CCPP余热锅炉SCR烟气与氨气强化混合特性

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中图分类号：TK223 文献标志码：A

Abstract：Enhancingthemixinguniformityoffluegasandammoniaisthekeyfactorforimprovingthedenitrficationefficiency and further decreasing NO x emission in the SCR of the waste heat boiler denitrification system of the CCPP generator set.The computational fluid dynamics （CFD）calculation simulation method was adopted to study the influence laws of the layout mode of the ammonia injection grid and the static mixer on the mixing process of ammonia and NO x . The results show thatthe numberdensityofammonia nozles has agreat impacton the mixing uniformity.Through the analysisofthe variation lawof the NH3/NOx ratio distribution uniformityin the cross-section of the catalyst with the densityof the nozzle，it is obtained that the optimal density range of the nozzle arrangement is between 25 nozzles/ m2 and 44 nozzles/m² with the nozzle injectiondirectionperpendiculartothefluegasflowdirection.Thestructureof thenew X-type static mixercansimultaneously enhance the uniformity of ammonia and NOx mixing and the uniformity of velocity distribution. When the number density is set to 25 nozzles/m²，optimized structural parameters of the mixer with a height of 180-190mm and a width of 200mm were obtained with an installed distance down the nozzle between 55mm and 65mm

Keywords： flue gas deNOx ; ammonia injection grid; static mixer; CCPP；computational simulation

随着中国“双碳”战略实施，具有高效、清洁和低碳特点的燃气-蒸汽联合循环发电（CCPP）成为中国电力行业发展的重要方向，预计到2025年，中国天然气发电装机量将会超过1.5亿 kW ，占总装机容量比例达 6% [1-4]。（剩余10769字）