Effect of biodiesel addition on microbial population in diesel storage tanks

Microbial activity is a concern in the fuel industry. The water layer developed at the bottom of storage tanks constitutes an environment with the necessary conditions for development of microorganisms that can interact and affect the infrastructure in fuel facilities. The use of biodiesel as an alternative to fossil fuels leads to the question if the microbial communities established in fuel facilities are going to stay stable or if they are going to change due to the presence of this new compound. Being aware of these changes is important because changes in microorganisms community can lead to the development of a population in which the species present are more susceptible to interact and corrode the infrastructure. In the present work we explore how the addition of biodiesel can affect microbial interactions with polyethylene by using a model microbial community obtained from a diesel storage tank. Blends of 0, 25, 50, 75 and 100% biodiesel are evaluated during 50 days. The interaction of microbial populations with polyethylene is studied through biofilm quantification and SEM imaging of plastic surfaces. The heterothrophic composition of the population is studied through culture in differential media for fungi, bacteria and anaerobes. © 2013 by NACE International.