Simulation of Biodegradation and Sorption Processes in Ground Water

Abstract

ABSTRACTA one‐dimensional, finite‐difference model for simulating biodegradation and sorption processes in saturated porous media is developed. The model formulation is general and capable of accommodating a variety of boundary conditions and process theories. Advective and dispersive transport of a substrate and an electron acceptor are considered. Aerobic biodegradation is modeled using a modified Monod function; anaerobic biodegradation is modeled using Michaelis‐Menten kinetics. In addition, first‐order degradation is allowed for both substances. Sorption can be incorporated using linear, Freundlich, or Langmuir equilibrium isotherms for either substance. Dirichlet, Neumann, or Cauchy boundary conditions are allowed, where they are constant in time, or include first‐order degradation. The resulting nonlinear problem is solved using a Newton‐Raphson iterative technique. Model verification is achieved through a series of simulations, two of which arc included. In addition, three applications demonstrate the utility of the model.