Lightweight Micro-Proppant Fracture Placement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional hydraulic fracturing methods face challenges in efficiently creating and maintaining fractures in subterranean formations due to high friction pressures caused by turbulent flow and premature settling of heavy proppants, which limits the effectiveness of proppant placement and hydrocarbon production.
Innovation Solution
The use of lightweight micro-proppants with specific gravities between 0.9 and 1.4 and average diameters of 0.1 to 80 microns, which can more readily traverse fracture networks and be placed in microfractures further from the wellbore, combined with macro-proppants in primary fractures, to form a proppant pack that enhances fracture conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If heavy proppants are used to effectively prop open fractures, then fracture support is improved, but friction pressure increases and proppant placement efficiency deteriorates
Solution Approach 1:
The patent changes the density parameter of proppants by introducing lightweight proppants with density less than 2.0 g/cm³ (preferably 1.0-1.8 g/cm³) to replace traditional heavy proppants. This parameter change reduces the specific gravity of proppant particles, allowing them to remain suspended longer in the fracturing fluid and travel deeper into the formation without premature settling, thereby improving placement efficiency while maintaining fracture support capability
Solution Approach 2:
The patent employs composite proppant systems combining lightweight proppants (such as polymer beads, glass microspheres, or coated particles) with the fracturing fluid matrix. These composite structures provide both the necessary buoyancy for deep placement and the mechanical strength required to prop open fractures, resolving the contradiction between fracture support and placement efficiency
2Strength
If treatment fluid is pumped at high pressure to create fractures, then fracture creation is improved, but friction pressure between fluid and formation increases
Solution Approach 1:
The patent changes the rheological parameters of the treatment fluid by incorporating friction reducing agents and optimizing fluid viscosity. This allows the fluid to be pumped at lower pressures while still achieving the necessary fracture creation, thereby reducing friction pressure between the treatment fluid and the subterranean formation
Solution Approach 2:
The patent introduces friction reducing agents as intermediary substances that modify the interaction between the treatment fluid and the formation. These agents reduce the coefficient of friction at the fluid-formation interface, allowing high-pressure fracture creation with reduced overall friction pressure losses
3Strength
If proppant concentration is increased to improve fracture propping, then fracture support is improved, but friction pressure and proppant settling increase
Solution Approach 1:
The patent changes the density parameter of proppants to lightweight materials with density less than 2.0 g/cm³, which increases the suspension stability of proppant particles in the treatment fluid. This allows higher proppant concentrations to be maintained without excessive settling, improving fracture propping while controlling friction pressure and settlement issues
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
This approach reduces friction pressures, allows for deeper and more effective placement of proppants, increasing hydrocarbon production by maintaining fractures open and improving the conductivity of the fracture network, thereby enhancing well productivity.
Implementation Method 1
lightweight micro-proppant, which may be used to prop open not only near-wellbore microfractures but also far-field microfractures. Without being limited by theory, it is believed that lightweight micro-proppant may more readily traverse a fracture network and be placed in microfractures further from the wellbore as compared to a heavy micro-proppant that are prone to premature settling
Implementation Method 2
The particulate solids, known as 'proppant particulates' or simply 'proppant' serve to prevent the fractures from fully closing once the hydraulic pressure is removed. By keeping the fractures from fully closing, the proppant particulates form a proppant pack having interstitial spaces that act as conductive paths through which fluids produced from the formation may flow
Implementation Method 3
To achieve pressures above the fracture gradient, the treatment fluid is generally introduced at high pressures and/or high flow rates, which can cause turbulent flow of the treatment fluid. Such turbulent flow can result in friction pressure between the treatment fluid and subterranean formation equipment (e.g., wellbore piping, wellbore casing, and the like), as well as between the treatment fluid and the formation itself
Data Source
AI summary
Lightweight micro-proppant suitable to prop open not only near-wellbore microfractures but also far-field microfractures. Some methods of fracturing and propping may comprise first introducing a pad fluid comprising a lightweight micro-proppant into a wellbore penetrating a subterranean formation at a rate and pressure sufficient to create or extend a fracture network in the subterranean formation, wherein the fracture network comprises microfractures. The lightweight micro-proppant comprises a thermoset nanocomposite having a specific gravity of about 0.9 to about 1.4 and having an average diameter of about 0.1 microns to about 50 microns. Then introducing a proppant slurry comprising a macro-proppant into the wellbore penetrating the subterranean formation after introducing the pad fluid forming a proppant pack in the fracture network wherein at least some of the lightweight micro-proppant is located in the microfractures.