High-Temperature Desulfurizing Sorbents of Low-Btu Gases from Coal for Combined-Cycle Power Generation

Abstract

High-temperature processes for desulfurization of low-Btu gases have been examined so that they may contribute considerably to the improvement of overall efficiency of power generation using combined cycle. By taking not only the capability of H₂S removal but also the high regenerability into account, the following reaction cycle is proposed.
BaCO₃ + H₂S → BaS + CO₂ + H₂O (900-1200°C)
BaS + CO₂ + H₂O → BaCO₃ + H₂S (80°C)
Both reactions were found to proceed well without forming any by-product. In comparison with CaO, BaCO₃, showed higher reactivity with lower concentration of H₂S and shorter time required for regeneration. The test for cyclic use based on the same sample suggested the high feasibility of the proposed reaction cycle.