Optimization of flow and ammonia injection by numerical simulation of SCR for a 660 MW coal-fired unit
Li Zhuangyang
Su Lechun
Song Zijian
Tan Peng
Zhou Xu
Zhang Cheng
Sun Lushi
Chen Gang
Abstract：Selective catalytic reduction (SCR) is the most widely used denitration technology.A numerical study was carried out to evaluate the uniformity of gas flow and ammonia injection in the SCR denitration system of a 660 MW coal-fired unit.The influence of arrangement and structure of deflector on flow field in the system was investigated through comparing the uniformity of flue gas velocity and NH3 concentration distribution in the top catalyst layer.The optimized ammonia injection mode was also studied based on the numerical simulation.Results show that the optimization of arrangement and structure of deflectors significantly improved the uniformity of flue field and NH3 concentration distribution.The distribution of NH3 concentration in the top catalyst layer was further optimized by the partitional ammonia injection mode,which produced through the simulation results.And the site tests verify that the outlet NOx concentration of the SCR system was reduced by the control of the valve of ammonia injection grid.This paper aims to provide an optimized method of deflector and ammonia injection mode for the SCR system of power plant.
Keywords：Coal-fired power plantSCRNumerical SimulationOptimization of ammonia injection
Publication Date：2017-01-01