提高化学需氧量质控合格率的研究

Research on qualification percentage of quality control to determine COD accurately

大庆油田化工总厂废水中化学需氧量（COD）的测定采用库仑法。为了提高质控合格率，从人员素质、仪器设备、电级内液等9个方面分析寻找导致误差的主要影响因素并制定对策。同时对影响电极内液及消解的因素进行正交实验确定最佳条件。结果使库仑法质控合格率由90％提高到95％，测定38次标样全部合格。

Coulostatic method has been adopted to determine Chemical OxygenDemand (COD) in the waste water of Petrochemical Plant of Daqing Petroleum Admin-istration. Authors analyzed nine aspects, such as staff competence, instrument, equip-ment and electrode internal fluid, to discover the main effecting elements that caused er-ror to raise the qualification percentage of quality control and make countermeasure.The orthogonal test of the elements effecting electrode internal fluid and dissolution.The coulostatic method made the qualification percentage of quality control go up to95 % from 9o% and 38 times determination of samples showed that they were all quali-fied.