The SCR denitration system in a 660 MW coal-fired thermal power unit has several problems

like low denitrification efficiency

high ammonia consumption and over large ammonia escape rate.To solve this problem

aphysical fluid model for this SCR device was built with proportional scale of 1∶12

and the cold state test of flow field and concentration field were carried out.Moreover

by computational fluid dynamics software STAR-CCM+

numerical simulation was performed

and the structural parameters affecting the SCR denitration performance and the ammonia spray amount at each ammonia injector were optimized.The results show that

the numerical simulation results are in accordance with the cold state test results.The denitrification efficiency of the optimized SCR device was increased effectively.The ammonia escape rate was reduced to lower than 3mg/m3.The study can provide a reference for performance optimization and transformation for similar SCR systems.