Microfracture Conductivity via Proppant and ASMA
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Low permeability subterranean formations, such as shale reservoirs and tight-gas sands, require enhanced fracture complexity to improve fluid conductivity, but existing methods like acidizing are limited by acid spending and leak-off, which can reduce the effectiveness of fracture complexity enhancement.
Innovation Solution
A combination of micro-proppant and macro-proppant with an aqueous-based surface modification agent (ASMA) is used to enhance microfracture conductivity, where micro-proppant enters microfractures and macro-proppant enters macrofractures, with the ASMA forming a tacky film to facilitate attachment and increase permeability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If acidizing is used to enhance fracture complexity and conductivity, then microfracture conductivity is improved, but acid spending and leak-off reduce treatment effectiveness
Solution Approach 1:
The patent introduces proppant particulates as an intermediary carrier that delivers the acid treatment to the fracture zones. The proppant particles are injected with the acid fluid, allowing the acid to be transported and deposited in the fractures without requiring the acid to travel through the entire wellbore, thereby reducing acid spending and leak-off losses while maintaining effective fracture conductivity enhancement.
Solution Approach 2:
The patent changes the physical state and delivery mechanism of the acid treatment by incorporating it into a proppant slurry system. This parameter change allows the acid to be delivered in a controlled manner with the proppant, reducing uncontrolled leak-off and spending while maintaining the chemical etching effect on the formation to enhance fracture conductivity.
2Reliability
If multiple interval acidizing treatments are performed to maximize fracture complexity, then conductivity is enhanced, but acid spending increases and reduces effectiveness in later intervals
Solution Approach 1:
The patent divides the treatment into discrete proppant-injected intervals, where each interval receives a targeted amount of acid carried by proppant particles. This segmentation allows precise control of acid placement in each zone, preventing acid from one interval from being consumed before reaching subsequent intervals, thereby enabling effective multi-interval treatment with optimized acid volume distribution.
Solution Approach 2:
The patent performs preliminary proppant placement to establish fracture conduits before injecting the acid-carrying proppant slurry. This preliminary action creates defined pathways that guide the acid to the intended zones, ensuring that subsequent acidizing treatments in multiple intervals are delivered efficiently without excessive acid spending or premature depletion.
3Reliability
If proppant particulates are used to keep fractures open, then fracture conductivity is maintained, but microfracture conductivity is insufficient without additional enhancement
Solution Approach 1:
The patent merges two functions into a single treatment step: proppant placement for fracture support and acidizing for microfracture enhancement. By combining proppant particulates with acid fluid in a slurry system, the treatment simultaneously maintains fracture openness and creates dendritic microfracture networks, achieving both macro and micro-scale conductivity improvement in one operation.
Solution Approach 2:
The patent uses a composite treatment fluid system consisting of proppant particulates suspended in acid-containing carrier fluid. This composite material delivers both the mechanical support function of proppant and the chemical enhancement function of acid, creating a synergistic effect that improves both fracture conductivity and microfracture complexity simultaneously.
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 significantly increases the permeability of complex fracture networks, allowing greater fluid flow and enhancing production by forming a partial monolayer and mini-pillars that support fracture conductivity, even in low permeability formations.
Implementation Method 1
an aqueous-based surface modification agent... forming a tacky film to facilitate attachment
Implementation Method 2
The degree of success of a stimulation operation depends, at least in part, upon the porosity of the proppant pack to permit the flow of fluids through the interconnected interstitial spaces between abutting proppant particulates
Implementation Method 3
injecting an acid (e.g., hydrochloric acid) into a subterranean formation in order to etch channels or create microfractures
Data Source
AI summary
Methods comprising: introducing a micro-proppant treatment fluid into a formation at a rate and pressure sufficient to create or enhance at least one fracture in a first treatment interval, wherein the micro-proppant treatment fluid comprises a first aqueous base fluid, micro-proppant particulates, and a first aqueous-based surface modification agent (“ASMA”); placing the micro-proppant particulates into the at least one fracture; introducing a surface modification treatment fluid into the subterranean formation, wherein the surface modification treatment fluid comprises a second aqueous base fluid and a second ASMA; coating at least a portion of a face of the at least one fracture with the second ASMA; introducing a macro-proppant treatment fluid into the subterranean formation, wherein the macro-proppant treatment fluid comprises a third base fluid and macro-proppant particulates; and placing the macro-proppant particulates into the at least one fracture.