Weon Shik Han’s Research
My research focuses on environmental, climate change, and energy related research such as geologic CO2 sequestration, groundwater hydrology, and geothermal energy development with an emphasis in multi-phase phenomena, reactive transport modeling, and heat transport. The methods I prefer range widely, from analytical and numerical approaches to field applications. Thus, my research includes interdisciplinary approaches, integrating elements of groundwater hydrology, hydrogeochemistry, geology, thermodynamics, and petroleum engineering.
Students interested in graduate studies on coupled processes in groundwater flow emphasis on computation simulations are encouraged to contact Weon Shik Han. Undergraduates interested in research experience and work opportunities should also contact.
Current projects are:
Role of various heterogeneity structure (e.g., low-k lens, cross-bedding, and channels) on multiphase transport of supercritical CO2, and CO2 trapping mechanisms, and buoyancy-driven migration.
To help clarify what processes and properties will maximize CO2 trapping and minimize CO2-buoyant flow, we are collecting field data and performing a systematic analysis of stochastically developed permeability (k) fields.
Han, Weon Shik et al., 2010, Evaluation of CO2 trapping mechanisms at the SACROC northern platform, Permian basin, Texas, site of 35 years of CO2 injection. American Journal of Science, 310, 282-324.
Han, Weon Shik et al., 2010, Effect of permeability on CO2 trapping mechanisms and buoyancy-driven CO2 migration in saline formations. Water Resources Research doi:10.1029/2009wr007850.
Han, Weon Shik et al., 2011, Sensitivity study of simulation parameters controlling CO2 trapping in saline formation. Transport in Porous Media (In Press)
Non-isothermal effect, heat transport in CO2 sequestration and their application to secure CO2 storage and monitoring
We are establishing the theoretical framework of temperature changes caused by CO2 related chemical reactions (e.g., Joule-Thomson cooling, endothermic water vaporization, and exothermic CO2 dissolution) in the observation wells and testing with numerical simulation tools. Simulation results suggest that these processes - solid NaCl precipitation, buoyancy effects, Joule-Thomson cooling, water vaporization, and exothermic CO2 reactions - are strongly coupled and dynamic (transient). Overall, a fundamental understanding of potential thermal processes investigated through this research will be beneficial in the collection and analysis of temperature signals collectively measured from monitoring wells.
Han, Weon Shik et al., 2010, Evaluation of potential non-isothermal effect and heat transport during CO2 sequestration. Journal of Geophysical Research-Solid Earth, doi:10.1029/2009jb006745.
Dynamics of cold-water geysers
At CO2 injection sites, CO2 leakage from the storage formation could be catastrophic. CO2 is a highly compressible fluid, typically injected at high pressure and temperature conditions. If this compressed CO2 reaches highly permeable conduits such as faults and fractures, CO2 could leak unabated to other formations (e.g. fresh water aquifers) and/or to the surface. Assuming a fast-flow path to the surface, CO2 escaping from the storage formation instantaneously reaches the surface while experiencing adiabatic expansion, which results in Joule-Thomson cooling. The addressed eruptive mechanisms are analogues to natural CO2 eruption mechanisms, which are found in CO2-driven cold-water geysers around the world. A notable example of a CO2-driven cold-water geyser is the Crystal Geyser in central Utah. We are currently investigating the dynamics of CO2 eruption mechanisms in cold-water geysers, and our approaches include field data collection, analyses and computer simulations.
Other topics of interest include equations of states, salt-water intrusion, estimation of regional scale permeability, water-rock interactions, and noble gas (helium) transport in subsurface.