Rod-Shaped Ceramic Proppants for High Closure Stress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional proppants, such as sand and ceramic beads, fail to maintain conductivity in high closure stress environments, leading to reduced well productivity and frequent refracturing due to settling and collapse of proppant packs.
Innovation Solution
The method involves forming rod-shaped particles from a slurry of ceramic materials with a high alumina content, which are stabilized and then reduced in length using mechanical vibration or a rotating cutting mechanism before sintering, to create proppants that can withstand high fracture closure stress and maintain conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If sand proppant is used in high closure stress environments, then cost is reduced, but proppant strength is insufficient leading to crushing and collapse
Solution Approach 1:
The patent uses composite ceramic materials containing alumina, silica, and other oxides to create proppant particles with both high strength and controlled density. This composite approach allows the proppant to withstand high closure stresses while maintaining transportability.
Solution Approach 2:
The patent controls the chemical composition parameters of the ceramic proppant, specifically adjusting alumina content and other oxide ratios, to optimize the balance between strength, density, and toughness. This parameter optimization resolves the contradiction between being strong enough to resist crushing and light enough for transport.
2Strength
If ceramic proppant with high alumina content is used, then proppant strength is improved, but specific gravity increases leading to quick settling
Solution Approach 1:
The patent optimizes the chemical composition parameters of the ceramic proppant, specifically adjusting alumina content and other oxide ratios, to optimize the balance between strength, density, and toughness. This parameter optimization resolves the contradiction between being strong enough to resist crushing and light enough for transport.
3Ease of manufacture
If conventional spherical proppant is used, then manufacturing is simple, but proppant interlocking is poor leading to reduced conductivity maintenance
Solution Approach 1:
The patent employs asymmetric rod-shaped proppant particles instead of conventional spherical shapes. This asymmetric geometry enables the particles to interlock with each other and with fibers in the fracture, creating a more stable proppant pack that maintains conductivity under high closure stress. The rod shape provides mechanical interlocking capability while the manufacturing process remains relatively simple.
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 resulting rod-shaped proppants interlock with each other and fibers, reducing settling and enhancing porosity and conductivity, thus maintaining well productivity and extending the useful life of the well.
Implementation Method 1
The rod-shaped proppant described in U.S. Pat. No. 8,562,900 is made by extruding a mixture containing alumina-containing materials, a binding agent, a solvent, and other additives such as lubricants and plasticizers through a die.
Implementation Method 2
reducing a length of the stabilized rods by subjecting the stabilized rods to mechanical vibration applied by a device
Implementation Method 3
inducing flow of a slurry comprised of particles and a reactant through one or more orifices and into a coagulation solution, wherein the slurry exiting the one or more orifices is a continuous uninterrupted stream; coagulating the reactant in the coagulation solution to form stabilized rods
Implementation Method 4
subsequently sintering the reduced length stabilized rods
Data Source
AI summary
A method for forming rod-shaped particles includes reducing a length of rods derived from a slurry made up of particles and a reactant, wherein the rods are in a stabilized state in which the reactant has been at least partially reacted with a coagulant, but the rods have not been sintered, and subsequently sintering the reduced length stabilized rods. The reducing the length of the stabilized rods includes subjecting the stabilized rods to mechanical vibration applied by a device, or feeding the stabilized rods through a device having a rotating cutting mechanism.