Research on the Analysis Methods of Surface Water with High Chlorine and Low Chemical Oxygen Demand
The chloride ion content in the water quality of some river sections in Dingbian County is generally from 2 000 mg/L to 4 000 mg/L,and the river(lake)bed and both banks are severely salinized.Chloride ions are main interfering substances in the determination of chemical oxygen demand,and the interference of chloride ions on COD determination results can be eliminated by the complexation of different concentrations of mercury sul-fate.When C(Cl-)≤2 500 mg/L and using a 10 mg/L mercury sulfate solution,the interference of chloride ions on COD results is very small,when 2 500 mg/L≤C(Cl-)≤3 500 mg/L and using a 15 mg/L mercury sulfate solution,the interference of chloride ions on COD results is small,and when 3 500 mg/L≤C(Cl-)≤4 000 mg/L and using a 20 mg/L mercury sulfate solution,the interference of chloride ions on COD results is small.
High chlorineLow chemical oxygen demandSurface waterChloridion(Cl-)
NETL
NSTL
万方数据
