標題: | 利用生物滴濾床處理苯之研究 Removal Benzene by Biofiltering |
作者: | 姜智彬 Zhi-Bing Jang 曾慶平老師 分子醫學與生物工程研究所 |
關鍵字: | 生物反應器;生物濾床;苯;甲苯;bioreactor;biofiltering;benzene;toluene |
公開日期: | 2005 |
摘要: | 本實驗利用生物滴濾床篩選到除苯效果佳之異營ZB2、ZB4、ZB6、ZB7、ZB3及ZB5,以活性濾料為擔體進行固定化,在生物滴濾床中進行苯和甲苯之去除實驗,探討系統參數如滯留時間、系統溫度、進流濃度去除效率,及進行系統比較差異性,以利實場 (Field/Full scale) 設計時操作標準之建立,並將系統排放濃度設定於「空氣污染防治法」所規定之周界環境標準 (Ambient air standard)以下,滿足及應付趨嚴之空氣品質標準,符合空氣污染物排放標準。
在苯去除實驗方面,操作期為9個月,臨界負荷(Critical loading) 為90 mg/m3/h,此時去除效率可達100%。在單獨進流測試方面,當氣體流量控制在1000 c.c/min 時,生物滴濾床反應器苯負載量在550 ppm ~ 600 ppm 時,可達 90% ~ 100% 去除效率,甲苯負載量在300 ppm ~ 350 ppm 時,可達 85% ~97% 去除效果。在混合進流測試分面,固定苯濃度1000 ppm 、甲苯濃度為50 ppm 時,氣體流量控制在1000 c.c/min下,生物滴濾床反應器可達到最大量去除苯之效率。但過高甲苯濃度 (300 ppm 以上時) 會有競爭抑制的現象產生,使去除苯效率能力下降。而在相同氣體流量下,固定苯及甲苯濃度各為300 ppm時,生物滴濾床在對苯去除效率即下降至90% 以下。此外生物反應系統中苯之主要代謝物為CO2和H2O
由結果可知,本系統可高效率同時去除苯污染物,由於系統在環境溫度16℃~32℃仍然有高去除效率,因此極適合應用於台灣本土產業之廢氣處理,操作過程系統pH值穩定,溼度控制容易,不會因操作時間長而劇增,系統操作已達半年以上,無須更換濾料,因此本生物滴濾床系統富經濟性、安全性和優越性。 ZB2、ZB4、ZB6、ZB7、ZB3 and ZB5 were immobilized with activated media to move benzene and toluene in bioreactor. In this sturdy, we immobilized microoganism to form biofilm on the bead, and then packed into the bioreactor to control benzene and toluene emission. The effect of operating parameters, including retention time, temperature, and inlet gas concentration on the removal efficiency capacity were examined . The results of this study compared with lab-scale studies in order to design the operation principle of full-scale biofilter system. The emission of upper limits set to reach current ambient air standard of benzene and toluene. In benzene removal experiments, during the continuous operation of nine month, the critical loading was 90 mg/m3/h, and the removal efficiency can be reached 100%. In single substrate inlet test that air flow of benzene was constant at 1000 c.c/min and 500ppm~600ppm , the removal efficiency can be reached 90%~100% ; under the same condition, the concentration of toluene was constant at 300ppm~350ppm and the removal efficiency can be reached 85%~97%. In mix inlet test, high concentration of toluene (>300ppm) would inhibit the benzene removal capacity (removal efficiency<90%) . When the inlet of toluene was constant at 50ppm and benzene was constant at 1000ppm, the benzene removal capacity can be reached to the maximum level . The main metabolic products of benzene oxidation were CO2 and H2O. The results of the study indicate that the biofiltering has high efficiency to remove benzene gas. In addition, the system also maintained at high removal efficiency at 16℃~32℃ temperature. Therefore, this system will be suitable to operate in Taiwan for waste gases treatment. During a long operation period, the high operation stability, low environmental impact and low pressure loss as well as the stably high removal efficiency suggest that the bioreactor is a promising technology for treatment waste gases. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#GT009229513 http://hdl.handle.net/11536/76969 |
顯示於類別: | 畢業論文 |