Dicarboxylic Acid Particles in Viscoelastic Surfactant Fluids
Solution Overview
Problem
Existing fracturing fluids, particularly those gelled with polymers or viscoelastic surfactants, face issues such as premature degradation, formation damage, and excessive fluid loss during hydrocarbon recovery operations, which affect the efficiency and effectiveness of hydrocarbon production.
Innovation Solution
Incorporating solid, particulate dicarboxylic acid agents into viscoelastic surfactant-based fracturing fluids to enhance viscosity and reduce fluid loss, along with the use of mutual solvents or alcohol blends to break the gel post-treatment, allowing for improved fluid management and reduced formation damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If polymer gelling agents are used to increase viscosity, then the fluid can carry and suspend proppants, but the polymers require separate breaker compositions and leave coating on proppant that interferes with functioning
Solution Approach 1:
The patent changes the chemical nature of the gelling agent from polymer-based to viscoelastic surfactant-based, fundamentally altering the rheological parameters while eliminating the harmful polymer coating effect. The VES system provides comparable viscosity through surfactant self-assembly rather than polymer chains.
Solution Approach 2:
The patent extracts and eliminates the harmful polymer component entirely, replacing it with a surfactant-based system. The breaker composition is also simplified by removing the need for separate polymer-breaking chemicals, as VES fluids break down more cleanly.
2Strength
If crosslinked polymer fluids are used to gel the fracturing fluid, then viscosity is increased to prevent proppant settling, but the fluids cause formation damage and require complex breaking processes
Solution Approach 1:
The patent changes the fundamental chemical composition from crosslinked polymers to viscoelastic surfactants, maintaining the desired viscosity parameter while eliminating formation damage. The VES system achieves thickening through micellar aggregation rather than polymer crosslinking, avoiding the harmful effects.
Solution Approach 2:
The patent employs a disposable, easily degradable surfactant system that performs its viscosity-enhancing function during the fracturing operation and then breaks down harmlessly, unlike persistent polymer crosslinks that require complex breaking and cause formation damage.
3Object-generated harmful factors
If viscoelastic surfactant fluids are used to reduce formation damage, then less polymer cake residue is left, but significantly higher fluid leakage into the reservoir matrix occurs
Solution Approach 1:
The patent introduces a multifunctional additive system that simultaneously addresses both fluid loss control and viscosity maintenance. The combination of viscoelastic surfactant, particulate agent, and breaker creates a unified system that performs multiple functions: thickening, fluid loss prevention, and easy breakdown.
Solution Approach 2:
The patent creates a composite fluid system combining viscoelastic surfactant, solid particulate agents, and breaker compositions. This composite approach leverages the strengths of each component: VES for viscosity and low residue, particulates for fluid loss control, and breakers for post-treatment cleanup.
4Productivity
If solid particulate agents are added to increase viscosity and reduce fluid loss, then fracturing treatment efficiency improves, but the agents require mutual solvents or alcohol blends to dissolve post-treatment
Solution Approach 1:
The patent changes the solubility parameters of the particulate agents by selecting materials that are insoluble in water but soluble in mutual solvents and alcohol blends. This allows the agents to remain stable during the aqueous fracturing operation and then dissolve easily when breaker is introduced.
Solution Approach 2:
The patent uses mutual solvents and alcohol blends as intermediary substances that facilitate the dissolution of particulate agents after treatment. These intermediaries bridge the gap between the water-based fracturing fluid and the organic-soluble breaker, enabling smooth transition and dissolution.
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 use of dicarboxylic acid agents in viscoelastic surfactant fluids increases viscosity and minimizes fluid loss, thereby enhancing the efficiency of fracturing treatments, reducing formation damage, and optimizing fracture geometry and hydrocarbon production.
Implementation Method 1
a viscoelastic surfactant (VES) gelling agent present in an amount effective to increase the viscosity of the aqueous viscoelastic surfactant treating fluid
Implementation Method 2
viscoelastic surfactant (VES) gelling agent
Implementation Method 3
pumping a mutual solvent and/or a blend of alcohols solution to at least partially dissolve the dicarboxylic acid agent, and/or to decrease the viscosity of the aqueous viscoelastic surfactant treating fluid
Data Source
AI summary
Solid, particulate dicarboxylic acids may be fluid loss control agents and/or viscosifying agents for viscoelastic surfactant (VES) fluids in treatments such as well completion or stimulation in hydrocarbon recovery operations. The fluid loss control agents may include, but not be limited to, dodecanedioic acid, undecanedioic acid, decanedioic acid, azelaic acid, suberic acid, and mixtures thereof having a mesh size of from about 20 mesh to about 400 mesh (about 841 to about 38 microns). A mutual solvent or a blend of at least two alcohols subsequently added to the aqueous viscoelastic surfactant treating fluid will at least partially dissolve the solid, particulate dicarboxylic acid fluid loss control agents, and optionally also “break” or reduce the viscosity of the aqueous viscoelastic surfactant treating fluid.