Chelating Agent Soaking Process for Subterranean Formation Treatment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Subterranean formations with low reactivity to treatment compositions often result in compositions being trapped near the wellbore, leading to reduced permeability increases, rock strength reduction, and increased risk of fracturing, as existing processes fail to effectively penetrate and react with the formation.
Innovation Solution
A process involving the introduction of a composition containing chelating agents like glutamic acid N,N-diacetic acid or its salts, with a soaking step where the flow rate is intentionally decreased and then increased, allowing for selective dissolution of narrow pore throats and improved permeability-to-porosity ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the flow rate of treatment composition is increased to improve penetration into the formation, then the composition can reach deeper areas, but the reaction time with formation materials is reduced and permeability increase is limited
Solution Approach 1:
The patent applies periodic action by implementing a multi-stage flow regime: an initial high flow rate stage for rapid composition delivery and formation penetration, followed by a low flow rate soaking stage for extended reaction time, and finally a second high flow rate stage for enhanced permeability. This periodic variation in flow rate resolves the contradiction between speed and reaction time by providing both rapid transport and sufficient contact time at different stages of the treatment process.
2Productivity
If the composition is introduced at high concentration to enhance reaction effectiveness, then the treatment efficiency improves, but the risk of rock strength reduction and fracturing increases
Solution Approach 1:
The patent applies dynamics by making the treatment process adaptive through flow rate modulation. The system dynamically adjusts flow rate based on treatment stage: high flow rate initially to deliver concentrated composition efficiently, then transitions to low flow rate during soaking to maintain effectiveness while reducing mechanical stress on the rock, and finally increases flow rate again for permeability enhancement. This dynamic approach resolves the contradiction between treatment efficiency and rock strength preservation.
3Manufacturing precision
If the soaking time is extended to improve dissolution of narrow pore throats, then the permeability-to-porosity ratio improves, but the treatment time and operational duration increase
Solution Approach 1:
The patent resolves this contradiction through periodic action with a structured multi-stage process. The soaking stage with extended low flow rate is embedded within a larger periodic cycle that includes high flow rate stages. This allows the system to achieve extended reaction time for improved permeability-to-porosity ratio while maintaining overall treatment efficiency through the alternating high-flow stages that rapidly deliver composition and later enhance permeability, thus minimizing total operational duration.
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 achieves a more favorable permeability increase while minimizing rock strength reduction and fracturing risks, with the soaking step enabling a more selective and effective reaction with the formation, even in formations with low dissolution rates.
Implementation Method 1
the composition is reacted with a formation... selective dissolution of narrow pore throats... permeability increase
Data Source
AI summary
The present invention relatestoa process to treat a subterranean formation by introducing a composition containing between 1 and 40 wt% on total weight of the composition of a chelating agent selected from the group of glutamic acid N,N- diacetic acid or a salt thereof (GLDA), aspartic acid N,N-diacetic acid or a salt thereof (ASDA), and methylglycine N,N-diacetic acid or a salt thereof (MGDA) into the formation, wherein the process comprises a soaking step.