Research and Renovation of Urea Pyrolysis Process System in a Power Plant
Aiming at the problems of high energy consumption,high failure rate,and unstable operation of the denitrification system in the urea pyrolysis system of a power plant's original electric heater,a renovation plan was proposed to replace the electric heater with a furnace gas-gas heat exchanger.The gas-gas heat exchanger inside the furnace is arranged above the horizontal section of the low-temperature reheater of the coal-fired unit,and the material of the heat exchange tube is 06Cr25Ni20.The gas-gas heat exchanger inside the furnace leads to an increase of about 2.7%in coal consumption,a decrease in flue gas temperature below 5℃,and a decrease of 0.03%in boiler efficiency.The impact on boiler efficiency can be ignored.Through economic analysis,the renovated power plant saves an annual cost of 1.267 2×106 yuan,which has significant economic benefits.
power plantcoal-fired uniturea pyrolysisfurnace gas-gas heat exchanger