煤浆洗涤法去除烟气中的SO_2

Removal of SO_2 from Flue Gas by Scrubbing Process with Coal Slurry

分别以高硫原煤、低硫原煤和中煤配制的煤浆作为洗涤介质,去除烟气中的SO2。反应温度高于40℃时,采用高硫原煤煤浆洗涤烟气,SO2去除率在90%以上;O2含量对SO2去除率影响不大;SO2去除率随其含量的增加而降低。低硫原煤煤浆同样可用于烟气脱硫,随温度的升高,煤浆pH的降低幅度和SO2去除率均增大,与用高硫原煤时的情况类似。中煤煤浆亦能有效去除烟气中的SO2,反应过程中煤浆pH的降低对SO2去除率的影响不大。在烟气脱硫的同时,3种煤中的黄铁矿均被不断浸出,浸出铁质量浓度随反应时间的延长和SO2去除率的增大而增加。

Three kinds of coal slurries were used as scrubbing medium to remove SO2 from flue gas, such as high-sulfur raw coal slurry, low-sulfur raw coal slurry and middling slurry. When flue gas is scrubbed by high-sulfur raw coal slurry at the reaction temperature above 40 ℃, the removal rate of SO2 is above 90% with little effect of O2 content, but it decreases with the increasing of SO2 content. Low-sulfur raw coal slurry can also be used to remove SO2 from flue gas. When the temperature increases, the pH fall of the coal slurry and the removal rate of SO2 all increase,just like the case of using high-sulfur raw coal slurry. Middling coal slurry can also remove SO2 from flue gas effectively with little effect of pH fall of the coal slurry on the removal rate of SO2 during the reaction process. Further more,iron in the three kinds of coal is leached out simultaneously during the flue gas desulfurization process, and the mass concentration of Fe increases with the extension of reaction time and the increase of SO2 removal rate.