Techno-economic Evaluation of CO2-EOR in Oil Reservoirs of Precaspian Basin, Kazakhstan

Kazakhstan is on the 12^th place by its oil and gas reserves in the world and the recovery rate of oil in the country remains as low as 30-35%. Kazakhstan government stated its ultimate goal to 55-60% since oil revenues constitute major portion of the national export. High recovery rates can be attained by the Enhanced Oil Recovery (EOR) techniques and by means of using CO₂ as an injection gas. Using the CO₂ from anthropogenic sources would contribute to country's climate strategy by curbing GHG emissions. The amount of additional oil to be recovered and amount of CO₂ injected and stored are vital things to construct a cost model of CO₂-EOR project. The cost model gives a clue about feasibility of the project and further investment decisions can be made. In this work, we modified and applied previously developed techno-economic models of CO₂-EOR to the oil reservoirs in Precaspian basin which holds more than 80% of country's recoverable hydrocarbons. First, we analyzed 178 oil reservoirs in the Precaspian basin for CO₂-EOR and found that 34 of them were good candidates for modeling. Second, 9.8 Mt of extra oil was estimated to be produced and 24.4 Mt of CO₂ was to be stored underground. Third, budget model consisting of capital costs, operation & maintenance costs, tax and revenue from crude oil sale showed positive Net Present Value of project under given operating strategy and economic assumptions. The sensitivity analysis showed how oil price, CO₂ price, discount rate, project lifetime and tax policy can affect the NPV of the project.

This study was supported by the Research Grant of Nazarbayev University (NLA Contract No. 284-2019//012-2019 and 091019CRP2106).