Techno-economic assessment (TEA) and life-cycle assessment (LCA) of CO2-EOR in Kazakhstan

CO2-EOR is the tertiary form of oil recovery that increases oil production and sequesters CO2 under the ground. CO2-EOR can provide the knowledge and experience required to speed up carbon capture and storage (CCS) deployment. We have developed a techno-economic model of CO2-EOR, which has integrated a life-cycle assessment (LCA) tool to assess the sustainability aspect of CO2-EOR. The technical model estimates the balance of three fluids (oil, CO2, and water) in the CO2-EOR system based on a large dataset of CO2-EOR reservoirs performance data. Fluid balances were used in the calculations of LCA and the economic model of CO2-EOR. The economic model was developed based on the data from Kazakhstans oil and gas markets. The total GHG emission factor of CO2-EOR in Kazakhstan was 697 kg CO2 eq./bbl oil, further offset by the displacement of electricity when CO2 came from the coal-fired power plant. The net GHG emission factor of CO2-EOR in Kazakhstan was 359 kg CO2/bbl oil which is lower than conventional oil production methods (~500 kg CO2/bbl oil). When CO2­ came from the coal-fired power plant, the oil production cost (OPC) of the CO2-EOR was 67-72 USD/bbl oil which is more expensive than the current OPC of (10-66 USD bbl/oil) Kazakhstan. The OPC decreased to 56-60 USD/bbl when CO2 was from low-cost CO2 capture sources such as ammonia production, steel, and iron production. Favorable policies such as increasing CO2 cost in carbon trading can bring down OPC to 43-46 USD/bbl. Cost analysis of CO2-EOR showed that now it can compete with conventional means of oil production if CO2 is sourced from low-cost CO2 capture sources or if CO2 cost in carbon trading increases.