Volume 33: CCUS Technologies for the Carbon Neutrality: Part I

Hydrogel Systems for Gas Channeling and Leakage Control in CO2 EOR and Storage in Hydrocarbon Reservoirs Xin Wen, Yang Zhao, Zhenhua Rui, Yueliang Liu, Ting Hu, Kai Du

Abstract

Injection of CO2 into hydrocarbon reservoirs is an attractive method to enhance hydrocarbon recovery and CO2 storage. However, the non-homogeneity of hydrocarbon reservoirs can lead to low sweep efficiency during CO2 flooding and leakage during CO2 storage. This inhomogeneity can be caused by highly permeable matrices and microfractures, which provide channels for CO2. Gel plugging technology is an effective technique to prevent gas escape and plays an important role in CO2 flooding and storage. Polymer gel system has good injection ability and can achieve in-depth plugging. Particle gel system has high strength, acid and temperature resistance, and can realize long-term sealing. Foam gel has good injectability and cost advantages, and less damage to the formation. Inorganic gel has good injectability and strong chemical stability. This paper reviewed the research progress and existing problems of four kinds of hydrogels and looked forward to the future development of the CO2 consistency control gel systems.

Keywords CO2-EOR, CO2 storage, Conformance control, CO2 leakage, Gel systems