Oxidation of NO to NO2 by Hydrogen Peroxide and Its Mixtures with Methanol in Natural Gas and Coal Combustion Gases

The CombiNOx process includes a family of NOx control technologies (reburying, urea injection, methanol injection, and wet scrubbing) capable of reducing NOx emissions from stationary combustion sources by about 90%. However, methanol forms CO in flue gas as a by-product. Hydrogen peroxide and H20/CH30H mixtures decrease the amount of CO formed from CH30H and can substitute methanol in the CombiNOx process. This paper presents experimental and modeling results on H202 and H20/CH30H reactions with NO in a 300 kW combustor filing natural gas and coal. Maximum NO oxidation was achieved at 750-820 K for injection of H202 and a 1:1 H20/CH3 0H mixture, and at 850-930 K for CH30H injection. NO- to-N02 conversion of 90-98% and 64-76% was achieved at an additive/NO molar ratio of 1.5 during natural gas and coal firing, respectively. Influence of initial NO concentrations, the additive/NO ratio, oxygen and S02 concentrations, and the presence of fly ash on process prefermance is discussed. Experimental results are qualitatively explained by kinetic modeling. This paper is accepted for publication in Combustion Science and Technology.