143-Hybrid-Cells-in-Series Model Incorporating Adsorption for Solute Transport in a Stream.

Abstract

Most trace elements and many anthropogenic organic compounds are known to associate with sediments. Adsorption and de sorption take place under non-equilibrium conditions. Coupling the non-equilibrium adsorption kinetics with the primary mechanisms of advection-dispersion, the hybrid cells in series model (HCIS), an alternate to the classical Advection-Dispersion Equation (ADE) model, is extended to determine concentration of a solute downstream of a point source of pollution. The HCIS model is a conceptualized model, comprising of a plug flow zone and two thoroughly mixed unequal reservoirs, all connected in series, converts the transport process governed by the second order partial differential equation with space ordinate and time as independent variables to an equivalent process governed by a first order total differential equation with time as independent variable there by greatly simplifying the solution technique. Using the non-equilibrium Freundlich type adsorption isotherm, and unit pulse kernel coefficients, and applying convolution technique, temporal and spatial solute concentrations downstream of an injection point is simulated.