CHARACTERIZATIONS OF DEPOSITED ASH DURING CO-FIRING OF WHITE PINE AND LIGNITE IN FLUIDIZED BED COMBUSTOR
Characterizations of ash deposits from co-firing/co-combusting of a woody biomass (i.e., white pine) and lignite coal were investigated in a fluidized-bed combustor using a custom designed air-cooled probe installed in the freeboard region of the reactor. Ash deposition behaviors on a heat transfer surface were comprehensively investigated and discussed under different conditions including fuel type, fuel blending ratios (20-80％ biomass on a thermal basis), and moisture contents. For the combustion of 100％ lignite, the compositions of the deposited ash were very similar to those of the fuel ash, while in the combustion of 100％ white pine pellets or sawdust the deposited ash contained a much lower contents of CaO, SO3, K2O and P2O5 compared with the fuel ash, but the deposited ash was enriched with SiO2, Al2O3 and MgO. A small addition of white pine (20％ on a heat input basis) to the coal led to the highest ash deposition rates likely due to the strong interaction of the CaO and MgO (from the biomass ash) with the alumina and silica (from the lignite ash) during the co-combustion process, evidenced by the detection of high concentrations of calcium/magnesium sulfates, aluminates and silicates in the ash deposits. Interestingly, co-firing of white pine pellets and lignite at a 50％ blending ratio led to the lowest ash deposition rates. Ash deposition rates in combustion of fuels as received with a higher moisture content was found to be much lower than those of oven-dried fuels.
ash deposition co-firing wood pellet sawdust coal chemical/mineralogical compositions fluidized bed
Yuanyuan Shao Jesse Zhu Fernando Preto Guy Tourigny Jinsheng Wang Chadi Badour Hanning Li Chunbao (Charles) Xu
Department of Chemical Engineering, Lakehead University, Thunder Bay, Ontario Chemical and Biochemic Chemical and Biochemical Engineering Department, University of Western Ontario, London, Ontario CANMET Energy Technology Centre ,Ottawa, Ontario Department of Chemical Engineering, Lakehead University, Thunder Bay, Ontario
国际会议
第20届国际流化床燃烧会议(20th International Conference on Fluidized Bed Combustion)
西安
英文
1041-1047
2009-05-18（万方平台首次上网日期，不代表论文的发表时间）