以厭氧生物處理法去除廢水中異丙醇及丙酮之研究

Abstract

本研究為探討微生物在厭氧條件下對異丙醇及丙酮的去除情形，分別在不同的水質參數下進行批次試驗，以了解微生物去除異丙醇及丙酮的特性。此外進行固定化微生物濾料及石英石濾料反應槽的連續流試驗，評估其去除異丙醇及丙酮的效率，並找出最佳的操作條件。 根據批次試驗結果顯示，證明異丙醇及丙酮在厭氧條件下可被微生物降解。適合微生物降解異丙醇及丙酮之pH值為7∼7.5之間，F/M約為0.12∼0.25 kg-COD/kg-MLSS/day之間。而水中碳酸氫根以及硝酸鹽的存在對微生物分解異丙醇及丙酮均有正面的影響作用。 於連續流條件下探討不同水力停留時間、有機負荷以及固定化微生物濾料與石英石濾料對處理效果的比較。實驗結果顯示，有機負荷控制在0.144 kg-COD/m3/day以下，即兩反應槽對於含有10 mg/L異丙醇或丙酮的廢水，在水力停留時間4小時以上，便能達到100％之去除率；由於半導體廢水中通常異丙醇及丙酮含量均在10 mg/L以下，因此以此操作條件應可滿足未來之放流水標準。兩種濾床之比較，以固定化微生物濾料之處理效果較佳，但因差異不大，實際運作以石英石濾料處理即可。

This study intended to investigation the effects of microorganism on Isopropanol (IPA) and acetone removals in anaerobic condition. The investigation of batch test in different water parameters to find the property of IPA and acetone removals by microorganism. Furthermore, the availability of removing IPA and acetone from immobilized and quantz filters in continuous-flow system was evaluated to find the optimum operation. The result of batch reator revealed that IPA and acetone could be degrade by microorganism. The optim pH is between 7 and 7.5. The optim F/M ratio is between 0.12 and 0.25 kg-COD/kg-MLSS/day. Bicarbonate and Nitrate present in wastewater have positive effect of IPA and acetone biodegradation. The result of continuous-flow system revealed that ,for 10 mg/L IPA and acetone wastewater ,to approach 100% IPA and acetone removal efficiency, COD loading below 0.144 kg-COD/m3/day or hydraulic retention time under 4 hour will do. Because IPA and acetone usually below 10 mg/L in semi-conductor wastewater, this optimum operation can reatch the goal of non-detected IPA and acetone in effluent water. To compare with the efficiency of two filters, less difference between two filters. In this research chosing quantz filter in practice.