Bioremediation, Biostimulation and Bioaugmention: A Review

Abstract

Bioremediation uses microbial metabolism in the presence of optimum environmental conditions and sufficient nutrients to breakdown contaminants notably petroleum hydrocarbons. We reviewed technologies for carrying out bioremediation and observed that biotechnological approaches that are designed to carry out remediation have received a great deal of attention in recent years. Biostimulation (meaning the addition of limiting nutrients to support microbial growth) and Bioaugmentation (meaning the addition of living cells capable of degradation) studies have enjoyed a heavy presence in literature and reviews of these technologies focusing on the technical aspects are very few if at all available. At times, nutrient application alone or augmenting with microbes is not sufficient enough for remediation leading to a simultaneous approach. Recent studies show that a combination of both approaches is equally feasible but not explicitly more beneficial. Evidently, selection of a technology hinges on site specific requirements such as availability of microorganisms capable of degradation in sufficient quantities, nutrient availability to support microbial growth and proliferation as well as environmental parameters such as temperature in combination with duration of exposure. This review focuses on these technologies and efforts are directed towards eventual manipulation of the processes of remediation all geared towards making bioremediation technically and economically viable for comprehensive treatment of petroleum hydrocarbon contaminated soils.