Balanced Pressure Sampling Flow Line for Reservoir Fluid
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for sampling reservoir fluid often result in contamination of drilling mud, over-pressurization of samples, and high power requirements due to the need to pump fluid against borehole pressure, which complicates the sampling process and can lead to unstable pressure-volume-temperature environments.
Innovation Solution
A method and apparatus that utilize a flow line with inlet and outlet ports to circulate fluid within the formation, avoiding discharge into the borehole and allowing sampling against formation pressure, thereby minimizing pressure differential and reducing contamination and power needs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If fluid is pumped into the sample chamber against borehole pressure, then the sample chamber can be filled with reservoir fluid, but the sample becomes over-pressured creating an unstable PVT environment
Solution Approach 1:
Instead of pumping fluid into the sample chamber against borehole pressure, the invention reverses the approach by allowing fluid to enter the sample chamber through the outlet port where formation pressure naturally drives the fluid flow. This eliminates the need to overcome borehole pressure and prevents over-pressurization of the sample.
2Productivity
If a higher pressure differential is provided to pump sample into the downhole tool, then sampling can be achieved, but additional power is required
Solution Approach 1:
The system uses the natural formation pressure differential to drive fluid into the sample chamber without requiring additional pumping power. The formation pressure itself performs the work of pushing fluid through the inlet port and into the sample chamber, making the system self-servicing in terms of pressure generation.
3Ease of operation
If fluid is discharged into the borehole during cleanup, then mud filtrate can be purged from the flow line, but reservoir fluid contaminates the drilling mud
Solution Approach 1:
The invention extracts the harmful discharge operation by providing a separate outlet port that allows fluid to be discharged directly into the formation rather than into the borehole. This separates the cleanup function from the contamination problem, enabling effective purging without compromising drilling mud quality.
4Stress or pressure
If the backside of the piston is exposed to borehole pressure, then the sample chamber can be pressurized, but the pressure differential from sample to formation is increased
Solution Approach 1:
The invention creates equipotential conditions by exposing the backside of the piston to formation pressure through the outlet port rather than borehole pressure. This equalizes the pressure environment between the sample chamber and the formation, eliminating excessive pressure differentials and creating a stable PVT environment for the sample.
Data Source
AI summary
A method of sampling fluid from a rock formation penetrated by a borehole includes positioning a downhole tool having a flow line in the borehole, establishing an inlet port through which fluid passes from a first point in the formation into the flow line, establishing an outlet port through which fluid passes from the flow line into a second point in the formation, and passing fluid between the formation and the flow line through the inlet and outlet ports.