An assessment of the CO_2 storage potential of the Indian subcontinent

摘要

Current annual CO_2 emissions from large industrial point sources in India,Pakistan,Bangladesh and Sri Lanka are estimated to be 721,45,17 and 3 million tonnes (Mt) CO_2 respectively. Rapid growth in annual CO_2 emissions is likely: in India,the nine planned ultramega power plants alone could add some 257 Mt CO_2 to annual emissions. The main potential CO_2 storage sites in India are located in the saline aquifers and oil and gas fields around the margins of the peninsula,especially offshore,but also onshore in the states of Gujarat and Rajasthan. There is also thought to be considerable saline aquifer CO_2 storage potential in NE India,but this is distant from the main emission sources. CO_2 sources in the centre of the peninsula appear to be poorly placed with respect to potential CO_2 storage sites. There is estimated to be about 5Gt CO_2 storage potential in India's major coalfields and oil and gas fields. It is important that India's saline aquifer storage capacity is quantified,as this will determine whether there is significant potential for the application of CCS. Pakistan will have significant CO_2 storage potential (c. 1.6 Gt CO_2) in its gas fields when they become depleted. It is also thought to have good potential for saline aquifer CO_2 storage in the Lower Indus and Potwar Basins and there is a good match between the locations of sources and potential storage sites. Bangladesh's annual CO_2 emissions from large point sources are approximately 17 Mt CO_2. It is thought to have significant CO_2 storage potential in its gas fields (c. 1.1 Gt CO_2) which will become available gradually as the individual fields are depleted. Bangladesh also probably has significant CO_2 storage potential in saline aquifers in most of the eastern half of the country,both onshore and offshore. Sri Lanka's total annual emissions of CO_2 from large point sources are estimated to be approximately 3 Mt. These will be increased by the operation of new coal-fired power plant. There may be some saline aquifer CO_2 storage capacity offshore to the north of the island,in Palk Bay and the Gulf of Mannar,but at present this requires further investigation.