600 MW火电机组湿法脱硫旁路挡板封堵改造案例

按照国家“十二五”节能减排政策要求,某电厂600 MW机组湿法脱硫系统于2012年5月17日封堵了烟气旁路挡板门。对比湿法脱硫旁路挡板门封堵前后的技术特点,指出取消旁路对机组和脱硫系统安全运行的不利影响。为提高脱硫系统运行可靠性,该电厂将脱硫设备纳入主设备予以管理,在烟气旁路挡板门封堵后采取了一系列针对性措施：设置烟气事故喷淋系统,增设除雾器冲洗水管路,增加1条供浆管道,大容量设备分段供电,调整逻辑保护,必要时投加添加剂稳定脱硫效率等。烟气旁路挡板门封堵后运行半年来,该电厂脱硫设备运行稳定,未出现因脱硫设施故障导致主机停运等事故。

Case Study on Reconstruction of Wet FGD Bypass Damper Plugging for 600-MW Thermal Units

According to the requirements of energy saving and emission reduction policy for the 12^th Five-Year period, the bypass damper for the wet FGD system of a 600-MW unit in one power plant was plugged on May 17, 2012. Based on the comparison between the technical characteristics before and after plugging, the adverse effects of eliminating the bypass on the secure operation of the unit and the desulfurization equipment are presented. To improve the reliability of the desulfurization system, the desulfurization equipment is incorporated into the main equipment management with a series of measures adopted, such as installing a flue gas emergency spraying system, adding water pipelines to the mist eliminator, building a pipeline for slurry supply, splitting the power bus for large devices, adjusting logical protection and using additives for stable desulfurization efficiency. Since then, the desulfurization equipment runs stably, and no main equipment shutdown has ever happened due to breakdown of the desulphurization facilities.