脱硫废水浓缩滤液烟气旁路蒸发喷枪设计及系统运行优化

Design of flue gas bypass evaporation spray gun and system operation optimization for treating desulfurization concentrated wastewater

烟气旁路蒸发系统在脱硫废水零排放中的应用越来越广泛,但脱硫废水浓缩滤液含盐量高、腐蚀性强、硬度大,旁路蒸发处理过程易堵塞喷枪喷嘴。试验确定了喷枪尺寸参数,解决了滤液堵塞喷枪喷嘴的问题;根据喷枪喷射特性设计蒸发器尺寸并完成旁路蒸发系统。现场实际运行发现,高温烟气量约为理论计算的1.06~1.20倍,可通过蒸发器测温系统判断滤液雾化蒸发效果和蒸发器堵塞情况,当出现积灰时,启动振打除灰和吹灰系统。投入蒸发器系统后,除尘器入口烟温平均升高3.6℃,对除尘器除尘效率无影响。

The flue gas bypass evaporation system is more and more widely used in the zero discharge of desulfurization wastewater.However,due to the high salt content,strong corrosivity and high hardness of the concentrated filtrate of desulfurization wastewater,the nozzle of the spray gun is easy to be blocked during the bypass evaporation process.The size parameters of the spray gun were determined through experiments,which solved the problem that the filtrate blocked the nozzle of the spray gun.According to the spray characteristics of the spray gun,the evaporator size was determined and the bypass evaporation system was designed.The actual operation on site found that the amount of high-temperature flue gas is about 1.06-1.20 times of the theoretical calculation.The temperature measurement system on the evaporator can be used to judge the effect of filtrate atomization and evaporation and the blockage of the evaporator.When ash deposition occurs,start the rapping ash removal and soot blowing systems.After the evaporator system is put into operation,the flue gas temperature at the inlet of the precipitator increases by 3.6℃on average,which has no impact on the dedusting efficiency of the precipitator.