Non-aqueous Liquid Anti-shrinkage Cement Additive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional cement compositions in well cementing face challenges with shrinkage during hydration, leading to stress and potential failure of the cement sheath, which can result in micro-annuli, fluid migration, and compromised zonal isolation, necessitating costly repairs or well abandonment.
Innovation Solution
A non-aqueous liquid anti-shrinkage cement additive comprising a hydrocarbon liquid, dispersant, viscosifying additive, emulsifying agent, and calcined magnesium oxide is used to reduce or eliminate shrinkage, providing a swelling force that counteracts inward forces within the cement composition, thereby maintaining volume and enhancing mechanical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional cement composition is used, then the cement sheath provides structural support and fluid isolation, but the cement composition shrinks during hydration causing stress and potential failure
Solution Approach 1:
The patent changes the physical and chemical parameters of the cement composition by incorporating specific additives (calcium aluminate cement, expanding clay, lime) that modify the hydration process. These parameter changes enable the cement to expand slightly during setting rather than shrink, counteracting the harmful shrinkage-induced stresses while maintaining structural integrity and reliability of the cement sheath.
2Strength
If anti-shrink additive is added to enhance mechanical properties, then premature failure is prevented, but the additive composition complexity increases
Solution Approach 1:
The patent employs composite materials by combining multiple additives (calcium aluminate cement, expanding clay, lime) that work synergistically to enhance mechanical properties. This composite approach provides comprehensive performance improvement including strength, flexibility, and shrinkage compensation, while the additives are integrated into a unified cement composition formulation that manages complexity through proven compatibility and coordinated function.
3Productivity
If cement composition shrinks during hydration, then hydration process completes, but micro-annuli form and zonal isolation is compromised
Solution Approach 1:
The patent applies preliminary anti-action by incorporating expanding additives (expanding clay, lime) that generate expansion forces during early hydration to counteract the subsequent shrinkage forces. This preliminary counter-measure prevents the formation of micro-annuli and maintains continuous zonal isolation throughout the hydration process and beyond, ensuring both complete hydration and reliable isolation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The non-aqueous liquid anti-shrinkage cement additive effectively reduces shrinkage and enhances the mechanical properties of the cement sheath, preventing premature failure, maintaining zonal isolation, and reducing the risk of costly repairs or well abandonment.
Implementation Method 1
providing a swelling force that counteracts inward forces within the cement composition
Implementation Method 2
effectively reduces shrinkage and enhances the mechanical properties of the cement sheath
Data Source
AI summary
The present disclosure relates to a method of cementing comprising: providing a cement composition comprising: water, a cement, and a non-aqueous liquid anti-shrinkage cement additive comprising calcined magnesium oxide and a non-aqueous liquid; introducing the cement composition into a subterranean formation; and allowing the cement composition to set in the subterranean formation. Non-aqueous liquid anti-shrinkage cement additives, cement compositions, and systems are also provided.