應用CALPUFF模式模擬砷空氣污染物在新竹科學園區的分佈及趨勢

Abstract

在新竹科學園區中，半導體業以及光電業的工廠在其產品製造的過程中常需要添加許多化學物質，其中就有包括砷此化學物質.因此造成了在工廠的排放廢氣中含有砷及其他砷化合物的有毒物質，且在2005年工研院的一篇發表期刊中“ Evaluation of arsenical emission from semiconductor and opto-electronics facilities in Hsinchu, Taiwan”，發現在新竹科學園區中，檢測空氣中砷化物的含量，發現在園區四周環境砷濃度的檢測，皆有大幅超過美國健康風險值評估所建議的標準量！對於居住在附近的居民將會有高度的致癌風險狀況，以及其他對人體傷害的危機。然而現在環保署空氣污染物的法規中，尚無對砷的空氣污染物有確切的法令。 研究中，將採用CALPUFF大氣空氣品質污染模式，模擬在新竹科學園區及新竹市的砷空氣污染物在濃度排放趨勢以及濃度累積的特徵分析。在本研究中在新竹科學園區模擬部份是採用SLUG煙流模式，再加以簡單地形效應以及複雜地形應分成兩案例做分析；在新竹市的模擬部份則採用PUFF煙陣模式再加以簡單地形效應以及複雜地形應分成兩案例做分析，總共做了四個案例的模擬。在新竹科學園區模擬的結果顯示，模擬出的濃度結果遠低於周界環境真實測出的砷濃度值，因此推測可能是因為煙囪排放量資料不足造成此現象。在新竹市模擬結果顯示，白天的高濃度累積區域都在科學園區煙囪位置附近，但到了晚上六點之後高濃度累積開始往科學園區的西南移動，高濃度累積區域開始往西南方向擴大，最高濃度位置也開始離開新竹科學園區，因此推測砷空氣污染物不只會在園區內累積，也會影響到新竹其他區域。在最後，研究中使用同樣的排放量做了2002年一年的砷污染物擴散影響的區域狀況，得知2002年砷年濃度平均量為5.68E-06(μgm-3)，且一年中秋、冬、春天的污染物擴散行為都是由煙囪排放源往西南方向為主，此範圍多是在新竹市香山區、竹南鎮及寶山鄉的交界。污染物也有擴散至新竹市香山區北邊狀況，但是較少且濃度值與西南方向擴散情況比較也是較低的。夏天則會因為風向的改變，擴散影響範圍改變，變成從排放源擴散至東邊及東北邊居多，此區域為新竹市東區以及竹北市靠近東區交界的區塊，也有些許擴散狀況是至新竹科學園區排放源西北方的香山區以及東區。2002年中每月平均最高濃度值與發生位置皆是在新竹科學園區附近，冬天每月平均最高濃度值整體而言較秋天及春天、夏天高，春夏的每月平均最高濃度值是季節中最低的。

Arsenics compounds and arsine are used in Semiconductor and opto-electronics industries and are usually used in manufacturing processes. Then, the process vent stream of industries contains toxic arsine and other arsenic compounds. The ambient concentration of particulate arsenic was measured by this paper is named of “ Evaluation of arsenical emission from semiconductor and opto-electronics facilities in Hsinchu, Taiwan”. It dedicates that the ambient concentration of arsenic particulate in Science Based Industrial Park, Hsinchu, Taiwan was exceed the ambient air level goal (AALG) of arsenic compound performed by the US EPA. It will be hazardous to the residents. Moreover, there is still no available Laws and regulations for arsenic pollution in Taiwan. Therefore, in this study will use CALPUFF air pollution model to simulate the arsenic pollutant emission trends and concentration performance in Science Based Industrial Park in Hsinchu and Hsinchu city.The simulation of Science Based Industrial Park will use slug plume model with simple and complex terrian effects. Hsinchu city is use puff model with simple and complex terrian effects to simulate. The Simulated result of Science Based Industrial Park find that，the simulate concentration is more lower than real ambient concentration in Science Based Industrial Park, Hsinchu. It may probably because of insufficient emission rate data from the source information caused this phenomenon. Simulation results show that in Hsinchu City, the high concentration area is all nearby the stack of the Science Based Industrial Park in day time, but the high concentration area is will move to the southwest direction from Science Based Industrial Park after 6:00 pm. And the high concentration area is becoming bigger, the highest concentration position began to leave the Science Based Industrial Park area. Speculated that arsenic particle is not only accumulate in the park, and will also accumulate in other regions of Hsinchu. In the end, the study using the same emission of arsenic in the year 2002, the regional conditions affect the dispersion of pollutants, that in 2002 the average amount of arsenic in the concentration of 5.68E-06 (μgm-3), and the year of the Mid-Autumn , winter, spring, diffusion of pollutants are discharged from the chimneys to the southwest of the main sources, this range is more Hsinchu Xiangshan District, Junan Town, and Baoshan Township border. Pollutants have spread to the north of Hsinchu Xiangshan District, the situation but less and concentration compared with the southwest is lower.Because the wind will change, proliferation of the extent of change, to become spread from the source to the east and northeast side of the majority, this region and for the East District, Hsinchu City near the Eastern border Jhubei block, also slightly spread position is to the Hsinchu Science Park source Xiangshan District, north-west and the Eastern. In 2002 the average monthly value of the maximum concentration of location and the occurrence of both in the Hsinchu Science Park, near the highest concentration of winter, the average monthly value of the whole, than the fall and spring, high summer, spring and summer the monthly average maximum concentration value of season the lowest.