Abstract
During recent years reduction of carbon dioxide emission driving development of different technologies for CO2 capturing and utilization. Carbon dioxide injection in underground reservoirs is on of effective methods for storage or utilization as enhanced oil recovery agent. Selection of the potential reservoir for CO2 injection is critically important for long term gas storage. In this paper demonstrated software solutions and workflows for modelling of geomechanical modelling of CO2 injection.
Injection of CO2 into the reservoir entails a change in reservoir pressure and a change in reservoir temperature. In turn, the stress-strain state of the massif changes, which can lead to the destruction of the reservoir rock and host rocks, reactivation of faults, and, as a consequence, the loss of the integrity of the seal and uncontrolled interstratal crossflows. This paper will describe an example of choosing a reservoir for CO2 injection based on the study of the stress-strain state of the rock mass and its changes due to gas injection.
Currently, there are various approaches to CO2 recovery into the reservoir, including injection into depleted gas reservoirs, aquifers and oil reservoirs for the purpose of enhanced oil recovery. For injection planning, it is extremely important to understand both the initial injection conditions and their changes over time.
In the work on the published materials, the world experience of CO2 injection into the reservoir with the aim of its utilization was studied.
Using the tools of combined geomechanical modeling of the reservoir, the modeling of the change in the stress-strain state of the massif during the injection process was carried out and the conditions under which the destruction of the reservoir cap and the reactivation of faults occur. The influence of uncertainty in elastic-strength parameters on the critical state of the rock mass and the potential of the permissible injection volume is shown. Comparison of injection potential into reservoirs with terrigenous and carbonate seals has been performed.
PROBLEM OF NUMERICAL MODELING OF STRESS-STRAIN STATE AND STABILITY OF FRACTURED ROCK MASS
