WO2015051246A1

WO2015051246A1 - Integrated vent gas separator and flare stack

Info

Publication number: WO2015051246A1
Application number: PCT/US2014/059037
Authority: WO
Inventors: Timothy Long; Matthew B. GREEN; John MATHENA
Original assignee: Mathena, Inc.
Priority date: 2013-10-04
Filing date: 2014-10-03
Publication date: 2015-04-09
Also published as: US20150099231A1

Abstract

According to one aspect, an apparatus includes a separator vessel adapted to separate solid and liquid materials from gas materials; a flame arrestor in fluid communication with the separator vessel and through which the gas materials are adapted to flow; and a flare stack adapted to burn off the gas materials. The flare stack includes a vent pipe and an igniter. In another aspect, a system at a wellsite includes one or more separators adapted to be in fluid communication with a wellbore; one or more vent gas lines in fluid communication with the one or more separators; and an integrated vent gas separator and flare stack. In an exemplary embodiment, the one or more separators comprise at least one of a mud-gas separator and a shale-gas separator. In yet another aspect, a kit has first and second configurations. In still yet another aspect, a method is provided.

Description

INTEGRATED VENT GAS SEPARATOR AND FLARE STACK

Cross-Reference to Related Application

[0001] This application claims the benefit of the filing date of, and priority to, U.S. patent application number 61/887,141, filed October 4, 2013, the entire disclosure of which is hereby incorporated herein by reference.

Technical Field

[0002] This disclosure relates in general to vent gas separators and flare stacks and, in particular, an integrated vent gas separator and flare stack.

Background of the Disclosure

[0003] During the drilling of an oil or gas well, different materials may be discharged from the well. The discharged materials may include mixtures of solid, liquid and gas materials. These materials may be processed downstream of the well. As a result of one or more of these downstream processes, a multiphase flow including solid, liquid and gas materials may be generated. At least some of the materials in the multiphase flow may be separated from the remainder of the materials, and/or some of the materials may be burned. In some cases, some of the separated materials may not be properly contained, and/or possible fire hazards may be generated in connection with the separation and/or burning processes. Therefore, what is needed is an apparatus or method that addresses one or more of these issues, among others.

Summary

[0004] In a first aspect, there is provided an apparatus that includes a separator vessel adapted to separate solid and liquid materials from gas materials; a flame arrestor in fluid communication with the separator vessel and through which the gas materials are adapted to flow; and a flare stack adapted to burn off the gas materials. The flare stack is positioned so that the flame arrestor is vertically positioned between the separator vessel and the flare stack. The flare stack includes a vent pipe in fluid communication with the flame arrestor and positioned so that the flame arrestor is vertically positioned between the separator vessel and vent pipe; and an igniter in fluid communication with the vent pipe. The igniter is positioned so that the vent pipe is vertically positioned between the flame arrestor and the igniter.

[0005] In an exemplary embodiment, the apparatus includes a skid on which the separator vessel, the flame arrestor, and the flare stack are mounted. The flame arrestor is positioned so that the separator vessel is vertically positioned between the skid and the flame arrestor.

[0006] In another exemplary embodiment, the apparatus includes one or more guide wires extending from the skid to the flare stack to secure and stabilize the igniter. [0007] In yet another exemplary embodiment, the apparatus includes an outlet pipe generally centered on the top of the separator vessel and extending upward therefrom. The flame arrestor is in fluid communication with the outlet pipe and is positioned so that the outlet pipe is vertically positioned between the separator vessel and the flame arrestor. The separator vessel is generally centered on the skid.

[0008] In certain exemplary embodiments, the apparatus includes one or more guide wires to secure and stabilize the igniter, each of the one or more guide wires extending to the flare stack from the skid. The centering of the outlet pipe on the top of the separator vessel, and the centering of the separator vessel on the skid, facilitates the securement and stabilization of the igniter by the one or more guide wires.

[0009] In an exemplary embodiment, the separator vessel defines an internal region and includes an access port and a cap flange removably connected thereto. The access port provides access to the internal region. When the solid and liquid materials are separated from the gas materials, the cap flange is connected to the access port and the separator vessel is a closed vessel that is closed to the atmosphere.

[0010] In another exemplary embodiment, the separator defines an internal region in which the solid and liquid materials are adapted to be separated from the gas materials. The apparatus further includes an inlet pipe via which the solid, liquid, and gas materials are adapted to flow into the internal region. The inlet pipe includes a first connection that extends angularly towards the separator vessel and is connected thereto. The angular extension of the first connection defines an angle from a horizontal plane. The angle from the horizontal plane ranges from greater than 0 degrees to less than 90 degrees.

[0011] In yet another exemplary embodiment, at least respective portions of the solid, liquid, and gas materials are adapted to flow into the internal region, via the first connection, in a generally angular direction that corresponds to the first angle. The first angle ranges from about 10 degrees to about 80 degrees.

[0012] In certain exemplary embodiments, the separator defines an internal region in which the solid and liquid materials are adapted to be separated from the gas materials. The apparatus further includes an inlet pipe via which the solid, liquid, and gas materials are adapted to flow into the internal region. The inlet pipe includes a horizontally-extending portion that extends axially along the separator vessel, the horizontally-extending portion including first and second connections located at opposing ends, respectively, of the horizontally-extending portion. The first and second connections are connected to the separator vessel. The solid, liquid, and gas materials are adapted to flow into the internal region via the first and second connections.

[0013] In an exemplary embodiment, each of the first and second connections extends angularly towards the separator vessel. Each of the angular extensions of the first and second connections defines an angle from a horizontal plane. The angle from the horizontal plane ranges from greater than 0 degrees to less than 90 degrees.

[0014] In a second aspect, there is provided a system at a wellsite. The system includes one or more separators adapted to be in fluid communication with a wellbore at the wellsite; one or more vent gas lines in fluid communication with the one or more separators; and an integrated vent gas separator and flare stack, including a skid; a vessel mounted on the skid, in fluid communication with the one or more vent gas lines, and adapted to separate solid and liquid materials from gas materials; a flame arrestor in fluid communication with the vessel and positioned so that the vessel is vertically positioned between the skid and the flame arrestor; and a flare stack in fluid communication with the flame arrestor and adapted to burn off the gas materials. The flare stack is positioned so that the flame arrestor is vertically positioned between the vessel and the flare stack.

[0015] In an exemplary embodiment, the flare stack includes a vent pipe and an igniter connected thereto.

[0016] In another exemplary embodiment, the system includes one or more guide wires extending from the skid to the flare stack. The one or more guide wires secure and stabilize the igniter.

[0017] In yet another exemplary embodiment, the vessel defines an internal region and includes an access port and a cap flange removably connected thereto. The access port provides access to the internal region. When the solid and liquid materials are separated from the gas materials, the cap flange is connected to the access port and the vessel is a closed vessel that is closed to the atmosphere.

[0018] In certain exemplary embodiments, the one or more separators include at least one of a mud- gas separator and a shale-gas separator.

[0019] In a third aspect, there is provided a kit which, when assembled, is adapted to process a multiphase flow at a wellsite, the multiphase flow including solid, liquid, and gas materials. The kit includes a skid; a vessel mounted on the skid and into which the multiphase flow is adapted to flow to separate the solid and liquid materials from the gas materials, wherein the mounting of the vessel on the skid defines opposing first and second side portions of the skid, and wherein the vessel is positioned between the opposing first and second side portions of the skid; an inlet pipe connected to the vessel and via which the multiphase is adapted to flow into the vessel, wherein at least a portion of the inlet pipe extends above the first side portion; a flame arrestor; a vent pipe; and an igniter. The kit has a first configuration in which: each of the flame arrestor, the vent pipe, and the igniter either is mounted on the second side portion of the skid or extends over the second side portion of the skid; and each of the vent pipe and the igniter extends horizontally. The kit has a second configuration in which: the flame arrestor extends vertically and is positioned so that the vessel is vertically positioned between the skid and the flame arrestor; the gas materials are adapted to flow through the flame arrestor; the vent pipe extends vertically and is positioned so that the flame arrestor is vertically positioned between the vessel and the vent pipe; the gas materials are adapted to flow through the vent pipe; the igniter extends vertically and is positioned so that the vent pipe is vertically positioned between the flame arrestor and the igniter; and the igniter is adapted to burn off the gas materials.

[0020] In an exemplary embodiment, when the kit is in the first configuration: one of the vent pipe and the igniter is mounted on the second side portion of the skid; the other of the vent pipe and the igniter extends above the second side portion of the skid; and the flame arrestor is mounted on the second side portion of the skid.

[0021] In another exemplary embodiment, the vessel defines an internal region and includes an access port and a cap flange removably connected thereto. The access port provides access to the internal region. When the solid and liquid materials are separated from the gas materials, the cap flange is connected to the access port and the vessel is a closed vessel that is closed to the atmosphere.

[0022] In a fourth aspect, there is provided a method that includes providing a skid and a separator vessel mounted on the skid, wherein the mounting of the separator vessel on the skid defines opposing first and second side portions of the skid, wherein the separator vessel is positioned between the opposing first and second side portions of the skid, and wherein each of a flame arrestor, a horizontally-extending vent pipe, and a horizontally-extending igniter either is mounted on the second side portion of the skid or extends over the second side portion of the skid; accessing the flame arrestor at the second side portion of the skid; connecting the flame arrestor to the separator vessel so that the flame arrestor extends vertically; accessing the horizontally-extending vent pipe at the second side portion of the skid; connecting the vent pipe to the flame arrestor so that the vent pipe extends vertically; accessing the horizontally-extending igniter at the second side portion of the skid; and connecting the igniter to the vent pipe so that the igniter extends vertically.

[0023] In an exemplary embodiment, the method includes connecting one or more guide wires between the igniter and the skid to secure and stabilize the igniter.

[0024] In another exemplary embodiment, an inlet pipe is connected to the separator vessel and at least a portion of the inlet pipe extends over the first side portion of the skid. The method further includes connecting one or more fluid lines to the inlet pipe; conveying a multiphase flow into the separator vessel via the one or more fluid lines and the inlet pipe, the multiphase flow including solid, liquid, and gas materials; separating, using the separator vessel, the solid and liquid materials from the gas materials; conveying the gas materials upwardly into the flame arrestor; and conveying the gas materials upwardly from the flame arrestor and into the igniter.

[0025] In yet another exemplary embodiment, the one or more fluid lines include at least one vent gas line that is in fluid communication with one of a mud-gas separator and a shale-gas separator. [0026] In certain exemplary embodiments, the separator vessel defines an internal region and includes an access port and a cap flange removably connected thereto. The access port provides access to the internal region.

[0027] Other aspects, features, and advantages will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which are a part of this disclosure and which illustrate, by way of example, principles of the inventions disclosed.

Description of Figures

[0028] The accompanying drawings facilitate an understanding of the various embodiments.

[0029] Figure 1 is a perspective view of an apparatus according to an exemplary embodiment.

[0030] Figure 2 is a front elevational view of the apparatus of Figure 1, according to an exemplary embodiment.

[0031] Figure 3 is a left side elevational view of the apparatus of Figures 1 and 2, according to an exemplary embodiment.

[0032] Figure 4 is a top plan view of the apparatus of Figures 1-3, according to an exemplary embodiment.

[0033] Figure 5 is a diagrammatic illustration of the apparatus of Figures 1 -4 installed at an oil and gas wellsite, according to an exemplary embodiment.

[0034] Figures 6 and 7 are flow chart illustrations of a method of processing multiphase flow at the oil and gas wellsite of Figure 5, according to an exemplary embodiment.

[0035] Figure 8 is a diagrammatic illustration of a system installed at an oil and gas wellsite according to an exemplary embodiment, the system including an apparatus.

[0036] Figure 9 is a perspective view of the apparatus of Figure 8, according to an exemplary embodiment.

[0037] Figures 10-12 are respective elevational views of the apparatus of Figure 9, according to an exemplary embodiment.

[0038] Figure 13 is a sectional view of a portion of the apparatus of Figures 9- 12 taken along line 13-

13 of Figure 9, according to an exemplary embodiment.

[0039] Figure 14 is a sectional view of a portion of the apparatus of Figures 9- 13 taken along line 14-

14 of Figure 13, according to an exemplary embodiment.

[0040] Figure 15 is a view similar to that of Figure 9, but also depicting guide wires according to an exemplary embodiment.

[0041] Figure 16 is a view similar to that of Figure 9, but depicting the apparatus in a different configuration according to an exemplary embodiment. [0042] Figures 17 and 18 are elevational views of the apparatus in the configuration of Figure 16, according to an exemplary embodiment.

[0043] Figure 19 is a flow chart illustration of a method of installing the apparatus of Figures 8-18, according to an exemplary embodiment.

Detailed Description

[0044] In an exemplary embodiment, as illustrated in Figures 1 -4, an apparatus is generally referred to by the reference numeral 10 and includes a skid 12 on which a secondary containment vessel 14 is mounted. A separator vessel 16 is connected to the secondary containment vessel 14. A flame arrestor 18 is connected to the separator vessel 16. A flare stack 20 is connected to the flame arrestor 18, and includes an integrated igniter 22 at the upper end portion thereof. A frame 24 is mounted on the skid 12, and is connected to the secondary containment vessel 14. The frame 24 includes a horizontally-extending working platform 26. Guide wires 28a, 28b, 28c, and 28d extend to the upper end portion of the flare stack 20 from respective ones of four corners defined by the skid 12. In an exemplary embodiment, one or more of the guide wires 28a, 28b, 28c and 28d are connected to the upper end portion of the flare stack 20. In an exemplary embodiment, one or both of the guide wires 28a and 28b are connected to the igniter 22, and the guide wires 28c and 28d are connected to the upper end portion of the flare stack 20. In an exemplary embodiment, the guide wires 28a, 28b, 28c and 28d are all connected to the upper end portion of the flare stack 20.

[0045] The frame 24 includes vertical supports 30a, 30b, 30c and 30d extending upward from the skid 12. The working platform 26 is connected to the respective upper ends of the vertical supports 30a, 30b, 30c and 30d.

[0046] The secondary containment vessel 14 is in the form of a box-like structure and includes a vertically- extending side portion 32a extending between the vertical supports 30a and 30b, a vertically- extending side portion 32b extending between the vertical supports 30b and 30c, a vertically- extending side portion 32c extending between the vertical supports 30c and 30d, and a vertically-extending side portion 32d extending between the vertical supports 30d and 30a. A horizontally-extending top portion 34 is connected to the respective upper ends of the side portions 32a, 32b, 32c and 32d. The top portion 34 of the secondary containment vessel 14 is positioned beneath, and is spaced in a parallel relation from, the working platform 26.

[0047] The secondary containment vessel 14 defines an interior, which is defined by at least the top portion 34 and the side portions 32a, 32b, 32c and 32d, as well as by either the skid 12 or a bottom portion connected to or otherwise mounted on the skid 12; in an exemplary embodiment, the secondary containment vessel 14 includes one or more internal liners disposed within the internal region. In an exemplary embodiment, the secondary containment vessel 14 is a stand-alone tank connected to the skid 12 and/or one or more of the vertical supports 30a, 30b, 30c and 30d. In several exemplary embodiments, instead of, or in addition to being in the form of a box-like structure, the secondary containment vessel 14 is in the form of a cylindrical structure, a barrel-like structure, a duct-like structure, a closed-pan structure, a closed-tray structure, or any combination thereof.

[0048] In an exemplary embodiment, the frame 24 is part of the secondary containment vessel 14. In an exemplary embodiment, the frame 24 and the secondary containment vessel 14 are separate structures, each of which is connected to the other and/or to the skid 12. In an exemplary embodiment, the secondary containment vessel 14 is a structure separate from the frame 24, and includes the top portion 34 and the side portions 32a, 32b, 32c and 32d.

[0049] A drain port 36 is formed through the side portion 32a at the lower end portion thereof. A plug or cap 38 is removably connected to the drain port 36. A liquid-level switch 40 is connected to the side portion 32a at the upper end portion thereof. The liquid-level switch 40 is adapted to sense the fluid level within the secondary containment vessel 14, under conditions to be described below. In an exemplary embodiment, the liquid-level switch 40 is a Rosemount® 2100 Series Vibrating Fork Liquid Level Switch, which is available from Emerson Process Management Rosemount Inc., Chanhassen, Minnesota.

[0050] The side portion 32a includes an access port 42 and a cap flange 44 removably connected thereto. In an exemplary embodiment, the access port 42 and/or the cap flange 44 may be characterized as a manway or a cleanout, which provides access to the secondary containment vessel 14. Likewise, the side portion 32c includes an access port 46 and a cap flange 48 removably connected thereto. In an exemplary embodiment, the access port 46 and/or the cap flange 48 may be characterized as a manway or a cleanout, which provides access to the interior of the secondary containment vessel 14. In an exemplary embodiment, as shown Figures 1-4, the access port 46 opposes the access port 42.

[0051] The separator vessel 16 includes a cylindrical body 50 connected to the top portion 34 of the secondary containment vessel 14 via a flange 52, which is fastened to the top portion 34. The secondary containment vessel 14 is vertically positioned between the skid 12 and the separator vessel 16. An internal region 54 is at least partially defined by the cylindrical body 50. Although not shown in the figures, an opening is formed through the top portion 34 so that the internal region 54 of the separator vessel 16 is in fluid communication with the interior of the secondary containment vessel 14; the flange 52 extends circumferentially around the opening formed through the top portion 34. Due at least in part to the top portion 34 and the connection of the separator vessel 16 thereto via the flange 52, the secondary containment vessel 14 is a closed- top tank. No part of the secondary containment vessel 14 is directly open to the atmosphere, that is, the secondary containment vessel 14 is closed to the atmosphere, when the separator vessel 16 is connected to the secondary containment vessel 14, the drain port 36 is plugged with the cap 38, and the access ports 42 and 46 are closed by the cap flanges 44 and 48, respectively. [0052] An inlet 56 is connected to the cylindrical body 50, and defines an inlet fluid passage 56a in fluid communication with the internal region 54. In an exemplary embodiment, and as shown in Figures 1-4, the inlet 56 is a tangential inlet. The separator vessel 16 further includes a flange 58 connected to the cylindrical body 50 opposite the flange 52. A cap 60 is connected to the upper portion of the cylindrical body 50 via a flange 62, which is connected to the flange 58. In an exemplary embodiment, the internal region 54 is partially defined by the cap 60.

[0053] In an exemplary embodiment, the separator vessel 16 is a cyclonic separator. In an exemplary embodiment, the separator vessel 16 is a vortex separator. In an exemplary embodiment, the separator vessel 16 includes a vortex finder extending within the internal region 54; in an exemplary embodiment, the vortex finder includes a vertically-extending tubular member. In an exemplary embodiment, the separator vessel 16 includes one or more wear plates (not shown) disposed in the internal region 54 and proximate the inlet fluid passage 56a; the one or more wear plates are adapted to protect internal surfaces defined by the separator vessel 16 from fluid flow into the separator vessel 16 via the inlet 56. In an exemplary embodiment, the separator vessel 16 includes one or more baffles (not shown) disposed within the internal region 54 and vertically below the inlet 56; the one or more baffles are adapted to remove entrained gas from multiphase flow. In an exemplary embodiment, the separator vessel 16 includes one or more condenser baffles (not shown) disposed within the internal region 54 and proximate the flange 58 and/or the cap 60; the one or more condenser baffles are adapted to prevent any upward liquid flow out of the separator vessel 16.

[0054] In several exemplary embodiments, the separator vessel 16 and the secondary containment vessel 14 may be formed as a single vessel. In several exemplary embodiments, a single vessel may be substituted for the combination of the separator vessel 16 and the secondary containment vessel 14.

[0055] The flame arrestor 18 is connected to the top of the cap 60 of the separator vessel 16. The separator vessel 16 is vertically positioned between the secondary containment vessel 14 and the flame arrestor 18. The flame arrestor 18 is in fluid communication with the separator vessel 16. In an exemplary embodiment, the flame arrestor 18 is an Enardo® Series 8 High Pressure Deflagration Flame Arrestor, which is available from Enardo, LLC, Tulsa, Oklahoma.

[0056] The flare stack 20 is connected to the flame arrestor 18 opposite the cap 60, and extends upward from the flame arrestor 18. The flame arrestor 18 is vertically positioned between the flame arrestor 18 and the flare stack 20. The flare stack 20 is in fluid communication with the flame arrestor 18. The working platform 26 of the frame 24 is generally coplanar with the connection between flare stack 20 and the flame arrestor 18. In an exemplary embodiment, an opening is formed through the working platform 26, and one or both of the flame arrestor 18 and the flare stack 20 extend within the opening. In an exemplary embodiment, the frame 24 includes integrated handrails and a ladder; in several exemplary embodiments, the integrated handrails may be connected to the working platform 26 to provide safety for personnel standing on the working platform 26, and the ladder may provide safe access to the working platform 26.

[0057] In an exemplary embodiment, as illustrated in Figure 5 with continuing reference to Figures 1 - 4, the apparatus 10 is installed at an oil and gas wellsite 64, the wellsite 64 including a wellbore 66 that extends within a subterranean formation (not shown) and may be used in oil and gas exploration and production operations. To install the apparatus 10, the skid 12 is placed on a horizontal surface, such as the ground, at the wellsite 64. In an exemplary embodiment, the apparatus 10 may be transported to, and installed at, the wellsite 64 in the assembled condition shown in Figures 1-4. One or more fluid lines 68 such as, for example, one or more pipes or piping systems, are connected to the inlet 56 so that the apparatus 10 is in fluid communication with the wellbore 66 at the wellsite 64. In several exemplary embodiments, the apparatus 10 is in fluid communication with the wellbore 66 via at least one or more separators 70, that is, the apparatus 10 is in fluid communication with the one or more separators 70, which, in turn, are in fluid communication with the wellbore 66. In several exemplary embodiments, the one or more separators 70 include one or more mud-gas separators, one or more shale-gas separators, or any combination thereof. In an exemplary embodiment, the one or more fluid lines 68 are gas vent lines, and thus the apparatus 10 is in fluid communication with the one or more separators 70 via the one or more gas vent lines.

[0058] In operation, in an exemplary embodiment, with continuing reference to Figures 1-5, a multiphase flow travels from the one or more separators 70, through the one or more fluid lines 68, and into the internal region 54 of the separator vessel 16 via the inlet fluid passage 56a of the inlet 56. The multiphase flow traveling through the one or more fluid lines 68 includes solid, liquid and gas materials. The separator vessel 16 operates to separate the solid and liquid materials from the gas materials in the multiphase flow, conveying the gas materials upwards through the flame arrestor 18 and into the flare stack 20. The remaining solid and liquid materials (which have been separated from the gas materials) fall out of the separator vessel 16 and into the secondary containment vessel 14.

[0059] In several exemplary embodiments, during operation, the inlet 56 of the separator vessel 16 is a tangential inlet (as shown in Figures 1-4) and the multiphase flow exits the inlet fluid passage 56a and flows spirally within the internal region 54. During this spiral flow, at least respective portions of the solid and liquid materials of the multiphase flow are slung against the inside surface of the cylindrical wall 50 and flow axially downwards towards the secondary containment vessel 14. In contrast, the gas materials in the multiphase flow, which are relatively lighter in weight, are not so slung and instead are generally disposed closer to the radial center of the internal region 54. As a result, the solid and liquid materials are separated from the gas materials, and the gas materials flow axially upwards towards the flame arrestor 18. In several exemplary embodiments, the separator vessel 16 operates as a vortex or cyclonic separator.

[0060] In several exemplary embodiments, to separate the solid and liquid materials from the gas materials in the multiphase flow, the separator vessel 16 is sized and/or configured so that the lighter gas materials are permitted to rise or flow upwards towards the flame arrestor 18, and so that the heavier solid and liquid materials fall or flow downwards towards the secondary containment vessel 14. In several exemplary embodiments, the separator vessel 16 and the secondary containment vessel 14 are combined into a single vessel in which the separation and containment functions occur. In several exemplary embodiments, a single vessel is substituted for the combination of the separator vessel 16 and the secondary containment vessel 14, and the separation and containment functions occur in the single vessel.

[0061] The gas materials separated by the separator vessel 16 rise or flow upwards through the flame arrestor 18 and subsequently into the flare stack 20. The flare stack 20, which includes the igniter 22, operates to burn off the gas materials flowing into the flare stack 20.

[0062] The flame arrestor 18 allows the gas materials to flow therethrough, but arrests or stops a flame from propagating therethrough in order to prevent a larger fire or explosion. In several exemplary embodiments, the flame arrestor 18 stops any flame from the flare stack 20 from propagating through the flame arrestor 18 and into the separator vessel 16. The flame arrestor 18 prevents post-separation flame flashback. In several exemplary embodiments, the flame arrestor 18 includes one or more thermocouples, which may be in communication with a controller to monitor the temperature of the flame arrestor 18 during the operation of the apparatus 10; in some exemplary embodiments, the controller may activate an alarm and/or take other action(s) in response to the temperature monitoring.

[0063] In several exemplary embodiments, the flare stack 20 and the igniter 22 integrated therewith provide increased safety due to an increased elevation of flare, and the flame arrestor 18 provides integrated flare flashback prevention.

[0064] In contrast to the gas materials, the solid and liquid materials fall or flow downwards into the secondary containment vessel 14 for collection therein. The solid and liquid materials continue to collect in the secondary containment vessel 14 until they reach a predetermined level, at which point the liquid- level switch 40 detects that the secondary containment vessel 14 is full. In an exemplary embodiment, when the secondary containment vessel 14 is full, the secondary containment vessel 14 is drained by removing the cap 38 from the drain port 36, thereby allowing at least the liquid materials to flow out of the secondary containment vessel 14.

[0065] During the operation of the apparatus 10, in an exemplary embodiment, the liquid-level switch 40 may continuously or nearly continuously monitor the liquid level within the secondary containment vessel 14. In an exemplary embodiment, the liquid-level switch 40 may be in communication with a controller to monitor the liquid level, and/or detect when the liquid level reaches the predetermined level, within the secondary containment tank 40; in some exemplary embodiments, the controller may activate an alarm and/or take other action(s) in response to the liquid-level monitoring. Such other actions may include automatically draining the secondary containment vessel 14 by automatically opening the drain port 36.

[0066] During the operation of the apparatus 10, in several exemplary embodiments, the guide wires 28a, 28b, 28c and 28d secure and stabilize the igniter 22. In several exemplary embodiments, the guide wires 28a, 28b, 28c and 28d secure and stabilize the igniter 22 during the transportation of the apparatus 10, and/or during the installation of the apparatus 10 at the wellsite 64.

[0067] As noted above, due at least in part to the top portion 34 and the connection of the separator vessel 16 thereto via the flange 52, the secondary containment vessel 14 is a closed- top tank. In several exemplary embodiments, the respective interconnections between the vessel 14 and the separator vessel 16, between the separator vessel 16 and the flame arrestor 18, and between the flame arrestor 18 and the flare stack 20, ensure that separation is achieved in a closed system, with post-separation dynamics ensuring that only vent gas is discharged to the flare stack 20.

[0068] In several exemplary embodiments, the one or more fluid lines 68 is a vent gas line, and the apparatus 10 functions both as a vent gas separator (or vent gas scrubber) and a secondary containment flare system. The apparatus 10 effectively separates and contains solid and liquid carryover in the vent gas flowing through the fluid lines 68 and into the apparatus 10, while burning off the gas materials. In several exemplary embodiments, since the secondary containment vessel 14 is integrated with the separator vessel 16, the apparatus 10 ensures the collection and storage of solid and liquid materials entrained in the vent gas.

[0069] As noted above, due at least in part to the top portion 34 and the connection of the separator vessel 16 thereto via the flange 52, the secondary containment vessel 14 is a closed-top tank. The secondary containment vessel 14 being a closed-top tank, as well as the interconnection between the secondary containment vessel 14 and the separator vessel 16, the interconnection between the separator vessel 16 and the flame arrestor 18, and the interconnection between the flame arrestor 18 and the flare stack 20, provide a closed system in which only the flare stack 20 is open to the atmosphere during the operation of the apparatus 10, that is, during the separation of the solid and liquid materials from the gas materials and the burning off of the gas materials, when the drain port 36 is plugged with the cap 38 and the access ports 42 and 46 are closed by the cap flanges 44 and 48, respectively.

[0070] In several exemplary embodiments, the apparatus 10 is an integrated separator and secondary containment flare apparatus. In several exemplary embodiments, the apparatus 10 is an integrated vent gas separator (or vent gas scrubber) and secondary containment flare apparatus. [0071] In several exemplary embodiments, the above-described integration and vertical stack-up of the different components of the apparatus 10 reduces the footprint of the apparatus 10 and provides a compact structure. Further, the above-described integration and vertical stack-up of the different components of the apparatus 10 facilitates the transportation and installation of the apparatus 10. Still further, the above- described integration and vertical stack-up of the different components of the apparatus 10 facilitates the above-described operation of the apparatus 10 in that, for example, the heavier solid and liquid materials fall from the separator vessel 16 and into the secondary containment vessel 14, and the lighter gas materials rise up from the separator vessel 16, through the flame arrestor 18, and into the flare stack 20.

[0072] In several exemplary embodiments, the respective sizes of the apparatus 10 and its components may be scaled accordingly. In an exemplary embodiment, the length and width of the skid 12 may be about 192 inches and 72 inches, respectively, the height of the flare stack 20 from the horizontal surface on which the skid 12 rests may be about 225 inches, and the height of the working platform 26 from the horizontal surface on which the skid 12 rests may be about 104 inches.

[0073] In an exemplary embodiment, as illustrated in Figures 6 and 7 with continuing reference to Figures 1-5, a method of processing multiphase flow at the wellsite 64 is generally referred to by the reference numeral 72. The method 72 includes at step 72a mounting the secondary containment vessel 14 on the skid 12, at step 72b connecting the separator vessel 16 to the secondary containment vessel 14, and at step 72c connecting the flame arrestor 18 to the separator vessel 16. At step 72d, the skid 12, and thus also the secondary containment vessel 14, the separator vessel 16, and the flame arrestor 18, are transported to the wellsite 64. At step 72e, the skid 12, and thus also the secondary containment vessel 14, the separator vessel 16, and the flame arrestor 18, are installed at the wellsite 64. At step 72f, the one or more vent gas lines 68 are connected between the separator vessel 16 and the one or more separators 70. At step 72g, the multiphase flow is conveyed from the one or more separators 70 and into the one or more vent gas lines 68. At step 72h, the multiphase flow is conveyed from the one or more vent gas lines 68 and into the separator vessel 16. At step 72i, using the separator vessel 16, solid and liquid materials in the multiphase flow are separated from gas materials in the multiphase flow. At step 72j, the solid and liquid materials are conveyed downwardly into the secondary containment vessel 14. At step 72k, the gas materials are conveyed upwardly into the flame arrestor 18. In an exemplary embodiment, the method 72 further includes connecting the flare stack 20 to the flame arrestor 18, and conveying the gas materials upwardly from the flame arrestor 18 and into the flare stack 20. In an exemplary embodiment, the method 72 further includes connecting one or more guide wires between the skid 12 and the upper end portion of the flare stack 20 to secure and stabilize the igniter 22.

[0074] In several exemplary embodiments, the majority of the flare stack 20 may not be positioned on the skid 12; instead, at least a portion (such a fluid line or piping) of the flare stack 20 may be connected to, and positioned above, the flame arrestor 18, and at least the majority of the remaining portion of the flare stack 20 may be positioned next to, or at a distance away from, the skid 20.

[0075] In an exemplary embodiment, as illustrated in Figure 8, a system is generally referred to by the reference numeral 74 and includes an apparatus 76, which is installed at an oil and gas wellsite 78. The wellsite 78 includes a wellbore 80 that extends within a subterranean formation (not shown) and may be used in oil and gas exploration and production operations. The system 74 further includes one or more separators 82, which are in fluid communication with the wellbore 80. The apparatus 76 includes a fluid inlet 84, which is in fluid communication with the one or more separators 82 via one or more fluid lines 86. The apparatus 76 is in fluid communication with the wellbore 80 via the one or more fluid lines 86 and the one or more separators 82. In several exemplary embodiments, the one or more separators 82 include one or more mud-gas separators, one or more shale-gas separators, or any combination thereof. In an exemplary embodiment, the one or more fluid lines 86 are gas vent lines, and thus the apparatus 76 is in fluid communication with the one or more separators 82 via the one or more gas vent lines.

[0076] In an exemplary embodiment, as illustrated in Figures 9-12 with continuing reference to Figure 8, the apparatus 76 includes a skid 88 on which a separator vessel 90 is mounted via vessel mounting brackets 92a, 92b, and 92c, which are connected to the skid 88. The vessel 90 includes opposing axial end portions 90a and 90b. An access port 90c (shown most clearly in Figure 13) is formed in the vessel 90 at the axial end portion 90b. A cap flange 90d is removably connected to the access port 90c. In an exemplary embodiment, the access port 90c and/or the cap flange 90d may be characterized as a manway or a cleanout, which provides access to the interior of the vessel 90.

[0077] The skid 88 defines a length 88a and a width 88b perpendicular thereto. The mounting brackets 92a, 92b, and 92c are horizontally spaced from each other along a length direction of the skid 88. The vessel 90 is generally cylindrical in shape, and extends horizontally along a length direction of the skid 88. The vessel 90 is generally centered on the skid 88, with the center of the vessel 90 being generally positioned about midway along the length 88a of the skid 88, and about midway along the width 88b of the skid 88. Opposing side portions 88c and 88d of the skid 88 are defined by the position of the vessel 90 on the skid 88. The side portions 88c and 88d extend along the length 88a of the skid 88. The vessel 90 is positioned between the opposing side portions 88c and 88d. Igniter mounting brackets 94a and 94b are connected to the skid 88 on the side portion 88c thereof, and are horizontally spaced along a length direction of the skid 88. Similarly, flame arrestor mounting brackets 96a and 96b are connected to the skid 88 on the side portion 88c thereof, and are horizontally spaced along a length direction of the skid 88.

[0078] An outlet pipe 98 is connected to, and generally centered on, the top of the vessel 90, and extends vertically upward therefrom. Gussets 100 extend between the vessel 90 and the outlet pipe 98, supporting the outlet pipe 98. A concentric reducer 102 is connected to the outlet pipe 98 and extends vertically upward therefrom. A flame arrestor 104 is connected to the concentric reducer 102 and extends vertically upward therefrom so that the concentric reducer 102 is vertically positioned between the outlet pipe 98 and the flame arrestor 104. The flame arrestor 104 is in fluid communication with the outlet pipe 98 and is positioned so that the outlet pipe 98 is vertically positioned between the vessel 90 and the flame arrestor 104, and so that the vessel 90 is vertically positioned between the skid 88 and the flame arrestor 104. In an exemplary embodiment, the flame arrestor 104 is an Enardo® Series 8 High Pressure Deflagration Flame Arrestor, which is available from Enardo, LLC, Tulsa, Oklahoma. A vent pipe 106 is connected to, and in fluid communication with, the flame arrestor 104 and extends vertically upward therefrom so that the flame arrestor 104 is vertically positioned between the concentric reducer 102 and the vent pipe 106. An igniter 108 is connected to, and in fluid communication with, the vent pipe 106 and extends vertically upward therefrom so that the vent pipe 106 is vertically positioned between the flame arrestor 104 and the igniter 108. In several exemplary embodiments, the combination of at least the vent pipe 106 and the igniter 108 connected thereto constitutes a flare stack having an integrated igniter at the upper end portion thereof. In several exemplary embodiments, the vent pipe 106 is omitted and a lower end tubular portion of the igniter 108 is a vent pipe connected to, and in fluid communication with, the flame arrestor 104, and is vertically positioned between the flame arrestor 104 and the igniter 108; in several exemplary embodiments, such an igniter 108 with its lower end tubular portion being a vent pipe constitutes a flare stack having an integrated igniter at the upper end portion thereof. In an exemplary embodiment, the vent pipe 106 and the igniter 108 may be combined and form an integral component, with the lower end tubular portion thereof being the vent pipe and the upper end portion being the igniter; in several exemplary embodiments, such a combination constitutes a flare stack having an integrated igniter at the upper end portion thereof.

[0079] A drain pipe 1 10 is connected to the vessel 90 and positioned vertically between the skid 88 and the vessel 90, extends axially along the underside of the vessel 90. In several exemplary embodiments, the drain pipe 1 10 extends through, and/or is supported by, the vessel mounting brackets 92a, 92b, and 92c. A fluid outlet 1 10a is defined by the drain pipe 1 10 at a location proximate the axial end portion 90a of the vessel 90. The drain pipe 1 10 includes a valve 1 10b adapted to control fluid flow out of the drain pipe 1 10 via the fluid outlet 1 10a. An igniter control box 1 12 is connected to the vessel 90 at the axial end portion 90a thereof, and is adapted to control the operation of the igniter 108. Vent pipe mounting brackets 1 14a and 1 14b are connected to the vessel 90. The vent pipe mounting brackets 1 14a and 1 14b extend from the side of the vessel 90 so that the vent pipe mounting brackets 1 14a and 1 14b are positioned above the side portion 88c of the skid 88. A sensor pipe 1 16 extends from the side of the vessel 90 at a lower portion thereof. The sensor pipe 1 16 extends from the side of the vessel 90 so that the sensor pipe 1 16 is positioned over the side portion 88c of the skid 88.

[0080] A liquid- level switch 1 18 is connected to the sensor pipe 1 16. At least a portion of the liquid- level switch 1 18 is housed within the sensor pipe 1 16. The liquid-level switch 1 18 is adapted to sense the liquid level within the vessel 90, under conditions to be described below. In an exemplary embodiment, the liquid-level switch 1 18 is a horizontal level control switch with an annulus plug. In an exemplary embodiment, the liquid-level switch 118 is a Wellmark® Model 790 Horizontal Floatswitch, which is available from The Wellmark Company, L.L.C., Oklahoma City, Oklahoma.

[0081] An inlet pipe 120 is located above the side portion 88d of the skid 88, and includes a horizontally-extending portion 120a. The fluid inlet 84 is defined by the horizontally-extending portion 120a. As indicated above, the fluid inlet 84 is in fluid communication with the one or more fluid lines 86 shown in Figure 8. The horizontally-extending portion 120a is located and extends above the side portion 88d of the skid 88, and extends along a portion of the vessel 90. A vertically-extending portion 120b is connected to the horizontally- extending portion 120a via an elbow connection 120c. A transversely- extending portion 120d is connected to the vertically- extending portion 120b via an elbow connection 120e. The transversely-extending portion 120d extends horizontally over the top of the vessel 90 and along a width direction of the skid 88. A horizontally-extending portion 120f is connected to the transversely-extending portion 120d. The horizontally-extending portion 120f extends axially along the vessel 90, and is closer to the side portion 88c than to the side portion 88d. The horizontally-extending portion 120f includes an elbow connection 120g at one end thereof, and an opposing elbow connection 120h at the other end thereof. The elbow connections 120g and 120h are connected to the vessel 90. The elbow connection 120g is connected to the vessel 90 at the axial end portion 90a of the vessel 90. The elbow connection 120h is connected to the vessel 90 at the axial end portion 90b of the vessel 90. The transversely-extending portion 120d is connected to the horizontally-extending portion 120f at a location between the elbow connections 120g and 120h. In an exemplary embodiment, as shown in Figures 9-12, the horizontally- extending portion 120f includes a T-connection 120i, to which at least the transversely- extending portion 120d and the elbow connection 120g are connected. In another exemplary embodiment, the horizontally-extending portion 120f includes a cross connection (not shown), to which at least the transversely-extending portion 120d and the elbow connection 120g are connected.

[0082] As shown in Figures 9, 10, and 12, the elbow connections 120g and 120h extend angularly, from the horizontally- extending portion 120f and towards the vessel 90. As shown most clearly in Figure 10, this angular extension defines an angle 122, relative to a horizontal plane 123 defined by the skid 88 and on which the vessel mounting brackets 92a, 92b, and 92c are mounted. In an exemplary embodiment, the angle 122 ranges from greater than 0 degrees to less than 90 degrees. In an exemplary embodiment, the angle 122 ranges from about 10 degrees to about 80 degrees. In an exemplary embodiment, the angle 122 ranges from about 15 degrees to about 75 degrees. In an exemplary embodiment, the angle 122 ranges from about 20, 30, 40, or 50 degrees, and to about 70 degrees. In an exemplary embodiment, the angle 122 is about 60 degrees. In an exemplary embodiment, the angle 122 is about 45 degrees.

[0083] In an exemplary embodiment, the horizontally-extending portion 120f may be located closer to the side portion 88d than to the side portion 88c, the elbow connections 120h and 120i may extend angularly towards the vessel 90, and the angle 122 may be a symmetric equivalent, about the generally centered vent pipe 106, of the exemplary embodiment of the angle 122 shown in Figure 10.

[0084] A working platform 124 is connected to the vessel 90 and positioned above the side portion 88d of the skid 88. The working platform 124 is proximate the outlet pipe 98 so that any personnel installing, disassembling, inspecting, or operating the apparatus 76, or conducting other activities related to the apparatus 76, can access at least the concentric reducer 102, the flame arrestor 104, and the vent pipe 106. A stairway assembly 126 extends from the side portion 88d of the skid 88, and to the working platform 124, thereby providing access to the working platform 124.

[0085] In several exemplary embodiments, the respective sizes of the apparatus 76 and its components may be scaled accordingly. In an exemplary embodiment, the length 88a and width 88b of the skid 12 may be about 189 inches and 92 inches, respectively. In an exemplary embodiment, the height of the upper end portion of the igniter 108, from the horizontal surface on which the skid 88 rests, may be about 336 inches.

[0086] In an exemplary embodiment, as illustrated in Figures 13 and 14 with continuing reference to Figures 8-12, the vessel 90 defines a cylindrical inside surface 90e, as well as an internal region 128 with which the inlet pipe 120 is in fluid communication. More particularly, the elbow connections 120g and 120h of the inlet pipe 120 are in fluid communication with the internal region 128. The outlet pipe 98 is in fluid communication with the internal region 128. The drain pipe 1 10 is in fluid communication with the internal region 128 at two locations. More particularly, the drain pipe 1 10 includes a vertically- extending duct 1 10c that is connected to the underside of the vessel 90 at the axial end portion 90a thereof. The vertically-extending duct 1 10c is in fluid communication with the internal region 128. Additionally, the drain pipe 1 10 includes an elbow connection 1 1 Od at the end of the drain pipe 110 opposite the inlet 1 10a. The elbow connection 1 lOd is connected to the underside of the vessel 90, and is in fluid communication with the internal region 128. A plate 130a is connected to the inside surface 90e, and extends across the intersection between the vertically- extending duct 1 10c and the vessel 90. Likewise, a plate 130b is connected to the inside surface 90e, and extends across the intersection between the elbow connection 1 lOd and the vessel 90. The plates 130a and 130b extend upwards from the inside surface 90e and within the internal region 128. Under conditions to be described below, the plates 130a and 130b are adapted to operate as vortex breakers.

[0087] As shown in Figure 13, the liquid-level switch 1 18 is exposed to the internal region 128 via the intersection between the sensor pipe 1 16 and the vessel 90. In an exemplary embodiment, the liquid- level switch 1 18 extends out from the sensor pipe 1 16 and into the internal region 128. A height H is defined between the nominal center of the liquid-level switch 1 18 and the tangential bottom of the inside surface 90e.

[0088] In an exemplary embodiment, as illustrated in Figure 15 with continuing reference to Figures 8-14, the apparatus 76 includes guide wires 132a, 132b, 132c, and 132d, which extend to the igniter 108 from respective ones of the four corners defined by the skid 88. In an exemplary embodiment, the guide wires 132a, 132b, 132c, and 132d are connected to the igniter 108 at the connection thereof with the vent pipe 106, as shown in Figure 15. In an exemplary embodiment, the guide wires 132a, 132b, 132c, and 132d are connected to the igniter 108 at a location other than at the connection between the igniter 108 and the vent pipe 106. In an exemplary embodiment, the apparatus 76 includes one or more other guide wires, in addition to the guide wires 132a, 132b, 132c, and 132d. In an exemplary embodiment, at least one of the guide wires 132a, 132b, 132c, and 132d is omitted from the apparatus 76; in such an exemplary embodiment, the remaining ones of the guide wires 132a, 132b, 132c, and 132d may be connected to the skid 88 at respective locations other than the corners of the skid 88. In an exemplary embodiment, one or more of the guide wires 132a, 132b, 132c, and 132d may be connected to the skid 88 at respective locations other than the corners of the skid 88.

[0089] In operation, in an exemplary embodiment, with continuing reference to Figures 8-15, a multiphase flow travels from the one or more separators 82, through the one or more fluid lines 86, and into the inlet pipe 120 of the apparatus 76 via the fluid inlet 84. In several exemplary embodiments, the multiphase flow is, or includes, vent gas from the one or more separators 82.

[0090] The multiphase flow travels through the horizontally-extending portion 120a, the elbow connection 120c, the vertically-extending portion 120b, the elbow connection 120e, and the transversely- extending portion 120d of the inlet pipe 120. Upon exiting the transversely-extending portion 120d, the multiphase flow splits into two different flow paths. More particularly, one portion of the multiphase flow travels through the elbow connection 120g and into the internal region 128, as indicated by an arrow 134 in Figure 13; the other portion of the multiphase flow travels through the elbow connection 120h and into the internal region 128, as indicated by an arrow 136 in Figures 13 and 14. Due to the angle 122, the respective portions of the multiphase flow into the internal region 128, as indicated by the arrows 134 and 136, in a generally angular direction that corresponds to the angle 122. The multiphase flow traveling through the one or more fluid lines 86 includes solid, liquid, and gas materials. Within the internal region 128, the solid and liquid materials separate from the gas materials in the multiphase flow; the gas materials rise or flow upwards through the outlet pipe 98, the concentric reducer 102, the flame arrestor 104, and the vent pipe 106, and into the igniter 108. This upward flow of the gas materials is indicated by an arrow 138 in Figures 13 and 14. In several exemplary embodiments, the remaining solid and liquid materials (which have been separated from the gas materials) collect within, and are contained by, the drain pipe 1 10 and the vessel 90; the valve 1 10b is closed so that the remaining solid and liquid materials may be contained within the drain pipe 1 10 and the vessel 90.

[0091] In several exemplary embodiments, during operation, the remaining solid and liquid materials (which have been separated from the gas materials) collect within the vessel 90 and then may be drained out via the drain pipe 1 10. More particularly, the remaining solid and liquid materials flow through the duct 1 10c and the elbow connection 1 lOd, then through the remainder of the drain pipe 1 10, exiting the drain pipe 1 10 via the fluid outlet 1 10a, as indicated by an arrow 140 in Figure 13. During operation, in several exemplary embodiments, the valve 1 10b is open or partially open to permit the remaining solid and liquid materials to exit the drain pipe 110 via the fluid outlet 1 10a. In several exemplary embodiments, the remaining solid and liquid materials flow through one or more additional fluid lines that are in fluid communication with the fluid outlet 1 10a, and to an external tank or fluid reservoir for collection and storage therewithin.

[0092] As noted above, the gas materials rise or flow upwards through the outlet pipe 98, the concentric reducer 102, the flame arrestor 104, and the vent pipe 106, and into the igniter 108. The igniter 108 operates to burn off the gas materials that flow therein. As noted above, in several exemplary embodiments, the combination of at least the vent pipe 106 and the igniter 108 connected thereto constitutes a flare stack having an integrated igniter at the upper end portion thereof; the flare stack operates to burn off the gas materials that flow therein. In several exemplary embodiments, the igniter 108 includes one or more thermocouples and/or other sensors, which may be in communication with the igniter control box 1 12 and/or other controller(s) to monitor temperatures and/or other operating condition(s) of the igniter 108 during the operation of the apparatus 76; in some exemplary embodiments, the igniter control box 1 12 may activate an alarm and/or take other action(s) in response to this monitoring.

[0093] The flame arrestor 104 allows the gas materials to flow therethrough, but arrests or stops a flame from propagating therethrough in order to prevent a larger fire or explosion. In several exemplary embodiments, the flame arrestor 104 stops any flame, within the vent pipe 106 or the igniter 108, from propagating through the flame arrestor 104 and into the vessel 90. The flame arrestor 104 prevents post- separation flame flashback. In several exemplary embodiments, the flame arrestor 104 includes one or more thermocouples and/or other sensors, which may be in communication with one or more controllers to monitor the temperature and/or other operating condition(s) of the flame arrestor 104 during the operation of the apparatus 76; in some exemplary embodiments, the one or more controllers may activate an alarm and/or take other action(s) in response to the monitoring; in several exemplary embodiments, the one or more controllers include the igniter control box 1 12. In several exemplary embodiments, the igniter 108 provides increased safety due to an increased elevation of flare, and the flame arrestor 104 provides integrated flare flashback prevention.

[0094] During operation, in several exemplary embodiments, to separate the solid and liquid materials from the gas materials in the multiphase flow, the vessel 90 is sized so that the lighter gas materials are permitted to rise or flow upwards towards the outlet pipe 98, and so that the heavier solid and liquid materials fall to the bottom of the vessel 90 for containment therein and/or drainage therefrom.

[0095] During operation, in several exemplary embodiments, the splitting of the multiphase flow into at least two different flow paths within the horizontally-extending portion 120f of the inlet pipe 120 reduces the flow velocities of the multiphase flow as it enters the internal region 128 (as indicated by the arrows 134 and 136), thereby improving the separation of the solid and liquid materials from the gas materials within the internal region 128. During operation, in several exemplary embodiments, the respective angular extensions of the elbow connections 120g and 120h further facilitate the dissipation or reduction of the flow velocities of the multiphase flow as it enters the internal region 128 (as indicated by the arrows 134 and 136), thereby further improving the separation of the solid and liquid materials from the gas materials within the internal region 128.

[0096] During operation, in several exemplary embodiments, the plates 130a and 130b operate as vortex breakers, preventing gas materials from entraining in the solid and liquid materials being drained from the vessel 90, or otherwise entering the drain pipe 1 10, via the duct 1 10c and the elbow connection HOd.

[0097] During operation, in several exemplary embodiments, if the level of the liquid materials within the vessel 90 reaches a predetermined level, the liquid- level switch 1 18 detects that the liquid level has reached the predetermined level. In an exemplary embodiment, in response to this detection, the liquid- level switch 1 18 causes one or more alarms to be activated and/or causes other action(s) to be taken. In an exemplary embodiment, the liquid- level switch 1 18 is in communication with a controller, and sends one or more signals to the controller in response to detecting that the liquid level has reached the predetermined level within the vessel 90; the controller may activate an alarm and/or take other action(s) in response to receiving the one or more signals from the liquid- level switch 1 18. In an exemplary embodiment, the controller in communication with the liquid-level switch 1 18 is, or includes, the igniter control box 1 12. In an exemplary embodiment, the predetermined level that the liquid-level switch 1 18 is adapted to detect is generally equal to about the height H of the liquid-level switch 1 18 within the internal region 128. In an exemplary embodiment, the height H of the liquid-level switch 1 18 within the internal region 128 is about 10 inches. In an exemplary embodiment, the predetermined level that the liquid-level switch 1 18 is adapted to detect is generally equal to about the height H of the liquid-level switch 1 18 within the internal region 128, and the height H is about 10 inches. In an exemplary embodiment, the predetermined level that the liquid- level switch 1 18 is adapted to detect is generally equal to about the height H of the liquid- level switch 1 18 within the internal region 128, the diameter of the vessel 90 is about 48 inches, the axial length of the vessel 90 is about 144 inches, and the height H of the liquid- level switch 1 18 within the internal region 128 is about 10 inches; in several exemplary experimental embodiments, it has been determined that the foregoing combination of dimensions ensures that the predetermined level (generally equal to the height H) is low enough to provide enough response time if the vessel 90 begins to experience overflow, but high enough to allow the apparatus 76 to operate freely, ensuring that a volume, within the internal region 28 and above the liquid-level switch 1 18, is sufficient for the separation of the solid and liquid materials from the gas materials in the multiphase flow. In several exemplary embodiments, the liquid-level switch 1 18 may operate in accordance with the foregoing when the valve 110b is closed, partially open, or completely open.

[0098] During the operation of the apparatus 76, in several exemplary embodiments, the guide wires 132a, 132b, 132c, and 132d secure and stabilize the igniter 108. In several exemplary embodiments, the guide wires 132a, 132b, 132c, and 132d secure and stabilize the igniter 108 during the installation of the apparatus 76 at the wellsite 78. The stabilization provided by the guide wires 132a, 132b, 132c, and 132d is facilitated by the vessel 90 being centered on the skid 88, and by the outlet pipe 98 being centered on the top of the vessel 90.

[0099] During operation, in several exemplary embodiments, due at least in part to the vessel 90, separation is achieved in a closed system, with post-separation dynamics ensuring that only vent gas is discharged to the vent pipe 106. More particularly, during operation, the cap flange 90d is connected to the access port 90c and the vessel 90 is a closed vessel, that is, closed to the atmosphere, with no part of the vessel being directly open to the atmosphere. Thus, separation is achieved in a closed system, with post-separation dynamics ensuring that only vent gas is discharged to the vent pipe 106.

[00100] In several exemplary embodiments, the one or more fluid lines 86 is a vent gas line, and the apparatus 76 functions both as a vent gas separator and a secondary containment flare system. The apparatus 76 effectively separates and contains solid and liquid carryover in the vent gas flowing through the fluid lines 86 and into the apparatus 76, while burning off the gas materials. In several exemplary embodiments, the apparatus 76 ensures the collection and storage of solid and liquid materials entrained in the vent gas. In several exemplary embodiments, the apparatus 76 is an integrated separator and secondary containment flare apparatus. In several exemplary embodiments, the apparatus 76 is an integrated vent gas separator and secondary containment flare apparatus. In several exemplary embodiments, the apparatus 76 is an integrated vent gas separator and flare stack.

[00101] In several exemplary embodiments, the above-described integration and vertical stack-up of the different components of the apparatus 76 reduces the footprint of the apparatus 76 to the footprint of the skid 88, thereby providing a compact structure. The apparatus 76 occupies a surface area at the wellsite 78 that is generally equal to the surface area that the skid 88 occupies at the wellsite 78. Further, the above-described integration and vertical stack-up of the different components of the apparatus 76 facilitates the installation of the apparatus 76. Still further, the above-described integration and vertical stack-up of the different components of the apparatus 76 facilitates the above-described operation of the apparatus 76 in that, for example, the heavier solid and liquid materials fall to the bottom of the vessel 90 for collection therewithin, and the lighter gas materials rise up out of the vessel 90, through the flame arrestor 104, through the vent pipe 106, and into the igniter 108.

[00102] In several exemplary embodiments, the configuration of the apparatus 76 described above and illustrated in Figures 9-12 and 15 may be referred to as an installation configuration of the apparatus 76. In an exemplary embodiment, the apparatus 76 has an installation configuration in which either the apparatus 76 is in fluid communication with the one or more fluid lines 86 (or another fluid line) and is able to operate in accordance with the foregoing, or the apparatus 76 is able to be placed in fluid communication with the one or more fluid lines 86 (or another fluid line) and, when so placed, is able to operate in accordance with the foregoing. In an exemplary embodiment, the apparatus has an installation configuration in which at least the flame arrestor 104 extends vertically and is connected to the vessel 90, the vent pipe 106 extends vertically and is connected to the flame arrestor 104 so that the flame arrestor 104 is vertically positioned between the vessel 90 and the vent pipe 106, and the igniter 108 extends vertically and is connected to the vent pipe 106 so that the vent pipe 106 is vertically positioned between the flame arrestor 104 and the igniter 108.

[00103] In an exemplary embodiment, as illustrated in Figures 16-18 with continuing reference to Figures 8-15, the apparatus 76 has a transportation configuration in which the flame arrestor 104, the vent pipe 106, and the igniter 108 do not extend vertically and are not vertically stacked on top of each other. Instead, in the transportation configuration: the flame arrestor 104 extends horizontally and is mounted on the side portion 88c of the skid 88 by being connected to the flame arrestor mounting brackets 96a and 96b on the side portion 88c of the skid 88; the vent pipe 106 extends horizontally over the side portion 88c and is connected to the vent pipe mounting brackets 1 14a and 1 14b; the igniter 108 extends horizontally and is mounted on the side portion 88c of the skid 88 by being connected to the igniter mounting brackets 94a and 94b on the side portion 88c of the skid 88; and the guide wires 132a, 132b, 132c, and 132d do not extend to the upper end portion of the igniter 108 from respective ones of the four comers defined by the skid 88. The transportation configuration of the apparatus 76 enables the apparatus 76 to be easily transported on a truck or other vehicle to the wellsite 78. The transportation configuration of the apparatus 76 reduces the volumetric envelope of the apparatus 76 to improve its transportability. In the transportation configuration of the apparatus 76, the flame arrestor 104, the vent pipe 106, and the igniter 108 can all be accessed at the side portion 88c of the skid 88. Therefore, only the side portion 88c of the skid 88 needs to be accessible to installation personnel and installation equipment such as, for example, forklifts or other devices. In an exemplary embodiment, in the transportation configuration of the apparatus 76, installation personnel, either manually or using a forklift or other device, can access any one of the flame arrestor 104, the vent pipe 106, and the igniter 108 by moving in a common direction towards the side portion 88c, as indicated by an arrow 142 in Figures 16 and 17.

[00104] In an exemplary embodiment, as illustrated in Figure 19 with continuing reference to Figures 1-18, a method of installing the apparatus 76 is generally referred to by the reference numeral 144. The method 144 includes at step 144a accessing the flame arrestor 104 at the side portion 88c of the skid 88 and disconnecting the flame arrestor 104 from the flame arrestor mounting brackets 96a and 96b. At step 144b, the flame arrestor 104 is connected to the concentric reducer 102 so that the flame arrestor 104 extends vertically. At step 144c, the horizontally-extending vent pipe 106 is accessed at the side portion 88c and disconnected from the vent pipe mounting brackets 1 14a and 1 14b. At step 144d, the vent pipe 106 is connected to the flame arrestor 104 so that the vent pipe 106 extends vertically. At step 144e, the igniter 108 is accessed at the side portion 88c and disconnected from the igniter mounting brackets 94a and 94b. At step 144f, the igniter 108 is connected to the vent pipe 106 so that the igniter 108 extends vertically. At step 144g, the guide wires 132a, 132b, 132c, and 132d are connected to the upper end portion of the igniter 108 and respective ones of the four corners of the skid 88. In several exemplary embodiments, the steps 144a, 144b, 144c, 144d, 144e, 144f, and 144g may be performed in different orders, simultaneously, sequentially, or any combination thereof. Regardless of the order of performance, the execution of the method 144 changes the configuration of the apparatus 76 from its transportation configuration shown in Figures 16-18 to its installation configuration shown in Figures 9-12 and 15.

[00105] In the foregoing description of certain embodiments, specific terminology has been resorted to for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes other technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as "left" and right", "front" and "rear", "above" and "below" and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms.

[00106] In this specification, the word "comprising" is to be understood in its "open" sense, that is, in the sense of "including", and thus not limited to its "closed" sense, that is the sense of "consisting only of. A corresponding meaning is to be attributed to the corresponding words "comprise", "comprised" and "comprises" where they appear.

[00107] In addition, the foregoing describes only some embodiments of the invention(s), and alterations, modifications, additions and/or changes can be made thereto without departing from the scope and spirit of the disclosed embodiments, the embodiments being illustrative and not restrictive.

[00108] Furthermore, invention(s) have described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention(s). Also, the various embodiments described above may be implemented in conjunction with other embodiments, e.g., aspects of one embodiment may be combined with aspects of another embodiment to realize yet other embodiments. Further, each independent feature or component of any given assembly may constitute an additional embodiment.

Claims

WHAT IS CLAIMED IS:

1. An apparatus, comprising:

a separator vessel adapted to separate solid and liquid materials from gas materials;

a flame arrestor in fluid communication with the separator vessel and through which the gas materials are adapted to flow; and

a flare stack adapted to burn off the gas materials, wherein the flare stack is positioned so that the flame arrestor is vertically positioned between the separator vessel and the flare stack, and wherein the flare stack comprises:

a vent pipe in fluid communication with the flame arrestor and positioned so that the flame arrestor is vertically positioned between the separator vessel and vent pipe; and

an igniter in fluid communication with the vent pipe, wherein the igniter is positioned so that the vent pipe is vertically positioned between the flame arrestor and the igniter.

2. The apparatus of claim 1, further comprising a skid on which the separator vessel, the flame arrestor, and the flare stack are mounted;

wherein the flame arrestor is positioned so that the separator vessel is vertically positioned

between the skid and the flame arrestor.

3. The apparatus of claim 2, further comprising one or more guide wires extending from the skid to the flare stack to secure and stabilize the igniter.

4. The apparatus of claim 2, further comprising an outlet pipe generally centered on the top of the separator vessel and extending upward therefrom;

wherein the flame arrestor is in fluid communication with the outlet pipe and is positioned so that the outlet pipe is vertically positioned between the separator vessel and the flame arrestor; and

wherein the separator vessel is generally centered on the skid.

5. The apparatus of claim 4, wherein the apparatus comprises one or more guide wires to secure and stabilize the igniter, each of the one or more guide wires extending to the flare stack from the skid; and wherein the centering of the outlet pipe on the top of the separator vessel, and the centering of the separator vessel on the skid, facilitates the securement and stabilization of the igniter by the one or more guide wires.

The apparatus of claim 1 , wherein the separator vessel defines an internal region and comprises an access port and a cap flange removably connected thereto;

wherein the access port provides access to the internal region; and

wherein, when the solid and liquid materials are separated from the gas materials, the cap flange is connected to the access port and the separator vessel is a closed vessel that is closed to the atmosphere.

The apparatus of claim 1 , wherein the separator defines an internal region in which the solid and liquid materials are adapted to be separated from the gas materials;

wherein the apparatus further comprises an inlet pipe via which the solid, liquid, and gas

materials are adapted to flow into the internal region;

wherein the inlet pipe comprises a first connection that extends angularly towards the separator vessel and is connected thereto;

wherein the angular extension of the first connection defines an angle from a horizontal plane; and

wherein the angle from the horizontal plane ranges from greater than 0 degrees to less than 90 degrees.

The apparatus of claim 7, wherein at least respective portions of the solid, liquid, and gas materials are adapted to flow into the internal region, via the first connection, in a generally angular direction that corresponds to the first angle; and

wherein the first angle ranges from about 10 degrees to about 80 degrees.

materials are adapted to flow into the internal region;

wherein the inlet pipe comprises a horizontally-extending portion that extends axially along the separator vessel, the horizontally-extending portion comprising first and second connections located at opposing ends, respectively, of the horizontally- extending portion; wherein the first and second connections are connected to the separator vessel;

wherein the solid, liquid, and gas materials are adapted to flow into the internal region via the first and second connections.

10. The apparatus of claim 9, wherein each of the first and second connections extends angularly towards the separator vessel;

wherein each of the angular extensions of the first and second connections defines an angle from a horizontal plane; and

1 1. A system at a wellsite, the system comprising:

one or more separators adapted to be in fluid communication with a wellbore at the wellsite; one or more vent gas lines in fluid communication with the one or more separators; and an integrated vent gas separator and flare stack, comprising:

a skid;

a vessel mounted on the skid, in fluid communication with the one or more vent gas lines, and adapted to separate solid and liquid materials from gas materials;

a flame arrestor in fluid communication with the vessel and positioned so that the vessel is vertically positioned between the skid and the flame arrestor; and

a flare stack in fluid communication with the flame arrestor and adapted to burn off the gas materials, wherein the flare stack is positioned so that the flame arrestor is vertically positioned between the vessel and the flare stack.

12. The system of claim 1 1, wherein the flare stack comprises a vent pipe and an igniter connected thereto.

13. The system of claim 12, further comprising one or more guide wires extending from the skid to the flare stack;

wherein the one or more guide wires secure and stabilize the igniter.

14. The system of claim 1 1, wherein the vessel defines an internal region and comprises an access port and a cap flange removably connected thereto;

wherein the access port provides access to the internal region; and wherein, when the solid and liquid materials are separated from the gas materials, the cap flange is connected to the access port and the vessel is a closed vessel that is closed to the atmosphere.

15. The system of claim 1 1, wherein the one or more separators comprise at least one of a mud-gas separator and a shale-gas separator.

16. A kit which, when assembled, is adapted to process a multiphase flow at a wellsite, the

multiphase flow comprising solid, liquid, and gas materials, the kit comprising:

a skid;

a vessel mounted on the skid and into which the multiphase flow is adapted to flow to separate the solid and liquid materials from the gas materials, wherein the mounting of the vessel on the skid defines opposing first and second side portions of the skid, and wherein the vessel is positioned between the opposing first and second side portions of the skid; an inlet pipe connected to the vessel and via which the multiphase is adapted to flow into the vessel, wherein at least a portion of the inlet pipe extends above the first side portion; a flame arrestor;

a vent pipe; and

an igniter;

wherein the kit has:

a first configuration in which:

each of the flame arrestor, the vent pipe, and the igniter either is mounted on the second side portion of the skid or extends over the second side portion of the skid; and

each of the vent pipe and the igniter extends horizontally;

and

a second configuration in which:

the flame arrestor extends vertically and is positioned so that the vessel is

vertically positioned between the skid and the flame arrestor;

the gas materials are adapted to flow through the flame arrestor;

the vent pipe extends vertically and is positioned so that the flame arrestor is vertically positioned between the vessel and the vent pipe;

the gas materials are adapted to flow through the vent pipe; the igniter extends vertically and is positioned so that the vent pipe is vertically positioned between the flame arrestor and the igniter;

and

the igniter is adapted to burn off the gas materials.

17. The kit of claim 16 wherein, when the kit is in the first configuration:

one of the vent pipe and the igniter is mounted on the second side portion of the skid;

the other of the vent pipe and the igniter extends above the second side portion of the skid; and the flame arrestor is mounted on the second side portion of the skid.

18. The kit of claim 16 wherein the vessel defines an internal region and comprises an access port and a cap flange removably connected thereto;

wherein the access port provides access to the internal region; and

wherein, when the solid and liquid materials are separated from the gas materials, the cap flange is connected to the access port and the vessel is a closed vessel that is closed to the atmosphere.

19. A method, comprising:

providing a skid and a separator vessel mounted on the skid, wherein the mounting of the

separator vessel on the skid defines opposing first and second side portions of the skid, wherein the separator vessel is positioned between the opposing first and second side portions of the skid, and wherein each of a flame arrestor, a horizontally-extending vent pipe, and a horizontally-extending igniter either is mounted on the second side portion of the skid or extends over the second side portion of the skid;

accessing the flame arrestor at the second side portion of the skid;

connecting the flame arrestor to the separator vessel so that the flame arrestor extends vertically; accessing the horizontally-extending vent pipe at the second side portion of the skid;

connecting the vent pipe to the flame arrestor so that the vent pipe extends vertically;

accessing the horizontally-extending igniter at the second side portion of the skid; and connecting the igniter to the vent pipe so that the igniter extends vertically.

20. The method of claim 19, further comprising connecting one or more guide wires between the igniter and the skid to secure and stabilize the igniter.

21. The method of claim 19, wherein an inlet pipe is connected to the separator vessel and at least a portion of the inlet pipe extends over the first side portion of the skid; and

wherein the method further comprises:

connecting one or more fluid lines to the inlet pipe;

conveying a multiphase flow into the separator vessel via the one or more fluid lines and the inlet pipe, the multiphase flow comprising solid, liquid, and gas materials;

separating, using the separator vessel, the solid and liquid materials from the gas materials; conveying the gas materials upwardly into the flame arrestor; and

conveying the gas materials upwardly from the flame arrestor and into the igniter.

22. The method of claim 21, wherein the one or more fluid lines comprise at least one vent gas line that is in fluid communication with one of a mud-gas separator and a shale-gas separator.

23. The method of claim 19, wherein the separator vessel defines an internal region and comprises an access port and a cap flange removably connected thereto, and wherein the access port provides access to the internal region.