| Time: |
June 27, 2013 |
| Lecturer: |
Dr. Holger Ott
Shell Global Solutions International BV |
| Venue: |
Pfaffenwaldring 61, Raum U1.003 (MML), Universität Stuttgart
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| Download as iCal: |
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One of the main challenges in geological CO2 sequestration is to control the migration of the CO2 plume within the reservoir in order to confine the CO2 and optimize the initial pore space utilization for CO2 storage. The key concepts are displacement and sweep efficiency; this sounds like conventional hydrocarbon reservoir engineering, but there are CO2-specific challenges: (1) CO2 is in a supercritical (SC) state under most reservoir conditions with a viscosity usually much smaller than that of the resident reservoir fluid. This might result in enhanced channeling of CO2 in heterogeneous formations and in viscous displacement instabilities (i.e. viscous fingering), in general resulting in a low sweep efficiency and thus in a low utilization of the available pore space. (2) the injection of SC-CO2 can lead to reactions with rock-forming minerals changing the properties of the initial rock-fluid system. Under certain conditions, chemical interaction can lead to the formation of preferred path ways (wormholes) with a potential impact on the migration of CO2. I will discuss experimental and numerical investigations of displacement instabilities due to channeling, viscous fingering and wormholing.
