O2/CO2气氛下燃煤SO2排放特性的实验研究

在沉降炉实验台上通过在线烟气分析仪考查了燃煤烟气的组成以及燃烧气氛、CO2浓度、温度和燃料/氧气化学当量比对SO2的排放规律。结果表明，相同操作条件下O2/CO2燃烧可获得高达80%左右的CO2浓度，但烟气中CO含量明显高于O2/N2气氛下燃烧时的情况。高浓度CO2的存在使得SO2的排放较常规燃烧方式下有所降低，并且随着气氛中CO2浓度的增加呈递减趋势，但随着燃烧温度的升高，煤粉燃尽程度的增加以及其余含硫物相向SO2的转化使得其排放浓度逐步增加。在2种气氛下，SO2的释放浓度在贫燃料区随燃料/氧气化学当量比f的增加而增加，而在f大于1.2的富燃料区随燃料/氧气化学当量比的增加而降低。

Experimental Investigation on SO2 Emission Characteristic During Pulverized Coal Combustion in O2/CO2 Environment

The composition of flue gas was investigated in a drop tube furnace using flue gas on-line analyzer and the effects of combustion environment, CO2 concentration, fuel equivalence ratio and temperature on SO2 emission were discussed. Results show that the maximum CO2 concentration in O2/CO2 combustion mode is about 80% but the CO is higher than that in O2/N2 combustion process. The emission of SO2 in O2/CO2 combustion process is lower and it decreases with increasing CO2 concentration in the feeding gas. Increasing combustion temperature promotes SO2 emission because much more sulfur is released from the coal. Under two combustion environments, SO2 emission increases with the fuel equivalence ratio (f) in fuel lean region, and then appears to slightly decrease after 1.2.