噴霧器對於空氣污染之去除吸收為一個重要的工具。為了解空氣污物在噴霧器中之質傳特徵，本研究為理論分析四種空氣污染物，二氧化硫(SO2)、氯化氫(HCl)、氨氣(NH3)與硝酸(HNO3)，分別在噴霧器中被液滴吸收，使用數值方法求解。液滴之數量密度(number density)為103-106 cm-3與液滴半徑為30 μm。假設在液滴外部一氣泡為液滴之間交作用影響範圍，模擬結果顯示質量擴散數(mass diffusion number)與液滴之數量密度為兩個影響質傳過程之重要因素。當質量擴散數較大時，掃氣波(scavenging wave)之範圍也變大，使得液滴之間交互作用影響增強。數量密度的增加，促進空氣污染物有氣相質傳至液相，然而，單一顆的吸收量是減少的。最後，根據溶質之質量分布情形，提供使用噴霧器吸收此四種空氣污染物之建議操作參數。
另一個重要的環境議題為全球暖化，二氧化碳為溫室氣體中最主要之成分。因此，本研究之第二部分為理論方法分析探討一靜止單一液滴捕捉二氧化碳之質傳現象。分析求解方法為在氣相使用相似方法，液相為使用分離變數法，交界面部分，有限差分方法應用於連接兩相之間二氧化碳擴散。考慮三個不同的吸收劑，Selexol、水與Rectisol，分別探討其捕捉二氧化碳之過程。Selexol與水的操作壓力與溫度分別為30-60 atm和303-333 K，Rectisol為30-60 atm與240-270 K。模擬的結果顯示，操作溫度增加，使用Selexol與Rectisol捕捉二氧化碳之捕捉量減少。吸收時間受溫度影響較吸收量大，因此二氧化碳吸收率隨著溫度增加而上升。與其他二種吸收劑相比，Rectisol具有最高捕捉二氧化碳之能力，其吸收速率大於其他二個吸收劑的一個數量級。

Sprays are important tools for removing air pollutants through absorption. To recognize the mass transport characteristics of air pollutants in sprays, four different air pollutants of sulfur dioxide (SO2), hydrogen chloride (HCl), ammonia (NH3), and nitric acid (HNO3) absorbed by droplets in sprays are analyzed theoretically in association with a numerical method. The number density of droplet in a spray is in the range of 103-106 cm-3 and the droplet radius is 30 μm. By conceiving a bubble as the sphere of influence of droplet-droplet interaction, the predictions indicate that the mass diffusion number and the number density are two important factors in determining the absorption process and results. When the mass diffusion number is larger, the radius of scavenging wave is increased and the effect of the droplet mutual interaction is thus intensified. An increase in number density facilitates the mass transfer of air pollutants from the gas phase to the liquid phase. However, the uptake amount of solute by individual droplets is abated. At last, according to the mass distributions of the solutes in the liquid (droplet) phase, the appropriate number densities in sprays for the absorption of the four air pollutants are suggested.
Another important environmental issue is global warming and CO2 is the major greenhouse gas in the atmosphere. Hence the second part of this thesis is developing a theoretical method to analyze carbon dioxide capture by a stationary single droplet for evaluating the fundamental mass transfer behavior. In the method, the gas-phase diffusion is predicted using a similarity method and the liquid-phase diffusion is approached by means of the technique of separation of variable. At the interface, a finite difference method is applied to connect CO2 diffusion between the two phases. The individual capture process of CO2 by three different absorbents of Selexol, Rectisol and water, are taken into account. The operating pressure and temperature of Selexol and water are in the ranges of 30-60 atm and 303-333 K, respectively, and they are 30-60 atm and 240-270 K for Rectisol. The analysis indicates that an increase in temperature decreases the capture amount of CO2 and the absorption time by Selexol and Rectisol droplets. The absorption time is more sensitive to the operating temperature than the capture amount. As a result, the absorption rates of CO2 by the droplets are increased when the temperature increases. Among the three absorbents, Rectisol has the highest capacity to capture CO2 and its absorption time is in a comparable state to the other two absorbents. This results in that its absorption rate is larger than the others by an order of magnitude.

1.Aguado, S., Polo, A.C., Bernal, M.P., Coronas, J., Santamar´ıa, J., “Removal of pollutants from indoor air using zeolite membranes,” Journal of Membrane Science, Vol.240, pp.159-66, 2004.
2.Bandyopadhyay, A., Biswas, M.N., “Modeling of SO2 scrubbing in spray towers,” Science of the Total Environment, Vol.383, pp.25-40, 2007.
3.Bandyopadhyay, A., Biswas, M.N., “Critical flow atomizer in SO2 spray scrubbing,” Chemical Engineering Journal, Vol.139, pp.29-41, 2008.
4.Barker, D.J., Turner, S.A., Napier-Moore, P.A., Clark, M., Davison, J.E., “CO2 capture in the cement industry,” Energy Procedia, Vol.1, pp.87-94, 2009.
5.Bouillona, B.A., Hennes, S., Mahieux, C., “ECO2 : Post-combustion or Oxyfuel - A comparison between coal power plants with integrated CO2 capture,” Energy Procedia, Vol.1, pp.4015-22, 2009.
6.Bozorgi, Y., Keshavarz, P., Taheri, M., Fathikaljahi, J., “Simulation of a spray scrubber performance with Eulerian/Lagrangian approach in the aerosol removing process,” Journal of Hazardous Materials, Vol.B137, pp.509-17, 2006.
7.Breckenridge, W., Holiday, A., Ong, J.O.Y., Sharp, C., “Use of SELEXOL® Process in Coke Gasification to Ammonia Project,” Laurance Reid Gas Conditioning Conference, 2000.
8.Brogren, C., Karlosson, H.T., “Modeling the absorption of SO2 in a spray scrubber using the penetration theory,” Chemical Engineering Science, Vol. 52, pp. 3085-99, 1997.
9.Burr, B., Lyddon, L., “A Comparison of Physical Solvents for Acid Gas Removal,” Bryan Research & Engineering Inc, 2008.
10.Chen, C., Rubin, E.S., “CO2 control technology effects on IGCC plant performance and cost,” Energy Policy, Vol.37, pp.915-24, 2009.
11.Chen, W.H., “An analysis of gas absorption by a liquid aerosol in a stationary environment,” Atmospheric Environment, Vol.36, pp.3670-83, 2002.
12.Chen, W.H., “Atmospheric ammonia scavenging mechanisms around a liquid droplet in convective flow,” Atmospheric Environment, Vol.38, pp.1107-16, 2004.
13.Chen, W.H., “Scavenging waves and influence distances of gas absorption around single liquid aerosols in clouds,” Atmospheric Environment, Vol.40, pp.500-11, 2006a.
14.Chen, W.H., “Air pollutant absorption by single moving droplets with drag force at moderate Reynolds numbers,” Chemical Engineering Science, Vol.61, pp.449-58, 2006b.
15.Chen, W.H., Hou, Y.L., Hung, C.I., “A theoretical analysis of the capture of greenhouse gases by single water droplet at atmospheric and elevated pressures,” Applied Energy, Vol.88, pp.5120-30, 2011.
16.Chen, W.H., Hou, Y.L., Hung, C.I., “Influence of droplet mutual interaction on carbon dioxide capture process in sprays,” Applied Energy, Vol.92, pp.185-93, 2012.
17.Chen, W.H., Lu, J.J., “Microphysics of atmospheric carbon dioxide uptake by a cloud droplet containing a solid nucleus,” Journal of Geophysical Research: Atmospheres, Vol.108(D15), pp.4470-8, 2003.
18.Chen, W.H., Chen, S.M., Hung, C.I., “A theoretical approach of absorption processes of air pollutants in sprays under droplet-droplet interaction,” Science of the Total Environment, Vol.444, pp.336-46, 2013.
19.Chiesa, P., Consonni, S., Kreutz, T., Williams, R., “Co-production of hydrogen, electricity and CO2 from coal with commercially ready technology. PartA: Performance and emissions,” International Journal of Hydrogen Energy, Vol.30, pp.747-769, 2005.
20.Descamps, C., Bouallou, C., Kanniche, M., “Efficiency of an integrated gasification combined cycle (IGCC) power plant including CO2 removal,” Energy, Vol.33, pp.874-881, 2008.
21.Dwivedi, P., Gaur, V., Sharma, A., Verma, N., “Comparative study of removal of volatile organic compounds by cryogenic condensation and adsorption by activated carbon fiber,” Separation and Purification Technology, Vol.39, pp.23-37, 2004.
22.Ebert, F., Buttner, H., “Recent investigations with nozzle scrubbers,” Powder Technology, Vol.86, pp.31-6, 1996.
23.Elperin, T., Fominykh, A., “Conjugate mass transfer during gas absorption by falling liquid droplet with internal circulation,” Atmospheric Environment, Vol.39, pp.4575-82, 2005.
24.Elperin, T., Fominykh, A., Krasovitov, B., “Scavenging of soluble trace gases by falling rain droplets in inhomogeneous atmosphere,” Atmospheric Environment, Vol. 44, pp.2133-9, 2010.
25.Farla, J.C.M., Hendriks, C.A., Blok, K., “Carbon dioxide recovery from industrial processes,” Climatic Change, Vol.29, pp.439-461, 1995.
26.Fenger, J., “Air pollution in the last 50 years—from local to global,” Atmospheric Environment,Vol.43, pp.13-22, 2009.
27.Galloway, J.N., Levy, H.I.I., Kasibhatla, P.S., “Year 2020: consequences of population growth and development on deposition of oxidized nitrogen,” Ambio, Vol.23(2), pp.120-3, 1994.
28.Gamisans, X., Sarrà, M., Lafuente, F.J., “Gas pollutants removal in a single- and two-stage ejector–venturi scrubber,” Journal of Hazardous Materials, Vol.B90, pp.251-66, 2002.
29.Gibbins, J., Chalmers, H. “Carbon capture and storage,” Energy Policy, Vol.36, pp.4317-22, 2008.
30.Gielen, D., “CO2 removal in the iron and steel industry,” Energy Conversion and Management, Vol.44, pp.1027-1037, 2003.
31.Gray, P.G., “A fundamental study on the removal of air pollutants (sulfur dioxide, nitrogen dioxide and carbon dioxide) by adsorption on activated carbon,” Gas Separation & Purification, Vol.7, NO.4, pp.213-24, 1993.
32.Hackett, G.A., Gerdes, K., “Trace Species Partitioning as Affected by Cold Gas Cleanup Conditions: A Thermodynamic Analysis,” National Energy Technology Laboratory, 2011.
33.Hochgesand, G., “Rectisol and Purisol,” Industrial and Engineering chemistry, Vol.62 (7), pp.37-43, 1970.
34.Hufton, J., Golden, T., Quinn, R., Kloosterman, J., Wright, A., Schaffer, C., Hendershot, R., White, V., Fogash, F., “Advanced Hydrogen and CO2 Capture Technology for Sour Syngas,” Energy Procedia, Vol.4, pp.1082-1089, 2011.
35.Javed, K.H., Mahmud, T., Purba, E., “The CO2 capture performance of a high-intensity vortex spray scrubber,” Chemical Engineering Journal, Vol.162, pp.448-456, 2010.
36.Johnson, J.E., Homme Jr, A.C., “Selexol solvent process reduces lean, high-CO2 natural gas treating costs,” Energy Progress, Vol.4(4), pp.241-8, 1984.
37.Kaneco, S., Katsumata, H., Suzuki, T., Ohta, K., “Electrochemical reduction of carbon dioxide to ethylene at a copper electrode in methanol using potassium hydroxide and rubidium hydroxide supporting electrolytes,” Electrochimica Acta, Vol.51, pp.3316-21, 2006.
38.Keshavarz, P., Bozorgi, Y., Fathikalajahi, J., Taheri, M., “Prediction of the spray scrubbers' performance in the gaseous and particulate scrubbing processes,” Chemical Engineering Journal, Vol.140, pp.2-31, 2008.
39.Kohl, A.L., Nielsen, R.B., “Gas Purification,” Gulf Professional, 1997.
40.Lawal, A., Wang, M., Stephenson, P., Obi, O., “Demonstrating full-scale post-combustion CO2 capture for coal-fired power plants through dynamic modelling and simulation,” Fuel, Vol.101, pp.115-28, 2012.
41.Li, J., Mundhwa, M., Henni, A., “Volumetric properties, viscosities, refractive indices, and surface tensions for aqueous Genosorb 1753 solutions,” Journal of Chemical & Engineering Data, Vol.52, pp.955-8, 2007.
42.Li, L., Zhao, B., “Numerical Simulation of Gas and Liquid Flow within a Vortex Spray Tower,” Energy Procedia, Vol.16, pp.1072-77, 2012.
43.Li, S., Robin, S., “Rectisol wash process simulation and analysis,” Journal of Cleaner Production, Vol.39, pp.321-28, 2013.
44.Li, Y., Liu, Y., Zhang, H., Liu, W., “Carbon dioxide capture technology,” Energy Procedia, Vol.11, pp.2508-15, 2011.
45.Lu, Y., Ye, X., Zhang, Z., Khodayari, A., Djukadi, T., “Development of a Carbonate Absorption-Based Process for Post-Combustion CO2 Capture: the Role of Biocatalyst to Promote CO2 Absorption Rate,” Energy Procedia, Vol.4, pp.1286-93, 2011.
46.Lunsford, K., Mcintyre, G., “Decreasing Contactor Temperature Could Increase Performance,” Bryan Research & Engineering Inc, 2006.
47.Makri, A., Stilianakis, N.I., “Vulnerability to air pollution health effects,” International Journal of Hygiene and Environmental Health, Vol.211, pp.326-36, 2008.
48.Mak, J., Wierenga, D., Nielsen, D., Graham, C., Oil and Gas Group, Fluor Enterprises, Inc., Aliso Viejo, California, “New Physical Solvent Treating Configurations for Offshore High Pressure CO2 Removal,” Offshore Technology Conference, 2003.
49.Mores, P., Scenna, N., Mussati, S., “Post-combustion CO2 capture process: Equilibrium stage mathematical model of the chemical absorption of CO2 into monoethanolamine (MEA) aqueous solution,” Chemical Engineering Research and Design, Vol.89, pp.1587-99, 2011.
50.Myers, G.E., “Analytical Methods in Conduction Heat Transfer,” Genium Pub. Corp., New York, 1987.
51.Olajire, A.A., “CO2 capture and separation technologies for end-of-pipe applications – A review,” Energy, Vo1.35, pp.2610-28, 2010.
52.Panda, A.K., Singh, R.K., Mishra, D.K., “Thermolysis of waste plastics to liquid fuel: a suitable method for plastic waste management and manufacture of value added products—a world prospective,” Renewable and Sustainable Energy Reviews, Vol.14, pp. 233-48, 2010.
53.Percya, K.E., Ferretti, M., “Air pollution and forest health: toward new monitoring concepts,” Environmental Pollution, Vol.130, pp.113-26, 2004.
54.Poling, B.E., Prausnitz, J.M., OC John, P., “The Properties of Gases and Liquids,” McGRAW-HILL, New York, 2001.
55.Qian, Z., Chapman, R.S., Hu, W.,Wei, F., Korn, L.R., Zhang, J., “Using air pollution based community　clusters to explore air pollution health effects in children,” Environment International, Vol.30, pp.611-20, 2004.
56.Santos, S., Jones, K., Abdul, R., Boswell J., Paca, J., “Treatment of wet process hardboard plant VOC emissions by a pilot scale biological system,” Biochemical Engineering Journal, Vol.37, pp.261-70, 2007.
57. Sarkar, S., Meikap, B.C., Chatterjee, S.G., “Modeling of removal of sulfur dioxide from flue gases in a horizontal cocurrent gas–liquid scrubber,” Chemical Engineering Journal, Vol.131, pp. 263-71, 2007.
58. Sawyer, R.F., “The formation and destruction of pollutants in combustion processes: Clearing the air on the role of combustion research,” Eighteenth Symposium (International) on Combustion, Vol.18, pp.1-22, 1981.
59. Seinfeld, J.H., “Atmospheric chemistry and physics of air pollution,” Wiley, New York, 1986.
60. Seinfeld, J.H., Pandis, S.N., “Atmospheric Chemistry and Physics,” Wiley, New York, 1998.
61.Sipöcz, N., Tobiesen, F.A., Assadi, M., “The use of Artificial Neural Network models for CO2 capture plants,” Applied Energy, Vol.88, pp.2368-76, 2011.
62. Slack, A.V., Holliden, G.A., “Sulfur dioxide removal from waste gases,” Noyes Data Corporation, Park Ridge, New Jersey, 1975.
63.Strauss, W.A., “Partial Differential Equations :an Introduction,” Wiley, New York, 2008.
64.Strube, R., Manfrida, G., “CO2 capture in coal-fired power plants—Impact on plant performance,” International Journal of Greenhouse Gas Control, Vol.5, pp.710-26, 2011.
65.Tippayawong, N., Thanompongchart, P., “Biogas quality upgrade by simultaneous removal of CO2 and H2S in a packed column reactor,” Energy, Vol.35, pp.4531-35, 2010.
66. Ward, D.E., Hardy, C.C., “Smoke emissions from wildland fires,” Environment International, Vol.17, pp.117-34, 1991.
67. Xu, Y., Schutte, R.P., Hepler, L.G., “Solubilities of Carbon Dioxide, Hydrogen Sulfide and Sulfur Dioxide in Physical Solvents,” The Canadian Journal of Chemical Engineering, Vol.70, pp.569-73, 1992.
68. Zhou, W., Zhu, B., Chen, D., Zhao, F., Fei, W., “Technoeconomic assessment of China’s indirect coal liquefaction projects with different CO2 capture alternatives,” Energy, Vol.36, pp.6559-66, 2011.
69. 陳維新，“空氣污染與控制，” 高立圖書有限公司，2012年02月。
70. 陳維新， “能源概論，” 高立圖書有限公司，2012年08月。