Reduction of NOx Through Staged Combustion in Combined Cycle Supplemental Boilers. Volume I. Systems Optimization Analyses.

摘要

This report discusses an investigation directed to control of emissions from supplemental-fired combined cycles with the use of staged combustion in the steam generating portion of the system. A combined cycle,as considered in this report,is the assembly of any number of gas turbines,steam generators,and steam turbines for electric power generation in which the exhaust of the gas turbines is passed through the steam generators. A supplementary-fired combined cycle employs combustion of fuel in the gas turbine exhaust to increase temperatures in the steam system. Staged combustion is achieved by the separation of the exhaust from the gas turbines into two streams prior to entering the steam generator with provisions for primary combustion of fuel in one stream with a deficiency of air. Combustion is completed in a secondary stage by mixing the unfired stream into the products of the fired stream. The use of staged combustion provides conditions favorable for the occurrence of chemical reactions that result in a reduction of mass flow of nitric oxide (NO) present in the gas turbine exhaust. Volume I is concerned with the engineering analysis of combined cycle performance and NOx reduction potential.