New Materials and Technologies for Life-Lasting Cement Sheath: A Review of Recent Advances

Abstract

SummaryThe key objective of well cementing has always been to provide zonal isolation in oil, gas, and carbon dioxide (CO2) storage wells to ensure safety and prevent environmental problems. The loss of zonal isolation and wellbore failures are mostly associated with inappropriate cementing and/or cement-sheath stability problems. Depending on the operations in a well, the cement sheath can experience a range of conditions that might induce its failure. To provide a long-term zonal isolation, the cement sheath should be designed to work throughout the entire lifetime of a well. Advances in materials and technologies, such as nanomaterials, polymeric materials, controlled processes, and electrokinetic processes, are currently implemented, and can further be implemented, by the cement industry to solve problems encountered in oil/gas well cementing. This paper provides a review of advances in applications of nanomaterials in oil/gas well cementing. These include expansive nanoadditives for shrinkage mitigation, nanorubber (NR)/flexible particles for modifying mechanical properties, and charged nanoparticles for hardened-cement treatment. In addition, new technologies, such as electrokinetic methods, self-sealing processes, and controlled-release processes for adjusting cement properties, are also reviewed. We discuss how these new materials and technologies can be the solution for providing a life-lasting cement sheath, through enhanced performance of the cement sheath with reasonable cost and minimized environmental effect, both of which have high importance in the oil/gas industry.