Weighted linear models for simulation and prediction of biodegradation in diesel polluted soils

摘要

The purpose of this research is to find a mathematical model based on a statistical analysis to predict the evolution of the total petroleum hydrocarbons (TPH) concentrations with time in the bioremediation process of diesel contaminated soils. The analysis is useful to compare and ascertain the efficiency of different remediation treatments and the influence of both soil characteristics and initial concentration levels of hydrocarbons on the biodegradation process. An experimental design, considering two types of soil, two concentration levels of hydrocarbons and six different amendments was carried out. A total of 336 laboratory tests were conducted during a year in 48 land plots of 4 x 4 m, spreading over eight field campaigns. The results show, for the first time to the best of our knowledge, that the bioremediation process can be adjusted quantitatively to an exponential model, following a first-order kinetic equation. The model explains correctly the higher efficiency of some treatments. In the case of hydrocarbon concentrations 16,000 mg/kg, it is advisable to use slow-release fertilizer without the use of surfactant; whereas, for concentrations above 30,000 mg/kg, the addition of surfactants improves the results considerably. (C) 2019 Elsevier B.V. All rights reserved.