Efficiency of biostimulation and bioaugmentation processes in the treatment of soils contaminated with hydrocarbons

Abstract

In this work, was studied and compared two bioremediation processes of sludge generated in service stations and fuel sales stations in the city of Tunja-Boyacá, Colombia, which are contaminated with total petroleum hydrocarbons (TPH). The mud samples were collected in the grease traps of the stations to be treated using biostimulation and bioaugmentation techniques; comparing the results with a control sample to evaluate the efficiency of the processes. The tests were carried out during 12 weeks, observing the variations of temperature, pH, moisture, and final concentration of TPH. The results obtained indicate that the bioaugmentation technique presents a better performance in the removal of TPH, reaching a 75.4% decrease in TPH. The biostimulation technique presented the lowest results, reaching only 54.9% for the same period of time evaluated. From the projection it is established that the bioaugmentation technique would have the ability to reduce treatment times by up to 28.6% (6 weeks), which has long-term repercussions on the costs and implementation of biological treatment. These results open the possibility of implementing this type of treatment on a real scale to manage this type of by-products generated in the field of fuel sales since they are highly toxic to the environment and human health.