Selective catalytic reduction (SCR) by ammonia process has been the most extensive engineering application of denitrification technology due to its excellent comprehensive performance. The uniformity of the mixed gas flow field ratio on the lateral section of the SCR reactor is a key factor affecting denitrification efficiency. This review represents the basic principle of SCR as well as the mixing efficiency index of NH3/NOx. The methods and recent work on mainstream technology of the engineering application were reviewed,such as linear controlled injection grid,divisional controlled injection grid,and mixed element type of injection grid. The advantages and disadvantages of different methods were analyzed. Further studies on the ammonia injection and mixing involve:①The mixed element type of injection grid is preferred,the divisional controlled and linear controlled type of injection grid take second place.②Focus on the feasibility of the lower concentration of non-uniform coefficient in the design of the mixing device.③Development of high efficiency,simple and stable hybrid element structure,reducing construction and operating costs, improving operational flexibility.④Perfection of the ammonia injection effect and modern control theory of amount.%氨法选择性催化还原技术(SCR)因其优良的综合性能而成为工程应用最为广泛的烟气脱硝工艺,而反应器横截面上混合气体流场均匀性优劣是高效烟气脱硝的重要影响因素.本文简述了SCR烟气脱硝系统基本原理和 NH3/NOx混合效率指标;综述了线性控制式、分区控制式和混合型喷氨格栅等几种工程应用上主流技术及其最新研究成果,并分析了各气体流场均匀性调节技术的优缺点;最后指出氨喷射混合装置未来的发展趋势:①优先选用混合型喷氨格栅,分区控制式喷氨格栅和线性控制式喷氨格栅分别次之;②喷氨混合装置设计时重点寻求降低浓度不均匀系数的可行性;③研发简易、高能和稳定的静态混合结构,降低建设和运行成本,提高操作弹性;④完善还原剂氨喷射效应和喷氨量现代控制理论.
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