Clean Technology, Vol.17, No.4, 389-394, December, 2011
PSA법을 이용하여 CH4/CO2/N2 혼합가스 중에서 메탄의 분리
Separation of CH4/CO2/N2 Mixture by Pressure Swing Adsorption
E-mail:
초록
바이오가스로부터 이산화탄소와 질소를 제거하기 위한 흡착공정은 많이 논의되고 있다. 특히 흡착공정 중에서 압력변동흡착(Pressure swing adsorption)공정은 에너지소모가 적고 가격이 경제적이기 때문에 기체의 분리와 정제를 위한 공정으로 적절하다. 물리적 흡착을 사용하는 PSA공정은 흡착과 탈착이 가능하다. 각 cycle단계의 구성은 가압, 주입 및 흡착, 압력 균등화, 감압 및 세정으로 이루어져있다. 본 실험에서 PSA공정은 이산화탄소와 질소를 제거하기 위한 흡착제로 zeolite 13X와 carbon molecular sieve (CMS)로 구성되어 있으며, 혼합 가스의 농도는 CH4/CO2/N2 (75:21:4 vol.%)의 비율을 갖고 있다. 각각 zeolite 13X와 CMS는 선택적으로 혼합가스로부터 질소와 이산화탄소를 흡착하여 분리하고 제거한다. 또한 CMS의 경우는 빠르게 분산되는 이산화탄소의 처리량이 높다. 상부탱크, 하부탱크, 주입탱크의 가스 조성은 TCD 검출기를 이용하는 gas chromatography (GC)에 의해서 측정되었다.
A compact adsorption-based process for removal of carbon dioxide and nitrogen from natural gas has been discussed. Among the adsorption-based processes, especially, the pressure swing adsorption (PSA) process has been a suitable unit operation for the purification and separation of gas because of low operation energy and cost. A step cycle is made up of pressurization, feed, equalization, blowdown and rinse. In this work, the PSA process is composed of zeolite 13X and carbon molecular sieve (CMS) for removal of carbon dioxide and nitrogen from mixed gas containing CH4/CO2/N2 (75:21:4 vol.%). A CMS selectively removes carbon dioxide and a zeolite 13X separates nitrogen from methane. CMS is investigated experimentally due to the high throughput of the faster diffusing component (CO2). The gas composition of top, bottom and feed tank was measured with the gas chromatography (GC) using TCD detector, helium as carrier gas and packed column for analysis of methane, carbon dioxide, and nitrogen.
- Gomes VG, Yee KWK, Sep. Purif. Technol., 28(2), 161 (2002)
- Cavenati S, Grande CA, Rodrigues AE, Chem. Eng. Sci., 61(12), 3893 (2006)
- Gim BJ, J. Korean OR/MS Society., 15, 37 (1990)
- Bum BS, Bae JH, Cho KM, J. KSEE., 24, 1365 (2002)
- Goo IN, Eom TK, J. KSEE., 24, 613 (2002)
- Xu X, Zhao X, Sun L, Liu X, J. Natural Gas Chemistry., 18, 167 (2009)
- Delgado JA, Uguina MA, Sotelo JL, Marcio BR, Rosario M, J. Natural Gas Chemistry., 16, 235 (2007)
- Kim MB, Bae YS, Choi DK, Lee CH, Ind. Eng. Chem. Res., 45(14), 5050 (2006)
- Boer JHD, Advances in Catalysis, Academic Press, New York (1956)
- Yang RT, Gas Separation by Adsorption Processes, Butterworth Publishers, Stoneham (1986)
- Chang D, Min J, Moon K, Park YK, Jeon JK, Ihm SK, Chem. Eng. Sci., 59(13), 2715 (2004)
- Anson A, Lin CCH, Kuznicki SM, Sawada JA, Chem. Eng. Sci., 64(16), 3683 (2009)
- Himeno S, Komatsu T, Fujita S, J. Chem. Eng. Data., 50, 369 (2005)
- Xu X, Zhao X, Sun L, Liu X, J. Natural Gas Chemistry., 17, 391 (2008)
- Bea YS, “Study on the Sorption Equilibrium and Kinetics of Seven Pure Gases on CMS,” M.S. Dissertation, Yonsei University, Seoul (2001)
- Lee H, Choi JW, Song HK, Na BK, Clean Technol., 7(1), 51 (2001)
- Choi JW, Lee H, Song HK, Suh SS, Na BK, Clean Technol., 14(1), 7 (2008)
- Choi JW, Nat BK, Clean Technol., 15(2), 75 (2009)