Associative Polymer Additive for Viscosity Control in Subterranean Fluids
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional subterranean treatment fluids face challenges in maintaining optimal viscosity and yield point, leading to issues such as sticking of drill strings, increased circulating pressures, and lost circulation problems, particularly when using solid particles to enhance viscosity, which can result in inadequate shear and over-treatment, and may not efficiently prevent separation of cement components.
Innovation Solution
The use of an aqueous treatment fluid with an associative polymer additive, specifically hydrophobic alkoxylated aminoplast, which increases the fluid's viscosity by more than 50% without significantly increasing the yield point, forming an associative polymer network that enhances suspension characteristics and prevents particle settling, thereby maintaining fluid stability and efficiency in subterranean operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If solid particles are used to increase fluid viscosity, then the fluid can maintain sufficient viscosity for transporting drill cuttings and preventing cement separation, but the yield point increases significantly and vigorous agitation is required to activate the particles
Solution Approach 1:
The patent changes the chemical parameter of the fluid by introducing associative polymers that form reversible physical crosslinks through hydrophobic interactions. This transforms the viscosity mechanism from particle-based to polymer-network-based, eliminating the need for vigorous agitation while achieving sufficient viscosity for cuttings transport and cement suspension.
2Stability of the object's composition
If solid particles are added to maintain viscosity, then the fluid can prevent separation of cement components, but the yield point increases and may cause sticking of drill string and increased circulating pressures
Solution Approach 1:
The patent changes the rheological parameters by replacing solid particle thickening mechanisms with associative polymer networks. These polymers provide viscosity and suspension capability through molecular entanglement and hydrophobic associations, preventing cement component separation without significantly increasing yield point, thus avoiding drill string sticking and excessive circulating pressures.
Solution Approach 2:
The patent creates a composite system combining hydrophobic polymers with aqueous treatment fluids. The associative polymers form a network structure that复合ly provides both viscosity for cuttings transport and suspension capability for cement components, while maintaining low yield point characteristics.
3Stability of the object's composition
If fluid viscosity is increased to prevent cement separation, then solid particles can maintain sufficient viscosity, but the fluid may cause sticking of drill string and increased circulating pressures
Solution Approach 1:
The patent changes the viscosity mechanism from solid particle-based to associative polymer-based. The polymers form reversible physical crosslinks that provide sufficient viscosity for cement suspension and cuttings transport while maintaining low yield point, thereby reducing circulating pressures and preventing drill string sticking.
4Ease of manufacture
If aqueous treatment fluids are used instead of oil-based fluids, then the fluids are more economical and less damaging to formation and environment, but they may not achieve the same performance characteristics
Solution Approach 1:
The patent changes the rheological parameters of aqueous fluids by incorporating associative polymers. This transformation enables aqueous fluids to achieve performance characteristics previously only attainable with oil-based fluids, including sufficient viscosity for cuttings transport, cement suspension capability, and appropriate yield point characteristics, while maintaining the cost and environmental advantages of aqueous bases.
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 solution effectively increases the viscosity of treatment fluids without raising the yield point, improving suspension of particles and preventing settling, thus enhancing the performance of drilling, cementing, and fracturing operations by maintaining fluid stability and reducing free water formation, while avoiding the need for solid additives.
Implementation Method 1
the associative polymer additive increases the PV of the treatment fluid by more than at least 50% and wherein the associative polymer additive increases the yield point by no more than about 30% of the corresponding increase in the PV
Implementation Method 2
forming an associative polymer network that enhances suspension characteristics
Implementation Method 3
enhances suspension characteristics and prevents particle settling, thereby maintaining fluid stability
Data Source
AI summary
This invention is generally related to using treatment fluids having additives that modify rheological characteristics. Some embodiments of the present invention provide methods of using treatment fluids comprising an aqueous fluid and an associative polymer additive, wherein the associative polymer additive increases the PV of the treatment fluid by more than at least 50% and wherein the associative polymer additive increases the yield point by no more than about 30% of the corresponding increase in the PV relative to a treatment fluid without the associative polymer additive in a portion of a subterranean formation.