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Although the high efficiency of coupled lithium and saturated metakaolin in alkali-silica reaction mitigation has been documented, its influence on cement hydration remains uninvestigated. In this study, saturated metakaolin with varying degrees of saturation and its combined influence with lithium on the hydration kinetics, phase evolution, and development of microstructure and molecular structures of hydration products in the blended cement composite was investigated. The experimental and thermodynamic modeling results indicate the synergistic effect between saturated metakaolin and lithium in enhancing the hydration of cement, interaction between metakaolin and cement, incorporation of Al in the silicate chains, and precipitations of Al-rich phases. In the blended cement matrix, the dissolution of metakaolin, formation of calcium silicate hydrates with incorporated aluminum (C-(A)-S-H), and precipitation of strätlingite are improved by 19.6%, 17.6%, and 20.0%, respectively, and the formation of cubic siliceous hydrogarnet was triggered.
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This content will become publicly available on October 1, 2026
Wellbore Integrity in Energy Applications: Precipitation Products after Reaction with Produced Water from the Permian Basin
Sealing of oil and gas production wells is done to protect overlying aquifers and the land surface from vertical migration of drilling fluids, produced water (PW), and natural gas. The integrity of the contact between the well casing and cement seal is especially important as both the steel and the cement are subject to reactions caused by exposure to very high salinity PW. The objective of this study was to identify corrosion and precipitation products that form at this contact and determine their effect on the microannular space between the two materials. Steel cylinders were embedded in Type G Portland cement to simulate a sealed wellbore. They were then exposed to simulated and PW sampled from the Permian Basin in the southwestern United States. Solid phases in the cement were identified by X-ray diffraction and electron microprobe analyses and included portlandite, a calcium silicate, and brownmillerite. Gas flow measurements were used to estimate the aperture of the microannulus between the steel surface and the cement. A decrease in the aperture with increasing reaction time was detected for all experiments. The findings suggest that exposure to PW has the potential to reduce the microannular space between the casing and the cement seal as a result of precipitation of calcium- and magnesium-carbonate as dominant phases, with the co-occurrence of sulfate and silicate minerals. These results have implications related to the long-term integrity of annular seals used to seal oil wells exposed to very high salinity PW.
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- Award ID(s):
- 1914490
- PAR ID:
- 10645708
- Publisher / Repository:
- Mary Ann Liebert, Inc.
- Date Published:
- Journal Name:
- Environmental Engineering Science
- Volume:
- 42
- Issue:
- 10
- ISSN:
- 1557-9018
- Page Range / eLocation ID:
- 434 to 444
- Subject(s) / Keyword(s):
- energy applications precipitation products produced water wellbore integrity
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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