Abstract

ACUNA, A.J. et al. Optimization of a Hydrocarbon Bioremediation System at Laboratory Scale. Ing. invest. y tecnol. [online]. 2012, vol.13, n.1, pp.105-112. ISSN 2594-0732.

The aim of this study was to optimize the parameters of moisture, temperature and ratio of nutrients to estimate the possibility of applying the technique of bioremediation in a soil contaminated with hydrocarbons. For this, an initial characterization of contaminated soil was made according to their physical and chemical characteristics and the number of heterotrophic and hydrocarbon degraders bacteria. Also the contaminant concentration by gravimetric method and by gas chromatography was studied. To optimize moisture and temperature, microcosms with moisture of 3%, 10%, 15% and 20% and temperatures of 5°C, 15°C, 28°C and 37°C were used. The monitoring of the mineralization of hydrocarbons was performed by measuring the CO₂ produced. To optimize the ratio of nutrients, different microcosms were designed and were monitored by oxygen consumption and by determination of hydrocarbons by gas chromatography. The C:N:P relationships studied were 100:20:2, 100:10:1, 100:5:0,5 and 100:1:0,1. The results indicate that the mineralization of hydrocarbons was optimal for moisture of 10% to 20% and temperatures of 25°C to 37°C with CO₂ production values of 3000-4500 mgCO₂ kg^-1. The optimal C:N:P ratio was 100:1:0,1 in which the highest oxygen consumption was and the elimination of 83% of total hydrocarbons determined by gas chromatography with 78% and 89% of n-alkanes and polyaromatic hydrocarbons elimination, respectively.

Keywords : biodegradation; hydrocarbons; soil; Patagonia.