脱硫废水零排放（ZLD）已成为现阶段环境治理的趋势，传统的治理方法具有高成本、难维护等缺点，因此提出一种利用中高温烟气干燥电厂脱硫废水的新技术。通过将选择性催化还原（SCR）脱硝后的热烟气引入喷雾干燥器，雾化废水使其与烟气充分接触，经干燥进入空气预热器后的原烟道。结果表明：抽取锅炉烟气量的7%左右可干燥脱硫废水2.5 t，使锅炉热效率降低0.68%左右，影响较小。干燥后烟气酸露点温度从93.20 ℃提高到96.72 ℃，不会腐蚀空气预热器等后续工艺设备，同时该技术有利于静电除尘器（ESP）、湿法烟气脱硫（WFGD）系统的运行，利用中高温烟气干燥脱硫废水是可行且有效的技术方法。

Zero liquid discharge(ZLD)of desulfurization wastewater has become the trend of environmental management.Traditional governance methods have the disadvantages of high cost and difficulty in maintenance.This paper proposed a new technology for drying desulfurization wastewater from power plants using medium and high temperature flue gas.The flue gas after denitrification by selective catalytic reduction (SCR) was introduced into the spray dryer,and the wastewater is atomized into sufficient contact with the flue gas and dried to enter the original flue after the air preheater.The analysis results show that the desulfurization wastewater could be dried for 2.5t after extracting about 7% of the boiler flue gas,and the boiler thermal efficiency was reduced by 0.68% with less impact.The temperature of flue gas dew point after drying is increased from 93.20 ℃ to 96.72 ℃.It indicates that the subsequent process equipment such as the air preheater could not be corroded,and the technology is beneficial to the operation of the electrostatic precipitator (ESP) and wet flue gas desulfurization (WFGD) systems.Therefore,it is a feasible and effective technical method to dry desulfurization wastewater by using medium and high temperature flue gas.

X773

国家自然科学基金(61174111)