水质电导率测定方法

Determination method of water conductivity

建立一种适用于地表水、地下水、海水和废水电导率的测定方法。待测水样在4℃下密封保存,并于24h内用校正过的电导率仪测定25℃时的电导率。当测定温度超出(25±0.1)℃范围时,需进行温度补偿。该方法针对不同样品,分别采用过滤法、萃取法及过滤–萃取法进行预处理,比较了干扰消除效果,结果表明过滤法适用于所有水样。对4种不同水体的水样进行测定,测定结果的相对标准偏差均小于0.6%(n=6)。验证结果表明,该方法具有较好的重复性和准确性。

A method for the conductivity determination of surface water, ground water, sea water and waste water was established. The water sample was sealed and stored at 4℃, and the conductivity of the water sample at 25℃ would be measured within 24 h by a calibrated conductivity meter. When the temperature of water sample was not at (25±0.1)℃, the test result needed to be compensated according to the temperature of measured water sample. The interference eliminating effect of filtration method, extraction method and filtration–extraction method were compared, and the filtration method was the best for all sorts of water samples. Water samples from 4 different water bodies were tested,and the relative standard deviations of the results were less than 0.6%(n=6). The verification results showed that this method had good repeatability and accuracy.