HR: 1340h
AN: B33A-1009    [Abstracts]
TI: Parametric Study of CO2 Sequestration in Geologic Media Using the Massively Parallel Computer Code PFLOTRAN
AU: * Lu, C
EM: clu@lanl.gov
AF: Los Alamos National Laboratory, MS T003, Los Alamos, NM 87545 United States
AU: Lichtner, P C
EM: lichtner@lanl.gov
AF: Los Alamos National Laboratory, MS T003, Los Alamos, NM 87545 United States
AU: Tsimpanogiannis, I N
EM: ioannis@lanl.gov
AF: Los Alamos National Laboratory, MS T003, Los Alamos, NM 87545 United States
AB: Uncontrolled release of CO2 to the atmosphere has been identified as a major contributing source to the global warming problem. Significant research efforts from the international scientific community are targeted towards stabilization/reduction of CO2 concentrations in the atmosphere while attempting to satisfy our continuously increasing needs for energy. CO2 sequestration (capture, separation, and long term storage) in various media (e.g. geologic such as depleted oil reservoirs, saline aquifers, etc.; oceanic at different depths) has been considered as a possible solution to reduce green house gas emissions. In this study we utilize the PFLOTRAN simulator to investigate geologic sequestration of CO2. PFLOTRAN is a massively parallel 3-D reservoir simulator for modeling supercritical CO2 sequestration in geologic formations based on continuum scale mass and energy conservations. The mass and energy equations are sequentially coupled to reactive transport equations describing multi-component chemical reactions within the formation including aqueous speciation, and precipitation and dissolution of minerals to describe aqueous and mineral CO2 sequestration. The effect of the injected CO2 on pH, CO2 concentration within the aqueous phase, mineral stability, and other factors can be evaluated with this model. Parallelization is carried out using the PETSc parallel library package based on MPI providing a high parallel efficiency and allowing simulations with several tens of millions of degrees of freedom to be carried out-ideal for large-scale field applications involving multi-component chemistry. In this work, our main focus is a parametrical examination on the effects of reservoir and fluid properties on the sequestration process, such as permeability and capillary pressure functions (e.g. linear, van Genuchten, etc.), diffusion coefficients in a multiphase system, the sensitivity of component solubility on pressure, temperature and mole fractions etc. Several important issues are addressed, including mobility of a supercritical CO2 plume in a heterogeneous porous medium, gravity induced instabilities during CO2 plume buoyancy, and their effects on the long-term geological storage of sequestrated CO2.
DE: 0400 BIOGEOSCIENCES
DE: 0466 Modeling
DE: 0499 New fields (not classifiable under other headings)
SC: Biogeosciences [B]
MN: Fall Meeting 2005