Estudo numérico do comportamento da pluma do sulfato de sódio, formado a partir da reação de um ácido com uma base decorrente de um vazamento em solo saturado.

Abstract

Contamination in soils and / or groundwater by fluids with high pollutant potential has been arousing scientific interest, especially in relation to environmental impacts caused to the environment. Knowledge of soil characteristics and contaminant fluids contributes to the understanding of the physical phenomena involved during runoff and dispersion of contaminants in the soil. Thus, computational fluid dynamics (CFD), coupled with knowledge of the mechanisms of transport of contaminants in the soil (diffusion and / or convection) and the degree of saturation, is an important tool that helps in quantifying the environmental impact caused, indicating the region where actions for the remediation of the medium should be concentrated. Acid leakage can be remedied by a neutralizing reaction with the aid of a base generating a salt. In view of the above, the study of the behavior of the salt formed (sodium sulfate) was carried out from the neutralization reaction of an acid (sulfuric acid) by a base (sodium hydroxide). It was assumed the one-phase and multicomponent flow model, turbulent, non-isothermal regime, two-dimensional domain and with the soil initially saturated with water (pH = 7). All simulations were performed with the ANSYS CFX® 15.0 commercial package. The simulation results allowed the visualization of the pH distribution in the saturated soil and the acid, base and salt produced profiles. In general, it was observed that increasing the velocity of water in the soil provides an advance in the dispersion of the substances (acid, base and salt produced). However, the impact caused by salt produced in the soil is low due to its low concentration.