Sensitivity Analysis of Operating Conditions on the Economics of CO2 Storage with EOR

Abstract

This study proposes economic evaluation of CO2 geological storage with enhanced oil recovery (CCS-EOR). The procedures were established by considering capital expenditures (CAPEX) and operating costs (OPEX) of infrastructures and revenues from oil recovery and carbon tax credit. Extensive CCS-EOR simulations were conducted to draw the best promising scenario among cases where miscibilities were controlled by producer bottomhole pressure (BHP) and liquefied petroleum gas (LPG) addition. Due to the lowest producer BHP in immiscible condition, earlier oil recovery and CO2 breakthrough, which result in low amount of CO2 sequestration, occurred. Miscible condition has found to be economically the most promising scenario with net present value (NPV) of 87 MM$ while near-miscible condition and immiscible condition showed 85 MM$ and 82 MM$, respectively. For the cases adjusting miscibilities by LPG addition, the more LPG injected, the more miscibility was developed due to minimum miscible pressure (MMP) reduction, resulting in higher oil recovery and smaller CO2 sequestration. Economic evaluation shows that the addition of 13% LPG was the most promising scenario with a NPV of 91 MM$. Sensitivity studies on economic parameters were conducted on pressure-controlled miscibility adjustment cases. When discount rate changes from 2.3% to 10%, immiscible condition became more favorable due to more oil production at earlier stage. However, miscible condition showed the highest NPV for oil price ranging from $20/bbl to $100/bbl.