SCR脱硝系统喷氨格栅的模拟优化

Simulation and Optimization of Ammonia Injection Grid of SCR Denitration System

以锅炉的选择性催化还原(Selective Catalytic Reduction,SCR)脱硝系统为研究对象,运用数值模拟的方法分析原喷氨格栅结构下烟气与氨气的混合效果,对其结构和布置形式进行优化调整,发现缩小喷氨圆管上喷氨孔的直径并采用两侧布置大孔径中间布置小孔径的形式,可增强氨气射流的穿透力,NH3摩尔浓度的变异系数Cv最高下降20%,烟气与氨气混合均匀性得到大幅提升。

Taking the boiler selective catalytic reduction(SCR)denitration system as the research object,the numerical simulation method was used to study and analyze the mixing effect of flue gas and ammonia under the original ammonia injection grid structure.The structure and layout were optimized and adjusted.It was found that reducing the diameter of the ammonia injection hole on the ammonia injection round tube and adopting the structure of large apertures on both sides and small apertures in the middle can enhance the penetration of the ammonia jet.The coefficient of variation Cv of the molar concentration of NH3 decrease by maximum 20%.The mixing uniformity of flue gas and ammonia gas is greatly improved.