CODcr测定中氯离子的影响及消除

根据油田采出水中氯离子含量高，对COD_(Cr)测定影响较大的特点，通过实验探讨高含氯对测定污水CODCr的影响及消除其影响的方法。实验结果表明，对高含氯、低CODCr的污水用国标方法测定CODCr时会产生较大误差，且误差随氯离子含量的增加而增大；采用不掩蔽氯离子测污水CODCr总量，再用CODCr总量减去氯离子产生CODCr量的方法，则能反映污水的真实CODCr值，误差小一些。

The effect of chlorine ion in COD_(Cr) determination and the way of removing this effect

Based on the characters of high chlorine ion content in produced wa-ter of a oil field that effected CODCr determination authors discussed the effect of high cholrine content sewage upon CODCr determination and the method of removing the effect by means of experiment .The experimental result showed that the state standard method of determining CODCr in sewage of high percentage chlorine and low percentage CODCr contants might have brought considerable error,and the error increased as the chlorine ion content increased .The method of admitting total CODCr value in sewage determined by chlorine ion and total CODCr minus that produced by chlorine ion could reflect the true CODCr value in sewage with smaller error.