變壓吸附程序是一種分離氣體混合物的技術，根據不同氣體成份對吸附劑吸附能力的不同，進而利用吸附選擇性的高低來篩選氣體，再搭配吸附劑在高壓利於吸附、低壓利於脫附之特性，進行高低壓循環程序達到氣體分離的目的。具有容易操作、吸附劑可再生利用等優點。本研究利用變壓吸附法將二氧化碳濃縮以利後續封存，減少二氧化碳排放至大氣中，避免溫室效應的惡化。 本研究以雙塔六步驟變壓吸附法捕獲經水煤氣轉化後之合成氣中的二氧化碳，進料氣體以41.4%二氧化碳與58.6%氮氣模擬合成氣經過水煤氣轉化後的組成。選用13X沸石作為吸附劑，並將其填入吸附塔內進行突破及脫附曲線實驗，藉由改變不同的進料壓力與溫度，觀察其對突破曲線及脫附曲線之影響，並作為後續變壓吸附程序參數探討的基礎。 為降低實驗成本，利用實驗設計分析方法探討雙塔六步驟變壓吸附程序之二氧化碳捕獲實驗，並建立兩水準之部分因子設計(fractional factorial design)，探討各操作變因（進料壓力、溫度、逆向減壓壓力、進料加壓/同向減壓時間、高壓吸附/逆向減壓時間、高壓吸附/低壓沖洗時間）對製程的影響。實驗結果發現對純度而言，進料壓力及高壓吸附/逆向減壓時間為顯著因子；對回收率而言，各因子皆不顯著。在進料壓力3.45 atm、步驟一時間140秒、步驟二時間160秒、步驟三時間20秒、抽真空壓力0.05 atm、溫度358 K之操作條件下，純度可達90.39%、回收率79.73%。 最後以逐步回歸方式建立純度、回收率與變因之模型，以此模型來進行實驗預測、製程最佳化、量產製程變異性及提供系統操作之參數決策。 ;Pressure swing adsorption process is a technique used to separate gas mixtures according to the different adsorption capacities and selectivity toward adsorbent. Based on the property of adsorption at high pressure and desorption at low pressure, we can choose the appropriate processes to achieve the desired separation. Pressure swing adsorption process is used to concentrate carbon dioxide in order to mitigate the effects of global warming and reduce emissions. In this study, pressure swing adsorption process is utilized to separate CO2 and N2 from syngas after water gas shift reaction. The compositions of syngas are simulated as 41.4% CO2 / 58.6% N2. To purify 41.4% CO2 with balance N2 as a captured gas mixture, two-bed six-step pressure swing adsorption process using zeolite 13X were experimentally studied. Breakthrough curve experiments were carried out. These experimental results could be foundation of investigating pressure swing adsorption process. Two-bed pressure swing adsorption process was applied to carry out CO2 capture experiment. The design of experiment (DOE) of two-bed six-step pressure swing adsorption process. Pressurization / cocurrent depressurization time, adsorption / countercurrent depressurization time, adsorption / purge time, feed pressure, temperature, vacuum pressure are the factors of two-level six-factor fractional factorial design to investigate the change of CO2 concentration and recovery. The analysis shows that the main effects feed pressure and adsorption / countercurrent depressurization time were significant effects for purity. CO2 with 90.39% purity and 79.73% recovery was found at pressurization / cocurrent depressurization time 140 s, adsorption / countercurrent depressurization time 160 s, adsorption / purge time 20 s, temperature 358 K, feed pressure 3.45 atm and a fixed vacuum pressure of 0.05 atm. Finally, we build a model relating purity to factors and recovery to factors, and use a regression model to present the results of our designed experiment.
