生物质再燃脱除NO的特性

摘要

利用多功能脱硝实验台研究了花生壳、杨木、稻杆和玉米秸秆4种生物质的再燃脱除NO性能,以及工况参数对生物质再燃的影响.结果表明,相同工况下,花生壳再燃脱硝率最高、杨术次之、玉米秸秆最小,当再燃比(Rff)15%时,花生壳、杨木、稻杆和玉米秸秆的再燃脱硝效率分别为85.1%、80.3%、69.6%和67.2%.生物质粒径越小,荐燃脱硝率越高,随着再燃温度的升高,生物质再燃脱硝效率先升高后缓慢降低,1073K的脱硝效率最高.生物质最佳再燃区过量空气系数(SR)为0.6,最佳Rff和再燃区停留时间分别为20%和0.81s.SR=20%的典型工况下,生物质再燃脱硝效率达到79%～89%.%A multi-function denitration test bed was utilized to study the reburning NO reduction characteristics of four species of biomass such as peanut shell, cottonwood, straw and corn stalk, and the effect of operating parameters on NO removal efficiency with biomass as reburning fuels. The research results indicate that NO reductions of as high as 80％ are obtained with approximately 20％～25％ biomass heat input and the denitration efficiency of peanut shell, cottonwood, straw and com stalk are 85.1％, 80.3％, 69.6％ and 67.2％, respectively at the reburning fuel fraction(Rff) of 15％. Under the same conditions, peanut shell can attain the highest denitration efficiency followed by cottonwood, and corn stalk the least. the smaller the particle diameter ofbiomass, the higher the reburning denitration effectiveness. With the reburn zone temperature increasing, the biomass reburning denitration effectiveness firstly increases and then Changes slowly, and gains the highest denitration effectiveness at 1073K. The highest NO reductions are found at a stoichiometric ratio (SR) of 0.6. The best suitable Rff and the residence duration of the biomass are 20％ and 0.81 second, respectively. Under the typical operating conditions, NO removal efficiency of 79％～89％ is achieved by biomass reburning at Rff 20％.