Partitioning of nitrogenous species in the fuel-rich state of reburning

Control of combustion-generated nitrogen oxides by selective non-catalytic reduction

“…The first apparent demonstration of the reburning as a practical NO x reduction method applied to a full-scale coal-fired boiler in Japan by Mitsubishi was reported in the early 1980s where more than 50% NO reduction was achieved (Takahashi et al, 1983). Many researchers such as Glarborg and Hadvig (1991), Baulch et al (1992), Thorne et al (1986), Li et al (1996), Hura and Breent (1993) and Burch et al (1991) studied the reburn mechanism through elementary chemical reactions for various fuels. They concluded that two kinetic pathways control efficiency of reburning in which one involves reaction of hydrocarbon species with NO forming HCN, which in the presence of O or OH radical is converted to molecular nitrogen.…”

Effect of heterogeneous mechanisms during reburning of nitrogen oxide

“…For experiments with coal as the reburning fuel, the delivery system was modified to incorporate a laboratory-scale coal feeder. Details of this device have been reported elsewhere (Burch et al, 1991b). Part of the gas flow (usually helium) was diverted through the coal feeder as a carrier gas.…”

COMPUTATIONAL MODELING AND EXPERIMENTAL STUDIES ON NOx REDUCTION UNDER PULVERIZED COAL COMBUSTION CONDITIONS

“…Its effectiveness is usually lower than the hydrocarbon gases, and therefore, is usually discarded when the stoichiometry is higher than 0.7. However, Burch et al (1991a) found that the char derived from a North Dakota lignite had very high NO conversion (to HCN) efficiency, and the ash derived from the same lignite had very high HCN conversion (to NH ) efficiency. While NH is the dominant fixed nitrogen species during fuel rich 3 3 combustion of lignite (Chen et al 1982;Burch et al 1991a One of the objectives of this work was to study the effectiveness of CaC and CaS in 2 reducing NO under methane reburning conditions.…”