Optimization Of COD Determination Method In Oil Field Monitoring

Chemical oxygen demand is an important index to characterize the degree of water pollution,but because of the different conditions of water quality,the difference between methods for the determination of large,according to the water quality monitoring of oil and gas fields,based on comprehensive analysis of domestic and international chemical oxygen demand method,this paper carried out the optimization of determination of COD in water quality monitoring in oil and gas fields,and data statistics the analysis method is verified.The analysis of the "Determination of the chemical oxygen demand in water by potassium dichromate method(HJ828-2017),"High chlorine wastewater COD Determination of chlorine correction"(HJ/T 70-2001),COD online monitoring technology,"Determination of the chemical oxygen demand fast digestion spectrophotometric method points"(HJ399-2007),statistics the main methods of standard sample detection,recovery experiments,method detection limit,uncertainty evaluation.Through the survey found that the chemical oxygen demand in water quality monitoring problems such as high level waste chlorine The accuracy and precision of the standard and improvement of experiment.The results showed that,in the oil field water quality monitoring in the standard method for detecting chemical oxygen demand needs to be improved,in order to reduce the experimental error,improve the monitoring efficiency.One is the absorption device improved reflux.Export glass tube in the experimental device is changed into a glass sand core the delivery tube,the gas bubbles are uniform,is favorable to the production of chlorine are better absorption;two is the connection between the flask and cannula flow device design and installation of a silicone tube between two glass tubes.After each sample will be connected to the silica gel pipe under intubation flask,dry cleaning is improved;three the experimental method,measured in the steps of increasing chlorine blank correction value,with the formula COD(mg/L)= COD the apparent chloride correction value-chlorine blank correction value;four is to increase the flow meter A series system is used to improve the efficiency of monitoring and analysis of high chlorine wastewater;five is to revise and validate the chlorine correction method based on HJ828-2017.