A coupled model for transport of multiple chemical species and kinetic precipitation/dissolution reactions with application to reactive flow in single phase hydrothermal systems

Abstract

A numerical model for computing coupled multi-component chemical reactions, multi-species chemical transport, hydrodynamic flow, and heat transfer is described. The model employs a new algorithm which solves simultaneously for multi-component reactions and solute transport in one and two dimensions and which uses kinetic formulations for mineral dissolution and precipitation reactions, making the a priori assumption of equilibrium between water and minerals unnecessary. The feature is then used to assess the validity of the local equilibrium approximation in single phase hydrothermal systems. The code is also used to examine the problem of reaction-induced porosity and permeability changes in a fractured hydrothermal system. -from Authors