Abstract: Taking the 2×660MW ultra supercritical unit reconstruction project of a power plant as example, the general situation of the ammonia injection grid of the SCR deNOx project, which contains square tooth type rub preventing mixing plate and has low resistance, was introduced. The features and idea of the optimized design of the ammonia injection grid were expounded. The test verification and the application result in practical project show that the ammonia injection grid can satisfy the requirements of ammonia injection and mixing in deNOx projects.

Key words: selective catalytic reduction method, nitric oxide, flue gas deNOx, ammonia injection grid