The influence of surface characteristics of indoor materials on the removal efficiency of suspended particles with the aid of negative air ion
Date Issued
2006
Date
2006
Author(s)
Sun, Haw-Jen
DOI
zh-TW
Abstract
目前已知懸浮微粒為室內空氣主要污染物之一，而其控制技術一般可分為過濾移除與靜電去除兩類。本研究的目的為評估在不同的室內材質表面下，材質表面特性對使用空氣負離子（Negative Air Ion, NAI）去除懸浮微粒效率的影響。
NAI為一種帶有電荷，低污染性的物質，本研究利用針尖放電的原理來產生實驗所需的NAI（300000∼500000 ions/cm3）。本研究以硬酯酸為氣膠物種，選取0.3μm與0.03μm二種粒徑分別注入不銹鋼製成的環境模擬箱中進行實驗，再選取七種常見的室內表面材質（三種木材材質（夾板、貼皮、亮面板）、三種塑膠材質（PVC、PP、PE）和橡膠，貼附於模擬箱內壁進行室內環境模擬，探討表面粗糙度和介電常數對ECR值的影響。
在材質表面粗糙度部分，以三種木類材質做比較，其平均表面粗糙度（μm）分別為夾板材質（2.52∼N. D.）、貼皮材質（2.36∼4.67）、亮面材質（0.27∼0.48）。在0.03 μm的情況下，三類木材的ECR分別為夾板材質（158 Lpm）、貼皮材質（140 Lpm）、亮面材質（106 Lpm）；而在0.3 μm的情況下，三類木材的ECR分別為木材夾板材質（124 Lpm）、木材貼皮材質（71.7 Lpm）、木材亮面材質（79.9 Lpm）。
在材質介電常數部份，以三種塑膠類材質做比較，其介電常數分別為PVC（2.61∼2.66）、PE（2.26∼2.28）、PP（2.11∼2.13），在0.03 μm的情況下，三類塑膠材質的ECR分別為PVC材質（329 Lpm）、PE材質（361 Lpm）、PP材質（224 Lpm）；而在0.3 μm的情況下，三種塑膠材質的ECR分別為PVC材質（245 Lpm）、PE材質（217 Lpm）、PP材質（184 Lpm）。
實驗結果中，材質部分以三種塑膠材質的效果最佳，不銹鋼最差。在粒徑部分，空氣負離子對0.03μm的去除效率大於0.3μm。T50部分則是以粒徑0.03μm較0.3μm快，其中又以塑膠類的T50最短，不銹鋼最長。
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 purpose of this work is evaluating that under different indoor textures, how the surface characteristics influence the removal efficiency of indoor suspended particulate with aids of NAI.
In this work, we used negative electric discharge to produce NAI (300000-500000 ions/cm3). Two sizes (0.3 and 0.03 μm) of Stearic acid were selected as the test aerosol to inject into the chamber which was manufactured form stainless steel to imitate indoor environment. We select seven kinds of common indoor materials (three kinds of wood, three kinds of plastics, and rubber) to adhere to the surface of the wall inside the chamber, and evaluate that how dielectric constant and surface roughness influence the ECR value.
Regard to texture surface roughness, we compare of three kinds of wood materials, its surface roughness (μm) for splint material is 2.52 – N. D., for stick to leather material is 2.36 - 4.6, and for bright surface material is 0.27 - 0.4 on average. In case of 0.03 μm, the ECR for three kind of wood for splint material is 158 Lpm, for stick to leather material is 140 Lpm, for bright surface material is 106 Lpm; In case of 0.3 μm, the ECR for three kinds of wood for splint material is 124 Lpm, for stick to leather material is 71.7 Lpm , and for bright surface material is 79.9 Lpm, respectively.
As regard to material dielectric constant, we compare three kinds of plastics materials, its dielectric constant are 2.61 - 2.6 for PVC, 2.26 - 2.2 for PE, and 2.11 - 2.1 for PP. In case of 0.03 μm, the ECR of three kinds of plastic materials are329 Lpm for PVC material, 361 Lpm for PE material, 224 Lpm for PP material. In case of 0.3 μm, the ECR of three kinds of plastic materials is 245 Lpm for PVC, 217 Lpm for PE, 184 Lpm for PP.
The experimental result shows that the three kinds of plastic materials have the best removal efficiency with aid of NAI, while the stainless steel has the lowest one. As regard the particle diameter, the removal efficiency of 0.03 μm-particle is better than that of 0.3 μm-particle with the aid of NAI. Regard to T50, the T50 of 0.03 μm -particle is shortest than that of 0.3μm-particle and that of the three plastic material is shortest, as well as that of the stainless steel is longest.
Subjects
懸浮微粒
空氣負離子(NAI)
T50
ECR
Suspended particulate
negative air ion( NAI)
SDGs
Type
thesis
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