针对目前我国火力发电厂SCR脱硝系统烟气流场和氨气浓度场不均,对某1000MW机组SCR脱硝系统进行优化,将原直角转弯烟道调整为钝角转弯烟道,并对导流板进行优化布置,减小烟气转弯角度,降低速度不均,同时将氨气喷嘴布置方式由平行于烟气方向的单喷嘴结构调整为偏斜的双喷嘴结构,增强氨气的横向扰动,提高氨气与烟气的混合效率.对优化前后的运行情况进行仿真比较,新方案显著提高了氨气与烟气混合效率,有效改善了脱硝系统中烟气速度场和氨气浓度场的分布,同时降低了压力损失和厂用电率.%Aiming at the uneven flow field and ammonia concentration field of SCR system,We optimized the SCR system in a 1000 WM unit,adjusted the original right angled flue to obtuse angled flue and optimized the layout of guide plate,thus it can reduce the angle of turn and the unevenness of speed.Apart from that,we replaced changed the single injector which was parallel to the flow direction of flue gas with the double injector which was deflective to the flow direction of flue gas,and enhanced the lateral disturbance of ammonia,so that it can improve the mixing efficiency of ammonia and flue gas.Compare the simulation results of before and after optimization,the new project can significantly improve the mixing efficiency of ammonia and flue gas as well,and can also improve the distribution of velocity and concentration.Meanwhile it can reduce the pressure loss of the structure and power consumption rate.
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