Abstract:

In order to improve the performance of denitration, reduce ammonia escape rate, reduce the risk of air preheater blockage and meet the environmental requirements of low emission standards, the optimization experiments on ammonia spraying for SCR denitrification system of  a 2×330MW coalfired power plant are studied.The distribution deviations of NOx concentration at the SCR denitrification system outlets of  #1 and  #2 units decreased 29.6% and 45.2% respectively after the optimization. The mass concentrations of ammonia slip were declined by 0.418mg/m3 and 1.786mg/m3 on average. The amounts of ammonia by the SCR device were regulated by adjusting the opening of ammonia injection valve, which improves the distribution uniformity of NOx mass concentration at the outlet of SCR denitrification system significantly, eliminates the peak of localized peak of ammonia slip and reducing the ammonia slip rate.

Key words:

SCR denitrification system, spraying ammonia optimization, NOx mass concentration, mass concentration of ammonia slip, valve opening