Estudio de Inóculos Bacterianos como Biorremediadores de Suelos Contaminados con Petróleo

Abstract

The objective of this research is to bioremediate soils contaminated with hydrocarbons from an area of 300 m2 of the external pool of the Esmeraldas State Refinery, by using microbial inoculums in a remediation chamber at controlled temperature and humidity. The analyses were carried out in the laboratory of the Center for Technical Services and Environmental Technology Transfer (CESTTA) of the Polytechnic School of Chimborazo. Ten treatments were carried out with three replications, in which the inoculum concentration (5, 10, 15 g/mL), amount of soil (500, 1000, 1500 g) and amount of substrate (500, 1000, 1500 g) were varied. Physicochemical (photometric, gravimetric, potentiometric), microbiological and statistical methods (fisher, tukey, least squares), methylene chloride extraction techniques, HPLC determination, atomic absorption, liquid culture medium and determination of mesophilic aerobes were used. From the study, it is concluded that the contaminated soil used had two parameters (TPH -101600 mg/Kg and PAH's - 5. 81 mg/Kg) that were outside the permissible limits according to the Environmental Regulations for Hydrocarbon Operations in Ecuador, which when treated with the microbial inoculums during the six months of experimentation allowed significant bioremediation, being the T6 treatment the one that presented the highest efficiency in the reduction of TPH 60%, PAH's 80.72%, Ni 80.13%, Cd 93.89% and Pb 92.18%. Thus providing reliable information for the future regarding soil remediation technique. It is always recommended to perform bioremediation tests at laboratory level before being used in the field, to avoid any surprises.