一個員工餐廳的靜電除油煙機的控制效率

Abstract

新竹科學工業園區內廠商多設有員工餐廳，餐廳經由烹飪排放之廢氣若未能有效處理而逕行排放，可能經由外氣空調箱流竄進入鄰近高科技廠房之無塵室。本研究對象為園區內某員工餐廳的廚房，探討靜電除油煙機對廚房排放的油煙的去除效率。本研究的實驗分為兩階段，第一階段利用粉塵質量濃度即時監測儀TSI DustTrak於排放管道監測PM1.0，探討靜電除油煙機之效率及污染改善成效。第二階段實驗使用Marple個人多階衝擊器，測量油煙的質量濃度分佈，並與DustTrak的PM2.5監測結果作比較。 第一階段實驗(97/04/20~97/08/30)使用DustTrak在靜電機二次保養週期（每次保養週期為二個月左右）間監測，結果發現靜電除油煙機的PM1.0去除效率隨運作時間由剛保養完的97%降至保養前的63%。靜電除油煙機關閉時，油煙排放平均PM1.0質量濃度落於6.5~18.8mg/m3之間；當靜電除油煙機開啟時，油煙排放平均PM1.0質量濃度落於0.3~3.1mg/m3之間。裝設廚房油煙防制設備前的油煙PM1.0年排放量約為513kg，裝設防制設備後年排放量約為63kg，油煙廢氣年PM1.0排放量約可減少450kg，結果顯示污染改善有效。 第二階段的實驗結果發現廚房油煙以小顆粒微粒為主，其中粒徑在0.1 μm以下所占質量比例最多，約為26.3~37%，而10 μm以下之微粒所占的比例約為64.4~68.6%。比對DustTrak與Marple impactor 的結果發現，前者的PM2.5濃度比後者高很多，主要是因DustTrak的校正是以粗微粒為之的緣故。

Most companies located in the Hsinchu Science Park are equipped with the staff dining room. If not properly treated, the waste gas emitted from the kitchen can enter the clean rooms of the neighboring high-tech fabs through the air handling units. The experiment in this study has two stages. In the stage 1, a TSI DustTrak was used to monitor PM1.0 in the exhaust duct, and determine the control efficiency of the oil smoke and the effectiveness of the pollution reduction. In the second stage, a Marple personal cascade impactor was used to measure the mass distribution of the oil smoke, and the PM2.5 concentrations were compared with thosed monitored by the TSI DustTrak. The first stage experiment (97/04/20~97/08/30) used the TSI DustTrak to monitor the oil smoke emission during the two preventive maintenance cycles (PM), each lasted for about 2 months. Experimental results showethat the control efficiency for PM1.0 is as high as 97% after the PM and falles to 63% at the end of the PM cycles. When the ESP was turned off, the average PM1.0 mass concentration ranged between 6.5~18.8 mg/m3. When the ESP was turned on, the averaged PM1.0 mass concentration ranged between 0.3~3.1mg/m3. The total yearly mass emission was approximately 513 kg before the ESP was installed. After the ESP was installed, the yearly emission was reduced to 62 kg, or 451 kg reduction. That is, the installation of the control device is effective for pollution reduction. Experimental results in the second stage show that the oil smoke mainly contains small particles, in which the mass fraction of the particles below 0.1 μm, which ranges from 26.3~37%, is the most predominant.The mass fraction of PM10 ranges from 64.4~68.6%.Comparing the results of the DustTrak and Marple impactor, it is found that PM2.5 concentration of the former is much higher than the latter. This is due to the fact that coarse particles are used in the calibration of the DustTrak.