Bioremediation of kerosene II: a case study in contaminated clay (Laboratory and field: scale microcosms)

Abstract

Kerosene contaminated clay results in large amounts from the treatment of Jet kerosene produced from Merox process, in the Middle East Operation and Maintenance for Oil Refineries (MIDOR), Alexandria and represent a great environmental pollution problem. The treatment of the clay was performed with natural attenuation, biostimulation and bioaugmentation in lab and field-scale microcosms. More than 90% of the kerosene was biodegraded in bioaugmentation and biostimulation processes, while only 50% was obtained by natural attenuation after seven weeks. Urea 46% and superphosphate 15.5% were used as nitrogen and phosphorus sources due to their low cost and local availability. The immobilized cells enhanced the biodegradation processes and reduced the time. Dehydrogenase activity was affected by the time and type of the treatment. The degradation percent was found to be 85–90% at temperature range 21–24°C, while only 57–68% was obtained at temperature 15–17°C. The lab-scale microcosm was scaled up to field microcosm with a great success.