奈米光觸媒應用於空調系統分解甲醛之研究

Research on Decomposition of Formaldehyde by Nanocatalyst in the Air Conditioning System

何信志(Shin-Jr Ho)

指導教授 ： 卓清松

國立臺北科技大學/機電學院/能源與冷凍空調工程系碩士班/碩士(2007年)

摘要

近年來人們對於居住環境空氣品質需求日趨重視，傳統空調設備多以增加外氣方式解決此一問題。增加外氣供給量雖能稀釋室內的污染物，但是卻會造成能源消耗量的增加。為了解決此一問題，利用光觸媒的空氣清淨裝置來降低污染物濃度，能減少外氣換氣量，達到節能與空氣品質兼顧的目的。
本研究將以一套封閉可變溫濕度的氣體循環空調箱中，安裝紫外光/二氧化鈦濾網(UV/TiO2 Filters)反應器，針對有機污染物-甲醛，探討室內溫度、濕度、循環風速為操作參數，對於空調設備系統中光催化分解污染物甲醛效率之影響。研究結果顯示，光催化甲醛對於反應溫度效應方面，隨著溫度提高光催化愈佳，經過120分鐘的光分解測試後，可將甲醛濃度去除率達至85.97%；反應濕度效應方面，則隨濕度增加使觸媒表面水分增加進而增進甲醛氣體分解，其去除率可達至89.02%；當污染物與光觸媒接觸分解時間充足，則循環風速愈大，循環次數愈高，光催化效能愈佳，甲醛濃度去除效能為85.85%。利用本研究可得降低室內污染物與清淨室內空氣及減少空調設備引進外氣負荷量，且具有節能及提升人體健康的效益。

關鍵字

二氧化鈦 ； 甲醛 ； 空氣品質

並列摘要

People have been putting more focus on the air quality of their environment within recent years, and the traditional solution in light of this issue is to apply external gas method to their air-conditioning equipment. Although the adding of external gas can indeed dilute indoor pollutants, it leads to the increase of energy consumption. In order to solve this problem, air cleaning system with photocatalyst is used to reduce the concentration of the pollutants, which further decrease the ventilation volume of external gas and reaching the purposes of both power saving and good air quality.
This study installs UV/TiO2 Filters reactor into a set of enclosed gas circulation air-conditioning box with changeable temperature and humidity, and based on the organic pollutant formaldehyde, as well as taking indoor temperature, humidity, circulation wind velocity as working parameters, it investigates into the effect and efficiency of the photocatalytic function of the air-conditioning equipment system in diluting the pollutant of formaldehyde. Research result shows that, in the aspect of the photocatalysis of formaldehyde reacting to the temperature, increase in temperature can enhance the performance of photocatalysis. After 120 minutes of photocatalysis test, the removal rate of formaldehyde concentration reaches 85.97%. In the aspect of reacting to the humidity, the increase of humidity will increase the surface vapor of the photocatalyst, improving the performance of formaldehyde gas dilution, and reaching the removal rate of 89.02%. When the pollutants have sufficient time to contact the photocatalyst for further dilution, the greater the circulation wind velocity, the higher the circulation frequency, the better the efficiency of photocatalysis, and the removal rate of formaldehyde reaches 85.85%. This study can reduce the indoor pollutants, ventilate indoor gas and reduce the loading volume induced by air-conditioning equipment. It further carries the benefits of power saving and improvement of human physical health.

並列關鍵字

TiO2 ； formaldehyde ； Indoor Air Quality

參考文獻

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