGTZE UNIVERSITY (NATURAL SCIENCE EDITION) SCI ＆ ENG
基金
中国石油集团安全环保技术研究院科研课题
关键词
含盐废水
COD测定
重铬酸盐法
准确性与可靠性
salinity wastewater
COD determination
potassium dichromate method
accuracy and reliability
