(100.26.176.182) 您好!臺灣時間:2019/12/12 18:54
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果

詳目顯示:::

我願授權國圖
本論文永久網址: 
line
研究生:張倩瑜
研究生(外文):Chien-Yu Chang
論文名稱:微粒負載對熱脫附管效能影響以及前置濾材開發與評估
論文名稱(外文):The Effect of Aerosol Loading on the Performance of Thermal Desorption Tubes and the Development and Evaluation of a Pre-filter for Adsorption Tubes
指導教授:陳志傑陳志傑引用關係
口試委員:鄭福田林文印黃盛修蕭大智
口試日期:2016-01-08
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:2016
畢業學年度:104
語文別:中文
論文頁數:66
中文關鍵詞:採樣介質氣懸微粒微粒負載可替換式濾材
外文關鍵詞:Sampling devicesparticlesparticle loadingpre-filters
相關次數:
  • 被引用被引用:0
  • 點閱點閱:136
  • 評分評分:系統版面圖檔系統版面圖檔系統版面圖檔系統版面圖檔系統版面圖檔
  • 下載下載:0
  • 收藏至我的研究室書目清單書目收藏:0
近年來,熱脫附管被廣泛地應用於作業環境空氣中揮發性有機化合物的採樣。雖然市售熱脫附管在吸附劑前端通常以填充玻璃綿作為保護,但是,根據過去的實驗經驗得知,該段玻璃綿對微粒的收集效率並不高,這表示微粒仍會穿透玻璃綿進而沉積在吸附劑上。有鑑於此,本研究的目的在於,瞭解微粒負載對吸附劑吸附效能的影響,以及設計可替換式前置濾材以增加熱脫附管的使用壽命。
本研究自行填充熱脫附管進行測試,選用吸附劑為Carbopack X,填充重量為100 mg,測試流率為0.2 L/min。在吸附能力測試方面,使用丙酮進行評估,當達飽和時,隨即以氮氣進行脫附。在吸、脫附的過程中,以火焰離子偵測器進行即時濃度監測。研究中,分別以定量微粒輸出產生器 (TSI 3076) 與超音波霧化器 (Sono Tek) 分別產生次微米以下以及微米粒徑範圍的測試氣膠微粒,而在評估各式濾材或熱脫附管的微粒穿透率時,則分別搭配微粒電移動度掃描分徑器 (Scanning Mobility Particle Sizer, SMPS) 與氣動微粒分徑器 (Aerodynamic Particle Sizer, APS) 進行上、下游微粒粒徑濃度分布的量測;在微粒負載實驗時,熱脫附管則改用定量抽氣幫浦連續操作。微粒的材質有氯化鈉 (NaCl) 固體微粒與癸二酸二異辛酯 (DEHS) 液體微粒兩種。測試過程中,利用壓力轉換器來監測濾材壓降變化。所測試的前置濾材包括:原廠填充之玻璃綿、不鏽鋼篩網 (400、1500 Mesh)、海綿 (110 ppi) 以及N95等級之纖維性濾材。驗證前置濾材效能時,同時將兩支熱脫附管進行液態微粒負載,只是其中一支有加裝前置濾材;微粒負載後,再量測吸附效率曲線,並且分別與各自初始的曲線進行比較。
結果顯示,固態次微米與微米微粒負載重量為0.6 mg時,對吸附劑吸附能力的影響 (減少) 分別為5% 與13%。液態微粒同樣會降低吸附能力,且由於其會在吸附劑表面形成薄膜,大幅減少比表面積,所以影響較固態微粒明顯,當負載重量為0.8 mg時,差異為45%。原廠填充之玻璃綿的壓降為21.2 ± 8.1 mmH2O,最易穿透粒徑介於0.3 ~ 0.5 μm,其穿透率為60 ~ 75%。而400 Mesh的不鏽鋼篩網在表面風速為17 cm/s時,需要40層才能達到與玻璃綿有相當的過濾效率,但是所造成的空氣阻抗則約為32 mmH2O。增加篩網網目數至1500,同時配合降低表面風速至0.31 cm/s時 (篩網直徑約37 mm),則可以在較低的空氣阻抗下達到預期的過濾效率,但1500 Mesh篩網不容易取得,其成本也較高。另外,110 ppi海綿 (厚度30 mm) 在表面風速0.68 cm/s時,最易穿透粒徑 (約0.6 μm) 的效率約30% (空氣阻抗約0.25 mmH2O),因此如果要讓該海綿具有90% 的收集效率,則厚度需增加至約300 mm,雖然可透過壓縮來提高收集效率,但品質不易控管。N95等級纖維性濾材在表面風速為10.37 cm/s (直徑6.4 mm,厚度0.8 mm) 時,最易穿透粒徑 (約0.04 μm) 穿透率約5%,壓降為9.8 mmH2O,是目前唯一可以同時達到前置濾材所需具備之高效率、低阻抗、體積小、取得方便、價格便宜等特性的材料。最後,在液態微粒負載的情況下,加裝前置濾材 (N95等級之纖維性濾材) 可以大幅降低微粒負載對吸附劑吸附能力的影響程度。


Thermal desorption tubes are commonly used to quantify trace amount of VOCs in the workplace. Despite a small piece of glass wool normally placed in front of the sorbent, it is unlikely an absolute filter, and aerosol penetration and deposition on the sorbent are inevitable. Therefore, this study aimed to characterize the effect of aerosol loading on the performance of thermal desorption tubes. The ultimate goal was to design a pre-filter for a better performance of thermal desorption tubes in practical dusty working environments.
Homemade thermal desorption tubes loaded with 100 mg Carbopack X sorbents were used in the present study. The sampling flow rate was 0.2 L/min. Acetone vapor was generated to perform the adsorption tests and the nitrogen gas was used for desorption. A flame ionization detector (FID) was employed to measure the acetone concentrations upstream and downstream of the thermal desorption tubes. A constant output aerosol generator (TSI 3076) and an ultrasonic atomizing nozzle (Sono Tek) were used to generate sub-micrometer-sized and micrometer-sized aerosol particles, respectively. For aerosol penetration test, a scanning mobility particle sizer (TSI SMPS) and an aerodynamic particle sizer (TSI APS) were employed to measure the aerosol concentrations and size distributions upstream and downstream of the test filters. Both solid (NaCl) and liquid (DEHS) particles were generated and the pressure drop across the filter was simultaneously monitored. Glass wool plug, stainless steel mesh (#400, #1500), polyurethane foam (110 ppi) and fibrous filter disc cut from N95 filtering facepieces were tested in this work. Only the glass wool installed upstream of sorbent was tested for aerosol penetration. To verify the performance of the pre-filter, two thermal desorption tubes (one with the pre-filter) were simultaneously challenged with DEHS particles and then compared with the initial breakthrough curves.
The experimental results showed that the sub-micrometer-sized and micrometer-sized solid particle loading (loaded mass 0.6 mg) decreased the adsorption capacity, 5% and 13% less, respectively. The liquid particles could significantly deteriorate the sorption performance, because the deposited liquid particles might form the film covering the activate sites. The most penetrating particle size (MPPS) of the glass wool was 0.3 ~ 0.5 μm and the aerosol penetration of MPPS was about 60 ~ 75% with the pressure drop of 21.2 ± 8.1 mmH2O under the sampling flow of 0.2 L/min. As for the 400 mesh stainless steel, the aerosol penetration of 40 pieces was comparable to that of the glass wool with the face velocity of 17 cm/s and pressure drop of 32 mmH2O. High aerosol collection efficiency (for example, 90%) can be achieved by increasing the mesh number and decreasing the face velocity. However, the use of stainless steel with high mesh number (1500 mesh in this case) was not cost effective. With the use of 110-ppi foam, the total length of the foam was estimated to be as long as 300 mm to attain the required collection efficiency (90%) at a face velocity of 0.68 cm/s. The aerosol collection efficiency can be enhanced by increasing the foam packing density. However, it was difficult to guarantee the foam packing quality to gain reliable performance. Moreover, the N95 filter disc (D = 6.4 mm, H = 0.8 mm) showed an excellent performance on aerosol collection with a fairly low pressure drop of 9.8 mmH2O. Among the filter materials tested, the N95 filter disc worked best, for low cost, low pressure drop and stable quality. Finally, the devastating effect of aerosol loading on the adsorption performance of thermal desorption tubes can be significantly leveraged with the use of a N95 pre-filter.


目錄
致謝 I
摘要 II
Abstract IV
目錄 VI
圖目錄 IX
表目錄 X
第一章 前言 1
1.1 研究背景 1
1.2 研究目的 2
第二章 文獻探討 3
2.1 揮發性有機物特性與危害 3
2.2 揮發性有機物採樣方法 3
2.3 吸附劑種類與特性 4
2.3.1 石墨化碳黑吸附劑 5
2.3.2 Tenax 吸附劑 5
2.4影響吸附劑吸附效能的因子 6
2.4.1 溫度 6
2.4.2 濕度 6
2.4.3 揮發性有機化合物之濃度 7
2.4.4 揮發性有機化合物之種類 7
2.4.5 氣體流率 7
2.4.6 吸附劑本身之變異性與填充結構 8
2.4.7 微粒負載 8
2.5 氣懸微粒過濾機制 9
2.6 濾材過濾之壓降 12
2.7 濾材之過濾品質 13
2.8 濾材之種類與過濾特性 13
2.8.1 編織性濾材 14
2.8.2 纖維性濾材 15
2.8.3 薄膜濾材 17
2.8.4 顆粒狀濾材 18
2.8.5 海綿 19
2.9 可替換式前置濾材之特性 21
第三章 研究系統與操作方法 23
3.1 市售熱脫附管填充構造 23
3.2 熱脫附管填充系統 23
3.3 熱脫附管吸、脫附效率曲線量測系統 24
3.4 微粒負載系統 26
3.5 市售熱脫附管內玻璃綿之取得 27
3.6 微粒穿透率量測系統 27
3.7前置濾材驗證系統 29
第四章 結果與討論 30
4.1 自製熱脫附管之微粒穿透率 30
4.2 微粒負載對吸附效能曲線之影響 30
4.3市售熱脫附管內玻璃綿之收集效率 32
4.4前置濾材之收集效率 33
4.4.1不鏽鋼篩網 33
4.4.2海綿 35
4.4.3 N95等級之纖維性濾材 35
4.5前置濾材握持器之設計 36
4.6 前置濾材效能驗證 37
第五章 結論與建議 38
參考文獻 40

圖目錄
圖1、市售熱脫附管填充構造 46
圖2、(a) 自製Carbopack X熱脫附管之填充構造;(b) 熱脫附管填充系統 47
圖3、吸、脫附效率曲線量測系統 48
圖4、(a) 固、液態次微米微粒負載系統;(b) 固態微米微粒負載系統 49
圖5、微粒穿透率量測系統 50
圖6、前置濾材驗證系統 51
圖7、自製Carbopack X熱脫附管之微粒穿透率曲線 52
圖8、固態次微米微粒對Carbopack X吸附劑吸附效率曲線之影響 53
圖9、固態微米微粒對Carbopack X吸附劑吸附效率曲線之影響 54
圖10、液態次微米微粒對Carbopack X吸附劑吸附效率曲線之影響 55
圖11、微粒負載重量與Carbopack X吸附劑50% 破出時間減少比例之關係 56
圖12、微粒負載過程中熱脫附管壓降隨時間變化情形 57
圖13、市售熱脫附管內玻璃綿之微粒穿透率曲線 58
圖14、10片400 Mesh不鏽鋼篩網之微粒穿透率曲線 59
圖15、1500 Mesh不鏽鋼篩網之微粒穿透率曲線 (表面風速17 cm/s) 60
圖16、1500 Mesh不鏽鋼篩網之微粒穿透率曲線 (表面風速 0.31 cm/s) 61
圖17、海綿之微粒穿透率曲線 62
圖18、N95 等級纖維式濾材之微粒穿透率曲線 63
圖19、前置濾材達90% 收集效率時之設計構型 64
圖20、前置濾材握持器之組裝示意圖 65
圖21、以丙酮氣體驗證前置濾材效能之結果 66

表目錄
表 1、濾材微粒穿透率測試之參數表 44
表 2、前置濾材的測試條件以及達90% 收集效率時之設計參數 45




1. Bruno, P., Caputi, M., Caselli, M., De Gennaro, G., De Rienzo, M. (2005). Reliability of a BTEX radial diffusive sampler for thermal desorption: field measurements. Atmospheric Environment 39:1347-1355.
2. Chen, C.-C., Chen, W.-Y., Huang, S.-H., Lin, W.-Y., Kuo, Y.-M., Jeng, F.-T. (2001). Experimental study on the loading characteristics of needlefelt filters with micrometer-sized monodisperse aerosols. Aerosol Science & Technology 34:262-273.
3. Chen, C.-C. and Huang, S.-H. (1998). The effects of particle charge on the performance of a filtering facepiece. American Industrial Hygiene Association 59:227-233.
4. EPA, U. Volatile Organic Compounds (VOCs).
5. Gilian GilAir Plus Brochure - Sensidyne.
6. Harper, M. (2000). Sorbent trapping of volatile organic compounds from air. Journal of Chromatography A 885:129-151.
7. Hinds, W. C. (1982). Aerosol technology: properties, behavior, and measurement of airborne particles. New York, Wiley-Interscience, 1982. 442 p. 1.
8. Huang, S.-H., Chen, C.-W., Chang, C.-P., Lai, C.-Y., Chen, C.-C. (2007). Penetration of 4.5 nm to aerosol particles through fibrous filters. Journal of Aerosol Science 38:719-727.
9. Jaroszczyk, T., Liu, Z. G., Schwartz, S. W., Holm, C. E., Badeau, K. M., Janikowski, E. (2002). Direct flow air filters - a new approach to high performance engine filtration, in FILTECH, Wiesbaden, 234 - 244.
10. Kim, C. S., Bao, L., Okuyama, K., Shimada, M., Niinuma, H. (2006). Filtration efficiency of a fibrous filter for nanoparticles. Journal of Nanoparticle Research 8:215-221.
11. Król, S., Zabiegała, B., Namieśnik, J. (2010). Monitoring VOCs in atmospheric air II. Sample collection and preparation. TrAC Trends in Analytical Chemistry 29:1101-1112.
12. Krost, K. J., Pellizzari, E. D., Walburn, S. G., Hubbard, S. A. (1982). Collection and analysis of hazardous organic emissions. Analytical Chemistry 54:810-817.
13. Kulkarni, P., Baron, P. A., Willeke, K. (2011). Aerosol measurement: principles, techniques, and applications. John Wiley & Sons.
14. Kumar, A. and Víden, I. (2007). Volatile organic compounds: Sampling methods and their worldwide profile in ambient air. Environmental Monitoring and Assessment 131:301-321.
15. Kuo, Y.-M., Huang, S.-H., Lin, W.-Y., Hsiao, M.-F., Chen, C.-C. (2010). Filtration and loading characteristics of granular bed filters. Journal of Aerosol Science 41:223-229.
16. Kuo, Y.-M., Huang, S.-H., Shih, T.-S., Chen, C.-C., Weng, Y.-M., Lin, W.-Y. (2005). Development of a size-selective inlet-simulating ICRP lung deposition fraction. Aerosol Science and Technology 39:437-443.
17. Kuo, Y.-M., Lin, C.-W., Huang, S.-H., Chang, K.-N., Chen, C.-C. (2013). Effect of aerosol loading on breakthrough characteristics of activated charcoal cartridges. Journal of Aerosol Science 55:57-65.
18. Leung, W. W.-F., Hung, C.-H., Yuen, P.-T. (2010). Effect of face velocity, nanofiber packing density and thickness on filtration performance of filters with nanofibers coated on a substrate. Separation and Purification Technology 71:30-37.
19. MacLeod, G. and Ames, J. M. (1986). Comparative assessment of the artefact background on thermal desorption of Tenax GC and Tenax TA. Journal of Chromatography A 355:393-398.
20. Miguel, A. F. (2003). Effect of air humidity on the evolution of permeability and performance of a fibrous filter during loading with hygroscopic and non-hygroscopic particles. Journal of Aerosol Science 34:783-799.
21. Nelson, G. O., Correia, A. N., Harder, C. A. (1976). Respirator cartridge efficiency studies: VII. Effect of relative humidity and temperature. The American Industrial Hygiene Association Journal 37:280-288.
22. Nelson, G. O. and Harder, C. A. (1972). Respirator cartridge efficiency studies IV. Effects of steady-state and pulsating flow. The American Industrial Hygiene Association Journal 33:797-805.
23. Podgórski, A., Bałazy, A., Gradoń, L. (2006). Application of nanofibers to improve the filtration efficiency of the most penetrating aerosol particles in fibrous filters. Chemical Engineering Science 61:6804-6815.
24. Supelco Adsorbent Selection Guide.
25. Supelco Graphitized Carbon Black (GCB).
26. Swearengen, P. and Weaver, S. (1988). Respirator cartridge study using organic-vapor mixtures. The American Industrial Hygiene Association Journal 49:70-74.
27. Tanaka, S., Nakano, Y., Tsunemori, K., Shimada, M., Seki, Y. (1999). A study on the relative breakthrough time (RBT) of a respirator cartridge for forty-six kinds of organic solvent vapors. Applied Occupational and Environmental Hygiene 14:691-695.
28. Trout, D., Breysse, P., Hall, T., Corn, M., Risby, T. (1986). Determination of organic vapor respirator cartridge variability in terms of degree of activation of the carbon and cartridge packing density. The American Industrial Hygiene Association Journal 47:491-496.
29. USA, F. I. I. Foamex International Inc. USA.
30. Wang, C.-S. (2001). Electrostatic forces in fibrous filters—a review. Powder Technology 118:166-170.
31. 台灣環保署 揮發性有機物空氣汙染管制及排放標準.
32. 行政院勞工委員會 (1997). 化學性因子作業環境測定教材.
33. 吳季融 (2003). 空氣中有機汙染物自動分析技術之開發研究:壹、碳沸石多重床與中孔徑細沸石之氣體吸附性研究;貳、有機汙染物垂直探空光化研究, 國立中央大學.
34. 呂博弘 (2003). 聚胺酯海綿之微粒負載特性, in 職業醫學與工業衛生研究所, 國立台灣大學.
35. 林志威 (2005). 影響活性碳濾毒罐效能因子評估研究, in 職業醫學與工業衛生研究所, 國立台灣大學.
36. 詹煜銘 (2006). 奈米微粒於薄膜過濾下之負載特性研究, in 環境工程學研究所, 國立台灣大學.


QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top
無相關論文
 
無相關期刊
 
無相關點閱論文
 
系統版面圖檔 系統版面圖檔