常用的氟氯碳冷媒（Freon）皆有臭氧層破壞及全球暖化效應之虞，天然無機冷媒因而重新受到重視。使用氨水溶液的吸收式冷凍系統，不但以無機氨為冷媒，更以較低階的熱源來驅動，從節能與環保的觀點，利用氨水吸收式冷凍系統來達到制冷的效果值得做進一步的探討。
　　在氨水吸收式系統裡，是利用純氨的蒸發潛熱來吸收熱能以達到制冷的效果，氨的純度與制冷性能有甚大的關係，但由於氨與水具強親合性，目前爲了從氨水溶液中分離出高濃度的氨必須利用體積龐大的蒸餾塔，本文則嘗試使用分子篩獨特的分離技術來取代蒸餾塔。
　　爲了分析及確認取代之可行性，吾人利用ABSIM軟體模擬一實際的吸收式系統以確定氨水在蒸餾器前後的熱力狀態，以作為分子篩吸濕實驗的參考條件。實驗之目的包括測試分子篩的吸附能力與對氨氣與水氣的選擇性，以判斷分子篩是否可以取代龐大的蒸餾塔，使其在系統中扮演分離出濃氨的腳色。
　　從現有的測試結果顯示在溫度165℃、壓力20 atm、氨濃度為67﹪之氨水蒸氣，在經過單階段的分子篩後就可將氨濃度提高至 94﹪，此結果顯示分子篩對濃縮氨蒸氣是相當樂觀的。

　Many popular halocarbon refrigerants (Freon) are found to have Ozone Depletion potential (ODP) and Global Warming potential (GWP) , the application of using inorganic refrigerants are regaining many people’s attentions.
　Comparing to the traditional vapor compression refrigeration system, the advantages of ammonia-water absorption chiller use ammonia (an inorganic substance) as its refrigerant and use low grade heat instead of expensive electrical energy to power the system.
　The cooling ability of an ammonia-water absorption chiller is closely related to the evaporation of ammonia only (not water). Since NH3 and H2O have a strong affinity, the separation of NH3 from ammonia-water solution is rather difficult and usually requires a bulky distillation tower. In this study, a distinctive separation technique called molecular sieve is considered and studied to hopefully replace the distillation tower.
　ABSIM code is used simulate a typical absorption chiller, the conditions into and out of the distillation tower are obtained from simulation analysis. These conditions are then used as the reference conditions for ammonia-water separation tests by 3A molecular sieves. When the vapor mixture with 65％ ammonia at 165℃and 20atm passing through a single stage molecular sieves module, the percentage of ammonia can be increased to 94％.Other similar results indicate that the ability of molecular sieve to purify ammonia from NH3-H2O mixture is very promising.

參考文獻
[1] ASHRAE Handbook of Fundamentals, pp.12, 2004.
[2] 黃秉均，“吸收式冷凍空調系統之分析與設計”，慶齡工業研究中心，研究報告14，1988.6。
[3] 郭儒家，“吸收式熱泵之種類及其原理”，吸收式冷凍空調技術專輯，中華民國冷凍空調協會，pp.1-6，1999.12。
[4] McVain, J. W. in The Sorption of Gases and Vapors by solids,
Ruthedgeand Sons, London, Chapter 5, 1932.
[5] IUPAC Manual of Symbols and Terminology, appendix 2, Part 1,
Colloid and Surface Chemistry, Pure Appl. Chem. 1972, 31, 578.
[6] S.Alizadeh, F.Bahar and F.Geoola,“Design And Optimisation of an Absorption Refrigeration System Operated by solar Energy”, Solar Energy, Vol.22, pp.149-154, 1979.
[7] Kaushik S.C and S.C Bhardwaj,“Theoretical Analysis of Ammonia-Water Absorption Cycles For Refrigeration And Space Conditioning System”, Energy Research, Vol.6, pp.205-235, 1982.
[8] Grossman. G, Michelson.E“A Modular computer Simulation of Absorption System ”, ASHRAE Trans. 91, Partzb, pp.1808-1827, 2004.
[9] Wilkinson.W.H,“What Are the performance Limits for Double-Effect Absorpyion Cycles”, ASHRAE Trans, pp.2429-2441, 2004.
[10] Devalt R.C,“Triple Effect Absorption Chiller Utilizing Two Refrigeration Circuits”, U.S Patent No.4732008, 1998.
[11] P. Srikhirin, S. Aphornratans and S. Chungpaibulpatana,“A review of absorption technologies”, Renewable and Sustainable Energy Reviews, Vol.5, pp.343-372, 2001.
[12] F.S José, Jaime Sieres and Vázque Manuel,“Distillation column configurations in ammonia-water absorption refrigeration systems”, International Journal of Refrigeration, Vol.26, pp.28-34, 2003.
[13]S.A. Adewusi, Syed M. Zubair, “Second law based thermodynamic analysis of ammonia-water absorption systems.”, Energy Conversion and Management, Vol.45, pp. 2355-2369, 2004.
[14] Cronstedt, A.F. Akad. Handl. Stockholm,18.120,1756.
[15]http://www.siliporite.com/root_ceca/siliporite/gb/static/whatis.htm#zeolites.
[16] Ruthven, D.M., Principles of Adsorption and Adsorption Processes, John Wiley, New York (1984).
[17] Carton, A., González, G., Torre, A.I. and Cabezas, J.L., Separation of Ethanol-Water Mixtures Using 3A Molecular Sieve, J. Chem Tech. Biotechnol, 39, 125-132 (1987).
[18]Ruthven,D.M.,“Zeolites as Selective Adsorbents”, Chemical
Engineering Progress,1988, pp.42-50
[19] Carmo M.J. and Gubulin J.C. ,“Ethanol-Water Adsorption on Commercial 3A Zeolites：Kinetic and Thermodynamic Data”, Brazilian Journal of Chemical Engineering, Vol.14, No.3, Sept 1997。
[20] J.N. Barsema, N.F.A. van der Vegt., G.H. Koops, M. Wessling, “Carbon molecular sieve membranes prepared from porous fiber precursor.”, Journal of Membrane Science, 205, 239, 2002.
[21] J.N. Barsema, J. Balster, V. Jordan, N.F.A. van der Vegt, M. Wessling, “Functionalized Carbon Molecular Sieve membranes containing Ag-nanoclusters.”, Journal of Membrane Science, 219, 47, 2003.
[22] F.C. McQuiston, J. D. Parker and J.D. Spitler,“Heating, ventilating, and air conditioning-analysis and design”, Wiley, New York, 1994.
[23] E.P. Whitlow and J.S. Swearingen, Gas Age , pp.19, 1958.
[24] Zaltash.A, Grossman.G and R.C. Devault,“Simulation and Analysis of a four-effect Lithium Bromid-water Absorption Chiller”, ASHRAE Trans, part 2, pp.1302-1312, 2004.
[25] Grossman. G, Zaltash. A,“modular simulation of advanced absorption systems”, International Journal of Refrigeration”, pp.531-543, 2001.
[26] 邱秋燕，“固體吸附原理及其在空調系統之應用”，冷凍空調技術雜誌, Vol.7, No.6, pp.64-71, 1990.
[27] 陳禮溪，“分子篩應用”，觸媒與製程會刊, Vol.4, No.2, pp.67-71, 1995.
[28] 蕭濱振，“另類粉末冶金產品－分子篩”，粉末冶金會刊第27卷第2期2002年5月。
[29] http://www.sigmaaldrich.com/Brands/Aldrich/Tech_Bulletins/AL_1
43/Molecular Sieves.html
[30] http://www.hvacr.com.tw/mag/tech/rah02/RAH02-07.cfm
[31] J. W. Patrick, Porosity in Carbons, 1st ed., Edward Arnold,1995.
[32] 邱榮傑，“氨精餾塔程序動態模擬”，中國鋼鐵公司，1982。
[33] 河東 準、岡田 功，“最新蒸餾理論計算”，復漢出版社，台南，1999。
[34] R. C. Reid, J. M. Prausnitz and T. K. Sherwood,“The properties of gases and liquids”, McGraw-Hill, 1987.
[35] http://www.merck.com.tw/18_2f.asp
[36] http://www.ykchem.com/
[37] 黃秉均，“吸收式冷凍空調系統之分析與設計”，慶齡工業研究中心，研究報告19，1988.6。
[38] 黃盟欽，“碳分子篩/氧化鋁複合膜之製備及其特性之研究”，國立成功大學化學工程研究所碩士論文，2004。
[39] 吳聲彥，“利用薄膜蒸餾於氨水吸收式冷凍系統之可行性分析”，國立成功大學機械工程研究所碩士論文，2004。
[40] 陳柏岳，“氨/水吸收式循環應用特性解析研究”，國立台北科技大學冷凍空調研究所碩士論文，2002。
[41] Beaton C.F and G.H.Hewitt, physical property data for design engineer, Hemisphere, New York, 1989.
[42] F.J. Wang and J.S. Chiou“Integration of steam injection and inlet air cooling for a gas turbine generation system”, Energy Conversion and Management, Vol.45, pp. 15-26, 2004.
[43] D. S. Scott, F. A. Dullien, “Diffusion of Ideal Gases in Capillaries and Porous Solids.”,AlChe J.,8,113（1962）.
[44] K. Keizer, R. J. R. Uhlorn, V. T. Zaspalis, A. J. Burggraaf, “Microporous sol-gel modified membranes for hydrogen separation”
,Key Eng. Mater.,61,143,1991.
[45] K. Keizer, R. J. R. Uhlorn, R. J. Van Vuren, A. J. Burggraaf, “Gas separation mechanisms in microporous modified Ag/Al2O3 membranes.”Journal of Membrane Science,39,285,1988.
[46]Farber.E.A, F.M.F.Flanigan, L.Lopez and R.W.polifka,“Operation and Performance of the University of Florida Solar Air－conditioning System”, solar Energy, Vol.10, No.2, pp.91-95, 1996.
[47] ABSIM version 5.0, “Modular simulation of absorption systems user’s guide and reference”, Oak Ridge National Laboratory, Tennessee, 1998.
[48] C.P. Arora,“Refrigeration and Air Conditioning”, McGraw-Hill, 2001.
[49] W.F. Stoecker,“Design of Thermal System”, McGraw-Hill, 1989.
[50] Bejan, A., Tsatsaronis G. and Moran, M. J.,“Thermal Design and Optimization”, John Wiley & Sons, New York, 1996.
[51] Irvine, T.F. and Liley, P.E.,“ Steam and Gas Tables with Computer Equations”, Academic, Orlando.
[52] Roberts Engineeing: http://www.robertsengineering.f2s.com。
[53]http://www.sigmaaldrich.com/Brands/Aldrich/Tech_Bulletins/AL_143/Molecular_Sieves.html