Compressed natural gas system with gas distributer

Abstract

A compressed natural gas system includes a pressurized natural gas source and a gas distributer. The gas distributer includes a natural gas plenum, an inlet port leading into the natural gas plenum, and a plurality of outlet ports each leading out of the natural gas plenum. Each of the outlet ports includes a first connector that is configured to be coupled in a gas-tight connection to a second connector that is on a gas supply line.

Description

COMPRESSED NATURAL GAS SYSTEM WITH GAS DISTRIBUTERCROSS-REFERENCE TO RELATED APPLICATION

[0001] The present disclosure claims the benefit of United States Provisional PatentApplication No. 63 / 586,452, filed September 29, 2023.BACKGROUND

[0002] In a hydraulic fracturing operation, pumps are used to inject fracking fluid down a wellbore in order to assist with fracturing of rock formations. The pumps have traditionally been diesel fuel powered, but more recently pumping has been conducted with electrically powered pumps. Turbine generators at the site combust natural gas to produce the necessary electrical power to run the pumps. Compressed natural gas is delivered to the site in large tanks, which allows maximum amounts of the natural gas to be delivered. The initial pressure of the compressed natural gas, however, is much higher than the desired input pressure into the turbine generators. The natural gas from the delivery tanks is therefore run through a pressure reduction system to reduce the pressure and produce “treated” compressed natural gas that is at the desired input pressure (and temperature) for the turbine generators.SUMMARY

[0003] A compressed natural gas system includes a pressurized natural gas source and a gas distributer. The gas distributer includes a natural gas plenum, an inlet port leading into the natural gas plenum, and a plurality of outlet ports each lead out of the natural gas plenum. Each of the outlet ports is configured to be coupled in a gas-tight connection to a gas supply line to a piece of equipment that is to be provided with compressed natural gas.

[0004] The present disclosure may include any one or more of the individual features disclosed above and / or below alone or in any combination thereof.BRIEF DESCRIPTION OF THE DRAWINGS

[0001] The various features and advantages of the present disclosure will become apparent to those skilled in the art from the following detailed description. In this disclosure, like reference numerals designate like elements where appropriate and reference numerals with the addition of one-hundred or multiples thereof designate modified elements that are understood to incorporate the same features and benefits of the corresponding elements. The drawings that accompany the detailed description can be briefly described as follows.

[0002] Figure 1 illustrates a compressed natural gas system.

[0003] Figure 2 illustrates a gas distributer of the system.

[0004] Figure 3 illustrates a pipe section of the distributer.

[0005] Figure 4 illustrates connections made during an assembly of the system.DETAILED DESCRIPTION

[0006] Figure 1 schematically illustrates an example of a compressed natural gas system 20. For example, the system 20 is configured to deliver treated natural gas to equipment on a gas / oil well site, such as turbine generators at a hydraulic fracturing operation. As used herein, “treated natural gas” refers to natural gas that has undergone a controlled pressure reduction from an initial relatively high pressure to a lower, target pressure and temperature for input into the downstream equipment. The system 20 is also considered to be mobile in that it can be readily deconstructed, moved from one site to another site, and then readily reconstructed for operation to deliver and distribute compressed natural gas. Thus, the system 20 will typically not include any permanent structures, such as buildings that stand permanently in one place.

[0007] In the example shown, the system 20 involves a pressurized natural gas source 22, a gas distributer 24, and multiple pieces of equipment 26 to which compressed natural gas is to be delivered. It is to be appreciated that the equipment 26 is shown in order to demonstrate an example configuration and operation of the system 20, and the equipment 26 may or may not be considered to be a part of the system 20. The pressurized natural gas source 22 is any source of natural gas that has a pressure and temperature that meets pressure and temperature targets for use in the equipment 26. In one example, the pressurized natural gas source 22 is a pressure reduction system. Pressure reduction systems are known in the art as systems that include multiple stages of controlled, progressive pressure reductions and temperature manipulations in order to take high pressure input natural gas and provide an output of natural gas that is controlled to a pressure and temperature that that meets pressure and temperature targets for use in the equipment 26. The treated compressed natural gas from the pressure reduction system is then output through one or more gas feed lines 27 to the gas distributer 24. Though not usually the case, insofar as compressed natural gas can be delivered to the system 20 from a storage of compressed natural gas that is already at the target pressure and temperature without treatment in a pressure reduction system, such a storage of compressed natural gas may alternatively be used as the source 22. The gas distributer 24 serves to supply the compressed natural gas through gas supply lines 36 to the multiple pieces of equipment 26,e.g., turbine generators. In one example, the lines 27 / 36 are hoses that are rated for transferring natural gas and rated for the applicable pressures that the gas will be at in the system 20. The hoses may also have additional properties to be better suited to a given implementation of the system 20, such as but not limited to, flexibility, temperature durability, and chemical resistance. The hoses, plenum 28, and other components of the system 20 should also meet any applicable codes and / or site regulations for handling and / or delivering compressed natural gas, which a person of ordinary skill in the art will be aware of.

[0008] Figure 2 illustrates selected portions of the gas distributer 24, and a representative view of one of the pipe sections 30 in Figure 2 is shown in Figure 3. The gas distributer 24 includes a natural gas plenum 28. In this example, the natural gas plenum 28 includes a plurality of pipe sections 30 that are attached end-to-end, such as at bolted flange joints. Seals may be provided in the joints to facilitate gas-tight sealing. In this example, the pipe sections 30 are straight and cylindrical (circular in cross-section), though they alternatively could be curved, include bends or elbows, or have other cross-sectional shapes in order to adapt the “footprint” of the distributor 24. However, straight, cylindrical pipe sections may provide better access to the attachment joints for constructing and deconstructing the gas distributer 24, in comparison to curved or elbowed configurations that could spatially hinder access to those joints, and cylindrical piping is usually readily available. Three such pipe sections 30 are shown in Figure 2, though the natural gas plenum 28 can alternatively have fewer pipe sections 30 or additional pipe sections 30, depending on how many pieces of equipment 26 natural gas is to be delivered to.

[0009] The plenum 28 refers to a passage 31 running through the pipe sections 30 which, via the attachment joints, is fluidly continuous across the string of pipe sections 30. The ends of the first and last pipe section in the string are, at least initially, open, and one such open end may serve as an inlet port 32 that leads into the passage 31 inside of the pipe sections 30, i.e., the natural gas plenum 28. The other of the open ends may be capped off such that the passage 31 provides a gas-tight volume for the treated compressed natural gas. The inlet port 32 may be configured with a connector 32a, such as a quick connect or dry connect in order to facilitate connection to the gas feed line 27 from the pressure reduction system.

[0010] Each of the pipe sections 30 includes one or more outlet ports 34. For example, the outlet ports 34 may be pipe stubs or elbowed fittings. In general, the ports 34 are smaller than the passage 31. For instance, each of the pipe sections 30 has a first (inside) diameter DI and each of the outlet ports 34 has a second (inside) diameter D2 that is smallerthan DI . Each of the outlet ports 34 includes a connector 34a that is configured to be connected in a gas-tight connection to a mating connector 36a on each of the gas supply lines 36.

[0011] In the example shown, each of the outlet ports 34 extends perpendicularly to the length direction of the pipe sections 30. For example, the pipe sections 30 are arranged along a central axis of the passage 31, and the outlet ports 34 are arranged along central port axes that are approximately perpendicular to the central axis of the passage 31. Such a configuration permits the gas distributer 24 to be arranged along the side of a bank of the equipment 26 or along a region designated for compressed natural gas filling of equipment, with the outlet ports 34 facing toward the equipment 26 or region to reduce the length of the gas supply lines 36 that is needed to reach the equipment 26.

[0012] As further shown in Figure 3, the system 20 additionally includes support stands 38 that each have support legs 38a / 38b that are mounted on a web portion that forms a cradle section 40 into which the pipe sections 30 nest for support. The pipe sections 30 may be secured with the support stands using U-bolts or other type of fastener. In the example shown, there are two support stands 38 per each pipe section 30, with one support stand 38 arranged toward each end of the pipe section 30. Additional support stands 38 may be used for longer span pipe sections or if greater support is desired. The support stands 38 hold the natural gas plenum 28 at an elevated height (h) off of a surface S on which the support legs 38a / 38b are set, such as the ground. This serves to keep the gas distributer 24 off of the ground, at least clear of direct contact with dirt, debris, and ground moisture. Additionally, the elevation provided by the stands 38 allows one or more of the lines 27 / 36 to pass under the pipe sections 30 if desired.

[0013] Figure 4 shows several views of selected portions of the system 20. The system 20, along with the disclosure above, also represents a method of assembling the system 20 to provide compressed natural gas. For example, the method may be employed in connection with a startup or rigging up of a well site for a hydraulic fracturing operation, or in reverse in connection with a shutdown or rigging down of the well site. As shown in view (a), the method includes fluidly connecting the gas feed line 27 to an outlet 22a of a pressure source 22. In view (b), the other end of the gas feed line 27 is fluidly connected to the connector 32a of the inlet port 32 of the plenum 28. Also in view (b), an end of the gas supply line 36 with connector 36a is fluidly connected to the connector 34a of one of the outlet ports 34 of the plenum 28. Finally, in view (c) the other end of each of the gas supply lines 36 is connected to one of the pieces of equipment 26. It is to be appreciated that the order of performing these connections (or disconnections) may be varied.

[0014] The system 20, along with the disclosure above, also represents a method for supplying compressed natural gas. For example, the method includes, in a pressure reduction system, reducing a pressure of an input compressed natural gas from a first pressure to a second pressure to produce treated compressed natural gas at an outlet 22a of the source 22. The treated compressed natural gas from the outlet 22a is then fed through the gas feed line 27 to the inlet port 32 and then into the natural gas plenum 28 of the gas distributer 24. The gas distributer 24 feeds the treated compressed natural gas through the gas supply lines 36 connected to outlet ports 34 of the natural gas plenum 28, and the gas supply lines 36 deliver the treated compressed natural gas to the equipment 26. Thus, all of the treated compressed natural gas is delivered through the plenum 28, the volume of which may also serve as a pressure equalizer and / or a temperature equalizer in the event that there are transient pressure and temperature fluctuations in the treated compressed natural gas form the source 22. For instance, insofar as the treated compressed natural gas experiences a transient pressure and / or temperature fluctuation coming out of the source 22, that gas is mixed with gas that is already in the plenum 28, thereby mitigating the transients as the mixed gas equilibrates in pressure and temperature in the plenum 28.

[0015] Although a combination of features is shown in the illustrated examples, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the Figures or all of the portions schematically shown in the Figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments.

[0016] The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from this disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims.

Claims

CLAIMSWhat is claimed is:1 . A compressed natural gas system comprising: a pressurized natural gas source; a gas distributer comprising: a natural gas plenum, an inlet port leading into the natural gas plenum, and a plurality of outlet ports each leading out of the natural gas plenum, each of the outlet ports including a first connector that is configured to be coupled in a gastight connection to a second connector that is on a gas supply line.

2. The compressed natural gas system as recited in claim 1, wherein the pressurized gas source is a pressure reduction system.

3. The compressed natural gas system as recited in claim 1 , wherein the natural gas plenum includes a pipe that has a first diameter and each of the outlet ports has a second diameter that is smaller than the first diameter.

4. The compressed natural gas system as recited in claim 1 , further comprising at least one support stand having support legs, the support stand holding the natural gas plenum at an elevated height off of a surface on which the support legs are set.

5. The compressed natural gas system as recited in claim 4, wherein the support legs have a cradle portion into which the natural gas plenum nests for support.

6. The compressed natural gas system as recited in claim 5, wherein the natural gas plenum includes a plurality of pipe sections attached end-to-end.

7. The compressed natural gas system as recited in claim 6, wherein each of the outlet ports extends perpendicularly to the pipe sections.

8. The compressed natural gas system as recited in claim 6, wherein each of the pipe sections has multiple ones of the outlet ports.

9. The compressed natural gas system as recited in claim 6, wherein relative to the surface on which the support legs are set, both the support stand and the outlet ports are disposed on a surface-side half of the pipe sections.

10. A method comprising: fluidly connecting a gas feed line to an outlet of a pressure reduction system and to an inlet port leading into a natural gas plenum of a gas distributer; and fluidly connecting a plurality of gas supply lines to a plurality of outlet ports each leading out of the natural gas plenum, each of the outlet ports including a first connector and each of the gas supply lines including a second connector, wherein the fluidly connecting includes coupling the second connector in a gas-tight connection to one of the first connectors.

11. The method as recited in claim 10, further comprising feeding reduced-pressure compressed natural gas from the outlet of the pressure reduction system, through the gas feed line, to the natural gas plenum.

12. The method as recited in claim 11, further comprising feeding the reduced-pressure natural gas from the natural gas plenum, through the outlet ports, through the gas supply lines, to multiple pieces of equipment that are fluidly connected with the gas supply lines.

13. A method comprising : in a pressure reduction system, reducing a pressure of an input compressed natural gas from a first pressure to a second pressure to produce treated compressed natural gas at an outlet of the pressure reduction system; feeding the treated compressed natural gas from the outlet and through an inlet port into a natural gas plenum of a gas distributer; distributing the treated compressed natural gas through a plurality of gas supply lines connected to outlet ports of the natural gas plenum and delivering the treated compressed natural gas from the gas supply lines fluidly into to multiple pieces of equipment that are fluidly connected with the gas supply lines.

14. The method as recited in claim 14, further comprising feeding reduced-pressure natural gas from the outlet of the pressure reduction system, through the gas feed line, to the natural gas plenum.

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