利用产氢强化微生物降解原油产甲烷实验

Experiment of microbial degraded crude oil producing methane enhanced by hydrogen production

在微生物降解原油产甲烷过程中,如何有效地提高微生物产甲烷能力是目前研究的技术难点之一。为了能够在短时间内利用微生物产生更多的甲烷气,提高产甲烷效率,利用污水处理厂活性污泥具有产氢和产甲烷的特性,筛选出具有稳定产氢能力的产氢菌,其菌液每100 mL产氢量可达到0.8 mmol左右;再利用产氢菌培养后产H2和CO_(2)以及发酵液中挥发性脂肪酸积累的特性,为产甲烷菌提供相对充足的代谢营养底物来提高产甲烷效率;通过产氢、产甲烷两阶段培养的方式,在20 d内产甲烷能力即可得到显著提升,所产气体中甲烷体积分数可达79%以上,与传统非结合方式产甲烷气体系相比,产甲烷速率提高了10倍,达到0.0875 mmol/d,证明了应用该方法提高产甲烷效率的有效性。研究成果为进一步提高微生物降解原油产甲烷的转化效率提供了技术方向,同时也为CO_(2)注入产甲烷等技术的研究提供了借鉴。

In the process of methane production by microbial degraded crude oil,how to effectively improve methane production capacity of microbial is one of the technical challenges in current research.In order to use microbial to produce more methane gas in a short time and improve methane production efficiency,hydrogen producing bacteria with stable hydrogen production capacity are selected based on the characteristics of hydrogen production and methane production of active sludge in produced water treatment plant,with hydrogen production reaching about 0.8 mmol per 100 mL bacteria fluid.Then with the help of characteristics of H2 and CO_(2) production by hydrogen producing bacteria after cultivation and volatile fatty acid accumulation in fermentation liquid,methane producing bacteria are provided with relatively sufficient metabolic nutrient substrates to improve methane production efficiency.By means of 2 stages cultivation of hydrogen production and methane production,methane production capacity is significantly improved in a short time during 20 d,with methane volume fraction of 79%in produced gas.Compared to traditional non-combination mode methane gas production system,methane production rate is increased by 10 times to 0.0875 mmol/d,proving the effectiveness of this method to improve methane production efficiency.The research results provide technical direction for further improving conversion efficiency of microbial degraded crude oil to produce methane,and provide reference for research on technologies such as CO_(2) injection to produce methane.