Laboratory Studies and Mathematical Modeling of NOx Formation in Combustion Processes.

摘要

Laboratory studies were conducted to investigate the basic factors affecting nitrogen oxide formation in the combustion of fossil fuels. A jet-stirred combustor and a multiburner (so-named because of its ability to burn gas,oil or pulverized coal fuels) were used. The jet stirred combustor was used to study NO(x) formation in combustion under kinetically limited conditions. The combustion conditions were selected to be pertinent to stationary sources such as furnaces and boilers with peak temperatures ranging from 2500-3500 F. Preliminary experiments were performed with the multiburner which indicated the influence of heat losses and residence time on NO(x) emissions in the combustion of methane/air. The multiburner was used as a rudimentary flow reactor to study the formation of nitrogen oxides in air at high temperatures. The mathematical model has been extended to allow calculations of NO formation under fuel-rich conditions. Particle combustion capability has been incorporated into the model and mixing effects can be handled with the macro-mixing option. Test cases have been run for the above options which indicate the correct order of magnitude predictions and the correct directional effect of combustion modifications on NO(x) emissions.