METHOD OF PRODUCING COMPRESSED AIR VIA ENERGY EXCHANGE WITH COMPRESSED NATURAL GAS

Abstract

A compression exchange apparatus that includes a first compression cylinder and a first inlet to allow the compression exchange apparatus to receive compressed natural gas. The compression exchange apparatus also includes a second inlet to allow the compression exchange apparatus to receive air at a first pressure and a first outlet of the compression exchange apparatus for providing decompressed natural gas generated by decompressing the compressed natural gas in the compression exchange apparatus a path to escape the compression exchange apparatus. The compression exchange apparatus can also include a second outlet of the compression exchange apparatus for providing compressed air at a higher second pressure to exit the compression exchange apparatus and a first piston in the first compression cylinder to transfer the energy of the compressed natural gas into compressing the air at the first pressure to generate the compressed air at the higher second pressure. A method that includes the steps of capturing energy contained in a compressed gas via a compression exchange apparatus operating only mechanically and generating compressed air from the energy captured from the compressed gas.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE DISCLOSURE

1. Field of the Invention

The present disclosure generally relates to compressing atmospheric air through an energy exchange with compressed natural gas and a compression exchange apparatus that can be used to accomplish the energy exchange.

2. Description of the Related Art

In certain operations, compressed natural gas is used to operate pneumatic devices in industrial settings. Examples of these pneumatic devices include, but are not limited to, pressure control valves, transfer pumps, chemical injection pumps, liquid dump valves, throttle valves, pneumatic level controllers for vessels. A downside of using compressed natural gas with these pneumatic devices is that natural gas is released into the atmosphere during that use. Natural gas comprises at least 50% methane, which is a greenhouse gas and is potentially more harmful to the atmosphere than air. Natural gas also includes other potentially harmful gases. Currently, to avoid discharge of natural gas into the atmosphere, the compressed natural gas is decompressed and then piped and/or transported for reuse, proper combustion or disposal.

Accordingly, there is a need for the ability to use the compressed natural gas and the energy contained therein productively without discharging the natural gas to the atmosphere before properly handling the natural gas without releasing it to the atmosphere.

SUMMARY OF THE DISCLOSURE

The present disclosure is directed to a compression exchange apparatus that includes a first compression cylinder and a first inlet to allow the compression exchange apparatus to receive compressed natural gas. The compression exchange apparatus also includes a second inlet to allow the compression exchange apparatus to receive air at a first pressure and a first outlet of the compression exchange apparatus for providing decompressed natural gas generated by decompressing the compressed natural gas in the compression exchange apparatus a path to escape the compression exchange apparatus. The compression exchange apparatus can also include a second outlet of the compression exchange apparatus for providing compressed air at a higher second pressure to exit the compression exchange apparatus and a first piston in the first compression cylinder to transfer the energy of the compressed natural gas into compressing the air at the first pressure to generate the compressed air at the higher second pressure.

The present disclosure is also directed to a method that includes the steps of capturing energy contained in a compressed gas via a compression exchange apparatus operating only mechanically and generating compressed air from the energy captured from the compressed gas.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are cross-sectional views of one embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIG. 2 is a cross-sectional view of another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIG. 3 is a cross-sectional view of yet another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIG. 4 is a cross-sectional view of a further embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIG. 5 is a cross-sectional view of another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIGS. 6A-6C provide multiple views of yet another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIG. 7 is a cross-sectional view of another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIGS. 8A and 8B are cross-sectional views of another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIGS. 9A-9B provide multiple views of yet another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

FIG. 10 is a cross-sectional view of yet another embodiment of a compression exchange apparatus constructed in accordance with the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

The present disclosure is related to a method of using energy contained in compressed natural gas to compress air for various uses, such as for use in various pneumatic devices. The present disclosure is also directed to a compression exchange apparatus 10 that can be used to convert the energy in the compressed natural gas to compressed air. The method and apparatus 10 convert the energy of the compressed natural gas to compressed air without the use of electricity or batteries (i.e., only mechanically) and without the use of any combustion. The compression exchange apparatus 10 can be set up to convert the energy in the compressed natural gas to a lower pressure and higher volume of compressed air than the volume and pressure of the input compressed natural gas. Alternatively, the compression exchange apparatus 10 can be set up to convert the energy in the compressed natural gas to a higher pressure and lower volume of compressed air than the volume and pressure of the input compressed natural gas. The compression exchange apparatus 10 can also be set up to convert the energy in the compressed natural gas to roughly the equivalent pressure and volume of compressed air as that of the volume and pressure of the input compressed natural gas. The compressed natural gas can be captured or produced in any manner known to one of ordinary skill in the art. The compressed air generated can be captured and stored or used for any desired purpose known to one of ordinary skill in the art.

Referring now to FIGS. 1A and 1B, shown therein is one embodiment of the compression exchange apparatus 10. In this embodiment, the compression exchange apparatus 10 includes a first compression chamber 12 that includes a first diaphragm 14 for compressing air using compressed natural gas and a second compression chamber 16 that includes a second diaphragm 18 for compressing air using compressed natural gas. The first compression chamber 12 includes an air inlet 20 for receiving air and a compressed air outlet 22 for allowing the compressed air generated in the first compression chamber 12 a means to exit the first compression chamber 12. Similarly, the second compression chamber 16 includes an air inlet 24 for receiving air and a compressed air outlet 26 for allowing the compressed air generated in the second compression chamber 16 a means to exit the second compression chamber 16. The air inlets 20, 24 and the compressed air outlets 22, 26 can include check valves 27 to allow movement of the gases to flow only in the desired direction.

The compression exchange apparatus 10 also includes a valve chamber 28 for receiving the compressed natural gas and directing the compressed natural gas between the first and second compression chambers 12 and 16. The valve chamber 28 can include a compressed natural gas inlet 30 for receiving the compressed natural gas into the valve chamber 28 and a natural gas outlet 32 for providing a means for the decompressed natural gas to exit the valve chamber 28. The valve chamber 28 can include an oscillating valve 34 for directing the incoming compressed natural gas from the compressed natural gas inlet 30 to the first compression chamber 12 and the second compression chamber 16 via a first conduit 38 and a second conduit that are in fluid communication with the first and second compression chambers 12 and 16, respectively. The valve chamber 28 can also include a first decompressed natural gas outlet 40 for delivering the decompressed natural gas from the first compression chamber 12 to the natural gas outlet 32 and a second decompressed natural gas outlet 42 for delivering the decompressed natural gas from the second compression chamber 16 to the natural gas outlet 32. The compressed natural gas inlet, the natural gas outlet 32 and first and second decompressed natural gas outlets 42 can also include check valves 27 to allow movement of the gases to flow only in the desired direction. The oscillating valve 34 can be any type of valve known in the art capable of functioning as described herein. For example, the oscillating valve 34 can be mechanically or electrically operated.

The compression exchange apparatus 10 can also include a linkage device 44 that mechanically connects the first and second diaphragms 14 and 18 such that movement of one diaphragm causes movement of the other diaphragm. In one embodiment, the linkage device 44 can be a rod that can extend through the valve chamber 32 and is connected to both the first and second diaphragms 14 and 18. The linkage device 44 causes each of the first and second diaphragms 14 and 18 to move between first and second positions. In another embodiment, the compression exchange apparatus 10 does not include a linkage device 44. Rather, each compression chamber 12 and 16 can include a biasing mechanism, such as a spring, (not shown) to move the first and second diaphragms 14 and 18 back to a first position in each respective compression chamber 12 and 16 from a second position.

The first compression chamber 12 has an air side 46 and a natural gas side 48. Similarly, the second compression chamber 16 has an air side 50 and a natural gas side 52. When the linkage device 44 is incorporated in the compression exchange apparatus 10 as shown in FIG. 1A, the first position of the first diaphragm 14 is when the air side 46 of the first compression chamber 12 is compressed, the natural gas side 48 of the first compression chamber 12 is expanded, the first position of the second diaphragm 18 is when the air side 50 of the second compression chamber 16 is expanded, and the natural gas side 52 of the second compression chamber 16 is compressed. Conversely, when the linkage device 44 is incorporated in the compression exchange apparatus 10 as shown in FIG. 1B, the second position of the first diaphragm 14 is when the air side 46 of the first compression chamber 12 is expanded, the natural gas side 48 of the first compression chamber 12 is compressed, the first position of the second diaphragm 18 is when the air side 50 of the second compression chamber 16 is compressed, and the natural gas side 52 of the second compression chamber 16 is expanded. It should be understood and appreciated that when the natural gas sides 48 and 52 are “compressed,” it only means that the decompressed natural gas is forced into and out of the valve chamber 32.

As the first diaphragm 14 is moved from the first position to the second position, air is pulled into the first compression chamber 12 via the air inlet 20. Similarly, as the second diaphragm 18 is moved from the second position to the first position, air is pulled into the second compression chamber 16 via the air inlet 24. Conversely, as the first diaphragm 14 is moved from the second position to the first position via the compressed natural gas being forced into the natural gas side 48 of the first compression chamber 12 by the oscillating valve 34, air is compressed in the first compression chamber 12 and exits the first compression chamber 12 via the compressed air outlet 22. Similarly, as the second diaphragm 18 is moved from the first position to the second position, via the compressed natural gas being forced into the natural gas side 52 of the second compression chamber 16 by the oscillating valve 34, air is compressed in the second compression chamber 16 and exits the second compression chamber 162 via the compressed air outlet 26.

When a biasing mechanism is used, the first position of the first and second diaphragms 14 and 18 are when the air sides 46 and 50 of the first and second compression chambers 12 and 16 are compressed. Conversely, the second position of the first and second diaphragms 14 and 18 are when the air sides 46 and 50 of the first and second compression chambers 12 and 16 are expanded. The biasing mechanisms bring the first and second diaphragms 14 and 18 back into the first position after the compressed natural gas forces the first and second diaphragms 14 and 18 into the second position, which compresses the air in the air sides 46 and 50 of the first and second compression chambers 12 and 16, respectively.

Referring now to FIGS. 2-4, shown therein are other embodiments of the compression exchange apparatus 10. FIG. 2 shows the compression exchange apparatus 10 including a first compression chamber 54 that includes a first diaphragm 56 for compressing air using compressed natural gas and a second compression chamber 58 that includes a second diaphragm 60 for compressing air using compressed natural gas. The first compression chamber 54 includes a natural gas inlet 62 for receiving compressed natural gas and a natural gas outlet 64 for allowing the decompressed natural gas a means to exit the first compression chamber 54. The second compression chamber 58 includes an air inlet 66 for receiving air and a compressed air outlet 68 for allowing the compressed air generated in the second compression chamber 58 a means to exit the second compression chamber 58. The air inlet 66, the compressed air outlet 68, the compressed natural gas inlet 62 and the natural gas outlet 64 can include check valves 27 to allow movement of the gases to flow only in the desired direction.

The compression exchange apparatus 10 shown in FIGS. 2-4 can also include piston apparatus 70 disposed between the first and second compression chambers 54 and 58 to transfer the energy of the compressed natural gas in the first compression chamber 54 to the air drawn into the second compression chamber 58. The piston apparatus 70 can include a first piston 72 in fluid communication with the first diaphragm 56 and slidably disposed within a first piston sleeve 74 connected to the first compression chamber 54. The piston apparatus 70 can also include a second piston 76 in fluid communication with the first diaphragm 60 and slidably disposed within a second piston sleeve 78 connected to the second compression chamber 58. The first and second pistons 72 and 76 can be connected by a linkage device 80 to transfer movement from one piston to the other. The piston apparatus 70 can include any number of parts and elements such that the motion of the first diaphragm 56 is transferred to the second diaphragm 60. In another embodiment, the piston apparatus 70 could include just a single piston disposed in a single piston sleeve that connects the first and second compression chambers 54 and 58.

The first compression chamber 54 can have a natural gas side 82 where the compressed natural gas enters and exits and an energy transfer side 84 where the energy from the compressed natural gas is transferred to the second diaphragm 60 in the second compression chamber 58. The second compression chamber 58 can have an energy transfer side 86 where the energy from the compressed natural gas is received from the first diaphragm 56 in the first compression chamber 54 and an air side 88 where the air is compressed.

The compression exchange apparatus 10 can include a first bias mechanism 90 (such as a spring) in the first compression chamber 54 to pull the first diaphragm 56 towards a first position 92 in the first compression chamber 54. When the compressed natural gas enters the first compression chamber 54, the first diaphragm 56 is forced into a second position 94 in the first compression chamber 54. Forcing the first diaphragm 56 into the second position 94 causes the piston(s) 72, 76 and the linkage device 80 of the piston apparatus to shift towards the second diaphragm 60 in the second compression chamber 58. The second compression chamber 58 also includes a biasing mechanism 96 (such as a spring) that pulls the second diaphragm 60 towards a first position 100 in the second compression chamber 58. When the piston(s) 72, 76 and the linkage device 80 of the piston apparatus to shift towards the second diaphragm 60 in the second compression chamber 58, the second diaphragm 60 is forced into its second position 102. The air in the second compression chamber 58 is compressed and forced out of the second compression chamber 58 via the compressed air outlet 68 when the second diaphragm 60 is forced into the second position 102. The first and second compression chambers 54 and 58 can include bleeder holes (not shown) to allow air to flow in and out of the energy transfer sides 84 and 86 of the compression chambers 54 and 58. In another embodiment, air is permitted to flow in and out of the energy transfer sides 84 and 86 of the compression chambers 54 and 58 via open areas of the piston apparatus 70.

In certain situations, it is desired to generate a higher volume of compressed air with a lower pressure than the volume and pressure of the compressed natural gas that is fed to the compression exchange apparatus 10. In this embodiment, shown in more detail in FIG. 2, the second diaphragm 60 and the second compression chamber 58 are larger than the first diaphragm 56 and the first compression chamber 54. The size difference between the first and second compression chambers 54 and 58 and the first and second diaphragms 58 and 60 depends on the desired volume and pressure differences between the compressed natural gas to be used and the compressed air generated.

In other situations, it is desirable to generate a lower volume of compressed air with a higher pressure than the volume and pressure of the compressed natural gas that is fed to the compression exchange apparatus 10. In this embodiment, shown in more detail in FIG. 3, the second diaphragm 60 and the second compression chamber 58 are smaller than the first diaphragm 56 and the first compression chamber 54. The size difference between the first and second compression chambers 54 and 58 and the first and second diaphragms 58 and 60 depends on the desired volume and pressure differences between the compressed natural gas to be used and the compressed air generated.

In another embodiment of the present disclosure shown in more detail in FIG. 5, the compression exchange apparatus 10 can include a single compression chamber 104 that includes a diaphragm 106 for compressing air using compressed natural gas. The compression chamber 104 has a gas side 108 and an air side 110. The air side includes an air inlet 112 for receiving air and a compressed air outlet 114 for allowing the compressed air generated in the compression chamber 104 a means to exit the compression chamber 104. The gas side 108 includes a compressed natural gas inlet 116 for receiving compressed natural gas and a natural gas outlet 118 for allowing the natural gas to escape the compression chamber 104 after the energy of the compressed natural gas has been used to compress the air on the air side 110 of the compression chamber 104. The compression chamber 104 can also include a biasing mechanism 120 (such as a spring) to manipulate the position of the diaphragm 106 in the compression chamber 104 towards a first position more in the direction of the gas side 108 of the compression chamber 104. In another embodiment, the compression chamber 104 can be replaced by a compression cylinder and the diaphragm 106 can be replaced by a piston.

As compressed natural gas is forced into the gas side 108 of the compression chamber 104, the diaphragm 106 is forced from the first position towards the air side 110 of the compression chamber 104. When the compressed natural gas forces the diaphragm 106 from the first position to a second position in the compression chamber 104, the air in the air side 110 of the compression chamber 104 is compressed to create the compressed air and the compressed air is forced out of the compression chamber 104. After the air has been compressed, the biasing mechanism 120 pulls the diaphragm 106 back into the first position.

In an even further embodiment of the present disclosure shown in more detail in FIGS. 6A-6C, the compression exchange apparatus 10 includes a first compression chamber 130 that includes a first diaphragm 132 for capturing the energy from compressed natural gas and a second compression chamber 134 that includes a second diaphragm 136 for transferring the energy from the compressed natural gas and using the energy from the compressed natural gas to compress air. The first compression chamber 130 includes a first compressed natural gas inlet 138 for receiving compressed natural gas on a first side 140 of the first compression chamber 130 and a second compressed natural gas inlet 142 for allowing compressed natural gas to flow into a second side 144 of the first compression chamber 130. The first and second sides 140 and 144 of the first compression chamber 130 are separated by the first diaphragm 132. The second compression chamber 134 includes a first compressed air outlet 146 for allowing compressed air generated on a first side 148 of the second compression chamber 134 to escape the second compression chamber 134 and a second compressed air outlet 150 for allowing compressed air to flow out of a second side 152 of the second compression chamber 134. The first and second sides 148 and 152 of the second compression chamber 134 are separated by the second diaphragm 136.

The first compression chamber 130 includes a first compressed natural gas outlet 154 for allowing decompressed natural gas on the first side 140 of the first compression chamber 130 to escape the first compression chamber 130 and a second compressed natural gas outlet 156 for allowing decompressed natural gas to flow out of the second side 144 of the first compression chamber 130. The second compression chamber 134 includes a first air inlet 146 for allowing air to be received on the first side 148 of the second compression chamber 134 and a second air inlet 160 for allowing air to flow into the second side 152 of the second compression chamber 134.

The compression exchange apparatus 10 can also include a valve apparatus 162 to switch the flow of compressed natural gas into the first compression chamber 130 between the first and second compressed natural gas inlets 138 and 142. The valve apparatus 162 can include an oscillating valve 164 for directing the incoming compressed natural gas between the first compressed natural gas inlet 138 of the first compression chamber 130 and the second compressed natural gas inlet 142 of the first compression chamber 130 via a first conduit 166 and a second conduit 168 that are in fluid communication with the first and second compressed natural gas inlets 138 and 142, respectively. The control valve 164 can be any type of valve capable of switching the flow of compressed natural gas between the first compression chamber 130 and the second compressed natural gas inlet 142 of the first compression chamber 130. The control valve 164 can be switched/operated in any manner known in the art. The compression exchange apparatus 10 also includes a linkage device 170 that mechanically connects the first and second diaphragms 132 and 136 such that movement of one diaphragm causes movement of the other diaphragm. In one embodiment, the linkage device 170 can be a rod that can is attached to both the first and second diaphragms 132 and 136. The linkage device 170 causes each of the first and second diaphragms 132 and 136 to move between first and second positions.

In one embodiment, the valve apparatus 162 can include a first pilot valve 172 and a second pilot valve 174 that work with a rod element 176 attached to the linkage device 170 to switch the control valve 164 to direct the compressed natural gas between the first and second compressed natural gas inlets 138 and 142. The first and second pilot valves 172 and 174 are connected to the control valve 164 via conduits 178 that allows air, or some other gas or fluid, to flow therebetween. As the linkage device 170 moves back and forth, the rod element 176 alternatingly engages the first and second pilot valves 172 and 174, which causes the air in the conduits 178 to flow to the control valve 164 and switch which inlet 138 and 142 the compressed natural gas is directed to. The pilot valves 172 and 174 can be any type of pilot valve known in the art capable of operating as desired. For example, the pilot valves 172 and 174 can be cam valves.

In use, the control valve 164 directs the compressed natural gas into the first side 140 of the first compression chamber 130 (and thus the first diaphragm 132). The compressed natural gas causes the first diaphragm 132 to shift from a first position in the first chamber 130 to a second position in the first compression chamber 130. The first diaphragm 132 shifting from the first position to the second position causes the second diaphragm 136, via the linkage device 170, to shift from a first position in the second compression chamber 134 to a second position in the second compression chamber 134. When the second diaphragm 136 is forced towards the second position in the second compression chamber 134, air in the second side 152 of the second compression chamber 134 is compressed and permitted to exit the second compression chamber 134 via the second compressed air outlet 150.

The control valve 164 can then direct the compressed natural gas into the second side 144 of the first compression chamber 130 (and thus the first diaphragm 132). The compressed natural gas causes the first diaphragm 132 to shift from the second position in the first chamber 130 back to the first position in the first compression chamber 130. The first diaphragm 132 shifting from the second position to the first position causes the second diaphragm 136, via the linkage device 170, to shift from its second position in the second compression chamber 134 back to the first position in the second compression chamber 134. When the second diaphragm 136 is forced towards its first position in the second compression chamber 134, air in the first side 148 of the second compression chamber 134 is compressed and permitted to exit the second compression chamber 134 via the first compressed air outlet 146. As the compressed natural gas is directed back and forth between the first and second compressed natural gas inlets 138 and 142, compressed air is generated in both sides 148 and 152 second compression chamber 134.

In another embodiment shown in FIG. 7, the second compression chamber 134 can be larger than the first compression chamber 130 so that a lower pressure and higher volume of compressed air can be generated in the second compression chamber 134 with the compressed natural gas entering the smaller first compression chamber 130. Since the second compression chamber 134 is bigger than the first compression chamber 130, the second diaphragm 136 is larger than the first diaphragm 132. The Referring now to FIGS. 8A and 8B, shown therein is another embodiment of a compression exchange apparatus 210. In this embodiment, the compression exchange apparatus 210 includes a first compression cylinder 212 that includes a first piston 214 for compressing air using compressed natural gas and a second compression cylinder 216 that includes a second piston 218 for compressing air using compressed natural gas. The first compression cylinder 212 includes an air inlet 220 for receiving air and a compressed air outlet 222 for allowing the compressed air generated in the first compression cylinder 212 a means to exit the first compression cylinder 212. Similarly, the second compression cylinder 216 includes an air inlet 24 for receiving air and a compressed air outlet 26 for allowing the compressed air generated in the second compression cylinder 216 a means to exit the second compression cylinder 216. The air inlets 220, 224 and the compressed air outlets 222, 226 can include check valves 227 to allow movement of the gases to flow only in the desired direction.

The compression exchange apparatus 210 also includes a valve chamber 228 for receiving the compressed natural gas and directing the compressed natural gas between the first and second compression cylinders 212 and 216. The valve chamber 228 can include a compressed natural gas inlet 230 for receiving the compressed natural gas into the valve chamber 228 and a natural gas outlet 232 for providing a means for the decompressed natural gas to exit the valve chamber 228. The valve chamber 228 can include an oscillating valve 234 for directing the incoming compressed natural gas from the compressed natural gas inlet 230 to the first compression cylinder 212 and the second compression cylinder 16 via a first conduit 236 and a second conduit 238 that are in fluid communication with the first and second compression cylinders 212 and 216, respectively. The valve chamber 228 can also include a first decompressed natural gas outlet 240 for delivering the decompressed natural gas from the first compression cylinder 212 to the natural gas outlet 232 and a second decompressed natural gas outlet 242 for delivering the decompressed natural gas from the second compression cylinder 216 to the natural gas outlet 232. The compressed natural gas inlet, the natural gas outlet 232 and first and second decompressed natural gas outlets 242 can also include check valves 227 to allow movement of the gases to flow only in the desired direction. The oscillating valve 234 can be any type of valve known in the art capable of functioning as described herein. For example, the oscillating valve 234 can be mechanically or electrically operated.

The compression exchange apparatus 210 can also include a linkage device 244 that mechanically connects the first and second pistons 214 and 218 such that movement of one piston causes movement of the other piston. In one embodiment, the linkage device 244 can be a rod that can extend through the valve chamber 232 and is connected to both the first and second pistons 214 and 218. The linkage device 244 causes each of the first and second pistons 214 and 218 to move between first and second positions. In another embodiment, the compression exchange apparatus 210 does not include a linkage device 244.

The first compression cylinder 212 has an air side 246 and a natural gas side 248. Similarly, the second compression cylinder 216 has an air side 250 and a natural gas side 252. When the linkage device 244 is incorporated in the compression exchange apparatus 210 as shown in FIG. 8A, the first position of the first piston 214 is when the air side 246 of the first compression cylinder 212 is compressed, the natural gas side 248 of the first compression cylinder 212 is expanded, the first position of the second piston 218 is when the air side 250 of the second compression cylinder 216 is expanded, and the natural gas side 252 of the second compression cylinder 216 is compressed. Conversely, when the linkage device 244 is incorporated in the compression exchange apparatus 210 as shown in FIG. 8B, the second position of the first piston 214 is when the air side 246 of the first compression cylinder 212 is expanded, the natural gas side 248 of the first compression cylinder 212 is compressed, the first position of the second piston 218 is when the air side 250 of the second compression cylinder 216 is compressed, and the natural gas side 252 of the second compression cylinder 216 is expanded. It should be understood and appreciated that when the natural gas sides 248 and 252 are “compressed,” it only means that the decompressed natural gas is forced into and out of the valve chamber 232.

As the first piston 214 is moved from the first position to the second position, air is pulled into the first compression cylinder 212 via the air inlet 220. Similarly, as the second piston 218 is moved from the second position to the first position, air is pulled into the second compression cylinder 216 via the air inlet 224. Conversely, as the first piston 214 is moved from the second position to the first position via the compressed natural gas being forced into the natural gas side 248 of the first compression cylinder 212 by the oscillating valve 234, air is compressed in the first compression cylinder 212 and exits the first compression cylinder 212 via the compressed air outlet 222. Similarly, as the second piston 218 is moved from the first position to the second position, via the compressed natural gas being forced into the natural gas side 252 of the second compression cylinder 216 by the oscillating valve 234, air is compressed in the second compression cylinder 216 and exits the second compression cylinder 216 via the compressed air outlet 226.

It should be understood and appreciated that the first compression chamber 12 and first diaphragm 14 described herein and shown in FIGS. 1A and 1B can be incorporated and used in place of the first compression cylinder 212 and first piston 214 described herein and shown in FIGS. 8A and 8B. In certain situations, it is desired to generate a higher volume of compressed air with a lower pressure than the volume and pressure of the compressed natural gas that is fed to the compression exchange apparatus 210. In this embodiment, the second piston 218 and the second compression cylinder 216 are larger than the first piston 214 and the first compression cylinder 212. The size difference between the first and second compression cylinders 212 and 216 and the first and second pistons 214 and 218 depends on the desired volume and pressure differences between the compressed natural gas to be used and the compressed air generated.

In other situations, it is desired to generate a lower volume of compressed air with a higher pressure than the volume and pressure of the compressed natural gas that is fed to the compression exchange apparatus 210. In this embodiment, the second piston 218 and the second compression cylinder 216 are smaller than the first piston 214 and the first compression cylinder 212. The size difference between the first and second compression cylinders 212 and 216 and the first and second pistons 214 and 218 depends on the desired volume and pressure differences between the compressed natural gas to be used and the compressed air generated.

In yet another embodiment of the present disclosure shown in more detail in FIGS. 9A and 9B, the compression exchange apparatus 310 includes a first compression cylinder 330 that includes a first piston 332 for capturing the energy from compressed natural gas and a second compression cylinder 334 that includes a second piston 336 for transferring the energy from the compressed natural gas and using the energy from the compressed natural gas to compress air. The first compression cylinder 330 includes a first compressed natural gas inlet 338 for receiving compressed natural gas on a first side 340 of the first compression cylinder 330 and a second compressed natural gas inlet 342 for allowing compressed natural gas to flow into a second side 344 of the first compression cylinder 330. The first and second sides 340 and 344 of the first compression cylinder 330 are separated by the first piston 332. The second compression cylinder 334 includes a first compressed air outlet 346 for allowing compressed air generated on a first side 348 of the second compression cylinder 334 to escape the second compression cylinder 334 and a second compressed air outlet 350 for allowing compressed air to flow out of a second side 352 of the second compression cylinder 334. The first and second sides 348 and 352 of the second compression cylinder 334 are separated by the second piston 336.

The first compression cylinder 330 includes a first compressed natural gas outlet 354 for allowing decompressed natural gas on the first side 340 of the first compression cylinder 330 to escape the first compression cylinder 330 and a second compressed natural gas outlet 356 for allowing decompressed natural gas to flow out of the second side 344 of the first compression cylinder 330. The second compression cylinder 334 includes a first air inlet 346 for allowing air to be received on the first side 348 of the second compression cylinder 334 and a second air inlet 360 for allowing air to flow into the second side 352 of the second compression cylinder 334.

The compression exchange apparatus 310 can also include a valve apparatus 362 to switch the flow of compressed natural gas into the first compression cylinder 330 between the first and second compressed natural gas inlets 338 and 342. The valve apparatus 362 can include an oscillating valve 364 for directing the incoming compressed natural gas between the first compressed natural gas inlet 338 of the first compression cylinder 330 and the second compressed natural gas inlet 342 of the first compression cylinder 330 via a first conduit 366 and a second conduit 368 that are in fluid communication with the first and second compressed natural gas inlets 338 and 342, respectively. The control valve 364 can be any type of valve capable of switching the flow of compressed natural gas between the first compression cylinder 330 and the second compressed natural gas inlet 342 of the first compression cylinder 330. The control valve 364 can be switched/operated in any manner known in the art. The compression exchange apparatus 310 also includes a linkage device 370 that mechanically connects the first and second pistons 332 and 336 such that movement of one piston causes movement of the other piston. In one embodiment, the linkage device 370 can be a rod that can is attached to both the first and second pistons 332 and 336. The linkage device 370 causes each of the first and second pistons 332 and 336 to move between first and second positions.

In one embodiment, the valve apparatus 362 can include a first pilot valve 372 and a second pilot valve 374 that work with a rod element 376 attached to the linkage device 370 to switch the control valve 364 to direct the compressed natural gas between the first and second compressed natural gas inlets 338 and 342. The first and second pilot valves 372 and 374 are connected to the control valve 364 via conduits 378 that allows air, or some other gas or fluid, to flow therebetween. As the linkage device 370 moves back and forth, the rod element 376 alternatingly engages the first and second pilot valves 372 and 374, which causes the air in the conduits 378 to flow to the control valve 364 and switch which inlet 338 and 342 the compressed natural gas is directed to. The pilot valves 372 and 374 can be any type of pilot valve known in the art capable of operating as desired. For example, the pilot valves 372 and 374 can be cam valves.

In use, the control valve 364 directs the compressed natural gas into the first side 340 of the first compression cylinder 330 (and thus the first piston 332). The compressed natural gas causes the first piston 332 to shift from a first position in the first cylinder 330 to a second position in the first compression cylinder 330. The first piston 332 shifting from the first position to the second position causes the second piston 336, via the linkage device 370, to shift from a first position in the second compression cylinder 334 to a second position in the second compression cylinder 334. When the second piston 336 is forced towards the second position in the second compression cylinder 334, air in the second side 352 of the second compression cylinder 334 is compressed and permitted to exit the second compression cylinder 334 via the second compressed air outlet 350.

The control valve 364 can then direct the compressed natural gas into the second side 344 of the first compression cylinder 330 (and thus the first piston 332). The compressed natural gas causes the first piston 332 to shift from the second position in the first cylinder 330 back to the first position in the first compression cylinder 330. The first piston 332 shifting from the second position to the first position causes the second piston 336, via the linkage device 370, to shift from its second position in the second compression cylinder 334 back to the first position in the second compression cylinder 334. When the second piston 336 is forced towards its first position in the second compression cylinder 334, air in the first side 348 of the second compression cylinder 334 is compressed and permitted to exit the second compression cylinder 334 via the first compressed air outlet 346. As the compressed natural gas is directed back and forth between the first and second compressed natural gas inlets 338 and 342, compressed air is generated in both sides 348 and 352 second compression cylinder 334.

In another embodiment shown in FIG. 10, the second compression cylinder 334 can be larger than the first compression cylinder 330 so that a lower pressure and higher volume of compressed air can be generated in the second compression cylinder 334 with the compressed natural gas entering the smaller first compression cylinder 330. Since the second compression cylinder 334 is bigger than the first compression chamber 330, the second piston 336 is larger than the first piston 332.

From the above description, it is clear that the present disclosure is well-adapted to carry out the objectives and to attain the advantages mentioned herein as well as those inherent in the disclosure. While presently preferred embodiments have been described herein, it will be understood that numerous changes may be made which will readily suggest themselves to those skilled in the art and which are accomplished within the spirit of the disclosure and claims.

Claims

1. A compression exchange apparatus, the compression exchange apparatus comprising: a first compression cylinder;a first inlet to allow the compression exchange apparatus to receive compressed natural gas;a second inlet to allow the compression exchange apparatus to receive air at a first pressure;a first outlet of the compression exchange apparatus for providing decompressed natural gas generated by decompressing the compressed natural gas in the compression exchange apparatus a path to escape the compression exchange apparatus;a second outlet of the compression exchange apparatus for providing compressed air at a higher second pressure to exit the compression exchange apparatus; anda first piston in the first compression cylinder to transfer the energy of the compressed natural gas into compressing the air at the first pressure to generate the compressed air at the higher second pressure.

2. The apparatus of claim 1 wherein the first and second inlets and the first and second outlets are disposed in the first compression cylinder, the first inlet and the first outlet disposed on one side of the first piston and the second inlet and the second outlet are disposed on an opposite side of the first piston.

3. The apparatus of claim 1 wherein the compression exchange apparatus further comprises a second compression cylinder that includes a second piston disposed therein.

4. The apparatus of claim 3 wherein the first inlet and the first outlet are disposed in the first compression cylinder in fluidic communication with a first side of the first piston and the second inlet and the second outlet are disposed in the second compression cylinder in fluidic communication with a first side of the second piston.

5. The apparatus of claim 4 further comprising: a third inlet in fluidic communication with a second side of the first piston to allow compressed natural gas to enter the first compression cylinder on the second side of the first piston;a second inlet in fluidic communication with a second side of the second piston to receive air at a third pressure;a first outlet in fluidic communication with the second side of the first piston for providing decompressed natural gas generated by decompressing the compressed natural gas in the second side a path to escape the first compression cylinder;a second outlet in fluidic communication with the second side of the second piston for providing compressed air at a higher fourth pressure than the air entering the second compression cylinder at the third pressure to exit the second compression cylinder, the second piston in the second compression cylinder to transfer the energy of the compressed natural gas into compressing the air at the third pressure to generate the compressed air at the higher fourth pressure.

6. The apparatus of claim 5 further comprising an oscillating control valve to direct a feed of compressed natural gas alternatingly between the first inlet and the third inlet of the first compression cylinder.

7. The apparatus of claim 5 further comprising a linkage device that is connected on one end to the first piston and connected on a second end to the second piston to transfer movement of the first piston to the second piston and to transfer movement of the second piston to the first piston.

8. The apparatus of claim 1 operating without electronic power or combustion.

9. A method, the method comprising: capturing energy contained in compressed natural gas via a compression exchange apparatus operating only mechanically, the compression exchange apparatus comprising: a first compression cylinder having a cylinder wall;a first inlet disposed directly in the cylinder wall to allow the compression exchange apparatus to receive compressed natural gas;a second inlet disposed directly in the cylinder wall to allow the compression exchange apparatus to receive air at a first pressure;a first outlet disposed directly in the cylinder wall of the compression exchange apparatus for providing decompressed natural gas generated by decompressing the compressed natural gas in the compression exchange apparatus a path to escape the compression exchange apparatus;a second outlet disposed directly in the cylinder wall of the compression exchange apparatus for providing compressed air at a higher second pressure to exit the compression exchange apparatus; anda first piston in the first compression cylinder to transfer the energy of the compressed natural gas into compressing the air at the first pressure to generate the compressed air at the higher second pressure; andgenerating compressed air from the energy captured from the compressed natural gas.

10. The method of claim 9 further comprising storing the compressed air or using the compressed air to operate various devices.

11. The method of claim 9 wherein the generated compressed air has a higher volume and a lower pressure than the compressed natural gas fed to the compression exchange apparatus.

12. The method of claim 9 wherein the generated compressed air has a lower volume and a higher pressure than the compressed natural gas fed to the compression exchange apparatus.

13. (canceled)

14. (canceled)

15. The method of claim 9 wherein the compression exchange apparatus further comprises a second compression cylinder that includes a second piston disposed therein.

16. The method of claim 15 wherein the first inlet and the first outlet are disposed in the first compression cylinder in fluidic communication with a first side of the first piston and the second inlet and the second outlet are disposed in the second compression cylinder in fluidic communication with a first side of the second piston.

17. The method of claim 16 further comprising: a third inlet in fluidic communication with a second side of the first piston to allow compressed natural gas to enter the first compression cylinder on the second side of the first piston;a second inlet in fluidic communication with a second side of the second piston to receive air at a third pressure;a first outlet in fluidic communication with the second side of the first piston for providing decompressed natural gas generated by decompressing the compressed natural gas in the second side a path to escape the first compression cylinder;a second outlet in fluidic communication with the second side of the second piston for providing compressed air at a higher fourth pressure than the air entering the second compression cylinder at the third pressure to exit the second compression cylinder, the second piston in the second compression cylinder to transfer the energy of the compressed natural gas into compressing the air at the third pressure to generate the compressed air at the higher fourth pressure.

18. The method of claim 17 further comprising an oscillating control valve to direct a feed of compressed natural gas alternatingly between the first inlet and the third inlet of the first compression cylinder.

19. The method of claim 17 further comprising a linkage device that is connected on one end to the first piston and connected on a second end to the second piston to transfer movement of the first piston to the second piston and to transfer movement of the second piston to the first piston.

20. The method of claim 9 wherein the compression exchange apparatus operates without combustion.