城市中水对湿法烟气脱硫工艺的影响

Influence of recycled water on wet flue gas desulfurization process

以湛江电力有限公司工业原水由地下水改为城市中水为例,分析和讨论了中水对湿法烟气脱硫工艺三方面的影响:(1)抑制吸收塔内CaCO_3的转化及CaSO_3·1/2H_2O的氧化过程;(2)导致脱硫石膏Cl^-含量和含水率升高,石膏品级降低。真空过滤不同Cl^-含量的石膏浆液,发现随着石膏浆液Cl^-含量的升高,过滤得到的石膏滤饼含水率升高,即Cl^-的存在不利于石膏浆液的脱水;(3)Cl^-含量升高加剧了脱硫系统中碳钢及不锈钢的腐蚀,特别是碳钢在高浓度Cl^-溶液中会发生剧烈全面腐蚀。

Taking Zhanjiang Electric Power Co. , Ltd. whose industrial raw water switches from groundwa- ter to recycled water as an example, analysis and discusses the influence of recycled water on wet flue gas desulfurization process ：①inhibit the transformation of CaCO3 and the oxidation of CaSO3 · 1/2H=O in the absorption tower;②lead to the increasement of CI- and water content of desulfurization gypsum. By filtra- ting different C1- content of gypsum slurry, we found that with the increasement of C1- content in gypsum slurry,the obtained gypsum filter cake has a higher water content, the presence of Cl- is not conducive to the dehydration of gypsum slurry;③C1- aggravated the corrosion of carbon steel and stainless steel in the desulfurization system, especially, severe and comprehensive corrosion will occur to carbon steel in high C1- concentration solution.