The Influence Of Biomass Gas Burning In Fluidized Bed On N₂O Emission

In order to reduce N₂O emission from circulating fluidized bed(CFB) biomass gas reburning were carried out in a fluidized bed.The influence of biomass gas burning in CFB on N₂O emission was studied.The results showed that the conversion efficiencies of N₂O was proportion to residence time at reduction zone,bed material height,temperature of reburning zone and inverse proportion to initial oxygen content in flue gas;when biomass gas was injected into the fluidized bed at B nozzle,the conversion efficiencies of N₂O emission was higher than that of A nozzle.The distance between nozzle A,B and air distributor was 0.1m, 0.2m,respectively;the catalytic activity of CaO on thermal decomposition of N₂O was higher than that of SiOO2.To make a deeper understanding of the reducing process of N₂O,the reaction kinetics were studied,in addition,the sensitivity and rate of production of N₂O and NO were analyzed.The results showed that the main decomposition paths of N₂O in the reburning process were described by the following reactions:N₂O+M=N₂+O+M;N₂O+H=N₂+OH,at the same time,the main paths were N₂O+M=N₂+O+M;N₂O+O=NO+NO;N₂O+O=N₂+O₂ when pure N₂O was injected or the initial oxygen content of flue gas was unequal to zero.