MEOR菌的产气性能研究

Biogas Producing Capacity of Some Bacterial Species for Enhancing Oil Recovery

实验所用采油菌包括混合菌种和单一菌种共 8种 ,均为兼性菌 ,分别由海水、油层水、油田和炼厂污水、原油和土壤中筛选得到 ,最佳生长温度范围不同 ,低限 <2 5～ 35℃ ,高限 38～ 5 0℃。在一种培养基中分别加入不同的 5种单一碳源和实验菌中 ,在 30℃、空气帽下静态培养 2 4小时。 8种菌均能利用蜜糖和青海ZQ2 2井原油产气 ,均不能利用固态 (>C3 0 )石蜡产气 ,6种菌能利用液态石蜡产气 ,3种菌能利用大港Dg 1井原油产气。原油烃分布表明 ,QZ2 2井原油低碳数烃含量高于而高碳数烃含量低于Dg 1原油 ,两种原油都不含 <C10 烃。由QZ2 2井原油和土壤中培养出的假单胞杆菌B ,最佳生长温度 2 5～ 38℃ ,能利用除固态石蜡以外的所有实验碳源产气 ,产气量较大。在同一培养基中以体积比 2∶5的糖蜜 +QZ2 2原油为混合碳源 ,在上述培养条件下菌种B生长迅速 ,产气量为培养基体积的 47.8% ,生长时消耗O2 ,产气主要为CO2 及少量C3 ～C5烃 。

bacterial species, mixed or single, for MEOR tested in this work are all facultative aerobes and are obtained from sea waters, reservoir formation waters, oilfield and refinery waste waters, crude oils, and soil, respectively. Their optimal growth temperature is ranged from 25～35℃ to 38～50℃. These bacteria are cultivated in a culture medium with different single carbon source under air gap at 30℃ in 24 hrs. The 8 bacterial species produce biogas by utilizing molasses and crude oil QZ22 from Qinghai and not at the presence of >C 30 solid wax; 6 of them produce biogas by utilizing liquid wax and 3 of them - by utilizing crude oil Dg-1 from Dagang. The hydrocarbon distribution of the two crudes shows that crude QZ22 contains more lower carbon number hydrocarbons and less higher carbon number ones than crude Dg-1 does and both crudes contain no <C 10 hydrocarbons. Bacterial species B (Pseudomonas sp.) are obtained from crude QZ22 and soil with optimal growth temperature 25-38℃ and produce biogas in large amount by utilizing all the test single carbon sources but solid wax. In the same medium under similar conditions, bacterial species B grow fast by utilizing molasses and crude QZ22 in volume ratio 2∶5 (as mixed carbon source) and, consuming oxygen, produce biogas by a rate of 47.8% on the basis of the volume of medium used in 30 hrs. The biogas produced consists mainly of carbon dioxide and of C 2-C 5 hydrocarbons in a small amount and no methane is formed.