METHODS FOR DETECTING LEAKS IN LIQUID PIPELINES

Abstract

A method for monitoring and detecting leaks in a pipeline is disclosed. The method is particularly useful in pipelines that are transporting hydrocarbons. Gas enabled photo sensitive particles are fed into the pipeline and when they encounter a leak, change their condition. This change is captured by a detector which transmits the data to an operator that a leak condition exists as well as its location and intensity.

Claims

1. A method for detecting a leak in a liquid pipeline comprising feeding gas enabled photo sensitive particles into the liquid pipeline.

2. The method as claimed in claim 1 wherein the liquid is selected from the group consisting of crude oils, petrochemical products, natural gas liquids, monomers, ethylene, diesel, gasoline and jet fuel.

3. The method as claimed in claim 1 wherein the gas enabled photo sensitive particles are particles that surround an inert gas and are surrounded by a surfactant or liquid active system.

4. The method as claimed in claim 3 wherein the particle is a nano-particle or micro-particle.

5. The method as claimed in claim 4 wherein the nano-particle or micro-particle is selected from the group consisting of a silica particle and a zinc oxide particle.

6. The method as claimed in claim 3 wherein the inert gas is selected from the group consisting of nitrogen and argon.

7. The method as claimed in claim 3 wherein the surfactant is selected from the group consisting of sodium dodecyl sulfates, triblock copolymers PEO-PPO-PEO (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)), polyoxyethlene, alkylphenate, polytetrafluoroethylene (PTFE) and OTFE, ethoxylated alcohol, and polyethylene (PEG) surfactants.

8. The method as claimed in claim 1 further comprising a hydrocarbon layer on the surfactant or liquid active system.

9. The method as claimed in claim 3 wherein the gas enabled photo sensitive particle is an oil-gas-oil emulsion.

10. The method as claimed in claim 1 wherein the gas enabled photo sensitive particles change their luminescent state when a leak condition is encountered.

11. The method as claimed in claim 10 wherein a detector detects the change in luminescent state.

12. The method as claimed in claim 11 wherein a detector detects the particles in the liquid thereby establishing a steady state reading.

13. The method as claimed in claim 11 wherein the detector sends the steady state reading and change in luminescent state reading to a supervisory control and data acquisition system.

14. The method as claimed in claim 1 wherein the supervisory control and data acquisition system compares the steady state reading and change in luminescent state reading to calculate if a leak condition is present.

15. The method as claimed in claim 1 wherein the detector is a plurality of detectors mounted periodically along the length of the pipeline.

16. A method for monitoring a liquid pipeline comprising feeding gas enabled photo sensitive particles into the liquid pipeline.

17. The method as claimed in claim 16 wherein the liquid is selected from the group consisting of crude oils, petrochemical products, natural gas liquids, monomers, ethylene, diesel, gasoline and jet fuel.

18. The method as claimed in claim 16 wherein the gas enabled photo sensitive particles are particles that surround an inert gas and are surrounded by a surfactant or liquid active system.

19. The method as claimed in claim 18 wherein the particle is a nano-particle or micro-particle.

20. The method as claimed in claim 19 wherein the nano-particle or micro-particle is selected from the group consisting of a silica particle and a zinc oxide particle.

21. The method as claimed in claim 18 wherein the inert gas is selected from the group consisting of nitrogen and argon.

22. The method as claimed in claim 18 wherein the surfactant is selected from the group consisting of sodium dodecyl sulfates, triblock copolymers PEO-PPO-PEO (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)), polyoxyethlene, alkylphenate, polytetrafluoroethylene (PTFE) and OTFE, ethoxylated alcohol, and polyethylene (PEG) surfactants.

23. The method as claimed in claim 16 further comprising a hydrocarbon layer on the surfactant or liquid active system.

24. The method as claimed in claim 18 wherein the gas enabled photo sensitive particle is an oil-gas-oil emulsion.

25. The method as claimed in claim 16 wherein the gas enabled photo sensitive particles change their luminescent state when a leak condition is encountered.

26. The method as claimed in claim 16 wherein a detector detects the change in luminescent state.

27. The method as claimed in claim 26 wherein a detector detects the particles in the liquid thereby establishing a steady state reading.

28. The method as claimed in claim 27 wherein the detector sends the steady state reading and change in luminescent state reading to a supervisory control and data acquisition system.

29. The method as claimed in claim 16 wherein the supervisory control and data acquisition system compares the steady state reading and change in luminescent state reading to calculate if a leak condition is present.

30. The method as claimed in claim 16 wherein the detector is a plurality of detectors mounted periodically along the length of the pipeline.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is a schematic of a pipeline with an internal leak detection mechanism therein.

[0023] FIG. 2 is a schematic of a pipeline with an array of detectors deployed therein.

[0024] FIG. 3 is a schematic of a pipeline showing the state where particles are quenched and their signal changed.

[0025] FIG. 4 is a cross sectional view of a gas micro-emulsion particle.

[0026] FIG. 5 is a cross sectional view of an inert gas stabilized on micro solid particle.

[0027] FIG. 6 is a schematic representation of the particles in the oil-gas-oil emulsion.

DETAILED DESCRIPTION OF THE INVENTION

[0028] FIG. 1 is a schematic of a pipeline 10 where crude oil 12 is flowing from left to right as indicated by the arrows. The gas enabled photo sensitive particles are labelled P and are present in the crude oil 12 due to a feeding device A. A UV detector D is present in/on the pipeline 10 in order to receive a signal from the gas enabled photo sensitive particles when they encounter a change state, namely a leak condition in the pipeline 10.

[0029] FIG. 2 is a schematic of a pipeline 20 whereby crude oil 22 is flowing from left to right as indicated by the arrows. Device B will introduce the gas enabled photo sensitive particles P into the pipeline 20. These particles will flow with the crude oil 22 and pass by the multitude of sensors D1, D2, D3 and D4 which are spaced apart at intervals to allow for detection of leaks along the length of the pipeline 20.

[0030] FIG. 3 Is a schematic of a pipeline according to FIG. 1 wherein crude oil 12 is flowing through a pipeline 10 along the direction of the arrows. A device is present for feeding the gas enabled photo sensitive particles into the crude oil 12. A UV leak detector D is present inion the pipeline 10 to receive a signal from the gas enabled photo sensitive particles encounter a leak. As seen in FIG. 3, particles denoted as L are present at a leak site within the pipeline 10. The particles will cluster around the leak and since they are encountering a leak condition will change their state and transmit a signal of this changed state to the detector D. The detector will transmit this data to a receiver at a facility overseeing operation of the pipeline and thereby alert an operator that a leak condition is occurring.

[0031] This leak detection method is able to accurate alarm when product is released from the pipeline. The particles involved possess a high enough degree of sensitivity to this product release as well as allow for timely detection thereof. Further this method will allow for the operator to identify the leak location and leak rate to prioritize a response.

[0032] FIG. 4 is a cross sectional representation of one type of gas enabled photo sensitive particle that could be employed in the invention. An inert gas I is surrounded by a hydrocarbon O which when fed to a hydrocarbon system in a pipeline forms an emulsion. This emulsion will allow for the ready delivery of a gas enabled photo sensitive particle to the hydrocarbon in the pipeline as the hydrocarbon O dissolves within the hydrocarbon system in the pipeline.

[0033] FIG. 5 is a cross sectional representation of another type of gas enabled photo sensitive particle that could be employed in the invention. The inert gas I surrounds the particle identified by the dark filled in circle which will be released as gas enabled photo sensitive particle when this system is introduced into the hydrocarbon system in a pipeline.

[0034] FIG. 6 is a cross sectional representation of the oil-gas-oil emulsion as employed in the invention. As indicated the size of the emulsion particle is about 1 micron in diameter. The oil O that is present in the pipeline that is being transported is the primary phase. The gas G is represented by the circles present in the oil O phase. Typically, this is an inert gas such as nitrogen and argon, and this inert gas will be surrounded by the gas enabled photo sensitive particles. The circle(s) within the circles represented by O as well are more of the oil, thereby comprising the oil-gas-oil emulsion which can be used to deliver the gas enabled photo sensitive particles to the pipeline containing the oil.

[0035] Thus, the oil-gas-oil emulsion is for example, a solid nano or micro silica or zinc oxide core particle (the gas enabled photo sensitive particle) that surrounds an inert gas core such as nitrogen or argon gas. The inert gas would contain the oil and the emulsion is completed by the primary phase oil present in the pipeline. The resulting oil-gas-oil emulsion would be aided by surfactants such as non-ionic surfactants

[0036] When this oil-gas-oil emulsion demulsifies, the gas enabled photo sensitive particles will enter the oil phase within the pipeline and will operate to provide information about leaks to the operator of the pipeline.

[0037] While this invention has been described with respect to particular embodiments thereof, it is apparent that numerous other forms and modifications of the invention will be obvious to those skilled in the art. The appended claims in this invention generally should be construed to cover all such obvious forms and modifications which are within the true spirit and scope of the invention.