Received Date:2023-01-05 Revised Date:2023-01-31 Publish Date:2023-03-05
Download
2023 NO.01
Setting up an economizer flue gas bypass system is an effective approach to increase the inlet flue gas temperature of the denitration system in a coal-fired power plant and maintain high De-NO_x efficiency under all working conditions. In order to analyze the economy of the denitration system in a coal-fired power plant during frequent load cycling processes, the dynamic models of a 660 MW ultrasupercritical coal-fired power plant and the SCR system are developed. Then, the cost of urea, the environmental cost of NO_x emission and the cost of coal are obtained and compared under different flue gas bypass baffle opening during the loading up processes from 50%THA to 100%THA. The results show that the change value of coal cost is the largest, and the total cost has a certain increase when the economizer flue gas bypass baffle is opened during the load cycling processes. When the flue gas bypass baffle opening is 5% and 10%, the cost of coal increases by ¥600 and ¥1200 respectively during the loading up processes from 50% to 75%THA. Meanwhile, the cost of urea decreased by ¥442.48 and ¥554.89 respectively, while the environmental cost of NO_x emission changed less, only ¥62.22 and¥63.19. Moreover, the cost of coal increased by ¥1800 and ¥2300 respectively during the loading up processes from 75% to 100%THA, and the amounts of change in urea cost and NO_x emission environmental cost were little. Therefore, it is not recommended for coal-fired power plant to open the flue gas baffle during the loading up processes from 75% to 100%THA.
Close-GAO Wei, LIU Ming, ZHAO Yongliang, et al. Economic analysis of denitration system in a coal-fired power plant with flue gas bypass during load cycling processes[J]. Energy Environmental Protection, 2023, 37(1): 13-20.