全球暖化問題日益嚴重，其中二氧化碳及其他溫室氣體乃是造成全球暖化之主因。如何減緩二氧化碳之排放，已成為世界各國在降低溫室氣體影響方面的研究重點。而二氧化碳之排放最主要的來源為發電及工業界中利用天然氣或碳氫化合物產氫的製程上，目前經由氣化爐氣化煤炭後捕獲二氧化碳之技術，乃是先經由水煤氣轉化反應（water-gas shift reaction），再經過冷卻器降溫以將水汽去除後再加以捕獲二氧化碳。藉由變壓吸附法可以產出高濃度的氫氣做為能源使用，以應用於新興能源的供應上；而將二氧化碳回收封存則可減少其對溫室效應造成的影響。 變壓吸附法為一分離氣體混合物之連續性循環程序，利用氣體混合物中各成分對吸附劑之吸附能力的不同而產生的吸附選擇性來篩選氣體，並利用高壓吸附、低壓脫附以得到高濃度的產物。 本研究利用數值模擬的方法，模擬於常溫下，在含有一氧化碳、二氧化碳及氫氣等成份中，利用雙塔之變壓吸附製程與吸附劑的搭配，分離出二氧化碳及氫氣，並且探討各操作變數(如：進料壓力、吸附塔塔長、步驟時間等)對模擬結果的影響，尋求最佳的分離操作條件，以達到兼顧能源與環保的雙重目標。 Global warming has become more and more serious, which is caused by greenhouse gases. Cutting down the emission of CO2 has already become the major research target in the world. The main sources of CO2 include the processes of generating electric power and producing hydrogen from natural gas and hydrocarbon. The CO2 which comes from coal is generated by gasifier and the water-gas shift reaction step of the process. Pressure swing adsorption can purify hydrogen with high concentration to be used as energy source and recover carbon dioxide to decrease the impact on the greenhouse effect. Pressure swing adsorption is a cyclic process to separate gas mixtures based on the difference of adsorption capacity of each component on adsorbent. This technology consists of gas adsorption at high pressure and desorption at low pressure to produce high-purity product. This study plans to use dual-bed PSA process to separate high purity hydrogen and to capture CO2 from syngas, which contains CO, CO2 and hydrogen, at room temperature. The optimal operating condition is discussed by varying the operating variables, such as feed pressure, length of adsorber and step time. By PSA process, the goal of energy generation and environmental protection could be achieved at the same time.
