Large volume (megatonne) carbon capture
in saline aquifers is a relatively new field of
investigation for Canadian Discovery Ltd.
(CDL). Our reservoir characterization and
hydrogeological expertise has placed us at
the front of this emergent field.
Key hydrogeological concepts used to
assess the suitability of saline aquifers for
carbon capture are:
Use of a Vector Model to
Calculate Migration and Residence Times
Flow Field Analysis: Defining the
force of brine movement in the
aquifer.
Vector Modelling: Assessing the
effect of flowing brine on the injected
CO2 mass, determining the regional
migration paths (streamlines) and
defining potential structural and
stratigraphic traps.
Residence Time Assessment:
Combining aquifer flow capacity with the magnitude of the migrating CO2
mass to determine flow velocity and migration and residence times.
Aquifer characterization is conducted to assess suitability for CO2 injection.
Typical considerations would include:
Flow Capacity and Permeability can be
Determined by Matching Pressure History
with a Composite Flow Model
Flow Capacity: State of the art
software is used to analyze flow tests,
and to determine the permeability,
thickness and shape of the aquifer.
Flow capacity is also assessed using
calibrated log and core data.
Injectivity: The ability of an aquifer
to accept injected CO2 is governed by
the flow capacity and the fracture
stress limits of the caprock and reservoir.
Injectivity is the Negative of
Deliverability Shown in this Figure
Stress Analysis: The fracture limits
for the aquifer and caprock are
determined and injection rates would
have to be tailored so that reservoir
pressure will always be less than
these.
