Booster-ejector system for capturing and recycling leaked fluids

Abstract

The booster-ejector system captures and recycles leakage fluid from the process. When the process pressure differential (head) exceeds a threshold, the ejector system uses drive fluid from the process high-pressure (HP) region to capture and compress the leakage fluid and direct it to the low-pressure (LP) region. When the head falls below the threshold, the controller reconfigures the piping system and activates the leakage pump to pump the leakage fluid to the LP region. The system can include only one ejector or multiple ejectors, which can be coupled so that the diffuser output of each ejector is directed to the suction input of the next ejector. At least one of the ejectors can include interchangeable throats that can impart a rotational component to the fluid. The HP and LP regions can be the output and input of the compressor, respectively.

Description

[Technical Field]

[0001] Related Applications

[0001] This application claims the benefit of U.S. Patent Application No. 18 / 104,347, filed February 1, 2023 (now U.S. Patent No. 11,835,183, issued December 5, 2023), which is incorporated by reference herein in its entirety for all purposes.

[0002] FIELD OF THE INVENTION

[0002] The present invention relates to a system for treating leaked fluids, and more particularly to a system for recapturing and compressing leaked fluids. [Background technology]

[0003] Background of the Invention

[0003] Systems that transport, compress, circulate, and / or store process fluids are often prone to leaks. This can be due to deterioration of fittings, seals, or other components over time, and / or can be inherent in the design of the system. For example, end-face liquid mechanical seals or end-face dry gas mechanical seals, by design, always have a small amount of leakage fluid due to the non-contacting action of the seal end faces.

[0004] 1A, a simplified example is shown in which a liquid, such as a hydrocarbon gas or liquefied natural gas (LNG) gas vaporized at a relatively low pressure, enters an input 100 of a compressor 102. The pressurized gas is then delivered from an outlet 104 of the compressor 102 to a gas distribution system or a compressed gas reservoir for transport to a final destination. In this simplified example, the compressor 102 includes an impeller (not shown) attached to a rotating shaft 106 driven by a motor 108. A dry gas seal 110 is provided to reduce leakage of gas from the compressor 102 along the rotating shaft 106. However, the dry gas seal 110 inevitably allows a small amount of gas to leak, which is directed into a leakage line 112. In similar situations, a slow leak can occur due to defects or wear in a fitting or attachment.

[0005] In many applications, it is acceptable and tolerable to release small amounts of leaked process fluid (also referred to herein as "leakage fluid") into the environment. For example, the system shown in FIG. 1A simply vents the leaking gas from the leak line 112 to an atmospherically "safe" location.

[0006] However, in other applications, it is desirable to avoid the release of even small amounts of leaking process fluid because the process fluid is toxic and / or harmful to the environment. In some of these cases, an inert "buffer" fluid at a higher pressure than the process fluid is used at the expected or potential leak point, so that any leakage is a leakage of buffer fluid into the process, rather than a leakage of process fluid into the environment. One example would be introducing pressurized nitrogen gas into a housing surrounding an end-face dry gas seal. While this approach can be effective, it has the disadvantage of mixing the buffer fluid with the process fluid. Additionally, the requirement to provide buffer gas adds cost and complexity to the system by requiring a source of pressurized buffer gas to be provided and replenished as needed.

[0007]

[0007] In the case of hydrocarbon process fluids, another approach is to simply collect the leaking fluid and "set it on fire," i.e., burn it so that any toxic hydrocarbons are converted to water and carbon dioxide. However, this approach has the disadvantage that the leaking fluid is wasted. Furthermore, carbon dioxide, while not toxic, is an undesirable greenhouse gas, and its release can be harmful to the environment and subject to increasingly stringent government-imposed restrictions and regulations.

[0008] 1B, yet another approach is to collect the leakage fluid, compress it using a secondary pump or compressor 114, and then reintroduce it into the process stream, such as the input 100 of the primary compressor 102. In the example shown, the secondary compressor is a reciprocating booster 114, which may be an appropriate choice due to its low pressure (less than 25 psi) and flow rate (less than 4 SCFM), and is less prone to leakage than a rotary booster. This approach has the advantage that the leakage fluid is not wasted and is not introduced into the environment in any form. However, if the leakage rate is low, the energy cost of operating the pump or compressor may be prohibitive. Summary of the Invention [Problem to be solved by the invention]

[0009]

[0009] Therefore, what is needed is a system and method for treating leaking fluids that reduces or avoids the release of the leaking fluid or its combustion products into the environment while minimizing energy costs. [Means for solving the problem]

[0010] Summary of the Invention

[0010] The present invention is a system and method for recapturing and recycling leaking fluids while reducing or avoiding release of the leaking fluids or their combustion products to the environment and minimizing energy costs. The present invention is applicable to systems in which process fluids exist at both high and low pressures, such as systems including a compressor that compresses the process fluid and has a relatively low pressure fluid input and a relatively high pressure fluid output.

[0011] It should be noted that examples and explanations may be presented herein with reference to a system for compressing a gas, such as natural gas, and capturing and recycling leaked quantities of the gas. However, it should be understood that the present disclosure applies equally to systems in which the process fluid is a liquid, unless the context requires otherwise. Examples are presented herein in which the leaked fluid originates from a compressor, for example, a shaft seal, a fitting, or a coupling within the compressor. However, it should be understood that in general, the present invention is applicable to recapturing and recycling leaked process fluid originating from any leak source and from another location where the process fluid is at a lower pressure, so long as a high-pressure source of the process fluid is available.

[0012]

[0012] According to the present invention, an ejector is implemented as a primary capture mechanism for capturing and recompressing leakage fluid. A higher pressure fluid, e.g., the output of a compressor, is provided as the "drive fluid" for the ejector, while the suction input of the ejector is connected to a leakage fluid source. The ejector then functions to draw in the leakage fluid, which is entrained in the drive fluid, after which the mixture of drive fluid and leakage fluid, referred to herein as the "process fluid mixture," is compressed in the diffuser section of the ejector and delivered to a location where the process fluid is at a lower pressure, e.g., the input of a compressor.

[0013]

[0013] This approach is very energy efficient in that the ejector is simple in design and consumes no power. Because the leakage fluid flow rate is low and the resulting flow required for the drive fluid is low, the loss in system efficiency due to the diversion of high pressure fluid to the ejector is negligible.

[0014]

[0014] Naturally, the ability of the ejector to apply suction to draw in leakage fluid, compress it, and reintroduce it into the process depends on establishing a significant pressure differential, or "head," between the motive fluid input and the diffuser output. Thus, if the supply of high-pressure process fluid is interrupted, the ejector will no longer be able to capture the leakage fluid. For example, if high-pressure process fluid is drawn from the compressor output, the ejector will not function when the compressor is not running at full capacity, either because it is operating intermittently, operating only slowly (e.g., during start-up, shutdown preparation, or standby mode), or is shut down for maintenance.

[0015] One possibility is to redirect the motive fluid input and / or the diffuser output to an alternative location within the process. For example, if multiple compressors are implemented in a process, if a first compressor is temporarily unavailable, it may be possible to redirect the output of a second compressor to the motive fluid input of the ejector. Nevertheless, it may be impossible to guarantee that a high-pressure source of process fluid is always available. Therefore, the system of the present invention further includes a leakage compressor or pump as a secondary capture mechanism, referred to herein as a "leakage booster." When no high-pressure process fluid source is available, a remotely operated valve is controlled by the controller to redirect leakage fluid from the ejector to the leakage booster, which is then powered to capture the leakage fluid and recycle it to the compressor input or another destination within the process.

[0016] During normal operation, when the ejector is running at full capacity, no power is supplied to the leakage booster, i.e., the leakage booster is switched off, so no power is consumed by the system. Thus, power is consumed by the present invention only when high-pressure process fluid is not available, which in many applications is infrequent and of relatively short duration.

[0017]

[0017] Leakage fluids are typically at low pressure when they enter the ejector due to expansion after leaking through seals, fittings, fittings, or other structures. This pressure is further reduced by the suction of the ejector. Similarly, the pressure of the motive fluid is significantly reduced as it accelerates through the throat of the ejector. Therefore, the process fluid mixture must be significantly compressed so that it reaches a pressure above the compressor input fluid pressure or other "low pressure" point. Otherwise, the process fluid would tend to flow backward from the compressor inlet or other "low pressure" point into the ejector diffuser.

[0018] In an embodiment, if a single ejector cannot sufficiently compress the process fluid mixture, a second ejector is implemented whereby the output of the first ejector is directed to the suction input of the second ejector, thereby providing the higher pressure process fluid as the drive fluid for both the first and second ejectors. This scheme can be extended to three or more ejectors as needed.

[0019]

[0019] Embodiments further increase the efficiency of one or more ejectors by implementing a "cyclone" technique that imparts rotational motion to the drive gas as it flows through the ejector. This approach serves to increase the local velocity of the drive fluid as it mixes with the leakage fluid while slowing the longitudinal flow of the fluid mixture through the diffuser. As a result, the pressure at the suction input of the ejector is maintained or reduced, while the pressure of the fluid mixture at the output of the ejector is increased.

[0020]

[0020] In many cases, implementing the present invention for different specific applications requires optimizing the throat design in terms of its inlet diameter, nozzle constriction, and the like. In many cases, the ejector's diffuser and other elements are satisfactory over a wide range of operating conditions, thereby requiring only throat modification. It is possible for an ejector's throat to wear, be damaged, or become clogged, while the rest of the ejector remains intact. Therefore, embodiments of the present invention incorporate a "modular" ejector that includes a replaceable throat. This approach allows for only the replaceable throat to be required in large quantities, and for a relatively small number of ejectors to be maintained in inventory in anticipation of customer needs. Whenever a system needs to be configured for a new customer or an already deployed system needs to be re-adapted to new operating conditions, it is only necessary to select the optimal throat and install it in an otherwise "universal" ejector design. Similarly, if an ejector's throat wears, is damaged, or becomes clogged, it can be easily replaced without removing the entire ejector from the system, requiring only a spare throat, not a spare ejector.

[0021]

[0021] A first general aspect of the present invention is a booster-ejector system configured to capture and recycle leakage fluid when it escapes from a process that typically includes a high-pressure (HP) region containing process fluid at high pressure and a low-pressure (LP) region containing process fluid at low pressure. The system includes an ejector system (ES) having an ES drive fluid input, an ES leakage fluid input, and an ES fluid mixture output, the ejector system including a first ejector (FE) having an FE drive fluid input connected to the ES drive fluid input, an FE suction input connected to the ES leakage fluid input, an FE mixing chamber, and an FE diffuser, the first ejector configured to draw leakage fluid into the FE mixing chamber through the FE suction input, receive drive fluid into the FE mixing chamber through the FE drive fluid input, entrain the leakage fluid in the drive fluid, and compress the resulting fluid mixture as it flows out of the first ejector through the FE diffuser.

[0022]

[0022] The system further includes: a first throat in the FE mixing chamber, wherein the drive fluid is directed through the first throat as it enters the FE mixing chamber, the first throat including a constriction nozzle configured to accelerate the flow rate of the drive fluid as it flows through the first throat; an electric leakage fluid booster having a booster inlet and a booster outlet, the electric leakage fluid booster configured to pump the leakage fluid to the LP region; and a controller configured to control the leakage fluid pump and piping system according to the process fluid pressure difference between the HP and LP regions of the process, referred to herein as the "head" of the ejector, whereby when the ejector head exceeds a specified value, no power is consumed by the leakage fluid pump and the leakage fluid flows through the ejector system to the LP region, and when the ejector head falls below the specified value, the leakage fluid pump operates to pump the leakage fluid to the LP region.

[0023] In an embodiment, the first ejector is configured to allow the first throat to be replaced by the second throat.

[0024] In any of the above-described embodiments, the first throat may be configured to impart a rotational component of motion to the drive fluid as it exits the first throat.

[0025]

[0025] In any of the above-described embodiments, the leakage fluid pump may be a reciprocating pump.

[0026] In any of the above-described embodiments, the HP and LP regions may be the input and output, respectively, of a fluid compressor.

[0027]

[0027] In any of the above-described embodiments, the ejector system may further include a second ejector, the driving fluid input of the second ejector being connected to the ES driving fluid input, the suction input of the second ejector being connected to the FE diffuser, and the diffuser of the second ejector being fluidly connected to the ES fluid mixture output.

[0028]

[0028] In any of the above-described embodiments, the controller may be further configured to control the ejector head.

[0029] A second general aspect of the present invention is a method for capturing and recycling leakage fluid as it escapes from a process that typically includes a high-pressure (HP) zone containing the process fluid at high pressure and a low-pressure (LP) zone containing the process fluid at low pressure. The method includes providing a booster-ejector system according to any embodiment of the first general aspect, determining, by a controller, a process fluid pressure differential between the HP and LP zones of the process, referred to herein as the "head" of the ejector, when the ejector head exceeds a designated value, configuring, by the controller, the leakage fluid booster and piping system in a first mode in which power is not consumed by the leakage fluid pump and the leakage fluid flows through the ejector system to the LP zone, and configuring, by the controller, the leakage fluid booster and piping system in a second mode in which the leakage fluid booster operates to pump the leakage fluid to the LP zone when the compressor head falls below the designated value.

[0030]

[0030] The embodiment further includes replacing the first throat with a second throat.

[0031] In any of the above-described embodiments, the first throat may be configured to impart a rotational component of motion to the drive fluid as it exits the first throat.

[0032]

[0032] In any of the above-described embodiments, the leakage fluid booster may be a reciprocating booster.

[0033] In any of the above-described embodiments, the HP and LP regions may be the input and output, respectively, of a fluid compressor.

[0034]

[0034] In any of the above-described embodiments, the ejector system may further include a second ejector, the drive fluid input of the second ejector being connected to the ES drive fluid input, the suction input of the second ejector being connected to the FE diffuser, and the diffuser of the second ejector being fluidly connected to the ES fluid mixture output.

[0035] Any of the above-described embodiments may include controlling the ejector head with a controller.

[0036]

[0036] Also, in any of the above-described embodiments, providing the booster-ejector system may include providing a first ejector housing including a first ejector drive fluid input, a first ejector suction input, a first ejector mixing chamber and a first ejector diffuser, selecting a throat suitable for the operating conditions of the process, and mounting the throat within the ejector housing, thereby providing the first ejector of the booster-ejector system.

[0037]

[0037] The features and advantages described herein are not all-inclusive, and many additional features and advantages will become apparent to those skilled in the art, especially in light of the drawings, the specification, and the claims. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and instructional purposes, and is not intended to limit the scope of the inventive subject matter. [Brief explanation of the drawings]

[0038] BRIEF DESCRIPTION OF THE DRAWINGS [Figure 1A]

[0038] FIG. 1 is a simplified diagram of leakage gas discharged from a compressor according to the prior art. [Figure 1B]

[0039] 1 is a simplified diagram of leakage gas being recycled to the compressor inlet by a leakage pump according to the prior art; [Figure 2]

[0040] 10 illustrates recycling leakage fluid to the compressor inlet by an ejector, according to a partial embodiment of the present invention. [Figure 3]

[0041] 1 illustrates an embodiment of the present invention including only one ejector combined with a controller and a leakage fluid pump. [Figure 4]

[0042] 1 illustrates one embodiment of the present invention, including an ejector system including two ejectors combined with a controller and a leakage booster. [Figure 5A]

[0043] FIG. 1 is a cross-sectional view, to scale, of an ejector including a replaceable throat with a cyclonic fluid outlet, according to one embodiment of the present invention. [Figure 5B]

[0044] FIG. 5B is a cross-sectional perspective view, drawn to scale, of the ejector of FIG. 5A. [Figure 5C]

[0045] FIG. 5C is a scaled, exploded perspective view of the embodiment of FIGS. 5A and 5B. [Figure 5D]

[0046] FIG. 6 is an enlarged perspective view, drawn to scale, of the throat of FIGS. 5A to 5C. [Figure 6]

[0047] FIG. 1 is a cross-sectional view, to scale, of an ejector system including three ejectors, according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] Detailed Description

[0048] The present invention is a system and method for recapturing and recycling leaking fluids while reducing or avoiding the release of leaking fluids or their combustion products into the environment and minimizing energy costs. The present invention is applicable to systems where process fluids exist at both high and low pressures, such as systems including a compressor that compresses a process fluid and has a relatively low pressure fluid input and a relatively high pressure fluid output.

[0040]

[0049] It should be noted that examples and explanations may be presented herein with reference to a system that compresses a gas, such as natural gas, and captures and recycles leaked quantities of the gas. However, it should be understood that the present disclosure applies equally to systems in which the process fluid is a liquid, unless the context requires otherwise. Examples are presented herein in which the leaked fluid originates from a compressor, e.g., a shaft seal, a fitting, or a coupling within the compressor. However, it should be understood that in general, the present invention is applicable to recapturing and recycling leaked process fluid originating from any leak source, as well as from another location where the process fluid is present at a lower pressure, so long as a high-pressure source of the process fluid is available.

[0041]

[0050] 2, in accordance with the present invention, an ejector 200 is implemented as a primary capture mechanism for capturing and recompressing leakage fluid. In the illustrated example, process fluid from the output 104 of the compressor 102 is provided to a "drive fluid" input 202 of the ejector 200, while a suction input 204 of the ejector 200 is connected to the leakage fluid source 110. The ejector 200 then functions to draw in the leakage fluid, which is entrained in the drive fluid; the mixture of drive fluid and leakage fluid, referred to herein as the "process fluid mixture," is then compressed in the ejector's diffuser section 206 and returned to a point of low process fluid pressure, which in the illustrated example is the input of the compressor.

[0042]

[0051] This approach is very energy efficient in that the ejector 200 is a simple design, has no moving parts, and consumes no power. Because of the low leakage fluid flow rate and the resulting low motive fluid flow requirements, the loss in compressor 102 efficiency due to the diversion of a small amount of output fluid to the ejector 200 is negligible.

[0043]

[0052] 2 to apply suction to draw in leaking fluid, compress it, and reintroduce it into the input 100 of the compressor 102 is dependent upon establishing a significant pressure differential, or "head," between the compressor input 100 and output 104. Thus, when the compressor 102 is not running at full capacity, either because it is operating intermittently, operating only slowly (e.g., during start-up, shutdown preparation, or standby mode), or is shut down for maintenance, leakage may still occur, but the ejector 200 will not be able to capture it.

[0044]

[0053] One possibility is to redirect the motive fluid input 202 and / or the diffuser output 206 of the ejector 200 to an alternative location within the process. For example, if multiple compressors 102 are implemented in a process, if a first compressor 102 is temporarily unavailable, it may be possible to redirect the output of a second compressor to the motive fluid input 202 of the ejector 200. Nevertheless, it may not be possible to guarantee that a high-pressure source of process fluid is always available.

[0045]

[0054] 3, the system of the present invention further includes a leakage compressor or pump 300 as a secondary capture mechanism, referred to herein as a "leakage booster" 300. When a source of high pressure process fluid is not available, for example when the compressor 102 of FIG. 3 is not running at full capacity, a remotely operated valve 302 is actuated by a controller 304 to divert leakage fluid from the ejector 200 to the leakage pump 300, and power is applied to the leakage booster 300 to capture the leakage fluid and return it to the input 100 of the compressor 102.

[0046]

[0055] During normal operation, when the compressor 102 and ejector 200 of Figure 3 are running at full capacity, no power is directed to the leakage booster 300, i.e., the leakage pump 300 is switched off, and therefore no power is consumed by the system. Thus, power is consumed with the embodiment of Figure 3 only during periods when the compressor 102 is not running at full capacity, which in many applications will be infrequent and of relatively short duration. In the embodiment of Figure 3, the controller 304, which controls the operation of the valve 302 and the switching on and off of the leakage booster 300, is coordinated with or controlled by the operation of the compressor 102 such that the system automatically switches between the ejector 200 and the leakage pump 300 depending on the operating mode of the compressor 102.

[0047]

[0056] The leakage fluid is typically at a low pressure when it enters the ejector input 204 due to expansion after leaking through the seal or other structure 110. This pressure is further reduced by the suction of the ejector 200. Similarly, the pressure of the motive fluid is significantly reduced as it accelerates through the throat of the ejector 200. Therefore, significant compression of the process fluid mixture is required so that it exceeds the process fluid pressure when it reaches the input 100 of the compressor 102. Otherwise, in the embodiment of FIG. 3, the process fluid would tend to flow in the reverse direction from the inlet 100 of the compressor 102 to the diffuser 206 of the ejector 200.

[0048]

[0057] 4, in an embodiment, if a single ejector 200 is not able to sufficiently increase the pressure of the process fluid mixture, a second ejector 400 is implemented whereby the output of the first ejector 200 is directed to a suction input 404 of the second ejector 400, such that process fluid from a high-pressure source, for example fluid from the output 104 of the compressor 102 in FIG. 3, is supplied to the motive fluid inputs 202, 402 of both the first ejector 200 and the second ejector 400. The output of a diffuser 406 of the second ejector 400 is then directed to the input 100 of the compressor 102. In an embodiment, multiple ejectors 200, 400 are combined in an ejector "system" 408 that receives fluid from a high-pressure process fluid source, such as the outlet 104 of the compressor 102, at a system drive fluid input 410, passes leakage fluid through a system leakage fluid inlet 412, and directs the combined drive and leakage fluids through a system fluid mixture outlet 414 to the inlet 100 of the compressor 102. This scheme can be extended to more than two ejectors as needed.

[0049]

[0058] 5A and 5B are cross-sectional side and perspective views of an ejector 200 according to one embodiment of the present invention. It can be seen that both the drive fluid input 202 and the leakage fluid input 204 lead to a "suction chamber" 500 of the ejector 200, where the two gases mix before being accelerated and pressurized in the diffuser section 206 of the ejector 200. In particular, the drive fluid input 202 directs the drive fluid through a "throat" 502 contained within the mixing chamber 500.

[0050]

[0059] In many cases, implementation of the present invention for different specific applications requires optimization of the design of the throat 502 in terms of its inlet diameter, nozzle constriction, etc. In many cases, the diffuser 206 and other elements of the ejector 200 are satisfactory for a wide range of operating conditions, thereby requiring only modifications to the throat 502. It may occur that the throat 502 of the ejector 200 becomes worn, damaged, or clogged while the rest of the ejector 200 remains intact.

[0051]

[0060] Thus, referring to the exploded perspective view of FIG. 5C , an embodiment of the present invention incorporates a “modular” ejector 200 that includes a replaceable throat 502. In this manner, only the replaceable throat 502 is needed in large quantities, allowing a relatively small number of ejectors 200 to be maintained in inventory in anticipation of customer needs. Whenever a system needs to be configured for a new customer or an already deployed system needs to be re-adapted to new operating conditions, the optimal throat 502 simply needs to be selected and installed with the otherwise “universal” ejector design. Similarly, if the throat 502 of an ejector 200 becomes worn, damaged, or clogged, it can be easily replaced without removing the entire ejector 200 from the system, requiring only a spare throat 502, not the entire ejector 200.

[0052]

[0061] FIG. 5D is an enlarged perspective view of the throat 502 of FIGS. 5A-5C. It can be seen from the drawing that the throat 502 terminates with a restricted "nozzle" 504. The illustrated embodiment further enhances the efficiency of the ejector 202 by implementing "cyclone" technology by including an additional circulating fluid outlet 506 that imparts a rotational motion to the drive gas as the drive gas flows out of the throat 502. This approach serves to increase the local velocity of the drive fluid when the drive fluid mixes with the leakage fluid, while slowing down the longitudinal flow of the fluid mixture through the diffuser 206. As a result, the pressure at the suction inlet 202 of the ejector 200 is maintained or decreased, while the pressure of the fluid mixture at the output of the ejector 200 increases.

[0053]

[0062] As described above with reference to FIG. 4, embodiments of the present invention include a plurality of ejectors 200 that operate in series to achieve sufficient pressurization of the mixture of drive gas and leakage fluid before being reinjected into the input 100 of the compressor 102 or other locations of low process fluid pressure. FIG. 6 shows a single ejector system 600 with three ejectors in one embodiment of the present invention.

[0054]

[0063] The foregoing description of embodiments of the present invention has been presented for purposes of illustration and description. Every page of this submission and all of its content, whether characterized, identified, or numbered, is considered to be a substantial part of this application for all purposes, regardless of the form or arrangement within this application. This specification is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of this disclosure.

[0055]

[0064] Although the present application is presented in a limited number of forms, the scope of the present invention is not limited to these forms and various modifications and alterations are possible. The present disclosure presented herein does not explicitly disclose all possible combinations of features within the scope of the present invention. Features disclosed herein for various embodiments are generally interchangeable and may be combined in any combination that is not self-contradictory without departing from the scope of the present invention. In particular, limitations presented in the following dependent claims may be combined with their corresponding independent claims in any number and in any order, without departing from the scope of the present disclosure, as long as the dependent claims are not logically incompatible with each other.

Claims

1. 1. A booster-ejector system configured to capture and recycle leakage fluid as it escapes from a process comprising a high pressure (HP) region typically containing a process fluid at a high pressure, and a low pressure (LP) region typically containing said process fluid at a low pressure, comprising: an ejector system (ES) having an ES drive fluid input, an ES leakage fluid input, and an ES fluid mixture output, including a first ejector (FE) having an FE drive fluid input connected to the ES drive fluid input, an FE suction input connected to the ES leakage fluid input, an FE mixing chamber, and an FE diffuser, the first ejector configured to draw the leakage fluid into the FE mixing chamber through the FE suction input, receive drive fluid into the FE mixing chamber through the FE drive fluid input, entrain the leakage fluid in the drive fluid, and compress the resulting fluid mixture as it exits the first ejector through the FE diffuser; a first throat contained within the FE mixing chamber, the drive fluid being directed through the first throat as it enters the FE mixing chamber, the first throat including a constricting nozzle configured to accelerate a velocity of the drive fluid flow as the drive fluid flows through the first throat; an electric leakage fluid booster having a booster inlet and a booster outlet, the electric leakage fluid booster configured to pump the leakage fluid to the LP region; a controller configured to control the leakage fluid booster and piping system according to a process fluid pressure difference between the HP and LP zones of the process, referred to herein as the "head" of the ejector, whereby when the ejector head exceeds a designated value, power is not consumed by the leakage fluid pump and the leakage fluid flows through the ejector system to the LP zone, and when the ejector head falls below the designated value, the leakage fluid booster operates to pump the leakage fluid to the LP zone; A booster-ejector system including:

2. The system of claim 1 , wherein the first ejector is configured to allow the first throat to be replaced by a second throat.

3. The system of claim 1 or 2, wherein the first throat is configured to impart a rotational component of motion to the driving fluid as it exits the first throat.

4. The system of any one of claims 1 to 3, wherein the leakage fluid booster is a reciprocating pump.

5. The system of any one of claims 1 to 4, wherein the HP and LP sections are the input and output, respectively, of a fluid compressor.

6. 6. The system of claim 1, wherein the ejector system further includes a second ejector, a drive fluid input of the second ejector connected to the ES drive fluid input, a suction input of the second ejector connected to the FE diffuser, and a diffuser of the second ejector in fluid communication with the ES fluid mixture output.

7. The system of any one of claims 1 to 6, wherein the controller is further configured to control the ejector head.

8. 1. A method for capturing and recycling a leakage fluid as it escapes from a process comprising a high pressure (HP) zone, typically containing a process fluid at a high pressure, and a low pressure (LP) zone, typically containing said process fluid at a low pressure, comprising: providing a booster-ejector system according to claim 1; determining, by the controller, a process fluid pressure differential between the HP and LP regions of the process, referred to herein as the "head" of the ejector; When the head of the ejector exceeds a designated value, the controller sets the leakage fluid booster and the piping system in a first mode in which no power is consumed by the leakage fluid booster and the leakage fluid flows through the ejector system to the LP area; when the head of the compressor falls below the specified value, the controller sets the leakage fluid booster and the piping system in a second mode in which the leakage fluid booster operates to pump the leakage fluid to the LP area; A method comprising:

9. The method of claim 8 further comprising replacing the first throat with a second throat.

10. 10. The method of claim 8 or 9, wherein the first throat is configured to impart a rotational component of motion to the driving fluid as it exits the first throat.

11. The method according to any one of claims 8 to 10, wherein the leakage fluid booster is a reciprocating booster.

12. The method according to any one of claims 8 to 11, wherein the HP and LP regions are the input and output, respectively, of a fluid compressor.

13. 13. The method of claim 8, wherein the ejector system further includes a second ejector, a drive fluid input of the second ejector connected to the ES drive fluid input, a suction input of the second ejector connected to the FE diffuser, and the diffuser of the second ejector in fluid communication with the ES fluid mixture output.

14. The method of any one of claims 8 to 13, further comprising controlling the head of the ejector with the controller.

15. Providing the booster-ejector system comprises: providing a first ejector housing including a first ejector drive fluid input, a first ejector suction input, a first ejector mixing chamber, and a first ejector diffuser; selecting a throat suitable for the operating conditions of said process; mounting the throat within the ejector housing, thereby providing the first ejector of the booster-ejector system; The method according to any one of claims 8 to 14, comprising:

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