Microbial Enhanced Oil Recovery (MEOR): mechanism, rate of biodegradation of hydrocarbon, field applications and challenges

This paper investigated the biodegradation of selected hydrocarbons (e.g., alkanes, such as decane, and others) by open mixed microbial cultures. Laboratory experiments were conducted with the aim to investigate the rate of biodegradation of dodecane using glass bioreactors over an incubation period of 31days. In the study, dodecane represented the hydrocarbon used, and the microbial activity was subjected to aerobic conditions. Mineral water was used to stimulate the microbial growth. The results obtained indicated that an increase in the rate of biodegradation can be achieved, thus resulting in an increase in the oil recovery efficiency. It can be inferred that MEOR is a "high-risk, high reward" process, depending on whether the microorganisms can produce oil recovery-enhancing chemicals by utilizing the residual oil within the reservoir as a carbon source. The high risk in this context refers to the severe constraints that the microbial system must satisfy in order to utilize an in-situ carbon source. The rewards however are that the logistical cost and difficulty in implementing the process is similar to those of implementing a waterflood.