Targeted Tracer Injection With Online Detection for Multiphase Well Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for multi-phase petroleum well flow characterization are inefficient in determining the inflow distribution of target fluids, as they fail to accurately measure the arrival times and slip velocities of tracers in complex fluid mixtures, leading to inaccurate flow regime analysis.
Innovation Solution
A method involving simultaneous injection of water-affine and hydrocarbon-affine tracers at multiple locations along the well, followed by optical detection and calculation of slip times, allowing for precise characterization of fluid flow behavior and inflow distribution using a synchronized injection system and online detection probes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional tracer injection methods are used in multi-phase petroleum wells, then the system structure is simple, but the measurement precision of arrival times and slip velocities is insufficient
Solution Approach 1:
The injection system is divided into multiple independent injection devices positioned at different locations along the wellbore. Each device can independently inject tracers into specific phases (water, oil, gas), enabling precise tracking of individual phase movement and improving arrival time measurement precision without requiring a monolithic complex system
Solution Approach 2:
Tracers are pre-mixed with carrier fluids in reservoirs before injection. The injection devices are pre-positioned at specific depths along the wellbore, and the system is pre-configured to inject into specific phases. This preliminary preparation enables accurate tracking of phase movement and slip velocity calculation without requiring complex real-time adjustments
2Loss of information
If tracers are injected into complex fluid mixtures, then flow characterization data can be obtained, but the detection accuracy of tracer arrival times deteriorates due to mixing effects
Solution Approach 1:
Different tracers with distinct optical properties are assigned to different fluid phases (water-affine tracers for water phase, hydrocarbon-affine tracers for oil/gas phases). This local differentiation enables the detection system to distinguish between phases and accurately detect tracer arrival times even in complex multi-phase mixtures, preventing information loss
Solution Approach 2:
The invention uses tracers with different optical characteristics (fluorescence, absorption, scattering properties) that can be detected by optical sensors. These optical properties act as phase identifiers, allowing the detection system to distinguish tracers from different phases and maintain detection accuracy in complex fluid mixtures
3Measurement precision
If simultaneous injection of multiple tracers is performed, then flow regime analysis precision is improved, but the device complexity increases
Solution Approach 1:
Multiple injection devices are integrated into a single coordinated system that can simultaneously inject different tracers into different phases. The devices share common control logic and synchronization mechanisms, enabling precise flow regime analysis through multi-tracer injection without requiring entirely separate independent systems for each tracer
4Productivity
If online detection probes are used for tracer detection, then the productivity of flow characterization is improved, but the device complexity increases
Solution Approach 1:
The invention replaces complex mechanical sampling and laboratory analysis systems with optical detection probes that can measure tracer concentrations in-situ in real-time. This substitution dramatically improves flow characterization productivity by providing continuous data without requiring physical fluid extraction and laboratory processing
Solution Approach 2:
The detection probes are designed to be self-contained units that can be deployed downhole and autonomously detect tracer arrivals. The system performs self-diagnosis and data processing, reducing the need for complex external support equipment and personnel intervention, thereby improving 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
Enables accurate determination of fluid flow regimes and inflow distribution by ensuring rapid mixing and detection of tracers, providing high-resolution data for flow characterization and improving the understanding of multi-phase well behavior.
Implementation Method 1
a light source for generating light capable of generating luminescent light in the tracers—one or more optical fibres through the sensor body for guiding the light to and through the windows into the flow, one or more optical fibres through the sensor body for receiving backscattered luminescence arriving 'back' through the window and guiding the light to a luminescence detector
Implementation Method 2
one or more optical fibres through the sensor body for guiding the light to and through the windows into the flow, one or more optical fibres through the sensor body for receiving backscattered luminescence
Data Source
AI summary
The invention is a method, a system, tools for use by the system, and an interpretation method for injecting and detecting tracers and conducting flow characterizing of a petroleum well. The method describes monitoring of travel time and slip velocity between two/three different phases (oil/water and possibly gas) in the well. The travel time and slip velocity are determined using an injection too for injection of an over pressurized injection of the partitioning tracers each of which would follow certain phase. The tracers are detected by an optical detection probe in the pipe. The slip velocity is obtained from the difference of travel time of two tracers which partition to two different phases.