What are the commonly used reducing agents for SNCR denitration in circulating fluidized bed coal-fired boilers?

There are three main reducing agents in the denitration system: liquid ammonia, ammonia water and urea. The choice of the reducing agent is one of the main factors affecting the denitration efficiency and operating economy.Most of the power plants use urea, and a small part is ammonia water. Some chemical plants or power plants with rich management experience use liquid ammonia.At present, for some small industrial circulating fluidized bed boilers for steam supply and heating, when designing the system of the Design Institute, the storage safety of ammonia water is relatively strict, and most of the reducing agents use urea.