Low-Density Proppant Particulates from Polyaromatic Hydrocarbons
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fracturing operations face challenges with the deposition of proppant particulates in fractures due to their high density, which hinders transport and leads to decreased fracture conductivity, and the use of polymer gels can cause formation damage if not fully broken down.
Innovation Solution
The development of low-density, high-crush-strength proppant particulates formed from crosslinked polyaromatic hydrocarbons and a crosslinking agent, which are synthesized as substantially spherical particles using an acid-catalyzed reaction in an aqueous solvent, allowing for in situ formation and reducing the need for gelled polymers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If proppant particulates with high density are used, then they can effectively keep fractures open, but their transport into remote reaches of fractures becomes difficult
Solution Approach 1:
The patent changes the density parameter of proppant particulates by using low-density materials such as expanded perlite, expanded vermiculite, or polymer beads instead of traditional high-density materials like sand or ceramic. This parameter change enables effective transport into remote fracture reaches while maintaining fracture support capability through the use of crosslinked polyaromatic hydrocarbons that provide structural integrity.
Solution Approach 2:
The patent employs composite materials by combining low-density expandable cores (perlite, vermiculite) with crosslinked polyaromatic hydrocarbon shells. This composite structure achieves both low density for easy transport and high strength for effective fracture support, resolving the contradiction between transportability and fracture support capability.
2Productivity
If polymer gels are used to promote effective transport of proppant particulates, then transport efficiency improves, but formation damage occurs if the gels do not completely break
Solution Approach 1:
The patent extracts or eliminates the polymer gel component from the fracturing system by using low-density proppant particulates that can be transported effectively without gel assistance. This removal of the gel eliminates the harmful effect of incomplete gel breakdown while maintaining transport efficiency through the low-density nature of the proppant materials.
Solution Approach 2:
The patent uses biodegradable or easily degradable low-density proppant materials that serve their purpose temporarily during transport and then naturally break down or remain inert in the formation, replacing the need for polymer gels that require complete breakdown. This approach avoids formation damage while maintaining transport functionality.
3Strength
If proppant particulates are crushed within the wellbore, then fines are produced, but fluid conductivity decreases and production rates are reduced
Solution Approach 1:
The patent changes the mechanical strength parameter of proppant particulates by using crosslinked polyaromatic hydrocarbons with high crush strength. This parameter change prevents particulate crushing during wellbore transport, thereby preventing fines production and maintaining fluid conductivity and production rates.
Solution Approach 2:
The patent provides beforehand cushioning against crushing forces by designing proppant particulates with inherently high crush strength through crosslinking. This pre-engineered strength protection prevents crushing before it can occur during wellbore transport, eliminating the harmful effect of fines production on fluid conductivity.
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 enables effective transport and deposition of proppant particulates within fractures, maintaining conductivity and preventing formation damage by reducing the reliance on polymer gels and utilizing low-cost, high-aromaticity refinery streams.
Implementation Method 1
The crosslinking agent comprises at least two functional groups that are reactive under acid-catalyzed conditions with an aromatic ring of the polyaromatic hydrocarbon
Implementation Method 2
reacting a polyaromatic hydrocarbon with a crosslinking agent in the presence of an acid catalyst and a surfactant in an aqueous solvent, and forming substantially spherical particulates in situ in the aqueous solvent
Data Source
AI summary
Proppant particulates are commonly used in hydraulic fracturing operations to maintain one or more fractures in an opened state following the release of hydraulic pressure. In complex fracture networks, it can be difficult to deposit proppant particulates fully within the fractures. In addition, low crush strengths may result in problematic fines formation. Polyaromatic hydrocarbons, commonly encountered in various refinery process streams, may serve as an advantageous precursor to proppant particulates. Polyaromatic hydrocarbons may undergo crosslinking under acid-catalyzed conditions in an aqueous solvent in the presence of a surfactant to form substantially spherical particulates that may serve as effective proppant particulates during fracturing operations. In situ formation of the proppant particulates may take place in some cases.