The wastewater zero liquid discharge (ZLD) system for the treatment of desulfurization wastewater produced from a 2 × 350 MW generator set in Henan Jiaozuo was optimized and improved by introducing the bypass flue evaporation system.The high-temperature flue gas with 330 ～ 350 ℃ was introduced from the gas duct between SCR and air pre-heater.The bypass flue evaporation system was segregated from the main gas duct by electric isolation damper.Further the electric damper at the entrance was arranged to adjust the gas flow rate and velocity.The droplets was atomized by the two-fluid atomization nozzle,and then transferred heat with high temperature to implement its efficient evaporation.The outlet of the bypass flue evaporation system was arranged on the passage between air pre-heater and dust collector,and the crystal was captured by the dust collector while the steam was condensed in FGD.The bypass flue evaporation system had little effect on the generator set and realized the zero discharge of desulfurization wastewater at last.%在河南焦作某电厂2×350 MW机组脱硫废水烟气余热蒸发零排放工程的运行基础上,进行工艺的优化与改进,创造性地引入旁路烟道蒸发系统:在SCR脱硝装置后、空气预热器前引出少量高温烟气(烟温在330 ～350℃)至旁路烟道系统;旁路烟道出、入口通过电动隔离挡板实现与主体烟道的隔离;旁路烟道入口加设电动调节挡板以调节烟气的流量、流速;旁路烟道内设置高效双流体雾化喷嘴,雾化液滴与引入的高温烟气进行迅速传质、传热,实现液滴的高效蒸发;旁路烟道出口连接在空气预热器后、除尘器前的烟道上,蒸发后的结晶物随烟气在除尘系统得到去除,水蒸气在脱硫塔被冷凝后间接补充脱硫工艺用水,最终实现了脱硫废水零排放,且对电厂原有系统影响较小.
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