空氣負離子對室內懸浮微粒去除效率之研究

Removal of indoor suspended particulate by negative air ion

鄭博仁(Po-Jen Cheng)

指導教授 ： 李慧梅

國立臺灣大學/工學院/環境工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00914

摘要

目前已知懸浮微粒(suspended particulate)為室內空氣污染物的主要物種之一，而室內懸浮微粒的控制技術一般可分成過濾去除與靜電去除二類。本研究之目的即在評估靜電技術中的空氣負離子（Negative air ion , NAI）對懸浮微粒之去除效果。
NAI為一種帶有電荷，低污染性的物質，本研究利用電極放電的原理來產生實驗所需的NAI（3000∼5000 ions/cm3）。本研究以NaCl為氣膠物種，選取0.3μm與0.03μm二種粒徑分別注入不

關鍵字

Qi ； 再揚起程度 ； T50 ； 空氣負離子 ； 懸浮微粒

並列摘要

The suspended particulate is one of the main indoor air pollutants. Generally, the removal methods of the suspended particulate can be classified to filtration and electrostatic collection technologies. The negative air ion (NAI) is a kind of low pollution material with electric charge. The purpose of this work is evaluating the NAI for removal of indoor suspended particulate.

In this work, we used corona discharge to produce NAI (3000-5000 ions/cm3). Two sizes (0.3 and 0.03 μm) of NaCl were selected as the test aerosol to inject into the chamber which was manufactured form stainless steel to imitate indoor environment. We select four kinds of common indoor building materials (timber, wallpaper, of plastics, cement paint) to adhere to the surface of the wall inside the chamber. Four index was used to illustrate the characteristics of the particle removed by NAI, including removal efficiency, T50 (the half-life of particle concentration), Qi (the net efficiency of negative air ion) and reentrainment.

The results showed that when the NAI was turned off, the 0.3 μm-particle removal efficiency of the plastics (26%) is highest and that of the stainless steel (10.2%) is lowest. For 0.03 μm-particle, the removal efficiency of cement paint (46.2%) and plastics (40.3%) are better than that of others, as well as that of the stainless steel (25.6%) is the lowest. While the NAI was turned on, the 0.3μm-particle removal efficiency of the plastics (68.2%) is largest, and that of the stainless steel (44.4%) is smallest. With 0.03μm particle, the removal efficiency of the timber(82.5%) is highest and that of the stainless steel (59.6%) is lowest.

The results showed that when the NAI was turned off, the 0.3μm-particle T50 of
the wallpaper(70.7 mins) is shortest, and that of the stainless steel(192.5 mins) is longest. For 0.03μm-particle, the T50 of the cement paint(33.6 mins) is shortest, and that of the stainless steel(67.3 mins) is longest. While the NAI was turned on, the 0.3μm-particle T50 of the timber(16.5 mins) is shortest, as well as that of the stainless steel (34 mins) is longest. For 0.03μm particle, the T50 of the timber(12 mins) is smallest and that of the stainless steel (22.4 mins) is longest.

As regard the Qi of 0.3μm particle, the Qi of the timber(34.7 Lpm) is largest and that of the cement paint(14 Lpm) is smallest. For 0.03μm particle, the Qi of the timber(41.9 Lpm) is highest, as well as that of the stainless steel(20.5 Lpm) is lowest.
Regard to reentrainment, the reentrainment of 0.3μm-particle was only observed of the wallpaper, and the level of the reentrainment is about 2.6%. The reentrainment of 0.03μm-particle was observed of the stainless steel, cement paint and wallpaper and the level of the reentrainment of them are 6.6%, 4.6% and 3.6%.

The result of this study shows that the material of timber has the best removal efficiency while NAI was turned on, and that of the stainless steel has the lowest removal efficiency. As regard the size of particles, the removal efficiency of 0.03μm- particle is better than that of 0.3μm-particle while we turn on the NAI. Regard to T50, the T50 of 0.03 μm-particle is shortest than that of 0.3μm-particle and that of the timber is shortest, as well as that of the stainless steel is longest. As regard the reentrainment, the level of the reentrainment of 0.03μm particle is more obvious than 0.3μm.

並列關鍵字

Reentrainment ； T50 ； negative air ion( NAI) ； Suspended particulate ； Qi

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