CARBON DIOXIDE SEQUESTRATION IN DEEP SALINE AQUIFERS

Among the processes proposed to reduce the atmospheric concentration of carbon dioxide and, subsequently, the greenhouse effect on a global scale, one of the most promising solutions seems to be its sequestration in deep saline aquifers. The techniques of carbon dioxide injection into underground formations have been used for a long time in the field of Reservoir Engineering. Now, a valuation of the opportunity of geologic sequestration in depleted gas and oil fields or in non-minable deep coal seams is carried out, but the technique of CO2 storage in deep saline aquifers has proven particularly interesting, as these aquifers have the advantage of being widespread almost in every part in the world and of containing large quantities of CO2. The main issues related to this process are: - the modalities of injection (injection of pure CO2 or direct injection of flue gas containing carbon dioxide); - the cost of the process (including the separation, transport and storage operations); - the safety of CO2 segregation from the atmosphere in the space of thousands of years.