CCS - Cinétique de formation d’hydrates de CO2 en milieu poreux en conditions de stockage en réservoirs déplétés

In CCS (CO2 capture and storage) CO2 storage in depleted petroleum reservoirs is envisaged. Hydrates CO2 crystals formation may lead  to important injectivity losses and even to a complete plugging of the injector well and hydrates risk is identified as crucial for the CO2 storage operation. the objectives of the PhD work aims at : 
-    Understand the CO2 hydrate formation mechanism (associated or not to salt deposit) in porous media and its impact on the injectivity (petrophysic measurements)
-    Anticipate  the hydrate formation and define the operational conditions to avoid them. 
The PhD work is experimental work. Three experimental set ups will be used with progressive increasing complexity to go towards more and more realistic conditions. Firstly in a peek high pressure cell allowing X-Ray tomography analysis, hydrates formation in static conditions in unconsolidated porous media will allow us to study and optimize CO2 hydrates kinetics in a porous media. The influence of the solid nature, their size, the water/CO2 ratio…on the kinetics will be studied. The second experimental set up will address tests at the pore size level. Microfluidic tool will be used. Hydrates formation tests will be conducted in a long capillary in which co-injection of water and CO2 will be done. Hydrate formation will be detected visually under microscope and  other detection methods could be developed. The last experimental level will be the petrophisics level. Feasibility tests on either mini core on   X-Ray coreflood platform or in a classical coreflood bench will be performed. 
The Kinetics data and the correlations determined in these three setups will be used in the reservoir models to predict the hydrates risks at the near well bore during CO2 injection in cold depleted petroleum reservoirs.