Advancements, Challenges, and Perspectives of Flue Gas Injectionin Subsurface Formations: A Comprehensive Review

Flue gas injection into subsurface formations has emerged as a viable strategy for enhancing oil and gas recovery while also facilitating geological carbon sequestration. This comprehensive review synthesizes extensive numerical and experimental studies that assess the effectiveness of flue gas injection. It begins by outlining the primary sources of flue gas and their compositions across various industries, followed by an examination of different injection methods integrated with enhanced oil and gas recovery techniques. The review summarizes evaluation methods for gas storage capacity from existing literature, which can inform the development of advanced theoretical models and simulation tools. It analyzes the impact of flue gas injection patterns—both continuous and cyclic—on recovery factors, while also considering the effects of fracture and matrix permeability. Additionally, the study delves into the geochemical reactions between flue gas, formation brine, and rock, highlighting how these interactions can alter chemical equilibrium and influence the overall process. Recent advancements in numerical modeling techniques are discussed, featuring simulators such as Eclipse, CMG, Petrel, TOUGH2 V2, PHREEQC, and COMSOL, which provide valuable insights into the key factors and mechanisms at play. Finally, the review identifies existing knowledge gaps and offers recommendations for future research, emphasizing the need for deeper investigations into flue gas injection processes to optimize their application for enhanced oil and gas recovery and effective carbon sequestration.