International Research Journal of Public and Environmental Health
Vol.6 (7),pp. 135-143, November 2019
Available online at https://www.journalissues.org/IRJPEH/
Author(s) retain the copyright of this article. Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License.
Original Research Article
Migration of petroleum hydrocarbons from ground surface to groundwater accounting for a liquid Arrhenius model
Elie SIMO1*, Jimy Sinclair KENHAGO WATIA2, Steve Christopher SONGONG TSAKEU3, Josue Ivan Charles ZAMBE3, Georgette Raïssa SIMO KAMDEM3 and Franklin William TABEKOUENG3
1Physics Department, Laboratory of Technologies of Energy and Environment -Faculty of Science, University of Yaounde I, P.O. Box 812 Yaounde – Cameroon.
2Physics Department, Faculty of Science, University of Dschang, P.O. Box 96 Dschang – Cameroon.
3Physics Department, Laboratoire des Sciences du Matériau -Faculty of Science, University of Yaounde I, P.O. Box 812 Yaounde – Cameroon.
* Corresponding Author Email: esimotc(at)yahoo.com
The process of petroleum hydrocarbons migration from the ground surface to groundwater was analyzed. We assumed that the diffusivity is linearly dependent on the concentration in soils. A liquid Arrhenius model of diffusion was adopted in groundwater. The nonlinear diffusion equation of the system was solved numerically. In this sense, we introduced the method of fourth-and-fifth-order Runge-Kutta using the DOPRI5 code as integrator. We sought for conditions under which petroleum products spilled on the ground surface can reach water tables. Three hydrocarbon products were involved in the calculations: benzene, toluene and xylene. We assessed the concentration of pollutants, when they reach the groundwater, for different depths to water. We found that the reachability and the degree of contamination of the water table depend on four main parameters: 1) the value of the initial concentration on the soil surface, 2) the depth to water, 3) the time period and 4) the type of hydrocarbon. For instance, calculations have shown that 5.0kg/m3 Xylene takes about one hour to reach a water table located at 120 m. This study presents separate curves describing the contaminant distribution in soil and groundwater. When Benzene reaches the water table, it takes about 250 days to cover 10 cm depth in the water. Here, the descending motion is significantly slowed.
Key words: Petroleum-contaminated soils and water, drinkable water, porous media, diffusion, liquid Arrhenius model, biodegradation, DOPRI5 Runge-Kutta integrator