Effect of sulfation during carbonation on CO_2 capture in calcium looping cycle

Abstract： Two Canadian limestones with different properties were tested to determine the effect of SO2 during the carbonation of sorbent on the CO2 capture performance in Ca- looping. When the reaction gas is mixed with SO2, the carbonation ratio of the sorbent is always lower than that without SO2 for each cycle under the same conditions, and the sulfation ratio increases almost linearly with the increase in the cycle times. At 650 ℃, there is little difference in the carbonation ratio of the sorbent during the first four cycles for the two carbonation time, 5 and 10 rain at 0. 18% SO2. The indirect sulfation reaction that occurs simultaneously with the carbonation of CaO is responsible for the degradation of the sorbent for CO2 capture, and the carbonation duration is not the main factor that affects the ability of the sorbent. 680℃ is the best carbonation temperature among the three tested temperatures and the highest carbonation ratio can be obtained. Also, the sulfation ratio is the highest. The probable cause is the different effects of temperature on the carbonation rate and sulfation rate. A higher SO2 concentration will decrease the carbonation ratio clearly, but the decrease in the carbonation capability of the sorbent is not proportional to the increase of the SO2 concentration in flue gases.

IGCC电站二氧化碳捕集研究

近年来，CO2减排受到广泛重视。目前我国燃煤电站CO2排放量约占总排放量的1／2。在相当长时期内，我国以煤电为主的格局不会改变，控制煤基电站的CO2排放尤为重要，整体煤气化联合循环IGCC（Integrated Gasification Combined Cycle）电站是未来重要的洁净煤发电技术，其与CO2捕集技术的结合是目前能源领域的研究热点之一。