US-20260125993-A1 - DEVICE FOR ENERGY CONVERSION

US20260125993A1US 20260125993 A1US20260125993 A1US 20260125993A1US-20260125993-A1

Abstract

A device for isothermal expansion and compression of a gas, ensuring the compression of the gas by consuming mechanical energy and the restitution of the mechanical energy by the expansion of the gas. The device includes at least two liquid pistons movable in at least two chambers each including a gas that is able to be compressed or expanded by movement of the liquid pistons. A mechanical actuator, including at least one solid piston, ensures the movement of the liquid pistons in the chambers. Each chamber includes an insert, through which the liquid and the gas can circulate, the insert including through-cells, which extend in a direction parallel to the direction of movement of the liquid piston in the insert. The device includes at least one first phase separator connected to an outlet of each of the chambers, and to a tank for storing pressurized gas.

Inventors

Thibault NEU

Assignees

SEGULA ENGINEERING

Dates

Publication Date: 20260507
Application Date: 20231003
Priority Date: 20221010

Claims (16)

1 . A device for the isothermal expansion and compression of a gas, ensuring the compression of said gas by consuming mechanical energy and the restitution of mechanical energy by the expansion of said gas, said device comprising: at least one first and at least one second liquid piston, movable respectively in a first and a second chamber, each of said at least one first and second chambers comprising a gas, able to be compressed or expanded under the effect of the movement of said at least one first or second liquid piston; an actuator capable of moving said at least one first and second liquid pistons in said first and second chambers; each of said at least one first and second chambers comprising respectively at least one first and at least one second apertured insert through which said liquid and said gas can flow; said actuator is a mechanical actuator comprising at least one solid piston; said apertured insert comprises through-cells, which extend between a first cell opening opening out at one end of said insert and a second cell opening opening out at a second end of said insert, said cells being oriented in a direction which is either parallel to the direction of movement of said liquid piston in said insert or inclined with respect to the direction of movement of said liquid piston; and said device further comprises at least a first phase separator connected to a first outlet of said first chamber and to a second outlet of said second chamber.
2 . The device according to claim 1 , characterized in that said phase separator is connected to a pressurized gas storage tank.
3 . The device according to claim 2 , characterized in that it comprises a second separator, connected to said first and second outlets of said first and second chambers, respectively, in that said first separator comprises a first internal pressure which corresponds to the internal pressure of the gas comprised in said pressurized gas reservoir and in that said second separator comprises a second internal pressure which corresponds to atmospheric pressure.
4 . The device according to claim 3 , characterized in that said first and second separators are in fluid communication with one another to allow liquid to pass from the first separator to the second separator.
5 . The device according to claim 3 , characterized in that it comprises a first air intake device ensuring the passage of air at atmospheric pressure between said at least one first chamber and said second separator and in that it comprises a second air intake device at atmospheric pressure between said at least one second chamber and said second separator.
6 . The device according to claim 3 , characterized in that it comprises a third air intake device ensuring the passage of compressed air between said first chamber and said first separator and in that it comprises a fourth compressed air intake device between said second chamber and said first separator.
7 . The device according to claim 3 , characterized in that it comprises a first low-flow control valve ensuring the passage of fluids from said first separator to said first chamber and in that it comprises a second low-flow control valve ensuring the passage of fluids from said first separator to said second chamber.
8 . The device according to claim 3 , characterized in that it comprises a regulating valve set at a safety pressure between said first chamber and said first separator and/or between said second chamber and said first separator, to enable a volume of liquid to be discharged from said at least one first or second liquid piston to the first separator.
9 . The device according to claim 1 , characterized in that each of the first and second chambers is fluidly connected to a fluid/fluid exchanger which makes it possible to maintain said at least first and second liquid pistons, respectively, at ambient temperature, preferably with a tolerated temperature variation of plus or minus 10° C., said fluid/fluid exchanger preferably comprising a pump, a fluid/air exchanger or a fluid/fluid exchanger, optionally a motorized fan if said exchanger is a fluid/air exchanger and optionally at least one control valve.
10 . The device according to claim 1 , characterized in that the insert comprises a core of structural material comprising an expanded honeycomb structure.
11 . The device according to claim 1 , characterized in that said mechanical actuator comprises a magnetically actuated linear motor.
12 . The device according to claim 1 , characterized in that said mechanical actuator comprises a motor associated with a crankshaft.
13 . The device according to claim 1 , characterized in that said mechanical actuator comprises a motor associated with a worm screw.
14 . An installation comprising at least two devices according to claim 1 , characterized in that said mechanical actuators of said at least two devices are mechanically linked to operate together, and in that it comprises a first phase separator common to said at least two devices, said common first phase separator being connected to a first outlet of the first chambers of the devices and to a second outlet of the second chambers of said devices, said first phase separator being connected to a common pressurized gas storage tank.
15 . The installation according to claim 14 , two comprising a second separator, connected to said first and second outlets of said first and second chambers, respectively, said first separator comprises a first internal pressure which corresponds to the internal pressure of the gas comprised in said pressurized gas reservoir and said second separator comprises a second internal pressure which corresponds to atmospheric pressure, characterized in that said second separator common to said at least two devices, said common second separator being connected to said first and second outlets of said first and second chambers of each of said at least two devices, in that said first common separator comprises a first internal pressure which corresponds to the internal pressure of the gas comprised in said common pressurized gas tank and in that said second separator comprises a second internal pressure which corresponds to atmospheric pressure.
16 . A method for implementing a device according to claim 1 , characterized in that it comprises the following steps: actuating the mechanical actuator, moving said at least one solid piston causing the movement of said first liquid piston in said first chamber and said second liquid piston in said second chamber, said first and second liquid pistons being moved in opposite directions, the first liquid piston compressing said gas in the insert of said first chamber to a first predetermined pressure, the second liquid piston creating a low pressure in said insert of said second chamber to a second pressure, when said first pressure is reached, opening an air intake device between said first chamber and said first phase separator to discharge pressurized gas from the first chamber to said first separator until said liquid piston passes entirely through said insert and reaches the first outlet of the first chamber, and simultaneously the intake of air into said second chamber.

Description

The invention concerns a system for energy conversion and storage. In the literature, gas compression and/or expansion by means of a liquid piston appears to be a promising solution for increasing the energy efficiency of power generation plants, with the aim of achieving the most isothermal thermodynamic evolution possible. Technologies are known, such as those described in patent application FR 3036887, which use pumps or turbines to achieve energy conversion between a mechanical actuator and the liquid in the liquid piston. One or more liquid piston compression stages are implemented in such systems to traverse the desired gas pressure range. Various installations or devices can be deployed to increase heat exchange in the liquid piston compression chamber, such as spraying water droplets, running multiple chambers in parallel, adding a heat exchange insert, etc. These installations give rise to a number of problems: in particular, to achieve near-isothermal compression/expansion, a significant heat exchange is required in the expansion and/or compression chambers, the value of which is several orders of magnitude greater than the exchanges existing in conventional technologies. The installations proposed in patent application FR 3036887 have lengthened compression/expansion times, but use simple technical solutions to achieve near-isothermal operation. As a result, however, the plants are quite large, taking up a lot of space (around 50,000 m3 for a 15 MW power plant), which can lead to high operating costs. Other technologies offer more compact solutions, but are more complex to implement, which means that operating costs cannot be reduced. Thus, the level of complexity and the cost of such installations are obstacles to the development of such technologies. The invention offers an alternative solution that is simple to implement and can be sized to suit the applications for which it will be specifically designed. To this end, the invention relates to a device for the isothermal expansion and compression of a gas, ensuring the compression of said gas by consuming mechanical energy and the restitution of the mechanical energy by the expansion of said gas, said device comprising: at least one first and at least one second liquid piston, movable respectively in a first and a second chamber, each of said at least one first and second chambers comprising a gas that is able to be compressed or expanded by movement of said at least one first or second liquid piston,an actuator, capable of moving said at least first and second liquid pistons in said first and second chambers, each of said at least one first and second chambers respectively comprising at least one first and at least one second apertured insert, through which said liquid and said gas can flow. The device according to the invention is remarkable in that the actuator is a mechanical actuator comprising at least one solid piston, in that said apertured insert comprises through-cells which extend between a first cell aperture opening out at one end of said insert and a second cell aperture opening out at a second end of said insert, said cells being oriented in a direction which is either parallel to the direction of movement of said liquid piston in said insert or inclined with respect to the direction of movement of said liquid piston. Finally, said device further comprises at least a first phase separator connected to a first outlet of said first chamber and to a second outlet of said second chamber. Advantageously, the phase separator is connected to a pressurized gas storage tank. According to an advantageous embodiment, the device according to the invention comprises a second separator, connected to said first and second outlets of said first and second chambers, respectively, in that said first separator comprises a first internal pressure which corresponds to the internal pressure of the gas comprised in said pressurized gas tank and in that said second separator comprises a second internal pressure which corresponds to atmospheric pressure. Preferably, the first and second separators are in fluid communication with one another to allow liquid to pass from the first separator to the second separator. Even more preferably, the device comprises a first air intake device ensuring the passage of air at atmospheric pressure between said at least one first chamber and said second separator, as well as a second air intake device at atmospheric pressure between said at least one second chamber and said second separator. In addition, the device comprises a third air intake device for the passage of compressed air between said first chamber and said first separator, and a fourth air intake device for the passage of compressed air between said second chamber and said first separator. Even more preferably, the device comprises a first low-flow control valve for the passage of fluids from said first separator to said first chamber, and a second low-flow