Evaluation of Current Soil Bioremediation Technologies

Abstract

Bioremediation competes with other methods as an approach to an environmental cleanup of contaminated soil. Physicochemical methods available for treatment of petroleum-contaminated soils are generally costly and capital/energy-intensive, and provide destructive or separation approaches, including thermal desorption, incineration, and solvent extraction. Destructive methods often emit large quantities of greenhouse gases. Separation methods are difficult to manage because of the variable nature of the contaminants and soils, and residuals may still require appropriate environmental disposal. Comparisons between methods indicate that biological, thermal and scrubbing methods may be used to remediate soil of contaminants such as petroleum hydrocarbons, polycyclic aromatic hydrocarbons (PAH) (except some high molecular weight PAHs), phenols, nitroaromatic and halogenated compounds. Thermal or scrubbing methods have generally been used to degrade polychlorinated biphenyls (PCB), polychlorinated dibenzodi-oxins (PCDD) and polychlorinated dibenzofurans (PCDF). Where bioremediation is effective it is typically the least expensive technology option. This chapter is divided into two main parts. The first section evaluates the component elements or factors which influence technology choice. The second section examines the major technology types and their applicability, supported by performance-based case study examples.