REMOVAL OF PETROLEUM HYDROCARBONS FROM A LOW PERMEABILITY SOIL: BIOREMEDIATION AND ELECTROREMEDIATION

 

M.A. Martínez-Prado, C.E. Soto-Álvarez

 

 

This research evaluated the combined effect of two variables: (1) the application of a low intensity current for the desorption of an organic compound present in the soil and its migration to the liquid phase (ER) and (2) the action of autochthonous microorganisms in the degradation of the organic compound (BR), in the treatment of a soil contaminated with hydrocarbons in an experimental unit with recirculation. An electrokinetic unit was built which included a pair of stainless steel electrodes (anode and cathode) to apply a low potential gradient, MSS was used as source of nutrients and mixed to ensure aerobic conditions. Two indigenous microorganisms were isolated from the contaminated soil (Asperguillus sp and Flavobacterium sp), selected because of their high diesel degradation potential and used in batch reactor bioremediation tests. It was demonstrated that electric current applied, addition of nutrients, and oxygen accelerated the microbial growth of native microorganisms in EBR experiments (6.13 ± 1.22 x 1013 CFU/mL) and were higher than in BR tests (4.57 ± 0.80 x 1013 CFU/mL); and a higher hydrocarbons removal efficiency ( EBR: 86.67 ± 2.23% vs BR: 73.18 ± 3.16%), after 190 hours of treatment.