Zonal Compositional Flow Rate Measurement in Commingled Gas Wells
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current downhole fluid analysis (DFA) tools are limited by their size and inability to measure fluid flow rates and compositions in real-time across multiple depths within production logging environments, especially in flowing wells where pressure seals are challenging to maintain.
Innovation Solution
A production logging tool (PLT) is designed to be conveyed within tubing to measure flow rates and compositional components of zonal fluid flows at multiple depths, using modules for spectroscopy and flow rate measurement, and a controller to determine zonal fluid flow rates and compositional component flow rates based on measured data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If downhole fluid analysis tools are used to measure fluid composition, then compositional characterization is improved, but the tool diameter and cable size increase making it incompatible with some production logging environments
Solution Approach 1:
The patent extracts the fluid sampling function from the main tool body by using a separate sampling probe that extends through the tubing. This allows the main tool to remain compact while still performing compositional analysis by drawing fluid samples through the probe to external sensors.
Solution Approach 2:
The patent introduces a sampling probe as an intermediary element between the production tubing and the analysis sensors. This probe allows fluid to be extracted from the flowing well without requiring the entire tool to be large enough to form a seal around the tubing, thus maintaining small tool dimensions while enabling compositional measurement.
2Measurement precision
If open-hole and cased-hole sampling tools form a seal around borehole wall or casing perforations, then fluid sampling is improved, but the tools cannot be used in production logging environments with flowing wells
Solution Approach 1:
The sampling probe acts as an intermediary that extends through the production tubing to reach the flowing fluid. This allows the tool to sample fluid in production logging environments without requiring a seal around the tubing, unlike traditional open-hole and cased-hole tools. The probe enables fluid extraction while maintaining compatibility with flowing well conditions.
Solution Approach 2:
Instead of forming a seal around the borehole wall or casing as traditional tools do, this invention inverts the approach by using a probe that passes through the tubing to access the flowing fluid. This reversal of the sealing concept allows the tool to function in production logging environments where maintaining a pressure seal on flowing wells is challenging.
3Reliability
If a larger diameter cable is used to convey DFA tools, then pressure sealing capability is improved, but the cable cannot be accommodated while maintaining a pressure seal on a flowing well
Solution Approach 1:
The patent extracts the pressure sealing function from the cable by using a sampling probe that passes through the tubing. This eliminates the need for a large-diameter cable to maintain a pressure seal, as the probe itself can be made small enough to accommodate in flowing wells while still enabling fluid sampling and compositional analysis.
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, real-time determination of zonal fluid flow rates and compositional components across multiple depths, optimizing well management by identifying rich or lean zones and minimizing unwanted gas production.
Implementation Method 1
operating the tool to measure a flow rate of the fluid flow at each of multiple depths
Implementation Method 2
operating the tool to measure proportions of compositional components of the fluid flow at each of the zone-associated depths
Data Source
AI summary
A production logging tool (PLT) is conveyed within production tubing containing production fluid flow established by zonal fluid flow from formation zones. The PLT measures a flow rate of the production fluid flow at each of a plurality of depths associated with a corresponding one of the zones. A flow rate of the zonal fluid flow from each zone is determined based on the flow rates of the production fluid flow measured at each of the depths. The PLT measures proportions of compositional components of the production fluid flow at each of the depths. A flow rate of each compositional component of the zonal fluid flow from each zone is determined based on the determined flow rate of the zonal fluid flow from each zone and the proportions of compositional components of the production fluid flow measured at each of the depths.