Carbon dioxide flooding in offshore Sarawak

Abstract

Carbon Dioxide (CO2) Flooding is one of the methods of Enhanced Oil Recovery (EOR). It is used to recover oil from reservoirs where initial pressure has been depleted through primary production and waterflooding. The implementation of CO2 flooding involve miscible, near miscible, or immiscible process and oil recovery is highly dependable on phase behavior between CO2, water, and reservoir oil. CO2 and reservoir oil phase behavior greatly affects fluid flow by altering mobility ratios, interfacial tensions, relative permeabilities and rates of mass transfers. Although CO2 flooding could be a immiscible, near miscible or miscible process, the fastest growing EOR process is the miscible CO2 flooding. In this process, CO2 fully mixes with residual oil to overcome capillary forces and increases oil mobility. The displacement efficiency is almost 100% as miscibility occurs when CO2 comes in contacts with the oil. This process is appropriate for reservoirs with huge reserves of CO2.