某电厂废水零排放旁路烟道蒸发系统对锅炉热效率影响分析

Analysis of the Influence of Zero Discharge Bypass Flue Evaporation System on Boiler Thermal Efficiency in a Power Plant

某电厂脱硫废水深度处理改造零排放系统主要处理厂区脱硫废水出水,脱硫废水深度处理零排放改造系统主工艺路线为:旁路烟道蒸发,取烟气点为SCR后、空预器前烟道,分别从AB侧烟道抽取,出口分别连接回AB侧烟道,两台机组脱硫废水深度处理改造总处理量2×10m^(3)/h(额定出力)。1号机组废水零排放旁路烟道蒸发系统于2021年5月建成,该系统投运后,在1000MW、750MW、500MW三个负荷工况下,锅炉热效率降低值分别为0.10%、0.11%、0.08%,均满足小于0.17%的性能保证值要求,达到废水零排放环保要求。

The zero discharge system for the deep treatment and renovation of desulfurization wastewater in a certain power plant mainly treats the effluent of desulfurization wastewater in the factory area.The main process route of the zero discharge renovation system for desulfurization wastewater deep treatment is:bypass flue gas evaporation,with the flue gas points taken as the flue gas after SCR and in front of the air preheater,respectively extracted from the AB side flue,and the outlets connected back to the AB side flue.The total treatment capacity of the two units for desulfurization wastewater deep treatment and renovation is 2×10 m^(3)/h(rated output).The zero discharge bypass flue evaporation system for Unit 1 wastewater was completed in May 2021.After the system was put into operation,the boiler thermal efficiency decreased by 0.10%,0.11%,and 0.08%under three load conditions of 1000MW,750MW,and 500MW,respectively,meeting the performance guarantee value requirement of less than 0.17%and meeting the environmental protection requirements for zero discharge of wastewater.