Fiber-Laden Plug Fluid for Wellbore Service Fluid Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for isolating wellbore-service fluids during subterranean well servicing either require adjustment of rheological properties or deployment of special hardware, which can be impractical due to tubular diameter changes and complexity in well operations.
Innovation Solution
A fiber-laden liquid suspension with specific fiber concentrations, lengths, and diameters is used to create a yield stress that maintains separation between fluids, allowing them to flow as a plug without mixing, and is designed to automatically adjust to tubular geometry fluctuations without requiring special equipment or hardware.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If wiper plugs or foam balls are used to isolate fluids, then mixing prevention is improved, but device complexity and operational complexity increase due to special hardware requirements and deployment procedures
Solution Approach 1:
The patent introduces a fiber-laden fluid as an intermediary substance pumped between the first and second wellbore-service fluids. This intermediary fluid contains fibers that form a physical barrier preventing mixing while allowing controlled flow, eliminating the need for complex mechanical devices like wiper plugs or foam balls.
Solution Approach 2:
The patent replaces mechanical isolation devices (wiper plugs, foam balls) with a fluid-based solution containing fibers. The fiber network creates a physical barrier through its rheological properties rather than through mechanical contact, simplifying the system by eliminating special hardware requirements.
2Reliability
If rheological properties of fluids are adjusted to achieve plug flow, then mixing prevention is improved, but fluid formulation complexity increases and may negatively impact other critical fluid performance aspects
Solution Approach 1:
Instead of modifying the rheological properties of the existing wellbore-service fluids, the patent introduces a separate fiber-laden intermediary fluid. This intermediary fluid provides the plug flow characteristics needed for separation while the original fluids maintain their standard formulations and performance characteristics.
Solution Approach 2:
The patent changes the physical state and rheological properties by adding fibers to create a new fluid phase (the fiber-laden intermediary fluid) rather than altering the parameters of the existing fluids. This allows plug flow to be achieved through the intermediary substance without compromising the original fluids' performance.
3Reliability
If pumping rates are reduced to achieve plug flow, then mixing prevention is improved, but productivity decreases due to extended operation time
Solution Approach 1:
The fiber-laden intermediary fluid enables plug flow separation without requiring reduced pumping rates of the main fluids. The intermediary fluid's unique rheological properties allow it to maintain separation effectiveness while the overall pumping operation proceeds at optimal rates for productivity.
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 fiber-laden plug fluid effectively prevents dilution and mixing of wellbore-service fluids, ensuring efficient displacement and separation without altering the rheological properties of the fluids or requiring additional hardware, thus maintaining the integrity of cement slurry and zonal isolation.
Implementation Method 1
The fiber concentration, length and diameter are chosen such that the fiber-laden fluid exhibits yield stress sufficient to flow as a plug. The yield stress arises from fiber entanglement.
Implementation Method 2
The yield stress arises from fiber entanglement. The entanglement may be disrupted by hydrodynamic forces such as those at the entrance of nozzles, but it instantaneously reforms when the forces disappear.
Data Source
AI summary
Fiber laden fluids may be used to separate two wellbore-service fluids as they travel through a tubular body, preventing their commingling. Such fluids obviate the need for mechanical devices such as wiper plugs, or special adjustment of the wellbore-service fluids' rheological properties. The wellbore-service fluids may be drilling fluids, spacer fluids, chemical washes, cement slurries, acidizing fluids, fracturing fluids, formation-consolidation fluids or gravel-pack fluids.