利用生物濾床去除揮發性有機化合物之研究

Abstract

本研究從廢水處理廠取得之活性污泥篩選出有效菌株，以含有目標污染物的固態培養基來篩選微生物，挑選出可去除目標物染物 (甲苯、乙苯、二甲苯、三氯乙烷、乙酸丁酯) 的13菌株，在實驗室中對這些菌進行初步的VOCs去除能力測試，單一VOC各挑選1~2菌株，具有在進流濃度100~500 ppm、滯留時間為45秒下對目標汙染物具有90%左右的去除能力。將挑選的菌株固定化，進行實驗室小規模的單一VOC管柱去除能力。結果顯示Xylene- oxidizing bacteria X 4菌株在二甲苯進流濃度100∼900 ppm滯留時間20秒的條件下，二甲苯平均去除率為98 %，最大去除能力為3000 g/m3/h。Toluene -oxidizing bacteria T 1菌株在甲苯進流濃度為100∼600 ppm，滯留時間60秒的條件下，甲苯平均去除率為83 %，平均去除能力為51 g/m3/h，最大去除能力為110 g/m3/h。Ethylbenzene-oxidizing bacteria E 3菌株在乙苯進流濃度200∼400 ppm，滯留時間30秒之條件下，乙苯平均去除率為92 %，平均去除能力為90 g /m3/h，最大去除能力為131 g/m3/h。本研究結果顯示這些菌株可應用於生物反應器去除VOCs，極具潛力與應用價值。

The objective of this study was to examine the performance of biological treatment systems for treating single toluene, ethylbenzene, and xylene vapors from waste gases under different retention time (RT) and influent concentrations. Using the lab-scale biofilters packed with activated carbons were individually immobilized xylene-oxidizing bacteria X4, toluene-oxidizing bacteria T1 and ethylbenzene-oxidizing bacteria E3. The results indicated that the biofilter was effective in removing xylene (＞95 %) when the loading was below 400 ppm at RT 20 s. In addition, when the loading of toluene was below 500 ppm at RT 60 s the removal efficiency was 83 %. As the loading of ethylbenzene was below 500 ppm at retention time (40 s) the removal efficiency was 90 %. The maximum elimination capacity of xylene, toluene, and ethylbenzene were 3000 g/m3/h, 110 g/m3/h, and 131 g/m3/h, respectively. These results would help to improve the removal of VOCs in biological treatment systems.