Effect of Season on NO{sub}x Emission from Commercial Waste Coal-Fired Circulating Fluidized Bed Boilers

摘要

The results of a study aimed at understanding the effect of season on ammonia usage to control NO{sub}x in circulating fluidized bed (CFB) coal-fired power plants are discussed. Historical data on fuel properties, operating conditions, and emission characteristics provided by two plants were used. The extensive data were carefully and thoroughly examined and analyzed for any evidence of seasonal trend in NO{sub}x and any of the variables.. Relatively higher ammonia was required to control NO{sub}x in winter than the rest of the year at the plant that uses it to control NO{sub}x. A predictable seasonal variation was observed for only a few parameters (humidity ratio, ammonia consumption, fuel moisture content, and ambient air temperature). Bed temperature, excess oxygen, Ca/S ratio, and ammonia consumption were suspected to be related to the variation in NO{sub}x emission.