Unreasonable distribution of ammonia injection quantity in SCR equipment of some domestic power plants caused large deviation of outlet NOx concentration

and too high escaped ammonia content at local regions.Thus

adjustment of ammonia injection quantity for SCR system on a 300 MW unit was conducted.After the optimization

NOx distribution at the outlet of the system was improved significantly

and the peak value of escaped ammonia decreased.Besides

the relative standard deviation of NOx distribution dropped from 45%(before the optimization) to 10%

and the average concentration of escaped ammonia reduced from 1.7 μL/L to 0.98 μL/L.Moreover

the maxium denitration efficiency of the SCR system increased from 80% to 88%.