CO_2 Sequestration Potential of Geologic Formations in India

摘要

Carbon dioxide (CO_2) capture and storage (CCS) is identified as a promising technology for CO_2 mitigation within the public policy in India. This paper estimates the CO_2 storage potential for India. The suitable geologic formations are basalt formations including interbedded sedimentary beds, deep saline aquifers, unmineable coal seams, and depleted oil and gas reservoirs. Unlike sedimentary formations that have received much attention, basalt formations are being considered as a potential sink for CO_2 only recently. Basalts have inimitable properties favorable for chemical trapping of the injected CO_2 efficiently and everlastingly isolating it from the environment. Estimation of CO_2 storage potential in India is prepared by using empirical formulae and considering the geographical extension, thickness, depth, storage capacity, rate of conversion, and porosity of formation. Total CO_2 storage potential is estimated to be 572 Gt of which Basalt formations in the Deccan and Rajmahal traps contribute 200 Gt, total onshore and offshore deep saline aquifers (360 Gt), unmineable coal seams (5 Gt), and depleted oil and gas reservoirs (7 Gt). This is an initial estimation for CO_2 storage potential and would be useful for building upon this research for more specific estimation.