采用电量法测定碱液中的Cl^(-)含量

Determination of chloride ion content in alkaline solution using the electric quantity method

烟气脱硫装置需要测定烟气脱硫系统的碱液、脱硫塔循环液、滤清水样品中Cl^(-),但现有标准在检测范围和适用性上不能满足生产需求。为了使分析检测更加准确,对生产实际起到指导作用,采用电量法建立了适合某公司烟气脱硫装置碱液中Cl^(-)浓度的分析方法,用标样和样品加标回收法进行了回收率验证,回收率在100%±5%范围内,准确度高,可检测Cl^(-)浓度范围为10~1000 mg/L内的碱液。通过对烟气脱硫装置碱液等测量结果进行重复性验证,满足95%概率水平要求,制定了测量结果在10~400 mg/L范围内的重复性限值,为测量未知样品的Cl^(-)含量提供参考。

The flue gas desulfurization(FGD)unit requires measuring the Cl^(-)concentrations in the alkaline solution,circulating fluid of the desulfurization tower,and filtered water samples in the FGD system.However,existing standards cannot meet production needs in terms of detection range and applicability.To improve the accuracy of analysis and testing and provide guidance for practical production,an analytical method suitable for measuring Cl^(-)concentrations in the alkaline solution of a certain company's FGD unit has been established using the coulometric method.Verification of the recovery rate was conducted using standard samples and sample spiking methods,resulting in a recovery rate within the range of 100%±5%,indicating high accuracy.This method can detect Cl^(-)concentrations in alkaline solutions ranging from 10 to 1000 mg/L.Through repetitive verification of measurement results of the alkaline solution and other samples from the FGD unit,the requirements for a 95%probability level were met.Repeatability limits were set for results ranging from 10 to 400 mg/L,providing a reference for measuring the Cl^(-)content of unknown samples.