1-D Transport Behaviour of Emerging Contaminants in the Unidirectional Flowing Surface Waters of the Msimbazi River
Abstract
The primary objectives of this investigation of environmental pollution were to assess spatio-temporal concentrations and predictions of transport behaviour of pollutants in aqueous media. In order to attain these goals for the Msimbazi river, the analytical and numerical solutions to the 1-D advection-dispersion equation (ADE) implemented the first-type inlet condition. The MATLAB software was used to solve the analytical equation resulting from the ADE equation. The solution to the ADE model enabled effective prediction of contaminants ' spatial distribution within a distance of 200 m from a point source in the direction of flowing water. Among the first and third-types inlet conditions, the first-type had the best exponential concentration prediction with descending concentration gradients between €“100 ng/L.m and €“0.4 ng/L.m, while beyond it the concentration gradient was merely constant. These findings are the first of this type in our region to the best of our knowledge, and hence a milestone for understanding the transport behaviour of emerging contaminants, and enable estimation of probable pollution-free zones. This study gave results that can form a basis for analytical and public interventions.
Keywords: Modelling emerging contaminants; Advection-Dispersion Equation; Contaminants transport; First-type inlet condition; Concentration gradient.