Associative Polymer Fracturing Fluid for Low Residue and Shear Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fracturing fluid systems for tight and shale hydrocarbon reservoirs face challenges such as high residue damage, poor shear resistance, and complex composition, leading to increased operational costs and environmental concerns due to the use of multiple additives and high water usage.
Innovation Solution
A multi-functional hybrid fracturing fluid system utilizing an associative polymer as both a friction-reducing agent and thickener, specifically modified natural or synthetic associative polymers, is developed, which simplifies the composition and preparation process while enhancing sand carrying capacity and shear resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If guar gum fracturing fluid system is used to achieve sufficient viscosity for sand carrying, then sand carrying capacity is improved, but gel breaking residue damages the formation
Solution Approach 1:
The patent changes the chemical composition parameters by replacing guar gum with hydrolyzed polyacrylamide as the thickening agent. This parameter change maintains the required viscosity for sand carrying while eliminating the gel breaking residue that causes formation damage, as HPA does not require cross-linking agents and breaks down more completely
Solution Approach 2:
The patent uses a composite fluid system combining hydrolyzed polyacrylamide with friction reducing agents and other additives to create a fracturing fluid that achieves both high viscosity for sand carrying and low residue for minimal formation damage
2Strength
If gel fracturing fluid system is formed by cross-linking technology to achieve sufficient viscosity, then sand carrying capacity is improved, but shear resistance is poor for large-scale fracturing
Solution Approach 1:
The patent changes the rheological parameters by using hydrolyzed polyacrylamide which provides shear-thinning behavior without cross-linking. This allows the fluid to maintain high viscosity at low shear rates for sand carrying while exhibiting good shear resistance at high shear rates during pumping operations
3Quantity of substance
If high viscosity gel fracturing fluid system is used to carry proppant, then sand carrying capacity is improved, but construction friction increases and equipment load increases
Solution Approach 1:
The patent optimizes the viscosity parameter by using hydrolyzed polyacrylamide which provides adequate viscosity for proppant suspension without the excessive viscosity of cross-linked gels. This reduces construction friction and equipment load while maintaining sufficient proppant carrying capacity
Solution Approach 2:
The patent utilizes the dynamic rheological properties of hydrolyzed polyacrylamide solutions which exhibit shear-thinning behavior. The fluid maintains high viscosity when stationary or moving slowly to carry proppant, but viscosity decreases during high-speed pumping to reduce friction and equipment load
4Reliability
If multiple additives are used in slick water and gel fracturing fluid to meet formation requirements, then fracturing performance is improved, but quality control difficulty and preparation complexity increase
Solution Approach 1:
The patent employs hydrolyzed polyacrylamide as a multi-functional agent that serves as both thickener and friction reducing agent. This universal application reduces the number of different additives required, simplifying quality control and preparation processes while maintaining effective fracturing performance
Solution Approach 2:
The patent merges the functions of multiple additives into a single hydrolyzed polyacrylamide-based system. By combining thickening, friction reduction, and proppant suspension functions into one primary agent, the preparation process becomes less complex and quality control more manageable
5Quantity of substance
If high concentration proppant is used in slick water fracturing to improve fracture conductivity, then fracture conductivity is improved, but proppant settling increases and carrying capacity decreases
Solution Approach 1:
The patent optimizes the fluid viscosity parameter using hydrolyzed polyacrylamide to achieve the right balance for high proppant concentration suspension. The modified viscosity characteristics prevent proppant settling while maintaining adequate carrying capacity throughout the fracturing operation
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 system reduces the amount of sand carrying fluid, lowers operation friction, and minimizes formation damage, facilitating easier recycling and reuse of flowback liquids, thus improving operational efficiency and environmental sustainability.
Implementation Method 1
adding friction-reducing agent (anionic polymer or low concentration of guar gum, etc.)
Implementation Method 2
using associative polymer as both a friction-reducing agent and thickener
Implementation Method 3
this type of jel system is not resistant to shear, so it is not suitable for large-scale fracturing which requires resistant to shear for a long time
Data Source
Figure 1
Figure 2
Figure 3~4D
AI summary
The present invention provides a multi-functional hybrid fracturing fluid system, comprising slick water and high viscosity sand carrying fluid, wherein the slick water contains 0.02%∼0.15% of friction-reducing agent by mass percentage, the high viscosity sand carrying fluid contains 0.2%∼0.75% of thickener by mass percentage; the friction-reducing agent and the thickener are the same associative polymer which is a modified natural associative polymer and/or an organic synthetic associative polymer. The present invention makes use of the good friction reduction performance of low concentration of associative polymer and the good sand carrying performance of the high concentration of associative polymer, to form a multi-functional hybrid fracturing fluid system. Compared with the conventional hybrid fracturing fluid system, the multi-functional hybrid fracturing fluid system of the present invention has advantages of less additive type, simple formula and easy preparation process; at the same time, this system has better performances on friction reduction, shearing resistance and sand carrying. The flowback liquid of the system can be reused after flocculation, sedimentation, filtration and other treatments, improving the utilization rate of the water for fracturing.