硝基苯污染底质的微生物强化修复研究

Bioremediation of Nitrobenzene-polluted Sediments Using Pseudomonas putida

采用从污染底质中分离出的可降解硝基苯的恶臭假单胞菌,对硝基苯污染底质的微生物强化修复进行了实验室和现场实验研究.该细菌在未灭菌的河水中可以硝基苯为唯一碳源生长,低温条件下（5℃）,对于100 g的含有11.8 mg/kg硝基苯的污染底质,投加2 mL（10^7cells/mL）菌液可以在4 d完全降解底质中的硝基苯,实现对污染底质的强化修复.该过程中无须投加额外的氮、磷及其他的营养盐,说明污染底质中含有足够的细菌生长所需的营养物质.在使用河水和底质的现场实验中,当底质和河水中的硝基苯初始浓度在7-8 mg/kg、50-61 mg/L之间时,投加硝基苯降解菌可使底质和河水中硝基苯的降解时间缩短了40 h以上,河水中的硝基苯先于底质中的硝基苯被细菌所降解.

Bioremediation of nitrobenzene-polluted sediments was studied through lab-scale and in situ experiments.The polluted sediments were remediated through the addition of bacterial separated from the sediments,even at a low temperature of 5℃.Nitrobenzene at a concentration of 11.8 mg/kg was biodegraded within 4 d with the addition of 2 mL cell solution（10^7cells/mL.） No extra nutrients were needed for the bioremediation process,showing that enough nutrients existed in the sediments.For the in situ bioremediation experiment,the initial nitrobenzene concentrations at solution and sediments were 50-61mg/L and 7-8mg/L respectively.The remediation process was also enhanced through cell addition. The above mentioned nitrobenzene was biodegraded within 48 h,compared with 96 h without cells presence.Nitrobenzene in solution was removed preferentially than those in sediments.