The non-isothermal pressure swing adsorption (PSA) process is used to separate binary syngas (60% H2 and 40% CO2) in this simulation study, the activated carbon is packed in the adsorption bed as the adsorbent. The feature of this study is to capture high concentration carbon dioxide and hydrogen gas, the former can be recovered and stored and the latter can be used in power generation industry.
This simulation program combined orthogonal collocation method and FORTRAN software to solve the problem. The temperature and concentration in the bed are integrated with respect to time by FORTRAN programming code. The simulation is stopped when the system reaches cyclic pseudo-steady state.
Single-bed four-step non-isothermal pressure swing adsorption process have been used in this study. The operating parameters and conditions used in this study are referred to the paper N. Casas et al. [1]. After confirming the simulation result is similar to the reference paper, we then discussed the influence of product concentration, product recovery and product purity under different operating conditions.
After several operating conditions discussion, when the feed linear velocity is 8.418 cm/s, both the capture rate and purity of carbon dioxide can be elevated to 62.7% and 60.3%, however, the recovery and the purity of hydrogen gas was then declined to 86% and 70.2%. When the feed temperature increased from 308.15 K to 318.15 K, both the capture rate and purity of carbon dioxide can be elevated to 47.8% and 46%; the recovery of hydrogen gas was also elevated to 91.4% and the purity of hydrogen gas has no significant change. Increasing the time of step two from 40 s to 60 s may elevate the recovery of hydrogen gas to 99.8% effectively, thus the purity of hydrogen gas decreased slightly to 75.1%. Decreasing the time of step two from 40 s to 20 s elevates both the capture rate and purity of carbon dioxide to 95% and 47.1%, in the mean time, the recovery of hydrogen gas declined to 73% and the purity was then elevated to 87.7%.

目錄
指導教授同意書
口試委員審定書
致謝……………………………………………………………………...iii
摘要……………………………………………………………………...iv
Abstract…………………………………………………………………..vi
目錄…………………………………………………………………….viii
圖目錄…………………………………………………………………...xi
表目錄………………………………………………………………….xiv
緒論……………………………………………………………...1
1.1 研究目的…………………………………………………………4
原理及文獻回顧………………………………………………...5
2.1 吸附現象…………………………………………………………5
2.1.1 吸附及脫附基本原理……………………………………….5
2.1.2 吸附種類…………………………………………………….6
2.1.3 吸附程序簡介……………………………………………….9
2.1.4 吸附劑的選擇……………………………………………...10
2.1.5 變壓吸附(PSA)基本操作步驟……………...……………..12
2.2 文獻回顧………………………………………………………..16
2.2.1 PSA程序之發展與改進………………………………...…16
2.2.2 質傳速率模式……………………………………………...19
2.2.3 以PSA製程回收二氧化碳的應用………………..………21
2.3 程序模擬範例的簡介…………………………………………..24
數學模式與研究方法………………………………………….29
3.1 數學模式之基本假設…………………………………………..30
3.2 統御方程式……………………………………………………..31
3.2.1 吸附平衡關係式…………………………………………...32
3.2.2 定義無因次變數…………………………………………...34
3.2.3 正交配置法………………………………………………...37
3.3 參數推導………………………………………………………..40
3.3.1 熱傳係數…………………………………………………...40
3.3.2 質傳係數與軸擴散係數…………………………………...41
3.4 起始條件與邊界條件…………………………………………..42
3.5 數學模式自由度分析…………………………………………..45
3.6 系統性能指標…………………………………………………..47
3.7 電腦求解步驟…………………………………………………..49
結果與討論…………………………………………………….51
4.1 程序模擬範例的驗證……………………….………...………..53
4.2 固定P_L、T、u、t_1~t_4，探討P_H之影響…………………………..57
4.3 固定P_H、T、u、t_1~t_4，探討P_L之影響……………………....60
4.4 固定P_H、P_L、u、t_1~t_4，探討T之影響……………….……..63
4.5 固定P_H、P_L、T、t_1~t_4，探討u之影響………………...…….66
4.6 固定P_H、P_L、T、u，探討t之影響………………..........……..69
4.6.1 固定t_1、t_3、t_4，探討t_2增加之影響……………….…….69
4.6.2 固定t_1、t_3、t_4，探討t_2減少之影響………………..……72
結論…………………………………………………………….75
符號說明………………………………………………………………...77
參考文獻………………………………………………………………...81
附錄 A、PSA程序模擬結果數據表…………………….……………85

圖目錄
圖2-1-1、吸附及脫附現象示意圖………………………….…………..6
圖2-1-2、雙塔式PSA程序裝置……………………………..………..14
圖2-1-3、吸附床內質量傳送區域之發展情形……………...……......15
圖2-3-1、PSA系統四階段操作示意圖……………………...……......28
圖3-1、電腦求解步驟流程圖…………………………………..……..50
圖4-1-1、PSA系統操作時的壓力分佈圖…………………………….54
圖4-1-2、PSA系統操作時的溫度分佈圖…………………………….54
圖4-1-3、PSA系統操作時的線性流速分佈圖……………………….55
圖4-1-4、氫氣與二氧化碳在第二階段的莫耳分率分佈圖……...…..55
圖4-1-5、氫氣在第二階段吸附塔內不同位置的莫耳分率分佈圖….56
圖4-1-6、二氧化碳在第二階段吸附塔內不同位置的莫耳分率分佈圖
…………………………………………………………………………...56
圖4-2-1、沖洗壓力(P_H)對二氧化碳的捕捉率與純度之影響………..58
圖4-2-2、沖洗壓力(P_H)對二氧化碳的產率之影響………….……….58
圖4-2-3、沖洗壓力(P_H)對氫氣的捕捉率與純度之影響……….…….59
圖4-2-4、沖洗壓力(P_H)對氫氣的產率之影響………….…….………59
圖4-3-1、沖洗壓力(P_L)對二氧化碳的捕捉率與純度之影響………...61
圖4-3-2、沖洗壓力(P_L)對二氧化碳的產率之影響…………………...61
圖4-3-3、沖洗壓力(P_L)對氫氣的捕捉率與純度之影響……………...62
圖4-3-4、沖洗壓力(P_L)對氫氣的產率之影響………...………………62
圖4-4-1、進料溫度(T)對二氧化碳的捕捉率與純度之影響…………64
圖4-4-2、進料溫度(T)對二氧化碳的產率之影響……………………64
圖4-4-3、進料溫度(T)對氫氣的捕捉率與純度之影響………..……..65
圖4-4-4、進料溫度(T)對氫氣的產率之影響…………………………65
圖4-5-1、進料線性流速(u)對二氧化碳的捕捉率與純度之影響……67
圖4-5-2、進料線性流速(u)對二氧化碳的產率之影響………………67
圖4-5-3、進料線性流速(u)對氫氣的捕捉率與純度之影響………....68
圖4-5-4、進料線性流速(u)對氫氣的產率之影響……………………68
圖4-6-1、增加第二階段操作時間(t_2)對二氧化碳的捕捉率與純度之影
響…………………………………………………..………...70
圖4-6-2、增加第二階段操作時間(t_2)對二氧化碳的產率之影響.......70
圖4-6-3、增加第二階段操作時間(t_2)對氫氣的捕捉率與純度之影響
…………………………………………………………………………...71
圖4-6-4、增加第二階段操作時間(t_2)對氫氣的產率之影響………....71
圖4-6-5、減少第二階段操作時間(t_2)對二氧化碳的捕捉率與純度之影
響…………………………………………………………….73
圖4-6-6、減少第二階段操作時間(t_2)對二氧化碳的產率之影響.......73
圖4-6-7、減少第二階段操作時間(t_2)對氫氣的捕捉率與純度之影響
…………………………………………………………………………...75
圖4-6-8、減少第二階段操作時間(t_2)對氫氣的產率之影響……...….75

表目錄
表2-1、物理吸附及化學吸附主要差異比較表………………..……....8
表2-3-1、PSA系統操作參數……………………………….……..….25
表2-3-2、PSA系統操作方向與條件………………………….…...…26
表2-3-3、PSA系統各階段操作時間及總操作時間…...………….….27
表3-3、PSA程序的性能指標…………………………………...…….48

[1] Casas Nathalie, Johanna Schell, Lisa Joss and Marco Mazzotti, “A
parametric study of a PSA process for pre-combustion CO2 capture”, Separation and Purification Technology, 104, pp.183–192, 2013.
[2] 經濟部能源局，我國燃料燃燒二氧化碳排放統計，2015年7月
[3] 朱育廷，正己醇/正戊醇水溶液在活性碳之雙成份吸附平衡，長
庚大學化工與材料工程學研究所碩士論文，2006.
[4] 吳文元，正丙醇/正丁醇水溶液在活性碳填充床之吸附及脫附研
究，長庚大學化工與材料工程學研究所碩士論文，2013.
[5] 盧贊生，用沸石作分離及吸附程序之研究，國立清華大學化學
工程研究所博士論文，1988.
[6] Skarstrom, C.W., “ Method and apparatus for fractionating gaseous mixtures by adsorption”, U.S. Patent 2,944,627, assigned to Esso Research and Engineering Company, 1960.
[7] Daniel Domine and Montgareuil Pierre Guerin De, “Process for separating a binary gaseous mixture by adsorption”, U.S. Patent 3,155,468, assigned to Union Carbide Corporation, 1964.
[8] Jones, R.L., G.E. Keller II, and R.C. Wells, “Rapid pressure swing adsorption process with high enrichment factor ” , U.S. Patent 4,194,892, assigned to Union Carbide Corporation, Mar. 25 1980.
[9] Berlin, N.H., “ Method for providing an oxygen-enriched environment”, U.S. Patent 3,280,536, assigned to Esso Research and Engineering Company, Oct. 1966.
[10] Marsh, W. D., F. S. Pramuk, R. C. Hoke, and C. W. Skarstrom, to Esso Research and Engineering Company, U. S. Patent 3,142,547, 1964.
[11] Kowler D.E. and R.H. Kadlec, “The optimal control of a periodic adsorber: Part I. Experiment”, AIChE J., vol. 31, no. 6, pp. 1207-1212, 1972.
[12] Tamura, T., “Absorption process for gas separation” , U.S. Patent 3,797,201, Mar. 1974.
[13] Yang, R.T., and S.J. Doong, “ Hydrogen purification by the multibed pressure swing adsorption process”, Reactive Polymers, Ion Exchangers, Sorbents, Vol.6, Iss.1, pp.7-13, Jun. 1987.
[14] Yamaguchi, T, Kobayashi, Y, U.S. Patent 5, 250, 88, 1993.
[15] Jones, R.L., G.E. Keller II, and R.C. Wells, “Rapid pressure swing
adsorption process with high enrichment factor ” , U.S. Patent 4,194,892, assigned to Union Carbide Corporation, Mar. 25 1980.
[16] Philip H. Turnock and Robert H. Kadlec, “Separation of nitrogen and methane via periodic adsorption”, AlChE Journal, vol. 17, no. 2 pp. 335-342, 1971.
[17] Farooq S. and D.M. Ruthven, “A comparison of linear driving force and pore diffusion-models for a pressure swing adsorption bulk separation process”, Chem. Eng. Sci., vol. 45, no. 1, pp. 107-115, 1990.
[18] Yang J., S. Han, C. Cho, C.H. Lee and H. Lee, “Bulk separation of hydrogen mixtures by a one-column PSA process”, Separations Technology, vol. 5, no. 4, pp. 239-249, 1995.
[19] Park J.H., J.N. Kim and S.H. Cho, “Performance analysis of four-bed H2 PSA process using layered beds”, AIChE J., vol. 46, no. 4, pp. 790-802, 2000.
[20] Chlendi, M., D. Tondeur, “Dynamic behaviour of layered columns in pressure swing adsorption”, Gas. Sep. Purif., vol.9, no.4, pp.231-242, 1995.
[21] Park J.H., J.N. Kim and S.H. Cho, “Performance analysis of four-bed H2 PSA process using layered beds”, AIChE Journal, vol. 46, no. 4, pp.790-802, 2000.
[22] Filipe V. S. Lopes, Carlos A. Grande and Alirio E. Rodrigues, “Activated carbon for hydrogen purification by pressure swing adsorption: Multicomponent breakthrough curves and PSA performance”, Chemical Engineering Science, 66, pp.303–317, 2011.
[23] Schell Johanna, Nathalie Casas, Dorian Marx, and Marco Mazzotti, “Precombustion CO2 capture by pressure swing adsorption (PSA):
Comparison of laboratory PSA experiments and simulations”, Ind. Eng. Chem. Res., 52, pp. 8311−8322, 2013.
[24] Chou Cheng-tung, Chih-hsiang Huang, Nai-chi Cheng, Yi-ting Shen,
Hong-sung Yang and Ming-Wei Yang, “Adsorption processes for CO2 capture from flue gas using polyaniline solid sorbent”, RSC Adv., 4, pp. 36307-36315, 2014.
[25] Ana M. Ribeiro, Joao C. Santos and Alirio E. Rodrigues, “PSA design for stoichiometric adjustment of bio-syngas for methanol production and co-capture of carbon dioxide”, Chemical Engineering Journal, 163, pp.355–363, 2010.
[26] Zhu L.Q., J.L. Tu and Y.J. Shi, “Separation of CO-CO2-N2 gas mixture for high-purity CO by pressure swing adsorption”, Gas Sep. Purif., vol. 5, no. 3, pp. 173-176, 1991.
[27] Xiao P., S. Wilson, G. Xiao, R. Singh and P. Webley, “Novel adsorption processes for carbon dioxide capture within an IGCC process”, Energy Procedia, vol. 1, no. 1, pp.631-638, 2009.
[28] McCabe W.L., J.C. Smith and P. Harriott, Unit Operations of
Chemical Engineering, Seventh Edition, McGraw-Hill Inc., New
York, 2005.
[29] 范庭瑋，以真實移動床吸附分離對位與間位二甲苯混合物之模
擬研究，長庚大學化工與材料工程學研究所碩士論文，2010.