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研究生:翁怡玫
研究生(外文):Weng, Yi-Mei
論文名稱:以海綿為氣膠數目分徑採樣介質之探討
論文名稱(外文):The Study of Aerosol Number Size-Selective Medium Using Porous Foams
指導教授:陳志傑陳志傑引用關係
指導教授(外文):Chen, Chih-Chieh
學位類別:碩士
校院名稱:國立臺灣大學
系所名稱:職業醫學與工業衛生研究所
學門:醫藥衛生學門
學類:公共衛生學類
論文出版年:2002
畢業學年度:90
語文別:中文
論文頁數:64
中文關鍵詞:填充密度表面風速海綿穿透率
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摘 要 (1)
已有資料顯示大氣氣膠的暴露,氣膠數目濃度對於疾病與暴露之間的相關性比氣膠質量濃度要高,因此氣膠數目濃度被認為比氣膠質量濃度更適合做為暴露評估的標的。此外,氣膠在呼吸道中的沈積分佈大多決定於它的粒徑。因此,有必要研發氣膠數目分徑採樣器以便能夠準確的評估次微米微粒所造成的健康危害。
本研究利用海綿做為分徑介質,主要的操作變因有海綿孔隙度,海綿厚度,海綿填充密度以及過濾時之表面風速。實驗中以Di-octyl phthalate 作為測試微粒。分別以定量輸出霧化器和超音波霧化噴嘴,產生多粒徑分佈的次微米微粒和微米微粒。並利用微粒電移動度掃瞄分徑器和氣動微粒分徑器,監測通過海綿濾材前後的氣膠濃度及粒徑分佈。產生的氣膠藉由經過一氣膠靜電中和器使產生的氣膠帶電達波滋曼平衡分佈。本研究選擇國際輻射防護委員會所定義的輕度工作者的呼吸道微粒沈積率曲線,作為主要的目標曲線。
實驗結果顯示當海綿的孔隙度、填充密度和過濾時表面風速增加,海綿過濾時的最易穿透粒徑都會減小。在實驗的過程中所能得到最大的海綿孔隙度和填充密度分別為100ppi和0.2。藉由表面風速的調整,最易穿透粒徑可以移至0.25mm,也就是目標曲線的最易穿透粒徑。進一步藉由調整海綿厚度使氣膠穿透率曲線能夠符合目標曲線。氣膠穿透率曲線的寬窄亦會受到填充密度、海綿纖維直徑和表面風速的影響,藉著調整這些變項可以更符合目標曲線。
關鍵字:填充密度、表面風速、PU海綿
摘 要(2)
彈性聚氨酯海綿能夠符合多種過濾作用的設計準則,這些過濾作用包括了由空氣、氣體和液體中移除粉塵和污染微粒(過濾);收集工廠設備中蒸發的油滴(除去霧滴);作用於蒸汽表面(保濕)和清除溢出的油滴(油/水分離)。海綿由於具開放性孔洞的骨架結構,因此在過濾時相對於其他濾材的壓降較低;由於海綿內有97%的體積是空的,所以有較大的微粒負載量,而且海綿的張力高且不易斷裂,所以能夠成為組裝簡便並節省空間的產品。除此之外,使用過濾海綿還有許多其他的優點。在本研究中,特別還探討海綿的填充密度對過濾特性的影響,因為過濾海綿可以經由壓縮而增加填充密度,而不需改變它的纖維直徑。
研究中以Di-octyl phthalate 作為測試微粒並使用兩種常用的氣膠產生器,產生多粒徑分佈的氣膠: 定量輸出霧化器和超音波霧化噴嘴。前者產生的微粒粒徑範圍約為30nm到1mm,後者產生的微粒粒徑範圍則主要都大於1mm。在各個產生器下方各放置一氣膠靜電中和器,使微粒達到波茲曼電量平衡。使用的粒徑分徑儀為微粒電移動度掃瞄分徑器(量測範圍為20nm~0.6mm)和氣動微粒分徑器(0.8~30mm)。通過海綿所產生的壓降是以斜臂式壓力計量測。本研究中將以單一纖維理論所模擬的穿透率曲線與實驗數據作比對。
實驗結果顯示過濾時表面風速增加,則壓降呈線性增加,填充密度與孔隙度增加時,壓降都呈增加的趨勢。當海綿的填充密度、孔隙度和過濾時表面風速增加,海綿過濾時的最易穿透粒徑都會減小。填充密度與孔隙度增加,不論任何粒徑的微粒其穿透率都會減少。相對來說,過濾時的表面風速增加,大粒徑的微粒其穿透率減少,但小粒徑的微粒其穿透率卻上升。整個穿透率曲線在低填充密度時,隨著表面風速增加而上升,但在高填充密度時,先隨著表面風速增加而上升,表面風速繼續上升時,整個穿透率曲線卻隨著繼續上升的表面風速而下降了。就實驗值來看,孔隙度對整個穿透率曲線的寬度影響最大。另外,就較小的微粒來看,填充密度較低、孔隙度較大與表面風速較低時有較好的過濾品質。
關鍵字:海綿、穿透率、填充密度
目錄(1)
摘要………………………………………………………………………………………i
目錄 ii
圖目錄 iii
前言………………..…………………………………………………………………….1
文獻探討…………………………………………………………………...….………...3
次微米微粒的暴露與健康危害……………………………………………………...3
微粒之肺部沉積……………………………………………………………………...4
氣懸微粒過濾機制…………………………………………………………………...6
海綿運用於分徑裝置………………………………………………………………...8
實驗方法……………………………………………………………………………….11
測試系統的建置…………………………………………………………………….11
實驗步驟…………………………………………………………………………….12
結果與討論…………………………………………………………………………….15
表面風速對過濾特性之影響…………………………………….…………………15
海綿填充密度對過濾特性之影響…………………………………….……………15
海綿纖維直徑對過濾特性之影響……………………………………….…………16
尋求符合國際輻射防護委員會定義曲線的海綿………………………………….17
結論與建議…………………………………………………………………………….19
參考文獻……………………………………………………………………………….20
目錄(2)
摘要……………………………………………………………………………………..i
目錄…………………………………………………………………………………….ii
圖目錄…………………………………………………………………………………iii
前言………………..…………………………………………………………………...1
文獻探討…………………………………………………………………...….……….2
海綿的種類…………………………………………………….……………………2
海綿過濾相關研究………………………………………………………………….3
氣懸微粒過濾機制………………………………………………………………….6
過濾造成之壓降………………………………………………………………….…8
實驗方法……………………………………………………………………………...10
測試系統的建置…………………………………………………………………...10
實驗步驟…………………………………………………………………………...11
結果與討論…………………………………………………………………………...14
海綿過濾時產生之壓降…………………………………….……………………..14
實驗值、海綿半經驗式與單一纖維理論所模擬的穿透率曲線之比較………...14
填充密度對過濾特性之影響……………………………………….……………..14
結論與建議…………………………………………………………………………...18
參考文獻……………………………………………………………………………...19
參考文獻(1)
Breum, N. O. (2000) The dust holding capacity of porous plastic foam used in particle size-selective sampling. J. Aerosol Sci. Vol. 31, No. 3, pp. 379-385.
Brown, R. C. (1980) Porous foam size selectors for respirable dust samplers. J. Aerosol Sci. Vol. 11, pp. 151-159.
Chen, C. C., Lai, C. Y., Shih, T. S., Yeh, W. Y. (1998) Development of respirable aerosol samplers using porous foams. American Industrial Hygiene Association Journal Vol. 59, pp. 766-773.
Chung, K. Y. K., Aitken, R. J., Bradley, D. R. (1997) Development and testing of a new sampler for welding fume. Ann. Occup. Hyg., Vol. 3, pp. 355-372.
Donaldson, K., Li X. Y. & MacNee, W. (1998) Ultrafine (nanometer) particle-mediated lung injury. J. Aerosol Sci. 29:553-560.
Gibson, H., Vincent, J. H. (1981) The penetration of dust through porous foam filter media. Ann. Occup. Hyg. Vol. 24, No. 2, pp. 205-215.
Greenough, G. K. (1979) Trials of the dust helmet in coal mines. The Mining Engineer. Vol. 138, pp. 559-565.
Hauck, B. C., Grinshpun, S. A., Reponen, A., Reponen, T., Willeke, K., Bornschein, R. L. (1997) Field testing of new aerosol sampling method with a porous curved surface as inlet. Americal Industrial Hygiene Association Journal Vol. 58, pp. 713-719.
Hinds, W. C. (1999): Aerosol Technology. New York; John Wiley and Sons, Inc.
Kenny, L. C., Aitken, R. J., Beaumont, G. and Görner, P. (2001) Investigation and application of a model for porous foam aerosol penetration. Journal of Aerosol Science Vol. 32, pp. 271-285.
International Commission on Radiological Protection (ICRP). (1994) Human respiratory tract model for radiological protection. ICRP publication 66. Ann. ICRP 24, Nos 1-3.
Oberdorster, G. (1995) The NTP talc inhalation study: a critical appraisal focused on lung particle overload. [Review] [27 refs]. Regulatory Toxicology & Pharmacology. 21(2):233-241.
Oberdorster, G. (2001) Pulmonary effects of inhaled ultrafine particles. Int Arch Occup Environ Health.74:1-8.
Oberdorster, G., Gelein, R. M., Ferin, J., Weiss, B. (1995) Association of particulate air pollution and acute mortality : involvement of ultrafine particles?. Inhalation Toxicology. 7:111-124.
Page, S. J., Volkwein, J. C., Baron, P. A., DeyeJ. (2000) Particulate penetration of porous foam used as a low flow rate respirable dust size classifier. Applied Occupational and Environmental Hygiene Vol. 15, No.7, pp.561-568.
Seaton, A., MacNee, W., Donaldson, K., Godden, D. (1995) Particulate air pollution and acute health effects. Lancet. 345:176-178.
Stahlhofen, W., Gebhart, L., Heyder, J. (1980) Experimental determination of the regional deposition of aerosol particles in the human respiratory tract. Am. Ind. Hyg. Assoc. J. 41:385-398a.
Vincent, J. H., Aitken, R. J., Mark, D. (1993) Porous plastic foam filtration media: penetration characteristics and applications in particle size-selective sampling. J. Aerosol Sci. Vol. 24, No. 7, pp. 929-944.
Vincent, J. H., Clement, C. F. (2000) Ultrafine particles in workplace atmospheres. Phil. Trans. R. Soc. Lond. A 358: 2673-2682.
Vincent, J. H., Ramachandran, G., Thomassen, Y., Keeler, G. J. (1999) Application of recent advances in aerosol sampling science towards the development of improved sampling devices: the way ahead. J. Environ. Monit. Vol. 1, pp. 285-292.
Wake, D., Brown, R.C., (1991) Filtration of monodisperse aerosols and polydisperse dusts by porous foam filters. J. Aerosol Sci. 22(6):693-706.
參考文獻(2)
Aitken, R. J., Vincent, J. H. and Mark, D. (1993) Application of porous foams as size selectors for biologically-relevant samplers. Appl. Occup. Envir. Hyg. Vol. 8, pp. 363-369.
Breum, N. O. (2000) The dust holding capacity of porous plastic foam used in particle size-selective sampling. J. Aerosol Sci. Vol. 31, No. 3, pp. 379-385.
Brown, R. C. (1980) Porous foam size selectors for respirable dust samplers. J. Aerosol Sci. Vol. 11, pp. 151-159.
Brown, R. C. (1984) A many-fibre model of airflow through a fibrous filter. J. Aerosol Sci. Vol. 15 , No. 5, pp. 583-593.
Chen, C. C., Lai, C. Y., Shih, T. S., Yeh, W. Y. (1998) Development of respirable aerosol samplers using porous foams. American Industrial Hygiene Association Journal Vol. 59, pp. 766-773.
Gibson, H., Vincent, J. H. (1981) The penetration of dust through porous foam filter media. Ann. Occup. Hyg. Vol. 24, No. 2, pp. 205-215.
Hinds, W. C. (1999): Aerosol Technology. New York; John Wiley and Sons, Inc.
Ingham, D. B., Heggs, P. J. and Hildyard, M. L. (1988) Technical note-a note on the pressure drop across a fibrous filter modeled as a symmetrical arry of cylinders. J. Aerosol Sci. Vol.10, No. 3, pp. 385-386.
Kenny, L. C., Aitken, R. J., Beaumont, G. and Görner, P. (2001) Investigation and application of a model for porous foam aerosol penetration. Journal of Aerosol Science Vol. 32, pp. 271-285.
Mark, D., Borzucki, G., Lynch, G. and Vincent, J. H. (1988) The development of a personal sampler for inspirable thoracic and respirable aerosol. Presented at the Annual Conference of the Aerosol Society, Bournemouth, U. K.
Vincent, J. H., Aitken, R. J., Mark, D. (1993) Porous plastic foam filtration media: penetration characteristics and applications in particle size-selective sampling. J. Aerosol Sci. Vol. 24, No. 7, pp. 929-944.
Wake, D., Brown, R.C., (1991) Filtration of monodisperse aerosols and polydisperse dusts by porous foam filters. J. Aerosol Sci. 22(6):693-706.
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