GASRIP’s research hypothesis is that the original mechanical properties of saline aquifer reservoirs are altered by haloclasty during CO2 storage (reservoir inflation); while posterior dissolution of the salt-bearing formation due to natural aquifer recharge post-closure may be the onset of a mechanical instability (reservoir over-compaction). This process is expected to modify also the transport properties of the reservoir. Thus, in a controlled manner, salt precipitation/dissolution associated with CO2/brine cycles could improve transport properties of tight reservoirs and so the recovery rates in unconventional reservoirs (EOR strategy).
The overall programme divides into two experimental work packages (WP1 and WP2) and a third one (WP3) to generate outcomes (datasets and software) for potential beneficiaries. The project will be developed at the National Oceanography Centre, Southampton (NOCS). NOCS facilities include equipment for He-pycnometer, XRD and ICP–OES analysis, and a number of workshops for sample preparation, including thin sections from rock samples. It also extends to the University of Southampton, where the facilities for CT-scanning are placed.
WP1. Salt precipitation/dissolution induced-damage in CO2 storage reservoirs.
- Real reservoir samples acquisition
- Brine-CO2 flow-through (BCFT) tests for determination of elastic and mechanical parameters (using the High Pressure Multi-flow Rig at the NOC)
- Mechanical compressive testing under realistic reservoir confining conditions
WP2. Induced rock weathering to enhance recovery rates of carbonate reservoirs.
- Synthetic carbonate-bearing sandstone reservoir analogues.
- Brine-CO2 flow-through (BCFT) tests using synthetic carbonate-bearing sandstone samples
- Textural and mineralogical assessment.
WP3. Data management and software