Joint Industry Project
PEA74: Proppant Flowback Study
The aim of this project is to develop guidelines for avoiding proppant flowback. Testing takes place on a test cell that has been developed in-house at Fractech and which recreates field conditions as accurately as possible within realistic constraints.
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| FracTech's Proppant Flowback Test-Cell | |||||||||||
Applications by Well Type: |
(clicking on these links will jump to the relevant section ) |
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All | |
Cyclic |
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High Temperature | |
Water Cut |
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Low Temperature | |
High-rate Gas |
All Wells |
(clicking on these links will jump to the relevant sub-section
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Heat Transfer | |
Soft Formations |
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Contingency | |
Resin Detachment |
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Erosion |
Heat Transfer
A tool is being developed for:
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Correctly matching the field heat up in the laboratory and hence to properly identify and evaluate issues for high temperature applications (for example, partial curing of the resin before closure is achieved). |
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Aiding fluid stability design for fracturing treatments (for example breaker loading) and provide recommendations for minimum shut-in times to achieve sufficient resin bond strength to enable the well to be brought back on to production post fracture. |
Soft Formations
A database of results is to be established showing:| |
Conductivity impairment |
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Sand control |
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Embedment using fibres, rcp and non-rcp systems in unconsolidated sands. |
Industry Guidelines and Information Management
A set of industry guidelines and methods are being drafted to provide more effective utilisation of the data generated within the project and the experience and lessons learned in the field.The guidelines cover the following applications:
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Low Shut-in Closure Stress | |
Fracturing Fluid pH |
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High Shut-in Closure Stress | |
Breaker Loadings |
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High Effective Stress During Production | |
Shut-in Time |
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Low Reservoir Temperature | |
Production Rates |
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High Reservoir Temperature | |
Production Fluids |
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Fracture Width | |
Stress Cycling During Production |
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Treatment Injection Rate |
Resin Detachment
FracTech have identified this mechanism as a means of pack failure and have
isolated those product types which are affected. The current phase of the project
will investigate the causes and consequences of this phenomenon.
An experimental product, developed to overcome this failure mechanism has been tested.
Contingency
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Fluid compatibility issues identified by a participating operator will be investigated. |
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Identification of factors associated with stable molehole production utilising fibres plus resin coated proppants to be established. |
Erosion
The identification of factors associated with erosion due to differences in proppant shape / material / density are being studied.
Curing Stress Impact on Conductivity
Higher closure stress during curing of rcp promotes tighter packing and lower permeability.
Much rcp conductivity is referenced to 1000psi curing stress although higher initial shut-in conditions exist in the field. For example, a pack cured at 5000psi will have 40% less conductivity at 8000psi than a pack cured at 1000psi.
FracTech have conducted tests in order to determine the effects on the permeability of proppant packs at elevated curing stresses. Trend analysis for specified products will be issued as part of the current phase of work.
Breaker Adsorption by Resin Coated Proppant Slurries
Breaker adsorption tests have been conducted on a range of different resin-coated products at both 60 and 90 degrees Celsius.
High Temperature Wells
Heat Transfer
Under development is a tool for:
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Correctly matching the field heat up in the laboratory and hence to properly identify and evaluate issues for high temperature applications (for example, partial curing of the resin before closure is achieved). |
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Aiding fluid stability design for fracturing treatments (for example breaker loading) and provide recommendations for minimum shut-in times to achieve sufficient resin bond strength to enable the well to be brought back on to production post fracture. |
Resin Detachment
FracTech have identified this mechanism as a means of pack failure and which products are affected. The current phase of the project will investigate the causes and consequences of this phenomenon.
An experimental product, developed to overcome this failure mechanism, has been tested.
Fibres
Tests have been performed to determine the effectiveness of fibres used in conjunction with rcp to overcome the effects of resin detachment. These were conducted at RWE-DEA conditions (i.e. high temperature, high pressure & stress cycling).
Also investigated was the use of fibres with uncoated proppant to produce stable, high conductivity moleholes.
Industry Guidelines and Information Management
A set of industry guidelines and methods are being drafted to provide more effective utilisation of the data generated within the project and the experience and lessons learned in the field.
High temperature applications are covered in the current version of FracTech's industry guidelines.
Low Temperature Wells
Heat Transfer
Under development is a tool for:
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Correctly matching the field heat up in the laboratory and hence to properly identify and evaluate issues for low temperature applications. |
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Aid fluid stability design for fracturing treatments (for example breaker loading) and provide recommendations for minimum shut-in times to achieve sufficient resin bond strength to enable the well to be brought back on to production post fracture. |
Fibres
The use of fibres with uncoated proppant to produce stable, high conductivity moleholes has been investigated. Such systems would be applicable to low temperature reservoirs where curing of resin coated proppants may prove problematic.
Field data performance may be collated and critically assessed.
New Technology
A continuation of the deformable bead tests, specifically, higher loadings for wider packs, percentage requirements in 20/40, and comparison of their performance relative to the inclusion of a similar sized non-deforming particle (as a baseline).
The determination of minimum shut-in time and drillability issues of Low Temperature products will be assessed in the current phase.
Industry Guidelines and Information Management
A set of industry guidelines and methods are being drafted to provide more effective utilisation of the data generated within the project and the experience and lessons learned in the field.
Low temperature applications are covered in the current version of FracTech's industry guidelines.
Cyclic Wells
Proppant Flowback Evaluation Testing
Numerous products have been flowback tested with stress cycling, under various well conditions. Standard practice is to test to 30 cycles or pack failure.
Extended Time
The issue of extended cycling has been highlighted by a number of operators. Thus, during the current phase, systems are being tested through hundreds rather than tens of cycles.
This work will be run on one of the two flowback cells in which a servo-pump will automatically ramp the pack through stress cycles with data logging of the pack compression and expansion.
Water Cut Wells
COMING SOON
High Gas RateWells
COMING SOON
Costs
The membership fee is available on application (for current phase)
Current Membership
The project is supported by all primary resin manufacturers, BJ Services and Schlumberger. In addition, it enjoys key support from oil companies globally.