220 likes | 251 Views
Gas migration studies using TOUGH2. Ellie Kuitunen UNTF 2010. Contents. Background to disposal of L/ILW TOUGH2 studies Conclusions and future work. Background. Background. TOUGH2. Numerical simulator for modelling multiphase fluid flows in porous media
E N D
Gas migration studies using TOUGH2 Ellie Kuitunen UNTF 2010
Contents • Background to disposal of L/ILW • TOUGH2 studies • Conclusions and future work
TOUGH2 • Numerical simulator for modelling multiphase fluid flows in porous media • Developed at the Lawrence Berkeley National Laboratory • Used widely in radioactive waste disposal, contaminant transport, oil sequestration studies etc
BACKFILL WASTE CANISTER CROSS-SECTION OF THE REPOSITORY TUNNEL Repository Processes • Re-saturation • Gas generation • 2-phase flow
BACKFILLED TUNNEL Sg (air) = 90% P = atmospheric HOST ROCK Sg (air) = 0% P = 3 MPa 1 m 1 m 10 m 30 m
Two-phase Flow H2 GROUNDWATER GROUNDWATER + H2 SINGLE PHASE 2-PHASE
Two-phase Flow BACKFILLED TUNNEL Sg (H2) = 50% P = hydrostatic HOST ROCK Sg (H2) = 0% P = hydrostatic HOST ROCK Sg (H2) = 0% P = hydrostatic + 10 m 45 m
Far-field Migration of Gases 900 m Gas generation 105m
Far-field Migration of Gases • Rock features • Rocks with different properties • Non-horizontal low permeability barrier • Faults
Conclusions and Future Work • Initial studies • Demonstrated use of TOUGH2 • Improved understanding of the behaviour of gases • Parametric study to investigate different features of the repository • Design • Layout • Repository materials