Phenomenological modelling of bioremediation systems for hydrocarbon-contaminated Chilean desert soils

Abstract

A mathematical model was developed from an experimental bioremediation system for soils contaminated with hydrocarbon mixtures and native biomass. The model was developed based on balance equations for biomass in aqueous and oleic phases, hydrocarbon in gas, aqueous and oleic phases and nutrients. Transfer from micro- and nano- soil pores to the gas phase and the kinetics expressions for biomass were considered. The model optimized parameter for the mass transfer coefficients between the aqueous and oliec phase, the aqueous and gas phases, and the gas and oleic phases; these were 2.05 x 10-3, 1.14 x 10-2 and 1.84, respectively. The value obtained for the effective diffusion coefficient Def, was 4 x 10-4 (cm2 week-1). The model allowed the determination of the nutrient concentration as a critical parameter for the design and operation of these systems.