Formation of Acid Gases from Co-firing of Coal with Raw and Torrefied Biomasses

摘要

This work examined the emission for SO_2, NO_x, and CO_2 gases from the combustion of pulverized coals, raw and torrefied biomasses, and 50-50 wt% blends thereof. The fuel samples chosen for this work are a high-sulfur bituminous coal (Illinois #6), a low-sulfur sub-bituminous coal (Powder River Basin), a herbaceous biomass (corn straw) and a crop-related biomass (rice husk). All fuel samples were burned in a laboratory-scale electrically-heated drop-tube furnace (DTF), operated at 1400 K, and combustion emissions were measured in the furnace effluent. Coal and biomass particles were in the ranges of 75-90 μm and 90-150 μm, respectively. Results showed beneficial synergisms for almost all blend samples that can reduce the SO_2 and NO_x emissions to values below those predicted by linear interpolation of the SO_2 and NO_x emissions of the involved neat fuels.