PrintThe focus of this course is on how to use an existing reactive transport code, not on how to numerically solve reactive transport equations, which deserves a separate course by itself. Readers who are interested in numerical methods of RTM are referred to book chapters and literature for details of discretization of the equations and numerical solution.
The rest of the course is structured as follows. Unit 1 includes lessons that teach principles and set up of geochemical reactions in well-mixed systems (zero-dimension in space, well-mixed systems). In this unit, the equations solved are ordinary differential equations (ODEs) with time as the independent variable however without space dimensions. Lesson 1 focuses on the concepts of primary and secondary species, reaction thermodynamics, and aqueous complexation reactions. Lesson 2 teaches mineral dissolution and precipitation reactions and Transition State Theory (TST) rate law. Lesson 3 is on surface complexation reactions. Lesson 4 teaches ion exchange reactions. Lesson 5 teaches microbe-mediated reactions.
Unit 2 teaches principles and set up of solute transport processes. This is where we introduce the space dimension. Here we solve Advection-Dispersion equation (ADE) without reactions in a one-dimensional system (lesson 6). Lesson 7 teaches principles and set up of heterogeneous, two dimensional domains.
Unit 3 combines biogeochemical reactions in Unit 1 and solute transport processes in Unit 2. Lesson 9 is an example of 1D transport with multiple mineral dissolution and precipitation reactions. If you run the simulation sufficiently long and allow the properties change over time, it becomes a chemical weathering simulation. Lesson 9' intends to have you combine solute transport with microbe-mediated reactions based on lessions 5 and 6. Lesson 10 introduces a 2D system with both physical and geochemical heterogeneities.