Oily wastes containing radioactive elements: estimation of hazardous properties, methods of bioremediation, and influence on soil properties

Practical experience:

 Estimation of activity concentrations of radioactive elements and total petroleum hydrocarbon content; fractionation of total petroleum hydrocarbons; estimation of geno- and eco-toxicity of the wastes; bioremediation experiments using bacteria and plants; and isolation of oil-degrading strains: identification and estimation of growth rates, oil-degrading potential, and biosurfactant activity.

 The experiments conducted and the results obtained:

 Total petroleum hydrocarbon content and activity concentrations of 226Ra, 232Th, and 40K of raw and treated oily sludges obtained in a petroleum production yard were estimated (about 15 types of wastes). It was shown that total petroleum hydrocarbon and radionuclide content differed significantly in different waste types. Asphaltenes and resins were the main petroleum fractions, and 226Ra was the predominant element in the majority of waste types. The eco-toxicity of the wastes was revealed mainly in contact biotesting with bacteria and in elutriate biotesting with Daphnia. Genotoxicity, estimated by the Umu-test, was found for a third of the waste types investigated. Twelve strains possessing oil-degrading activity were isolated from the wastes, five of which were able to produce biosurfactants. Bacillus thuringiensis EI-44 and B. pumilus KM-12 were the most efficient for decomposing the heavy fraction of oily wastes. For bioremediation of the wastes, landfarming, biostimulation, and combinations of these processes with bioaugmentation were used. Different rates of biodegradation in saturated and aromatic hydrocarbons, as well as asphaltenes and resins led to changes in the fractional composition of waste by the end of remediation. It was demonstrated that the methods of landfarming and biostimulation favored a decrease in the content of oil products and phytotoxicity of the waste. Landfarming was the most rapid process.

 Please see the following publications:

         Selivanovskaya S.Yu., Gumerova R.Kh., Galitskaya P.Y. (2013). Assessing the Efficiency of methods for the bioremediation of oil production wastes Contemporary Problems of Ecology. 5(6): 542-548.

         Gumerova R.Kh., Galitskaya P.Y., Badrutdinov O.R., Selivanovskaya S.Y. (2013).
Changes of hydrocarbon and oil fractions contents in oily waste treated by different methods of bioremediation Oil Industry. 9: 145-146.

  Please contact: Svetlana.Selivanovskaya@kpfu.ru, gpolina33@yandex.ru