| 摘要 |
<p>PURPOSE:To employ versatile kinds of coals for reducing SO2, to raise the conversion efficiency, and to diminish the heat load of the reducing process and the loss of the reducing carbonaceous substance, by reducing a part of desorbed SO2 gas with carbonaceous substances into H2S, etc., and by making H2S react with the residual SO2 to perform Claus reaction. CONSTITUTION:The carbonaceous adsorbent 2 adsorbs SO2 in the waste gas sent from the boiler 1; an inert gas such as steam supplied from the line 20 is passed through the said carbonaceous adsorbent layer 2 in order to heat it to desorb SO2. The concentrated SO2 gas 9 is partly recycled to the adsorbent layer 2 for adjusting the concentration of SO2, and thereafter, the residual part of SO2 gas is branched into two lines 11 and 13, and the former branch 11 is reduced to reducing sulfur compound such as H2S, COS, by the coal supplied from the line 15, in the presence of moisture in the reducing furnace 3. Thus obtained sulfur compound is united with the residual concentrated SO2 gas of the line 13, and this gas mixture is fed to the catalyst-packed layer of the Claus furnace 4 wherein the sulfur compound is converted into the elemental sulfur. The gas is next sent to the sulfur condenser 5, the liquid sulfur is recovered through the line 17, and the gas deprived of sulfur is partly sent to the boiler 1 through the line 19, and the residual part is recycled to the SO2 adsorber 2 through the line 18.</p> |
