整合高壓不鏽鋼靜電濾網於市售油霧濾材以提升效能之研究

Study on the high-voltage stainless steel mesh filter for the improvement of commercial oil mist filters

高巧欣(Qiao-Xin Gao)

指導教授 ： 李世光

共同指導教授 ： 吳光鐘 ； 許聿翔(Yu-Hsiang Hsu)

國立臺灣大學/工學院/應用力學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201903811

摘要

根據《世界衛生組織》2014年的統計指出，全球室內污染人口主要分佈於亞洲及非洲區域，約有 30 億人。因欠缺通風及過濾系統的廚房，其烹調所產生的煙霧，將導致每年約 350 至 430 萬人喪命。由TEDS (Taiwan Emission Data System) 9.0可知台灣在餐廳及家庭使用排放上，各占PM2.5總排放量中的6.39％ 及17.13％。因此如何有效的防止吸入油霧，已成為世界各國主要研究的目標之一。
在此研究中針對濾材過濾油霧時，過濾效能明顯下降的議題進行討論並提出解決方式。因市售聚丙烯靜電濾材在過濾中擁有靜電吸引的機制，因此其在過濾微粒粒徑為100至400 奈米間時有較高的過濾效率，然而，聚丙烯靜電濾材在過濾油霧時，其帶電性將隨之下降，進而導致過濾效率降低，因此，將市售聚丙烯靜電濾材進行表面改質，於其表面噴灑奈米顆粒，發現噴灑聚四氟乙烯奈米顆粒於聚丙烯靜電濾材上，能夠有效延緩聚丙烯靜電濾材於高油霧環境下，帶電性耗損程度的趨勢，使其過濾膜品質提升23.25 %。
此外，利用不銹鋼濾網施加電場於市售油霧濾材間進行油霧過濾，發現不鏽鋼濾網第一層接正電、第二層接地與第三層接正電時所產生之電場，能夠使整體過濾效率提高2.47 %。也針對不鏽鋼濾網間市售濾材排列順序做了研究，發現若濾材排列順序依序為親油濾材及疏油濾材時，其過濾效率將表現最好。若在親油濾材及疏油濾材前添熱塑性聚氨酯防油層，則可發現其能夠使整體系統壓損上升幅度減少27.36 %、過濾效率提升2.72 %。而在長時間過濾油霧下，施加電場則能夠使整體過濾效能變好。因此，可得知在不鏽鋼濾網第一層接正電、第二層接地與第三層接正電時所產生之電場下，濾材排列順序為熱塑性聚氨酯防油層、親油濾材及疏油濾材時，過濾油霧之效能最好。

關鍵字

油霧 ； 靜電濾材 ； PTFE奈米顆粒 ； 不銹鋼濾網 ； 電場 ； 熱塑性聚氨酯 ； 過濾效率

並列摘要

According to the global report of the World Health Organization in 2014, the global population affected by indoor pollution is mainly in Asia and Africa, and it influences about 3 billion people. Due to the lack of ventilation and filtration systems, oil mist generated by cooking kills about 3.5 to 4.3 million people every year. According to TEDS(Taiwan Emission Data System) 9.0, Taiwan's emissions from restaurants and households account for 6.39% and 17.13% of the total PM2.5 (PM: Particulate matter) emissions. Therefore, how to effectively prevent the inhalation of oil mist become one of the main tasks in the world.
In this study, methods to enhance commercial oil-mist filters are proposed and studied. Since the commercial polypropylene (PP) electrostatic filter provides filtration mechanism of electrostatic attraction, it has a higher filtration efficiency for the particle size between 100 to 400 nm. However, captured oil mist can mask PP fibers, and the chargeability and its filtration efficiency can be depleted very quickly. Therefore, a method to modify the surface of PP fibers is developed in this thesis. Nanoparticles are sprayed on the surface of PP fibers to change its surface energy. It was found that spraying PTFE (polytetrafluoroethene) nanoparticles on PP fibers can improve the filtration efficiency and achieve 23.25 % higher performance.
Secondly, electric field was introduced to commercial filter by using stainless steel meshes to sandwich these filters. Commercial filters are placed between two stainless steel meshes. It was found that letting the front stainless steel mesh to be positively charged and grounded the other one on the back, the quality factor is 6.46 times higher than no charged stainless steel meshes. It also was found that placing commercial filters sequentially as oleophilic filter at front followed by putting a oleophobic filter behind it can have a better filtration efficiency by 2.47 %. Finally, by placing a high porous TPU (thermoplastic polyurethane) filter in front of all commercial filters, the overall pressure drop can be significantly decreased by 27.36 % and the filtration efficiency can increased by 2.72 %. This design can prolong the usage of commercial filters for oil mist filtrations and also decrease the system pressure drop.

並列關鍵字

oil mist ； electrostatic filter ； PTFE nanoparticles ； stainless steel filter ； electric field ； thermoplastic polyurethane ； the filtration efficiency

參考文獻

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