Overview
Our work on the modeling of MICP for upscaling has primarily been focused on the following in recent years:
- calibrating a kinetic reaction model to microbially controlled ureolysis
- modeling of column and large tank experiments
- spatially mapping distributions of calcite and chemicals in time during treatment.
Current Year ’15-’16 Focus
TITLE: Stimulation of Native Bacteria for Bio-cementation at Field-Scale Treatment Depths
RESEARCHER: Deviyani Gurung (dgurung@ucdavis.edu), Mohamed Nassar
ADVISOR(S): Prof. Tim Ginn (ginntr@gmail.com), Prof. Jason DeJong
COLLABORATOR(S): Michael Gomez, Charles Graddy, Prof. Doug Nelson
THRUST: Hazard Mitigation, Cross-cutting Couple Process Simulator
USE-CASE: Design of field scale MICP treatment for liquefaction mitigation in loose sands
TRANSFORMATIVE CONTRIBUTION: The capability for coupled flow and reactive transport simulations of MICP treatment using PHT3D and COMSOL/iCP platforms in order to extend scaled tests towards field trials.
GAPS:
- Porosity and permeability reduction for PHT3D results in maintaining time step and simulation period with Matlab external loop
- Complexity in microbial dynamics and transport
- Complexity in reaction network leading to variable kinetic rates for both aqueous and mineral constituents
BARRIERS:
- Computational limitations when adding the external porosity reduction code for long simulation time.
- Computational burden and server issues due to the communication between COMSOL-Matlab-iCP.
RESEARCH APPROACH:
- Establish flow and transport properties via tracer modeling for both COMSOL/iCP and PHT3D to reflect the experimental conditions
- Use column studies to determine kinetics parameters for reaction rates
- Institute porosity and permeability reduction to PHT3D by means of external MATLAB code.
- Apply kinetics parameters from column studies into large scale model with established hydraulic properties in both COMSOL/iCP and PHT3D.
IMPORTANCE TO STAKEHOLDERS:
- Practicioners: Provides tool to assist in field scale technology deployment.
- Academia: Fundamental advances in modeling of microbially induced calcite precipitation process within porous media, particularly with respect to reaction rates at field scale.