Plug and abandonment of oil and gas wells: a comprehensive review of regulations, practices, and related impact of materials selection.

Chukwuemeka, Augustine O.; Oluyemi, Gbenga; Mohammed, Auwalu I.; Njuguna, James

Abstract

This paper reviews the state of research in permanent barrier materials for plug and abandonment of oil and gas wells to identify key strengths and weaknesses of each barrier material and understand the impact of reservoir conditions and fluids on barrier failures. The influence of regulatory requirements on P and A practices and the impact of selected barrier material on possible repurposing of depleted reservoirs for hydrogen and CO2 storage are also discussed. This review reveals that previous studies in these areas have focused primarily on improving plug placement and durability without significant consideration of the potential for long term development of leakage paths in the old wellbore infrastructure (cement and casing) whose surfaces remain exposed to reservoir fluids below the permanent plug after conventional P and A. The need for a new approach to plug and abandonment materials selection and reengineering of materials placement methods to ensure permanent isolation of reservoir fluids from existing well infrastructure is herein identified especially as the stock of wells nearing their end of life grows on a global scale. A summary of studies in the accelerated degradation of Portland cement in the presence of corrosive reservoir fluid under high temperature and pressure conditions is also presented. This will significantly drive research in materials selection for alternative barrier as HPHT wells mature for permanent abandonment.

Citation

CHUKWUEMEKA, A.O., OLUYEMI, G., MOHAMMED, A.I. and NJUGUNA, J. 2023. Plug and abandonment of oil and gas wells: a comprehensive review of regulations, practices, and related impact of materials selection. Geoenergy science and engineering [online], 226, article 211718. Available from: https://doi.org/10.1016/j.geoen.2023.211718

• Journal Article Type: Article
• Acceptance Date: Mar 20, 2023
• Online Publication Date: Mar 30, 2023
• Publication Date: Jul 31, 2023
• Deposit Date: Mar 31, 2023
• Publicly Available Date: Mar 31, 2023
• Journal: Geoenergy science and engineering
• Print ISSN: 2949-8929
• Electronic ISSN: 2949-8910
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 226
• Article Number: 211718
• DOI: https://doi.org/10.1016/j.geoen.2023.211718
• Keywords: Plug and abandonment; Well barrier materials; Geopolymers; Polymer resins; Portland cement; Barrier failures; Material selection
• Public URL: https://rgu-repository.worktribe.com/output/1925270