| 摘要: | 碳的捕獲及封存是全球應對氣候變化的重要方法，可利用變壓吸附法捕獲煙道氣中二氧化碳，變壓吸附法為利用吸附劑對混合氣體中各成分之不同吸附選擇性來分離氣體的一種連續循環程序技術，本研究目的為捕獲燃煤電廠煙道氣中二氧化碳，使塔底產物二氧化碳達到純度95 %以上及回收率90 %以上。
以台中電廠再生吸附劑方法量測二氧化碳及氮氣對EIKME沸石13X的平衡吸附量得到修正因子f_(q_m )來調整等溫吸附模型所需參數後，藉由單塔三步驟程序捕獲燃煤電廠煙道氣實驗與模擬結果進行驗證，確認模擬程式的可靠性。
接著利用高壓吸附、同向減壓、兩次壓力平衡、真空脫附之變壓吸附三塔九步驟變壓吸附程序模擬，探討塔底二氧化碳純度及回收率變化。為了有效找出最佳操作條件，利用實驗設計(Design of Experiments, DOE)，以經除硫、除水後之12.69 %二氧化碳與87.31 %氮氣的煙道氣為進料，計算出最適化所需之操作條件，當進料壓力3.85 atm、抽真空壓力0.05 atm、同向減壓壓力0.2 atm、塔長60公分、步驟1/4/7時間400秒、步驟2/5/8時間209秒及步驟3/6/9時間120秒的操作條件下，能得到塔底產物二氧化碳純度96.16 %及回收率91.28%，能耗為1.11 GJ/t-CO2的最適化結果。
;Carbon capture and storage is an important method for global commitment to tackle climate change, and here pressure swing adsorption process (PSA) is used to capture carbon dioxide from flue gas in a thermal power plan. Pressure swing adsorption (PSA) is a cyclic process to separate gas mixtures based on the difference of adsorption capacity of each component on adsorbent. This study aims to capture carbon dioxide from flue gas of coal-fired power plant by PSA process for bottom product CO2 purity 95 % and recovery 90 %.
In order to obtain the correction factor (f_(q_m )) to modify the parameters of the extended Langmuir-Freundlich isotherm adsorption model, The equilibrium adsorption capacity of carbon dioxide and nitrogen on zeolite 13X was measured by the adsorbent regeneration method at Taichung coal-fired Power Plant. Then, the simulation is verified with experiments of 1-bed 3-step PSA process.
Next, the 3-bed 9-step PSA process is used with adsorption, cocurrent depressurization, vacuum, and twice pressure equalization to sperate flue gas (12.69 % CO2, 87.31 % N2) after desulphurization and water removal of Taichung coal-fired power plant.
Finally, in order to find the optimal operating conditions, this study combined the simulation of 3-bed 9-step PSA process with design of experiments (DOE) method. After simulation analysis, the bottom product CO2 purity is 96.16 % with 91.28 % recovery while at feed pressure 3.85 atm, vacuum pressure 0.05 atm, cocurrent depressurization 0.2 atm, bed length 60 cm, step 1/4/7 time 400 s, step 2/5/8 time 209 s, and step 3/6/9 time 120 s as the optimal results. The mechanical energy consumption was estimated to be 1.11 GJ/t-CO2. |
