Field Study X: Oil Waste Processing Using Combination of Physical Pretreatment and Bioremediation

Abstract

In this chapter, a field study from an oil field in Kazakhstan is described. This study ranges from lab- and pilot-scale tests to the application of a new on-site technology. Although it is related to biodegradation only marginally, this study shows a new approach to the remediation of sites with enormous oil contamination. The dense medium separation technology is based on the physical pretreatment (gravity separation in heavy suspensions), followed by bioremediation. Contaminated soil heavily polluted with petroleum substances, including macroscopic petroleum conglomerates with a fraction ≥1 mm, is initially treated by grading. The fine-grained fraction is decontaminated by biodegradation. The coarse-grained fraction is divided by the heavy-suspension separation into a heavy product and a light product. The light product consists of large and light petroleum conglomerates, which are treated by combustion or other processing. The heavy product made up of soil with other petroleum substances is treated by crushing and biodegradation together with the fine-grain fraction. Part of the process comprises recycling of process water and heavy suspension, where the process water is also used to wet the material during biodegradation.