Systems and methods for gas-driven compressor

Abstract

A gas driven compressor system includes a compressor body having first and second piston chambers and a shuttle valve chamber. The system has a low pressure outlet and a high pressure inlet in communication with the first piston chamber via a shuttle valve chamber, and a compressor inlet / outlet in communication with the second piston chamber. The shuttle valve moves within a cavity thereof between a first position and a second position. The piston has a first head movable by the pressurized input flow and a second head compressing the fluid in the second chamber. The piston selectively directs flow from the high pressure inlet to either side of the shuttle valve cavity based on piston position, thereby directing pressurized flow to either side of the first head. This arrangement powers the reciprocating movement of the piston.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 635,538, filed April 17, 2024, and U.S. Provisional Application No. 63 / 635,541, filed April 17, 2024, the entire contents of each of which are incorporated herein by reference. Background Art

[0003] Fluid systems, including pipes and containers, can store, transport, or otherwise distribute fluids, including pressurized gases and liquids. Fluid control systems, such as valves and regulators, can be used to regulate the flow of fluids within a fluid system. Summary of the Invention

[0004] According to one aspect of the present disclosure, a gas-driven compressor system may include a compressor body defining a first piston chamber, a second piston chamber, and a shuttle valve chamber. The system may include a low-pressure port in fluid communication with the first piston chamber via the shuttle valve chamber to discharge the first piston chamber. A high-pressure port may be in fluid communication with the first piston chamber via the shuttle valve chamber to provide a pressurized input flow to the first piston chamber. The system may include a compressor inlet in fluid communication with the second piston chamber and a compressor outlet in fluid communication with the second piston chamber. A shuttle valve may be movable within the shuttle valve chamber between a first position and a second position. The system may include a piston having a first head and a second head, the first head being movable within the first piston chamber by the pressurized input flow, and the second head being movable within the second piston chamber by movement of the first head within the first piston chamber to compress fluid within the second piston chamber. The piston may selectively fluidically couple a signal flow from the high-pressure port to a first side or a second side of the shuttle valve chamber, depending on the piston's position, to selectively direct the pressurized input flow to the first piston chamber on either the first side or the second side of the piston's first head, respectively, to power the piston's reciprocating motion.

[0005] In some examples, the piston may be configured to move in a first direction to draw fluid into the second piston chamber, and move in a second direction to compress the fluid within the second piston chamber.

[0006] In some examples, the piston may define a first groove and a second groove arranged to selectively fluidly couple a signal flow from the high pressure port to a first side or a second side of the shuttle valve cavity.

[0007] In some examples, the first groove can be aligned with the first shuttle valve signal line when the first head of the piston is in a first position in the first piston chamber, and the second groove can be aligned with the second shuttle valve signal line when the first head of the piston is in a second position in the first piston chamber.

[0008] In some examples, the first recess can be axially spaced from the second recess along the piston, and the high pressure port can be in communication with the piston along a first inlet signal line arranged to pressurize the first recess when the first head of the piston is at the first end of the first piston cavity and a second inlet signal line arranged to pressurize the second recess when the first head of the piston is at the second end of the first piston cavity.

[0009] In some examples, the first and second recesses can be included on the second head of the piston.

[0010] In some examples, the system can further include a lever coupling the first head to the second head.

[0011] In some examples, the first head of the piston can divide the first piston cavity into a first volume and a second volume. The shuttle valve in the first position can provide pressurized input flow to the first volume and vent the second volume to the low pressure port to move the piston in a first direction. The shuttle valve in the second position can provide pressurized input flow to the second volume and vent the first volume to the low pressure port to move the piston in a second, opposite direction.

[0012] According to another aspect of the disclosure, a method of compressing a fluid using a process gas driven compressor can include providing a high pressure port of a compressor body in communication with a first pressure, and providing a low pressure port of the compressor body in communication with a second pressure. The method can include reciprocally moving a first piston within a first piston cavity by moving a shuttle valve in response to a pressure differential between the high pressure port and the low pressure port, the movement of the shuttle valve selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston within the first piston cavity as a function of a position of a piston assembly including the first piston. The movement of the first piston can reciprocally move a second piston of the piston assembly in a second piston cavity to compress a fluid within the second piston cavity.

[0013] In some examples, the method can include aligning a first circumferential recess of the piston assembly with a first shuttle valve signal line when the piston assembly is in a first position to direct pressurized fluid from the high pressure port to a first side of the shuttle valve to move the shuttle valve from the first position to a second position, and aligning a second circumferential recess of the piston assembly with a second shuttle valve signal line when the piston assembly is in a second position to direct high pressure fluid to a second side of the shuttle valve to move the shuttle valve from the second position back to the first position.

[0014] In some examples, the method can include venting the compressed fluid from the second piston cavity through a compressor outlet port when the compressed fluid reaches a predetermined threshold pressure.

[0015] In some examples, the method can include selectively blocking, with the piston assembly, a fluid connection between the high pressure port and the shuttle valve signal line during reciprocation of the first and second pistons.

[0016] In some examples, drawing fluid into the second piston cavity can include drawing fluid into the second piston cavity through the inlet port and the first check valve during movement of the piston from the first position to the second position.

[0017] In some examples, the fluid compressed in the second piston cavity can be further compressed in a second stage of compression by reciprocation of the piston assembly.

[0018] In some examples, reciprocation of the piston assembly can direct compressed fluid from the second piston cavity to a third piston cavity for compression of the compressed fluid by reciprocation of the piston assembly.

[0019] According to yet another aspect of the disclosure, a gas-driven compressor system can include a high pressure port, a low pressure port, and a piston assembly. The piston assembly can include a first piston movable within a first piston cavity in response to a pressure differential between the high pressure port and the low pressure port, and a second piston movable within a second piston cavity by movement of the first piston to compress fluid within the second piston cavity. The system can include a shuttle valve movable between a first position and a second position in response to the pressure differential between the high pressure port and the low pressure port to cause reciprocation of the piston assembly by selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston depending on a position of the piston assembly.

[0020] In some examples, the system can include a lever mechanically coupled between the first piston and the second position to multiply a force applied by the first piston to the second piston.

[0021] In some examples, the shuttle valve can include extensions at opposite ends that extend into corresponding extensions of the shuttle valve cavity to selectively block flow from one or more signal lines into the shuttle valve cavity.

[0022] In some examples, the second piston can include a first bulkhead and a second bulkhead secured together by a piston rod.

[0023] In some examples, the first bulkhead can form a first chamber including an inlet port and an outlet port, and the second bulkhead can form a second chamber including a port to atmosphere. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a simplified diagram of an example of a process gas-driven compressor system having a piston and a shuttle valve arranged in a first position according to aspects of the disclosure.

[0025] Figure 2 yes Figure 1 Schematic diagram of a process gas driven compressor system with the piston in a first position and the shuttle valve arranged in a second position.

[0026] Figure 3 yes Figure 2 Schematic diagram of a process gas driven compressor system, wherein the piston is arranged in an intermediate position and the shuttle valve is arranged in a second position.

[0027] Figure 4 yes Figure 3 Schematic diagram of a process gas driven compressor system, wherein the piston is arranged in a second position and the shuttle valve is arranged in a second position.

[0028] Figure 5 yes Figure 4 Schematic diagram of a process gas driven compressor system, wherein the piston is arranged in the second position and the shuttle valve is arranged in the first position.

[0029] Figure 6 yes Figure 1 An isometric partial view of an exemplary embodiment of a process gas driven compressor system with a piston and a shuttle valve arranged in a first position.

[0030] Figure 7 yes Figure 1 An isometric partial view of an exemplary embodiment of a process gas driven compressor system with a piston in a first position and a shuttle valve arranged in a second position.

[0031] Figure 8 yes Figure 1 An isometric partial view of an exemplary embodiment of a process gas driven compressor system with the piston arranged in an intermediate position and the shuttle valve arranged in a second position.

[0032] Figure 9 yes Figure 1 An isometric partial view of an exemplary embodiment of a process gas driven compressor system with the piston arranged in a second position and the shuttle valve arranged in a second position.

[0033] Figure 10 yes Figure 1 An isometric partial view of an exemplary embodiment of a process gas driven compressor system with the piston arranged in a second position and the shuttle valve arranged in a first position.

[0034] Figure 11 is a simplified diagram of another example of a process gas driven compressor system according to aspects of the present disclosure.

[0035] Figure 12 is a diagram of another example of a process gas driven compressor system according to aspects of the present disclosure.

[0036] Figure 13 is a diagram of another example of a process gas driven compressor system according to aspects of the present disclosure. Figure 12 is an isometric view of a piston of the process gas driven compressor system of

[0037] Figure 14 is an isometric view of a piston of the process gas driven compressor system of Figure 13

[0038] Figure 15 is a cross-sectional isometric view of a piston of the process gas driven compressor system of Figure 13

[0039] Figure 16 is a diagram of another example of a process gas driven compressor system according to aspects of the present disclosure. Figure 13 Figure 12

[0040] Figure 17 is a diagram of another example of a process gas driven compressor system according to aspects of the present disclosure. Figure 12 DETAILED DESCRIPTION The following discussion is presented to enable a person skilled in the art to make and use embodiments of the application. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the principles described herein can be applied to other embodiments and applications without departing from the scope of the embodiments of the present application. Thus, the present embodiments are not intended to be limited to the

[0041] The following detailed description will be read with reference to the accompanying drawings, in which like elements in different drawings have the same reference numbers. The drawings depict only selected embodiments and are not intended to limit the scope of the embodiments of the present application. One skilled in the art will recognize that the examples provided herein have a number of useful alternatives and fall within the scope of embodiments of the present application.

[0042] The following detailed description will be read with reference to the accompanying drawings, in which like elements in different drawings have the same reference numbers. The drawings depict only selected embodiments and are not intended to limit the scope of the embodiments of the present application. One skilled in the art will recognize that the examples provided herein have a number of useful alternatives and fall within the scope of embodiments of the present application.

[0043] ​​​​Before any embodiments of the application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the following drawings. The application is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and not of limitation. The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms "mounted," "connected," "supported," and "coupled" and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, "connected" and "coupled" are not restricted to physical or mechanical connections or couplings.

[0044] As briefly described above, some natural gas products, such as valves and electronic regulators, use low pressure gas to operate. In use, some applications of valves and regulators require venting to atmosphere (e.g., auto reset spring open regulators). With conventional valves and regulators, one challenge is that the low pressure gas required is at a lower pressure than the lowest pressure in the system and cannot be reinjected into the pipeline. One approach is to use low pressure compressed air to operate these products. This requires a certain amount of gas compression infrastructure. In remote areas, this can be a challenge. Alternatively, the process medium can be reduced to an appropriate level and then discharged once used. Discharging process medium to atmosphere can be disadvantageous for various reasons, including negative environmental factors.

[0045] Aspects of the present disclosure can address these and other disadvantages of conventional operation of valves and regulators. For example, some implementations of the present disclosure provide a process gas driven compressor. The compressor can re-pressurize low pressure process gas and inject it back into a system (e.g., a pipeline) after use. In particular, examples of the present disclosure can provide a compressor that uses process medium to drive a piston of the compressor and produce pressurized fluid that can be reinjected back into a system. For example, the compressor can pressurize process fluid by moving a piston linearly back and forth to compress fluid within a piston cylinder. In some examples, incorporating a second stage in the compression system can increase output pressure as compared to a single stage compression system.

[0046] In some examples, a compressor system includes a compressor body having first and second piston cavities that receive portions of a piston. A head of the piston divides the first cavity into first and second volumes. The system includes a high pressure inlet and a low pressure inlet connected to respective pressure lines, where a delivery line directs pressurized fluid to either the first or second volume based on a shuttle valve orientation, and correspondingly vents the other volume to the low pressure inlet. In some examples, a shuttle valve controls the fluid flow direction. The shuttle valve is moved via high pressure fluid supplied through a shuttle valve signal line, which directs fluid to either side of the shuttle valve to control the shuttle valve movement depending on the current state of the compressor.

[0047] In some examples, the second piston cavity includes an inlet port having a first check valve that allows one-way fluid inflow, and an outlet port having a second check valve that allows one-way fluid outflow. This arrangement allows for fluid compression as the piston moves.

[0048] In some examples, during use, the piston moves through a series of stages. For example, in a first stage, the piston and shuttle valve are in a first position. High pressure fluid enters the first volume through a first delivery line, while the second volume is vented to lower pressure through a second delivery line. When the piston is in the first position, a first circumferential groove in the piston shaft (or other feature) is aligned with the high pressure line and a first shuttle valve signal line, allowing high pressure fluid to flow to a first side of the shuttle valve to move the shuttle valve.

[0049] In a second stage, the shuttle valve moves to a second position (e.g., by pressure as described above), redirecting high pressure fluid to the second volume and venting the first volume to lower pressure. This initiates piston motion (e.g., a third stage) that begins to draw fluid into the second piston cavity through the inlet port.

[0050] In a fourth stage, a second circumferential groove of the piston shaft (or other feature) is aligned with the high pressure line and a second shuttle valve signal line, directing high pressure fluid to a second side of the shuttle valve to move the shuttle valve toward the first position.

[0051] In a fifth stage, the shuttle valve returns to the first position, redirecting high pressure fluid to the first volume and venting the second volume to lower pressure. This causes the piston to move toward the first position, compressing fluid in the second piston cavity until it reaches sufficient pressure to exit through the second check valve and outlet port.

[0052] In some examples, the system can utilize a lever to connect the first piston to the second piston in order to provide a mechanical advantage to produce a higher output pressure from a lower input pressure difference. In other examples, other systems for mechanical advantage can also or instead be used (e.g., providing a larger acting surface area on the first piston than on the second piston, etc.).

[0053] In some examples, the compressor system can be a two-stage compressor system. For example, movement of the piston in a first direction can cause a first stage of compression (e.g., in the second piston cavity, as described above). This first stage of compressed fluid can be directed to another piston cavity (e.g., similar to the second piston cavity, as described above) and then further compressed by movement of the piston (e.g., in a second direction). In some examples, the shuttle valve can include an extension having a radial passage to control fluid flow while preventing pressure relief.

[0054] Figures 1-5 An example of a compressor system 100 (e.g., a process fluid driven compressor system) is shown. The compressor system 100 can be in the form of a process fluid driven compressor including a compressor body 102 defining a first piston cavity 126 and a second piston cavity 155. In some examples, the first piston cavity 126 and the second piston cavity 155 can each receive a portion of a piston 108 (e.g., a main piston). For example, a first head 145 of the piston 108 can translate within the first piston cavity 126, while a second head (e.g., a narrower shaft) 165 of the piston can translate within the second piston cavity 155. In some examples, the head 145 of the piston 108 can have a larger diameter than the shaft 165 of the piston 108, or other differently sized pistons or piston heads can be provided. Correspondingly, the first piston cavity 126 can have a larger diameter than the second piston cavity 155.

[0055] In some examples, the head 145 of the piston 108 can divide the first piston cavity 126 into a first volume 125 and a second volume 135. Correspondingly, to actuate (e.g., move) the piston 108 within the first piston cavity 126 and the second piston cavity 155, a varying pressure can be applied to the head 145 of the piston 108 (e.g., via a high pressure fluid flow into the first piston cavity or the second piston cavity, and correspondingly venting the other piston cavity). In some examples, to provide high pressure / low pressure fluid to the system 100, the body 102 can include a high pressure port (e.g., inlet) 104 and a low pressure port (e.g., inlet) 106. In some examples, one or more high pressure lines 120 (or other inlet flow paths) can be in communication with the high pressure inlet 104. Correspondingly, one or more low pressure lines 124 (or other inlet flow paths) can be in communication with the low pressure inlet 106.

[0056] In some examples, depending on the orientation of the shuttle valve, fluid from the high pressure line 120 can enter the first volume 125 or the second volume 135 via the first transfer line 114 or the second transfer line 116, and the same is true for fluid discharge from the volumes 125, 135 to the low pressure line 124. Thus, in some examples, the direction of travel of the piston 108 can be controlled (e.g., via alternating high pressure fluid flow into the first volume 125 or the second volume 135) based on the orientation of the shuttle valve.

[0057] In some examples, in addition to the piston 108, the system 100 can include a shuttle valve 110, which can be housed within a shuttle valve cavity 132 separate from the first piston cavity 126 and the second piston cavity 155. In some examples, the shuttle valve 110 can be moved within the shuttle valve cavity 132 via high pressure fluid from the high pressure inlet 104. For example, the shuttle valve cavity 132 can receive high pressure fluid from the high pressure inlet 104 via one or more shuttle valve signal lines 134. For example, a first shuttle valve signal line 134 can apply a high pressure fluid signal to a first side of the shuttle valve 110 (e.g., to move the shuttle valve 110 in a first direction), while a second shuttle valve signal line 136 can apply a high pressure fluid signal to a second side of the shuttle valve 110 (e.g., to move the shuttle valve 110 in an opposite, second direction). As described in further detail below, depending on the position of the shuttle valve 110, ridges and grooves (or other features) on the shuttle valve 110 can cause selective pressurization and discharge of the first piston cavity 126 to drive reciprocation of the piston 108.

[0058] In some examples, to facilitate fluid flow into and out of the second piston cavity 155, the compressor system 100 can include an inlet port 148 (or other compressor inlet) and an outlet port 115 (or other compressor outlet). In some examples, the inlet port 148 can include a first check valve 140 (e.g., a suction valve) that can allow one-way fluid flow into the second piston cavity 155. Correspondingly, the outlet port 115 can include a second check valve 142 (e.g., a discharge valve) that can allow one-way fluid flow out of the second piston cavity 155. For example, the inlet port 148 and the corresponding check valve 140 can allow low pressure fluid flow into the second piston cavity 155 during movement of the piston 108 in a first direction. Correspondingly, the outlet port 115 and the corresponding check valve 142 can allow high pressure fluid flow out of the second piston cavity 155 when fluid is compressed due to movement of the piston 108 in an opposite, second direction. Generally, the check valve 142 can be configured to allow discharge of compressed fluid (e.g., to the outlet port 115) once the compressed fluid reaches a predetermined threshold pressure.

[0059] With continued reference to Figures 1-5An example process using the compressor system 100 for compressing a fluid (e.g., a process fluid from a pipeline, air, etc.) will be described. For example, Figure 1 A first stage of the fluid compression process is shown. In the first stage, each of the piston 108 and shuttle valve 110 is disposed in a respective first position 175, 185. That is, with respect to the orientation shown, each of the piston 108 and shuttle valve 110 is disposed on the right side of their respective cavities 126, 132. In some examples, to bring the piston 108 to the first position 175, the high pressure inlet 104 can supply high pressure fluid from the high pressure line 120 to the first volume 125 through the first transfer line 114. Correspondingly, the low pressure inlet 106 can vent the second volume 135 to the low pressure discharge via the low pressure line 124 and the second transfer line 116. Figure 1

[0060] In some examples, due to the orientation of the shuttle valve 110 in the first position 185, the first transfer line 114 is configured as a high pressure line (e.g., fluidically connected to the high pressure line 120). However, when the shuttle valve 110 is moved to the second position, the first transfer line 114 can transition to a low pressure line (e.g., fluidically connected to the low pressure line 124).

[0061] Generally, features on the piston 108 or body 102 can cooperate to selectively direct a signal pressure to opposite sides of the shuttle valve 110 depending on the position of the piston 108. In some examples, when the piston 108 is in the first position 175, a first circumferential groove 152 formed in the shaft 165 of the piston 108 can align with the high pressure line 120 and the first shuttle valve signal line 134. Accordingly, high pressure fluid from the high pressure line 120 can flow through the first shuttle valve signal line 134 and to the first side of the shuttle valve 110. Correspondingly, the shuttle valve 110 can begin to actuate within the shuttle valve cavity 132 in the direction shown by arrow 167.

[0062] Turning now to Figure 2 , a second stage of the fluid compression process is shown. In the second stage, the piston 108 remains in the first position 175 while the shuttle valve 110 has moved to the second position 187. With the shuttle valve 110 in the second position 187, high pressure fluid from the high pressure line 120 is now in fluid communication with the second volume 135 via the second transfer line 116. Correspondingly, the low pressure inlet 106 can vent the first volume 125 to the low pressure discharge via the low pressure line 124 and the first transfer line 114. As a result, the piston 108 can begin to move in the direction shown by arrow 169 (e.g., see Figure 3 ​), which can begin to draw fluid into the second piston cavity 155 via the inlet port 148 (e.g., through the first check valve 140). Moreover, the fluid connection between the high pressure line 120 and the shuttle valve signal lines 134, 136 can be blocked by the shaft 165 of the piston 108 during movement of the piston in the direction indicated by arrow 169.

[0063] As shown in FIG. 1, the piston 108 can be in a first position 175 at a first stage of the fluid compression process. At the first stage, the high pressure inlet 104 can supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can begin to move in the direction indicated by arrow 191 (e.g., toward the second position 177, see, e.g., FIG. 2). Figure 4 As shown in FIG. 2, the piston 108 can be in the second position 177 at a second stage of the fluid compression process. At the second stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the third position 179, see, e.g., FIG. 3). As shown in FIG. 3, the piston 108 can be in a third position 179 at a third stage of the fluid compression process. At the third stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the fourth position 181, see, e.g., FIG. 4).

[0064] As shown in FIG. 4, the piston 108 can be in a fourth position 181 at a fourth stage of the fluid compression process. At the fourth stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the fifth position 183, see, e.g., FIG. 5). Figure 5 As shown in FIG. 5, the piston 108 can be in a fifth position 183 at a fifth stage of the fluid compression process. At the fifth stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the sixth position 185, see, e.g., FIG. 6). Figure 1 As shown in FIG. 6, the piston 108 can be in a sixth position 185 at a sixth stage of the fluid compression process. At the sixth stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the seventh position 187, see, e.g., FIG. 7). As shown in FIG. 7, the piston 108 can be in a seventh position 187 at a seventh stage of the fluid compression process. At the seventh stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the eighth position 189, see, e.g., FIG. 8).

[0065] As shown in FIG. 8, the piston 108 can be in an eighth position 189 at an eighth stage of the fluid compression process. At the eighth stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the ninth position 191, see, e.g., FIG. 9). As shown in FIG. 9, the piston 108 can be in a ninth position 191 at a ninth stage of the fluid compression process. At the ninth stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the tenth position 193, see, e.g., FIG. 10).

[0066] As shown in FIG. 10, the piston 108 can be in a tenth position 193 at a tenth stage of the fluid compression process. At the tenth stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the eleventh position 195, see, e.g., FIG. 11). Figures 6-10 As shown in FIG. 11, the piston 108 can be in an eleventh position 195 at an eleventh stage of the fluid compression process. At the eleventh stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the twelfth position 197, see, e.g., FIG. 12). Figures 1-5 As shown in FIG. 12, the piston 108 can be in a twelfth position 197 at a twelfth stage of the fluid compression process. At the twelfth stage, the high pressure inlet 104 can continue to supply high pressure fluid from the high pressure line 120 to the first volume 125 via the first transfer line 114. Correspondingly, the low pressure inlet 106 can continue to vent the second volume 135 to the low pressure exhaust via the low pressure line 124 and the second transfer line 116 to the second volume 135. As a result, the piston 108 can continue to move in the direction indicated by arrow 191 (e.g., toward the thirteenth position 199, see, e.g., FIG. 13). Figures 1-5The system 600 shares certain number of components with the previously shown and described examples (e.g., the system 100) and operates in a manner similar to the previously shown and described examples. For the sake of brevity, these shared features will not be described in detail again. Rather, unless otherwise noted, the previous discussion of commonly named or numbered features also applies to the example configuration of the system 600.

[0067] Similarly, Figure 1 , Figure 6 An example of the system 600 is shown in a first stage, where the piston 108 is in the first position 175 and the shuttle valve 110 is in the first position 185. Similarly, Figure 2 , Figure 7 An example of the system 600 is shown in a second stage, where the piston 108 is in the first position 175 and the shuttle valve 110 is in the second position 187. Similarly, Figure 3 , Figure 8 An example of the system 600 is shown, where the piston 108 is moving between the first position 175 and the second position 177 (e.g., by drawing fluid into the second piston chamber 155 through the inlet port 148) and the shuttle valve 110 is in the second position 187. Similarly to Figure 4 , Figure 9 An example of the system 600 is shown, where the piston 108 is in the second position 177 and the shuttle valve 110 is in the second position 187. Similarly, Figure 5 , Figure 10 An example of the system 600 is shown, where the piston 108 is in the second position 177 and the shuttle valve 110 is in the first position 185. Correspondingly, as described above, the piston 108 can begin to move between the second position 177 and the first position 175. As a result, the fluid within the second piston chamber 155 can be compressed, which can pressurize the fluid. In some examples, once the fluid reaches a predetermined pressure, the fluid can flow out of the second check valve 142 and out of the outlet port 115.

[0068] Figure 11 Another example of a process gas driven compressor system 1100 is shown. As will be appreciated, the system 1100 shares certain number of components with the previously shown and described examples (e.g., the system 100) and operates in a manner similar to the previously shown and described examples. For the sake of brevity, these shared features will not be described in detail again. Rather, unless otherwise noted, the previous discussion of commonly named or numbered features also applies to the example configuration of the system 1100.

[0069] In some examples, the system 1100 can be particularly suitable for applications in which only a small pressure differential is available (e.g., where no control valve is available). For example, to create a relatively small pressure drop, a first Pitot tube (or similar) can be oriented toward (e.g., facing upstream) the fluid flow in the pipeline, while a second Pitot tube (or similar) can be oriented away from (e.g., facing downstream) the fluid flow in the pipeline. As a result, a small pressure differential can exist between the first and second Pitot tubes, which can be combined with a mechanical advantage (e.g., a lever) in order to pressurize a fluid (e.g., atmospheric, process fluid, etc.).

[0070] In some examples, similar to the system 100, the system 1100 can create movement in the piston 108 based on the position of the shuttle valve 110. For example, when the high pressure fluid is directed into the first volume 125 and the second volume 135 is vented to low pressure, the piston 108 can move in the direction shown by the arrow 1140. In some examples, the piston 108 can be mechanically connected to a second piston 1145 via a lever 1125. In some examples, the second piston 1145 can include a first partition 1105 and a second partition 1110 that are secured together via a second piston rod 1135. Further, in some examples, the lever 1125 can be connected at a first end to a first piston rod 1130 that extends from the piston 108, and at a second end to the second piston rod 1135. Accordingly, when the piston 108 moves in the direction shown by the arrow 1140, the second piston 1145 can move in the direction shown by the arrow 1150. As a result, fluid can be expelled from a second chamber 1115 formed by the second partition 1110 (e.g., out of a port 1120 that is in fluid communication with atmospheric). Correspondingly, fluid can be drawn into a first chamber 1155 formed by the first partition 1105 through an inlet port 148 (e.g., including a first check valve 140).

[0071] In some examples, the shuttle valve 110 can then switch positions (e.g., from the first position 185 to the second position 187), which can direct the high pressure fluid into the second volume 135 and vent the first volume 125 to low pressure. As a result, the piston 108 can move in the direction shown by the arrow 1150. In some examples, when the piston 108 moves in the direction shown by the arrow 1150, the second piston 1145 can move in the direction shown by the arrow 1140. As a result, fluid can be drawn into the second chamber 1115 (e.g., from atmospheric via the port 1120). Correspondingly, fluid can be pressurized within the first chamber 1155. In some examples, once the fluid within the first chamber 1155 reaches a predetermined pressure, the pressurized fluid can flow out of an outlet port 115 (e.g., including a second check valve 142).

[0072] It should be appreciated that the system 1100 described above can utilize a relatively low pressure differential and the mechanical advantage provided by the lever 1125 to pressurize the fluid. In one particular example, a pressure drop of about 3 PSI across the piston 108 can result in a pressure of about 100 PSI at the outlet 115.

[0073] Figures 12-17 Another example of a process gas driven compressor system 200 is shown. In some examples, the system 200 can function similarly to the system 100. However, the system 200 can be in the form of a two-stage compressor system. In some examples, the system 200 can include a compressor body 202 having a generally irregular geometry. It should be appreciated that other body geometries are possible, such that the compressor body 202 can be optimized and reshaped to a regular or irregular geometry depending on size, pressurization, and other system requirements. Further, the compressor body 202 can be formed from a variety of materials and manufacturing methods, including additive manufacturing (e.g., 3D printing), which can be used to further optimize the geometry of the body 202.

[0074] In some examples, the compressor body 202 can include a high pressure inlet 204, a low pressure inlet 206, a first piston cavity 210, and a shuttle valve cavity 212. The high pressure inlet 204 is in communication with a high pressure line 216, and the low pressure inlet 206 is in communication with a low pressure line 218. In some examples, one or more shuttle valve signal lines (e.g., a first shuttle valve signal line 222 and a second shuttle valve signal line 225) are used to transfer pressure from the first piston cavity 210 to the shuttle valve cavity 212 during operation. As will be described below, first and second transfer conduits 224, 226 can transfer high pressure fluid and low pressure fluid from the high pressure inlet 204 and the low pressure inlet 206 depending on the position of a piston 230 in the piston cavity 210 and the position of a shuttle valve 254 in the shuttle valve cavity 212.

[0075] Figures 13-15 An example of a piston 230 that can be included in the compressor system 200 is shown. In some examples, the piston 230 includes a piston body 232 having a first piston rod 234 and a second piston rod 238 extending away from opposite sides of the piston body 232. In some examples, because the system 200 is a two-stage compressor system, the first rod 234 can include a first pressurization surface 236, and the second rod 238 can include a second pressurization surface 240. The pressurization surfaces 236, 240 can be disposed on opposite axial ends of the piston body 232 and generally provide first and second compression stages, respectively, within the compressor system 200. The piston body 232 also includes first and second piston heads 242, 244 separated by a piston core 246.

[0076] In some examples, the first piston head 242 includes a first circumferential groove 243, and the second piston head 244 includes a second circumferential groove 245. In some examples, each of the first and second heads 242, 244 includes a respective first and second communication ports 248, 250 extending therethrough. In some examples, the first communication port 248 can extend from an outer surface of the second head 244, through the core 246, and into the first circumferential groove 243 of the first head 242. Correspondingly, the second communication port 250 can extend from an outer surface of the first head 242, through the core 246, and into the second circumferential groove 245 of the second head 244. In some examples, the ports 248, 250 can allow fluid communication between the piston chamber 210 and the shuttle valve chamber 212 via the shuttle valve signal lines 222, 225.

[0077] During use of system 200, piston 230 can move axially back and forth within piston chamber 210 to pressurize the fluid. Typically, in a two-stage system, the discharge pressure from the first stage enters the inlet of the second stage, thereby increasing the outlet pressure. Thus, compressor system 200 can be used to reinject relatively high-pressure fluid into a fluid system without having to exhaust residual fluid into the atmosphere or another container. For example, first pressurization surface 236 can pressurize fluid within compressor body 202 in first compression chamber 305 at the first compression stage. The pressurized fluid can then travel via pressure passage 260 to second compression chamber 310, where second pressurization surface 240 can further increase the pressure at the second compression stage. Following pressurization of the fluid within second compression chamber 310, the fluid can exit outlet port 315 (e.g., once at a predetermined pressure set by a check valve, etc.).

[0078] In use, the piston 230 can be on the right side of the first head 242 via the first transfer line 224 or on the left side of the second head 244 via the second transfer line 226 (relative to the left side of the second head 244). Figure 16 In addition, the second communication port 250 (see Figure 15 ) can transfer pressure applied to the right side of first head portion 242 to second circumferential groove 245. Thus, when piston 230 has moved sufficiently leftward under pressure on first head portion 242 to align second circumferential groove 245 with shuttle valve signal line 222, the higher pressure applied to the right side of first head portion 242 can be transferred to the left side of shuttle valve chamber 212. Consequently, this higher pressure can cause shuttle valve 254 to move rightward (in the direction shown) based on the position of piston 230. Moving shuttle valve 254 to the right then directs the higher pressure to the left side of second head portion 244 to drive piston 230 back to the right (as described above).

[0079] In this regard, similarly, the first communication port 248 (see Figure 15 ) can communicate pressure applied at the left surface of the second head 244 to the first circumferential groove 243. When the first circumferential groove 243 is aligned with the shuttle valve signal line 225 (see also Figure 17 ), the pressure applied at the left surface of the second head 244 can be communicated to the shuttle valve cavity 212 to move the shuttle valve 254 in an opposite direction, and with reference to the foregoing discussion, to continue reciprocation of the piston 230.

[0080] In some examples, based on the position of the shuttle valve 254 (e.g., as described above), high pressure fluid from the high pressure inlet 204 can move the piston 230 to the right (reference Figure 16 ), which can compress fluid within the first compression chamber 305, and then expel the compressed fluid from the first compression chamber 305. Similarly, based on the position of the shuttle valve 254, high pressure fluid from the high pressure inlet 204 can also move the piston 230 to the left (reference Figure 16 ), which can compress fluid (e.g., received from the first compression chamber 305) within the second compression chamber 310 and push the further compressed fluid out of the outlet 315. Correspondingly, movement of the piston 230 to the right can push fluid from the first compression chamber 305 to the second compression chamber 310, and movement of the piston 230 to the left can push pressurized fluid out of the second compression chamber 310 while also drawing new fluid into the first compression chamber 305 via the inlet 320.

[0081] Referring to Figure 17 , in some examples, the compressor body 202 can include auxiliary chambers 268 in communication with the shuttle valve cavity 212. Relatedly, in some examples, a shuttle valve, such as the shuttle valve 254, can include extensions 270 that extend into the auxiliary chambers 268 to block flow from the high pressure inlet 204. As a result, the extensions 270 can mitigate the risk of pressure bleed into the system. In some examples, to facilitate movement of the shuttle valve (e.g., due to flow of fluid), the extensions 270 can each include a radial passage 272 that can fluidly couple the auxiliary chamber 268 to the shuttle valve cavity 212. However, in some examples, when the shuttle valve 254 is placed in the first position 185 or the second position 187 (e.g., as shown in Figure 17 ), the radial passages 272 can be blocked.

[0082] Advantages of the present disclosure provide a fluid pressurization system that uses process fluid that can be re-injected into a pressurized fluid line without needing to be vented to atmosphere. Accordingly, examples of the disclosed technology can provide improvements over conventional systems and methods for pressurizing and conserving fluid within a fluid system, such as systems having parallel regulators that can need to be switched during maintenance or other use, where it can be useful to re-inject residual fluid into the system rather than venting it to atmosphere.

[0083] In some embodiments, the devices or systems disclosed herein can be utilized, manufactured, or installed using methods embodying aspects of the present disclosure. Correspondingly, any description herein of particular features, capabilities, or intended purposes of a device or system is generally intended to include disclosure of methods of using such device for the intended purposes, methods of otherwise implementing such capabilities, methods of manufacturing the relevant components of such device or system (or device or system as a whole), and methods of installing the disclosed (or otherwise known) components to support such purposes or capabilities. Similarly, unless otherwise indicated or limited, any discussion herein of methods of manufacturing or using a particular device or system (including installation of the device or system) is intended to inherently include disclosure of the utilized features and implemented capabilities of such device or system as embodiments of the present disclosure.

[0084] Further examples

[0085] Example 1. A gas-driven compressor system comprising: a compressor body defining a first piston cavity, a second piston cavity, and a shuttle valve cavity; a low pressure port in fluid communication with the first piston cavity via the shuttle valve cavity to vent the first piston cavity; a high pressure port in fluid communication with the first piston cavity via the shuttle valve cavity to provide a pressurized input flow to the first piston cavity; a compressor inlet in fluid communication with the second piston cavity; a compressor outlet in fluid communication with the second piston cavity; a shuttle valve movable within the shuttle valve cavity between a first position and a second position; and a piston having a first head and a second head, the first head movable within the first piston cavity by the pressurized input flow, the second head movable within the second piston cavity by movement of the first head within the first piston cavity to compress a fluid within the second piston cavity; the piston selectively fluidically couples a signal flow from the high pressure port to a first side or a second side of the shuttle valve cavity according to a position of the piston to selectively direct the pressurized input flow on a first side or a second side of the first head of the piston to the first piston cavity, respectively, to power reciprocation of the piston.

[0086] Example 2. The gas-driven compressor system of example 1, wherein the piston is configured to move in a first direction to draw fluid into the second piston cavity and in a second direction to compress fluid within the second piston cavity.

[0087] Example 3. The gas-driven compressor system of any one of examples 1-2, wherein the piston defines a first groove and a second groove arranged to selectively fluidly couple the signal stream from the high pressure port to the first side or the second side of the shuttle valve cavity.

[0088] Example 4. The gas-driven compressor system of example 3, wherein the first groove is aligned with the first shuttle valve signal line when the first head of the piston is in a first position in the first piston cavity, and wherein the second groove is aligned with the second shuttle valve signal line when the first head of the piston is in a second position in the first piston cavity.

[0089] Example 5. The gas-driven compressor system of any one of examples 3-4, wherein the first groove and the second groove are axially spaced along the piston, and the high pressure port is in communication with the piston along a first inlet signal line arranged to pressurize the first groove when the first head of the piston is at a first end of the first piston cavity, and a second inlet signal line arranged to pressurize the second groove when the first head of the piston is at a second end of the first piston cavity.

[0090] Example 6. The gas-driven compressor system of any one of examples 3-5, wherein the first groove and second groove are included on the second head of the piston.

[0091] Example 7. The gas-driven compressor system of any one of examples 1-6, further comprising: a lever coupling the first head to the second head.

[0092] Example 8. The gas-driven compressor system of any one of examples 1-7, wherein the first head of the piston divides the first piston cavity into a first volume and a second volume; wherein a shuttle valve in the first position causes the pressurized input stream to the first volume and causes the second volume to vent to the low pressure port to move the piston in a first direction; and wherein a shuttle valve in the second position provides the pressurized input stream to the second volume and causes the first volume to vent to the low pressure port to move the piston in a second, opposite direction.

[0093] Example 9. A method of compressing a fluid using a process gas driven compressor, comprising: providing a high pressure port of a compressor body in communication with a first pressure; providing a low pressure port of the compressor body in communication with a second pressure; and moving a first piston in a reciprocating motion within a first piston cavity by moving a shuttle valve in response to a pressure differential between the high pressure port and the low pressure port, the movement of the shuttle valve selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston within the first piston cavity as a function of a position of a piston assembly comprising the first piston; the movement of the first piston moving a second piston of the piston assembly in a reciprocating motion in a second piston cavity to compress a fluid within the second piston cavity.

[0094] Example 10. The method of example 9, further comprising: aligning a first circumferential groove of the piston assembly with a first shuttle valve signal line to direct pressurized fluid from the high pressure port to a first side of the shuttle valve to move the shuttle valve from a first position to a second position when the piston assembly is in the first position; and aligning a second circumferential groove of the piston assembly with a second shuttle valve signal line to direct high pressure fluid to a second side of the shuttle valve to move the shuttle valve from the second position back to the first position when the piston assembly is in the second position.

[0095] Example 11. The method of any one of examples 9-10, further comprising: expelling the compressed fluid from the second piston cavity through a compressor outlet port when the compressed fluid reaches a predetermined threshold pressure.

[0096] Example 12. The method of any one of examples 9-11, further comprising: selectively blocking fluid connection between the high pressure port and the shuttle valve signal line with the piston assembly during the reciprocating motion of the first piston and the second piston.

[0097] Example 13. The method of any one of examples 9-12, wherein drawing fluid into the second piston cavity comprises: drawing fluid into the second piston cavity through the inlet port and a first check valve during movement of the piston from the first position to the second position.

[0098] Example 14. The method of any one of examples 9-13, wherein the fluid compressed in the second piston cavity is further compressed in a second stage of compression by the reciprocating motion of the piston assembly.

[0099] Example 15. The method of example 14, wherein the reciprocating motion of the piston assembly directs the compressed fluid from the second piston cavity to a third piston cavity to compress the compressed fluid by the reciprocating motion of the piston assembly.

[0100] Example 16. A gas-driven compressor system, comprising: a high pressure port; a low pressure port; a piston assembly comprising a first piston and a second piston, the first piston movable within a first piston cavity in response to a pressure differential between the high pressure port and the low pressure port, the second piston movable within a second piston cavity by movement of the first piston to compress a fluid within the second piston cavity; and a shuttle valve movable between a first position and a second position in response to the pressure differential between the high pressure port and the low pressure port to cause reciprocating motion of the piston assembly by selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston depending on a position of the piston assembly.

[0101] Example 17. The gas-driven compressor system of example 16, further comprising: a lever mechanically coupled between the first piston and the second position to multiply a force applied by the first piston to the second piston.

[0102] Example 18. The gas-driven compressor system of any of examples 16-17, wherein the shuttle valve comprises extensions at opposite ends that extend into corresponding extensions of a shuttle valve cavity to selectively block flow from one or more signal lines into the shuttle valve cavity.

[0103] Example 19. The gas-driven compressor system of any of examples 16-18, wherein the second piston comprises a first bulkhead and a second bulkhead secured together by a piston rod.

[0104] Example 20. The gas-driven compressor system of example 19, wherein the first bulkhead forms a first chamber comprising an inlet port and an outlet port, and wherein the second bulkhead forms a second chamber comprising a port to atmosphere.

[0105] Unless otherwise stated or limited, the terms “about” and “approximately” as used herein in reference to a reference value mean a variation of ± 15% or less from the reference value, inclusive of the endpoints of the range. Similarly, as used herein in reference to a reference value, the term “substantially” means a variation of ± 5% or less from the reference value, inclusive of the endpoints of the range.

[0106] Also, as used herein in reference to a clamping system, unless otherwise specified or limited, “axial” is used to refer to the clamping direction, and “radial” is used to refer to a direction perpendicular to the clamping direction. Thus, for example, in a system that applies a vertical clamping force to hold a heater assembly and a clamp subassembly together, the axial direction is parallel to the vertical direction, and the radial direction is parallel to the horizontal direction.

[0107] As also used herein, unless otherwise limited or defined, "or" indicates a nonexclusive disjunction of the components or operations that can exist in any of a variety of combinations, rather than an exclusive disjunction of the components that exist only as alternatives to one another. For example, a list of "A, B, or C" indicates the following options: A; B; C; A and B; A and C; B and C; and A, B, and C. Correspondingly, the term "or" as used herein is intended to mean an exclusive disjunction only if the exclusive term "either" is present alongside it (e.g., "either A, B, or C"). For example, a list of "one of A, B, or C" indicates the following options: A, but not B and C; B, but not A and C; and C, but not A and B. The presence of "one or more of" (and variations thereof) and an inclusion of "or" to separate lists of enumerated elements indicates options of one or more of any or all of the listed elements. For example, the phrases "one or more of A, B, or C" and "at least one of A, B, or C" indicate the following options: one or more A; one or more B; one or more C; one or more A and one or more B; one or more B and one or more C; one or more A and one or more C; and one or more A, one or more B, and one or more C. Similarly, the presence of "plurality of" (and variations thereof) and an inclusion of "or" to separate lists of enumerated elements indicates options of a plurality of instances of any or all of the listed elements. For example, the phrases "plurality of A, B, or C" and "two or more of A, B, or C" indicate the following options: A and B; B and C; A and C; and A, B, and C.

[0108] As also used herein, unless otherwise limited or defined, directional terms are used to facilitate discussion of particular drawings or examples, or to indicate spatial relationships with respect to particular other components or context, but are not intended to indicate absolute orientation. For example, references to downward, forward, or other directions, or references to top, rear, or other locations (or features) can be used in discussing aspects of particular examples or drawings, but do not necessarily require similar orientations or geometries in all installations or configurations.

[0109] As also used herein, unless otherwise limited or defined, "configured to" indicates that a component, system, or module is specifically adapted to the associated function. Thus, for example, a ZZ configured to YY is specifically adapted to YY, rather than merely being capable of such in general.

[0110] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A gas-driven compressor system, comprising: a compressor body defining a first piston cavity, a second piston cavity, and a shuttle valve cavity; a low pressure port in fluid communication with the first piston cavity via the shuttle valve cavity to vent the first piston cavity; a high pressure port in fluid communication with the first piston cavity via the shuttle valve cavity to provide a pressurized input stream to the first piston cavity; a compressor inlet in fluid communication with the second piston cavity; a compressor outlet in fluid communication with the second piston cavity; a shuttle valve movable within the shuttle valve cavity between a first position and a second position; and a piston having: a first head movable within the first piston cavity by the pressurized input stream; and a second head movable within the second piston cavity by movement of the first head within the first piston cavity to compress a fluid within the second piston cavity; the piston selectively fluidically coupling a signal stream from the high pressure port to a first side or a second side of the shuttle valve cavity depending on a position of the piston to selectively direct the pressurized input stream to a first side or a second side of the first piston cavity on the first head of the piston to power reciprocation of the piston.

2. The gas-driven compressor system of claim 1, wherein the piston is configured to move in a first direction to draw fluid into the second piston cavity and in a second direction to compress the fluid within the second piston cavity.

3. The gas-driven compressor system of claim 1, wherein the piston defines a first groove and a second groove arranged to selectively fluidically couple the signal stream from the high pressure port to the first side or the second side of the shuttle valve cavity.

4. The gas-driven compressor system of claim 3, wherein the first groove is aligned with a first shuttle valve signal line when the first head of the piston is in a first position in the first piston cavity, and wherein the second groove is aligned with a second shuttle valve signal line when the first head of the piston is in a second position in the first piston cavity.

5. The gas-driven compressor system of claim 3, wherein the first groove is axially spaced from the second groove along the piston, and the high pressure port is in communication with the piston along a first inlet signal line arranged to pressurize the first groove when the first head of the piston is at a first end of the first piston cavity and a second inlet signal line arranged to pressurize the second groove when the first head of the piston is at a second end of the first piston cavity.

6. The gas-driven compressor system of claim 3, wherein the first groove and the second groove are included on the second head of the piston.

7. The gas-driven compressor system of claim 1, further comprising: ​ a lever that couples the first head to the second head.

8. The gas driven compressor system of claim 1, wherein the first head of the piston divides the first piston cavity into a first volume and a second volume; wherein the shuttle valve in the first position provides the pressurized input stream to the first volume and vents the second volume to the low pressure port to move the piston in a first direction; and wherein the shuttle valve in the second position provides the pressurized input stream to the second volume and vents the first volume to the low pressure port to move the piston in a second, opposite direction.

9. A method of compressing a fluid using a process gas driven compressor, the method comprising: providing a high pressure port of a compressor body in communication with a first pressure; providing a low pressure port of the compressor body in communication with a second pressure; and moving a shuttle valve in response to a pressure differential between the high pressure port and the low pressure port to move a first piston in a reciprocating motion within a first piston cavity, the movement of the shuttle valve selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston within the first piston cavity as a function of a position of a piston assembly comprising the first piston; the movement of the first piston moving a second piston of the piston assembly in a reciprocating motion within a second piston cavity to compress a fluid within the second piston cavity.

10. The method of claim 9, further comprising: aligning a first circumferential groove of the piston assembly with a first shuttle valve signal line when the piston assembly is in a first position to direct pressurized fluid from the high pressure port to a first side of the shuttle valve to move the shuttle valve from a first position to a second position; and aligning a second circumferential groove of the piston assembly with a second shuttle valve signal line when the piston assembly is in a second position to direct high pressure fluid to a second side of the shuttle valve to move the shuttle valve from the second position back to the first position.

11. The method of claim 9, further comprising: discharging the compressed fluid from the second piston cavity through a compressor outlet port when the compressed fluid reaches a predetermined threshold pressure.

12. The method of claim 9, further comprising: selectively blocking fluid communication between the high pressure port and the shuttle valve signal lines with the piston assembly during the reciprocating motion of the first and second pistons.

13. The method of claim 9, wherein, sucking fluid into the second piston cavity includes: sucking fluid into the second piston cavity through an inlet port and a first check valve during movement of the piston from the first position to the second position.

14. The method of claim 9, wherein the fluid compressed in the second piston cavity is further compressed in a second stage of compression by the reciprocating motion of the piston assembly.

15. The method of claim 14, wherein the reciprocating motion of the piston assembly directs the compressed fluid from the second piston cavity to a third piston cavity to compress the compressed fluid by the reciprocating motion of the piston assembly.

16. A gas driven compressor system, comprising: high pressure port; low pressure port; a piston assembly, the piston assembly comprising: a first piston movable within a first piston cavity in response to a pressure differential between the high pressure port and the low pressure port; and a second piston movable within a second piston cavity by movement of the first piston to compress a fluid within the second piston cavity; and a shuttle valve movable between a first position and a second position in response to the pressure differential between the high pressure port and the low pressure port to cause reciprocating motion of the piston assembly by selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston depending on a position of the piston assembly.

17. The gas driven compressor system of claim 16, further comprising: a lever mechanically coupled between the first piston and the second piston to multiply a force applied by the first piston to the second piston.

18. The gas driven compressor system of claim 16, wherein the second piston comprises a first bulkhead and a second bulkhead secured together by a piston rod.

19. The gas driven compressor system of claim 18, wherein the first bulkhead forms a first chamber comprising an inlet port and an outlet port, and wherein the second bulkhead forms a second chamber comprising a port to atmosphere.

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