Flowline saturation pressure measurement
AssigneeSchlumberger Technology Corporation
InventorsKentaro Indo, Maxim Yushko, Tudor Ioan Palaghita, Zeynep Alpman, Alexis Petit, Julian Pop, Sepand Ossia, Tullio Moscato
Life of this patent
Estimating the term…
Abstract
A method for sampling a downhole formation fluid includes pumping formation fluid into the flowline of a downhole sampling tool, measuring a saturation pressure of the formation fluid in the flowline while pumping, and adjusting the pumping rate such that the fluid pressure in the flowline remains within a predetermined threshold above the measured saturation pressure.
Claims15
A method for sampling a downhole formation fluid, the method comprising:
- (a) pumping formation fluid into a flowline of a downhole sampling tool, wherein the flowline is deployed between a fluid inlet probe and a pump;
- (b) measuring a saturation pressure of the formation fluid in the flowline while pumping in (a);
- and
- (c) adjusting a rate of pumping in (a) such that a fluid pressure in the flowline remains within a predetermined threshold above the saturation pressure measured in (b).
A method for sampling a downhole formation fluid, the method comprising:
- (a) pumping formation fluid into a flowline of a downhole sampling tool, wherein the flowline is deployed between a fluid inlet probe and a pump;
- (b) heating formation fluid in the flowline while pumping in (a);
- (c) measuring a temperature of the formation fluid in the flowline while heating in (b);
- (d) evaluating said temperature estimates in (c) to detect whether or not a gas bubble has formed in the flowline;
- (e) increasing a pumping rate in (a) when a gas bubble is not detected in (d);
- (f) determining a temperature indicative of bubble formation when a bubble is detected in (d) and processing a flowline pressure, a reference temperature, the temperature indicative of bubble formation, and a formation fluid model to compute the saturation pressure of the formation fluid at the reference temperature;
- and
- (f) reducing the pumping rate in (a) when the saturation pressure computed in (e) is greater than the flowline pressure.
A downhole formation fluid sampling tool comprising:
- a fluid flowline deployed between a fluid inlet probe and a pump;
- and
- a bubble sensor deployed in the fluid flowline, the bubble sensor including a heating element and a temperature sensor deployed on a common substrate.
Dependencies are inferred from the claim text.