Hebei Datang International Tangshan Thermal Power Co., Ltd.. No. 2 unit denitrification urea pyrolysis system energy-saving transformation project
The project is a 1025 t/h sub-critical, natural cycle, an intermediate reheated steam furnace, a single furnace balanced ventilation, and a four-corner circular combustion method. The fuel is designed as bituminous coal. The project adopts a set of “parallel” energy-saving high-temperature flue gas bypass flue urea pyrolysis ammonia production equipment based on the existing set of conventional urea pyrolysis unit outside the furnace. The performance index of the device is designed according to the entrance NOx concentration of about 400 mg/m3, the NOx emission concentration of 50 mg/Nm3, the denitrification efficiency ≥ 87.5 %, and The temperature of bypass flue system must meet the required temperature of urea pyrolysis in the boiler condition of 50% to 100%.
The project was put into operation in December 2016. During the entire trial operation, all bypass flue systems were put into automatic operation, and the trial operation was stable and reliable. The high temperature bypass flue can increase the flue temperature of denitrification main flue 13℃, which can meet the low load of the boiler(30 % BMCR) and put it into the denitrification system; At the same time, the operation power consumption of the urea pyrolysis system is reduced by more than 400kW•h.