燃煤氣化系統結合二氧化碳捕獲技術，乃是將氣化爐出來的合成氣經由水煤氣轉化反應後，透過冷卻器降溫再加以捕獲二氧化碳。藉由變壓吸附法可以純化高濃度的氫氣與捕獲大量的二氧化碳，前者用於發電而後者回收封存。本研究利用數值模擬的方法，模擬於常溫下，在含有水蒸汽、一氧化碳、二氧化碳及氫氣混合氣中，利用兩階段雙塔之變壓吸附程序與活性碳AC5-KS的搭配，於第一階段進行氫氣純化及第二階段進行二氧化碳濃縮回收，並且探討各操作變數對模擬結果的影響，尋求最佳的分離操作條件。第一階段H2-PSA雙塔八步驟最佳操作結果為氫氣純度達99.59%和回收率為86.17%，而二氧化碳回收率為99.23%。第二階段CO2-PSA雙塔六步驟最佳操作結果二氧化碳純度為90.49%和回收率為99.64%，而氫氣純度為94.82%。反應氣之出口氣體在常溫經過兩階段變壓吸附程序後，二氧化碳總回收率為98.87%。Gasification system means that coal is transformed to synthesis gas (syngas), which is then converted to hydrogen and carbon dioxide via water gas shift reaction. Then, carbon dioxide is captured after the temperature of mixture gases are reduced by condenser. Pressure swing adsorption (PSA) can then be utilized to purify hydrogen to high concentration and to capture carbon dioxide. The former can generate electrical power, the latter can be recovered and stored.This study plans to use a dual-bed PSA process with modified activated carbon AC5-KS to separate high-purity hydrogen and to capture carbon dioxide from syngas, which contains water vapor, carbon monoxide, carbon dioxide and hydrogen at room temperature. The optimal operating condition is discussed by varying the operating variables.In this study, the optimal result of dual-bed 8-step PSA process in the first H2-PSA stage produces high-purity hydrogen of 99.59% with a recovery of 86.17%, and the carbon dioxide recovery is 99.23%. The optimal result of dual-bed 6-step PSA process in the second CO2-PSA stage generates carbon dioxide purity and recovery of 90.49% and 99.64%, respectively. The hydrogen purity is 94.82%. By two stage PSA process, the total carbon dioxide recovery from syngas is 99.23%.
