Microbial Ecology of Petroleum Coke Based Biofilters Treating Oil Sands Process Water

Bacterial communities in PC based biofilters play a crucial role towards OSPW remediation particularly in the degradation of NAs. The comparative analysis on overall microbial community composition and active fraction of the community indicate that many aerobic hydrocarbon degraders were present within the system operating under natural conditions; however, their involvement in NAs degradation or other organics were not prominent. The active bacterial communities further explain that degradation of NAs or other organics in OSPW might be a scheme similar to beta-oxidation via anaerobic digestion (AD). Our results argue that the interpretation of underlying mechanisms based on the total community composition might not be a suitable strategy for such systems and a focus should be given to active bacterial communities especially under similar conditions.