近年來光電產業發展迅速,由於製程產能升高時會排放出含有醋酸,硝酸及氮氧化物等高濃度酸性氣體,而NOx對人體的健康有一定的影響,該物質屬於空氣污染防制法中管制排放的物種,應妥善處理避免造成企業形象不佳及影響周遭居民的健康。光電廠之粗糙化蝕刻製程、化學氣相沈積及反射層鍍膜製程,為產生NO x的主要來源。 太陽能廠普遍使用填充洗滌塔處理廢氣,入口濃度測得NOx:329~382ppm。因其洗滌塔處理效果不佳,經處理後煙囪排放廢氣中仍含有NOx (黃棕色氣體),測得50~70ppm的NO x。去除效率為72%。 利用設備分流方式,經由排氣風管將NOx廢氣抽至頂樓以填充洗滌塔處理,尤其在第三次分流後,新增再生型除煙除酸過濾觸煤吸附塔及加藥處理後去除效率可達89%,煙囪廢氣NOx濃度明顯下降至15~37ppm,只出現微淡黃煙,可達到廢氣除酸,去除黃煙淨化空氣之目的。以月產能40~50 MW (百萬瓦)而言,原設計除酸除黃煙加藥方式,每日運轉成本約台幣6525元。分流及新增Acid2 (Scrubber)再生型除煙除酸過濾觸煤吸附塔後,每日運轉成本降至台幣3372元。
Optoelectronics industry has developed rapidly in recent years in Taiwan. Higher capacity emitted higher concentrations of acetic acid, nitric acid and NOx gases to Atmosphere. The yellow-brown smoke from stack ruined corporate image and influence the health of surrounding residents. Texturing, PECVD, and the reflective layer coating processes are the main sources of NOx generated. Photovoltaics factory commonly used the scrubber to treat exhaust gas. Usually, the inlet NOx concentrations was 329 ~ 382ppm. Due to the ineffectiveness, the yellow-brown gas could be seen from the stack, the emission concentration of NO2 measured still had high value of 50 ~ 70ppm . The removal efficiency had only 72%. The redistribution of duct arrangement, addition of another regenerative acid scrubber, and replacement of different chemical reagent had been used to solve this perplexed problem. After three tries, the removal efficiency of 89% could be attained and the exhaust NOx concentration was decreased to 15 ~ 37 ppm, only light yellow smoke could be seen.For monthly production capacity of 40 ~ 50MW, the new daily operating cost of acid gases removal system were dropped to 3372 NTD, compared with the original 6525 NTD.