Investigation and Improvement of Ozone Emission from Ultraviolet Clean Equipment in a Color Filter Plant.
| Autor: | Ling-Yu kung, 孔令玉 |
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| Rok vydání: | 2007 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 95 Process of Color Filter (CF) sets high standard for the cleanness of Indium Tin Oxide (ITO) Glass. Glass is cleaned mainly by low pollution, highly efficient Ultraviolet (UV) equipment. UV equipment makes use of photosensitive oxidation of organic matter on glass surface by ultraviolet light. During cleaning process, photosensitive oxidation produces ozone toxic gas, which is diffused into the Clean Room when the glass comes out from reacting cabin of UV equipment, posing health hazard to the operators. The main purpose of this study is to examine the concentration distribution of emitted ozone in the work environment of UV equipment in a Color Filter plant. A fogger was used to visualize the direction of ozone-laden air flow. MDA toxic gas detector (Scientific ChemKey TLD-1, Zellweger Analytics, England) with chemical paper was used to measure the emitted ozone concentration at the breathing zone of operators and the exit of the UV equipment. MDA toxic gas detector output data every minute. In addition, the sampling and analysis method of (Occupational Safety & Health Administration) ID-214 was used to measure the 8-h time-weighted average ozone concentration and compared with those measured by the MDA detector. This study showed that the workers’ exposure concentrations measured by the MDA detector or OSHA ID214 all exceeded the current exposure 8-h time-weighted limit of ozone, or 100 ppb. The exit of UV equipment far exceeded this limit value. If the top covers of the carriers at the exit of two UV cleaning equipments were closed, then ozone was forced to discharge into the exhaust system of the reacting cabin of the UV cleaning equipment and diluted by the recirculation air of the clean room. Ozone concentration in the working area was found to reduce by 34%~64%, and ranged from 40~88 ppb. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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