纸浆黑液具有很深的色泽,用指示剂以酸量法测定是有困难的。此时,滴定终点不易辨别,而且由于稀释倍数很大,因此测定结果的误差也较大。为此,有必要先将有机物质灼烧除去。但在灼烧过程中,黑液的硫酸盐和硫代硫酸盐会发生氧化还原反应。为了获得正确的总碱值必须对试样在灼烧前后的硫酸盐和硫代硫酸盐含量分别进行测定,然后加以校正。1938年Mcelihininey 等首先用电导法进行总碱的测定。最近Gaslini 等又用电导法以过量醋酸置换测 Pulp black liquor has a deep color, with the indicator to determine the acid is difficult. In this case, the titration end point is not easy to distinguish, and because the dilution factor is large, the error of the measurement result is also large. To this end, it is necessary to first remove the organic matter burning. But in the burning process, black liquor sulfate and thiosulfate oxidation and reduction reaction occurs. In order to obtain the correct total base number, the contents of sulphate and thiosulphate in the sample before and after burning must be determined and then corrected. In 1938, Mcelihininey et al. First used the conductivity method to determine total alkalinity. Gaslini and so on again with the conductivity method with excess acetic acid displacement test