烟气蒸发结晶技术在脱硫废水零排中的应用

Flue gas evaporation crystallization technology in the application of the desulphurization wastewater zero discharge

为降低石灰石-石膏湿法脱硫废水零排放运行成本、减少蒸汽消耗,根据高温未饱和原烟气的特性,从石灰石-石膏湿法脱硫的原烟气中引出一部分烟气,进入废水蒸发结晶塔,浓缩脱硫废水,使废水中可溶性盐浓缩、结晶,再经中和、沉降、分离出盐,滤液返回蒸发结晶系统,继续循环蒸发。盐主要成分为氯化钙、硫酸钙。经核算该工艺与现有"混凝沉淀预处理+蒸发结晶处理"工艺相比,无需预处理药剂、工艺水、蒸汽,没有特殊的设备,废水可在脱硫内部的循环利用,还具有投资省及运行成本低的特点。

In order to reduce the limestone-gypsum wet desulphurization wastewater zero discharge operation cost , reduce steam consumption , according to the characteristics of high temperature unsaturated rawgas,a part of the flue gas from flue gas limestone gypsum wet desulphurization in the wastewater into the evaporation crystallization tower,concentrated desulphurization wastewater,thesoluble salt in the wastewater concentration,neutralization and crystallization settlement and separation of salt , the filtrate returned tothe evaporation and crystallization , continue circulating evaporation. The main components of phate. After the accounting process and the existing ＂ coagulation pretreatment ＋ evaporacompared without pretreatment agent,process water,steam,no special equipment , recycling wastewater in desulphurization,also has the characteristics of investment and low operating cost.