Gas compression device

Abstract

To provide a gas compression device capable of enhancing specific energy at the time of manufacturing compression gas while actualizing an isothermal compression process for the compressive gas such as air.SOLUTION: A gas compression device 10 using a liquid piston for compressing gas captured into a cylinder tank 1A, includes liquid filling means 6 for filling liquid into the cylinder tank 1A, and heat absorbing means 13A for absorbing compression heat into liquid with direct heat exchange between compression gas which is generated in the cylinder tank 1A and a liquid dispersion flow while changing the liquid filled into the cylinder tank 1A, into the liquid dispersion flow composed of liquid droplets and / or liquid films, the heat absorbing means 13A having a liquid delivery mechanism 53A for delivering the liquid before being changed into the liquid dispersion flow, along the axial line of the cylinder tank 1.SELECTED DRAWING: Figure 1B

Description

Technical Field

[0001] The present invention relates to a gas compression device for compressing gas.

Background Art

[0002] Conventionally, electric air compressors such as screw type, scroll type, rotary vane type, and reciprocating piston type have been widely used. These air compressors are devices that adiabatically compress the inhaled air by a mechanical compression mechanism to produce compressed air at a required pressure. In the mechanical compression mechanism, after a certain operating time elapses, leakage of compressed air occurs due to wear of the gas seal part (specifically, rotor tooth groove part, tip seal, slide vane, piston ring, etc.), and a decrease in volumetric efficiency is likely to occur.

[0003] Also, in the adiabatic compression process, the gas phase part holds the compression heat generated by the increase in the kinetic energy of molecules and becomes high temperature, and the air in the compression process tries to expand against compression. Therefore, in this type of air compressor, the specific energy is directly related to the running cost.

[0004] In view of the characteristics of such a mechanical compression mechanism, a liquid pump type gas compression device disclosed in, for example, Patent Documents 1 and 2 has been studied for a long time.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] A liquid pump type gas compression device has a mechanism that compresses air inside a cylinder tank by sending a liquid (typically water) into the lower part of the cylinder tank into which atmospheric air is taken in, using a liquid pump. That is, the liquid filled inside the cylinder tank serves as a piston, and as the liquid level rises, the compression of the air progresses. The devices disclosed in Patent Documents 1 and 2 have a configuration in which the liquid piston is alternately moved between two cylinder tanks to periodically produce compressed air. And during the production of compressed air, an operation control that continuously drives the liquid pump is adopted.

[0007] In the air compression process, since the contact surface between the cylinder tank corresponding to the cylinder and the liquid piston is completely sealed, there is no leakage of the compressed air, and high volumetric efficiency is maintained. However, continuously driving the liquid pump increases the power consumption, and there is a problem that it is difficult to obtain the expected specific energy.

[0008] Also, since a part of the compression heat generated during the compression process is absorbed by the liquid through the liquid level of the liquid piston, an intermediate compression process between adiabatic compression and isothermal compression (quasi-isothermal compression process) is realized. However, it is far from a complete isothermal compression process, and there is still room for further improvement in terms of specific energy. In view of the above problems, the present invention aims to provide a gas compression device that can realize an isothermal compression process for compressible gases such as air and increase the specific energy during the production of compressed gas.

Means for Solving the Problems

[0009] The gas compression device according to the present invention is a gas compression device that compresses the gas taken into the cylinder tank by a liquid piston, and includes a liquid injection means for injecting a liquid into the cylinder tank, and while changing the liquid injected into the cylinder tank into a liquid dispersion flow composed of liquid droplets and / or a liquid film, heat absorption means for absorbing the compression heat by direct heat exchange between the compressed gas generated in the cylinder tank and the liquid dispersion flow, and the heat absorption means has a liquid delivery mechanism for delivering the liquid before changing into the liquid dispersion flow in a direction along the axis of the cylinder tank. According to this configuration, an isothermal compression process for a compressible gas such as air can be realized, and the specific energy during the production of the compressed gas can be increased.

[0010] More specifically, as the above configuration, the liquid delivery mechanism may include a spray nozzle for spraying the liquid into the cylinder tank, and the spray nozzle may be arranged in the central region of the top plate of the cylinder tank so that the spraying direction is downward. Further, more specifically, as the above configuration, the liquid injection means may include a liquid pump, and the liquid delivery mechanism may be configured to include a liquid introduction line that branches off a part of the liquid being transferred by the liquid pump and guides it to the spray nozzle.

[0011] More specifically, as the above configuration, the liquid delivery mechanism may be configured to include a liquid introduction line that extracts a part of the liquid being filled in the cylinder tank and guides it to the spray nozzle, and an auxiliary pump provided in the liquid introduction line. Further, more specifically, as the above configuration, the liquid delivery mechanism may be configured to include a liquid supply pipe extending along the axis of the cylinder tank from the bottom plate side to the top plate side of the cylinder tank.

[0012] More specifically, as the above configuration, the tip opening of the liquid supply pipe may be opposed to the central region of the top plate. Further, more specifically, as the above configuration, a liquid film formation promoting member may be arranged at the tip opening of the liquid supply pipe.

[0013] More specifically, as the above configuration, the liquid supply pipe may have a plurality of branch pipes that branch out radially in the horizontal direction from the tip end and extend, and the tip end openings of each of the branch pipes may face the top plate. Further, more specifically, as the above configuration, a liquid film formation promoting member may be arranged in the central region of the top plate.

[0014] More specifically, as the above configuration, the liquid supply pipe may have a plurality of branch pipes that branch out radially in the horizontal direction from the tip end and extend, and spray nozzles with a downward spray direction may be attached to each of the branch pipes. Further, more specifically, as the above configuration, a liquid film formation promoting member may be arranged below the spray direction of the spray nozzle. Further, more specifically, as the above configuration, the liquid supply pipe may include a swirling flow generating member made of a plate material that is housed inside at least the tip end region and is subjected to torsional bending processing, and a fine flow generating member made of a mesh material or a fiber material that is attached to the tip end opening.

Advantages of the Invention

[0015] According to the gas compression device of the present invention, an isothermal compression process for a compressible gas such as air can be realized, and the specific energy during the production of the compressed gas can be increased.

Brief Description of the Drawings

[0016]

Figure 1A

Figure 1B

Figure 1C

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Embodiments for Carrying Out the Invention

[0017] Each embodiment of the present invention will be described below with reference to each drawing.

[0018] 1. First Embodiment (1) Device Configuration of Gas Compression Device FIG. 1A is a configuration diagram showing a schematic configuration of a gas compression device 10 according to an embodiment of the present invention. The gas compression device 10 is a liquid pump type gas compression device.

[0019] As shown in FIG. 1A, the gas compression device 10 includes two cylinder tanks 1A and 1B, an intake mechanism 2, and an exhaust mechanism 3. By sending liquid L from the lower parts of the cylinder tanks 1A and 1B respectively, the air (a form of compressible gas) accommodated inside each of the cylinder tanks 1A and 1B can be compressed. Regarding the type of the liquid L, as will be described later, clean water is preferable, but other types of liquids may be used as long as the gist of the present invention is not deviated from.

[0020] The gas compression device 10 is provided with pressure sensors Px for detecting the gas phase pressure inside each of the cylinder tanks 1A and 1B. The air inside the cylinder tank 1A can be discharged by opening the air vent valve 14A as needed, and the air inside the cylinder tank 1B can be discharged by opening the air vent valve 14B as needed.

[0021] The intake mechanism 2 communicates with the upper spaces of the cylinder tanks 1A and 1B, and has an intake line 21A provided corresponding to the cylinder tank 1A and an intake line 21B provided corresponding to the cylinder tank 1B. An intake valve 22A is provided in the intake line 21A, and an intake valve 22B is provided in the intake line 21B.

[0022] The intake valve 22A opens (is in an open state) when the internal pressure of the cylinder tank 1A falls below the first pressure, and closes (is in a closed state) when the internal pressure of the cylinder tank 1A exceeds the second pressure which is equal to or higher than the first pressure. The intake valve 22B opens when the internal pressure of the cylinder tank 1B falls below the first pressure, and closes when the internal pressure of the cylinder tank 1B exceeds the second pressure which is equal to or higher than the first pressure. The intake valves 22A and 22B can be constituted by self-operated valves or automatic valves that operate at the required pressure. In this embodiment, as an example, it is assumed that the intake valves 22A and 22B are constituted by self-operated valves.

[0023] When the intake valves 22A and 22B are self-operated valves, a check valve can be applied as shown in the configuration diagram of Fig. 1A. In this case, the check valve opens when the secondary pressure falls below the first pressure (i.e., when it becomes a negative pressure), and closes when it exceeds the second pressure (i.e., when it becomes a positive pressure).

[0024] When the intake valves 22A and 22B are automatic valves, an electric drive valve (electromagnetic valve or electric valve) can be applied. In this case, the electric drive valve opens when the detected pressure of the pressure sensor Px falls below the first pressure, and closes when it exceeds the second pressure. The first pressure and the second pressure in this case can be set to appropriate values in the control means 7, for example.

[0025] The exhaust mechanism 3 communicates with the upper spaces of the cylinder tanks 1A and 1B. The exhaust mechanism 3 has an exhaust line 31A provided corresponding to the cylinder tank 1A and an exhaust line 31B provided corresponding to the cylinder tank 1B. An exhaust valve 32A is provided in the exhaust line 31A, and an exhaust valve 32B is provided in the exhaust line 31B.

[0026] The exhaust valve 32A is a valve that closes when the internal pressure of the cylinder tank 1A falls below the third pressure and opens when the internal pressure of the cylinder tank 1A exceeds the fourth pressure which is equal to or higher than the third pressure. The exhaust valve 32B is a valve that closes when the internal pressure of the cylinder tank 1B falls below the third pressure and opens when the internal pressure of the cylinder tank 1B exceeds the fourth pressure which is equal to or higher than the third pressure. The exhaust valves 32A and 32B can be constituted by self-operated valves or automatic valves that operate at a required pressure. In this embodiment, as an example, it is assumed that the exhaust valves 32A and 32B are constituted by self-operated valves.

[0027] When the exhaust valves 32A and 32B are self-operated valves, a back pressure valve (primary pressure regulating valve) can be applied as shown in the configuration diagram of FIG. 1A. In this case, the back pressure valve closes when the primary pressure falls below the third pressure (a mechanically adjustable set value) and opens when it exceeds the fourth pressure (a mechanically adjustable set value which can be the same value as the third pressure).

[0028] When the exhaust valves 32A and 32B are automatic valves, an electric drive valve (electromagnetic valve or electric motor-driven valve) can be used. In this case, the electric drive valve opens when the detected pressure of the pressure sensor Px falls below the third pressure and closes when it exceeds the fourth pressure. The third pressure and the fourth pressure in this case can be set to appropriate values in the control means 7, for example.

[0029] Note that when the above-described self-operated valve is used, suction and discharge are actively performed without using electric power, and thus, from this viewpoint, it can contribute to the reduction of specific energy. On the other hand, when the above-described automatic valve is used, by selecting a valve type with a small pressure loss during suction and discharge, power-saving operation with less energy loss becomes possible, and thus, from this viewpoint, it can contribute to the reduction of specific energy.

[0030] At the lower part of the cylinder tank 1A, a first liquid port 11A and a second liquid port 12A are provided. Also, at the lower part of the cylinder tank 1B, a first liquid port 11B and a second liquid port 12B are provided. A first liquid flow line 41A is connected to the first liquid port 11A, and a first liquid flow line 41B is connected to the first liquid port 11B. A second liquid flow line 51A is connected to the second liquid port 12A, and a second liquid flow line 51B is connected to the second liquid port 12B.

[0031] Also, the gas compression device 10 is provided with a liquid pump 6. Further, the gas compression device 10 includes a liquid suction line (suction side common line) 61 that connects the suction side of the liquid pump 6 to the first liquid flow lines 41A and 41B, and a liquid discharge line (discharge side common line) 62 that connects the discharge side of the liquid pump 6 to the second liquid flow lines 51A and 51B.

[0032] A first liquid flow control valve 42A is provided in the first liquid flow line 41A, and a first liquid flow control valve 42B is provided in the first liquid flow line 41B. A second liquid flow control valve 52A is provided in the second liquid flow line 51A, and a second liquid flow control valve 52B is provided in the second liquid flow line 51B.

[0033] When the first liquid flow control valves 42A and 42B corresponding to one of the cylinder tanks 1A and 1B are in an open state and the second liquid flow control valves 52A and 52B corresponding to the other of the cylinder tanks 1A and 1B are in an open state, when the liquid pump 6 is driven, the liquid L is transferred through the first liquid flow lines 41A and 41B corresponding to one of the cylinder tanks 1A and 1B, the liquid suction line 61, the liquid pump 6, the liquid discharge line 62, and the second liquid flow lines 51A and 51B corresponding to the other of the cylinder tanks 1A and 1B. That is, the liquid L is transferred from one of the cylinder tanks 1A and 1B to the other of the cylinder tanks 1A and 1B.

[0034] In addition, a liquid feed check valve 611 is provided in the liquid suction line 61, and a flow sensor Fx (one form of flow detection means) is provided in the liquid discharge line 62. Note that the flow sensor Fx may be provided in the liquid suction line 61 or the liquid pump 6 instead of the liquid discharge line 62. By detecting a predetermined flow rate, the flow sensor Fx can detect the end of the expansion of the air inside the cylinder tanks 1A and 1B in the expansion and intake process described later.

[0035] In the gas compression device 10, instead of using the flow sensor Fx, alternative means may be used. For example, a flow switch (a switch that is on when the set flow rate is reached or exceeded and off when the set flow rate is not reached) or a magnetic sensor (a sensor that detects the rotational speed by attaching a magnet to the drive shaft directly connected to the rotor (such as an impeller or gear) of the liquid pump 6) can be used as an alternative means to the flow sensor Fx.

[0036] In addition, a spray nozzle (injector) 13A for spraying the liquid L into the internal space is provided in the cylinder tank 1A, and a spray nozzle 13B for spraying the liquid L into the internal space is provided in the cylinder tank 1B. Further, in the gas compression device 10, a liquid introduction line 53A that branches from the second liquid flow line 51A on the secondary side of the second liquid flow control valve 52A and guides a part of the liquid being transferred by the liquid pump 6 to the spray nozzle 13A, and a liquid introduction line 53A that branches from the second liquid flow line 51B on the secondary side of the second liquid flow control valve 52B and guides a part of the liquid L being transferred by the liquid pump 6 to the spray nozzle 13B are provided. A liquid introduction control valve 54A is provided in the liquid introduction line 53A, and a liquid introduction control valve 54B is provided in the liquid introduction line 53B.

[0037] In the compression and exhaust process described below, the liquid L is sprayed from the spray nozzle 13A onto the compressed air inside the cylinder tank 1A, and the liquid L is sprayed from the spray nozzle 13B onto the compressed air inside the cylinder tank 1B, thereby realizing an isothermal compression process. The spray nozzles 13A and 13B can use, for example, full-cone nozzles or hollow-cone nozzles, and are installed in the cylinder tanks 1A and 1B so as to be able to spray the liquid L onto the compressed air space of the air.

[0038] Each of the cylinder tanks 1A and 1B is provided with a liquid level detection electrode rod Lx (a form of liquid level detection means). By detecting that the liquid level of the liquid L inside the cylinder tanks 1A and 1B has reached a predetermined liquid level by the liquid level detection electrode rod Lx, the top dead center of the liquid piston in the compression and exhaust process can be detected.

[0039] An air filter 23 is provided on the upstream side of the intake lines 21A and 21B. By means of the air filter 23, it is possible to remove contaminants, bacteria, etc. contained in the air during intake.

[0040] A liquid discharge line 81 and a liquid supply line 83 are connected to the first liquid circulation line 41A. Note that the liquid discharge line 81 and the liquid supply line 83 may be connected to any one of the cylinder tanks 1A and 1B, the second liquid circulation lines 51A and 51B, the liquid suction line 61, and the liquid discharge line 62 instead of the first liquid circulation line 41A. A liquid discharge valve 82 is provided on the liquid discharge line 81, and a liquid supply valve 84 is provided on the liquid supply line 83.

[0041] When water is used as the liquid L in the gas compression device 10, for example, contaminants and bacteria may not be sufficiently removed by the air filter 23, and there is a concern about water quality contamination and the growth of miscellaneous bacteria due to repeated intake air. In this regard, according to the configuration of the present embodiment, it is possible to periodically perform a blowdown of the retained water via the liquid discharge line 81 and the liquid discharge valve 82. Further, after the blowdown, it is also possible to replenish new water via the liquid supply line 83 and the liquid supply valve 84. Thereby, the liquid piston can be kept in a clean state, and clean compressed air without contamination can be supplied to the load equipment.

[0042] An air separator 91 is provided downstream of the exhaust lines 31A and 31B. The compressed air sent out from the exhaust lines 31A and 31B is separated into gas and liquid by the air separator 91 and then accumulated in a reservoir tank (not shown) arranged on the downstream side. The liquid L separated by the air separator 91 is discharged from a drain trap 92 connected to the liquid reservoir portion of the air separator 91.

[0043] The liquid L intermittently discharged from the drain trap 92 is returned to the cylinder tank 1A or the cylinder tank 1B with a lower liquid pressure by utilizing the pressure of the compressed air and the water head pressure in the air separator 91. A liquid return check valve 93A is provided in the line for returning the liquid L from the drain trap 92 to the cylinder tank 1A, and a liquid return check valve 93B is provided in the line for returning the liquid L from the drain trap 92 to the cylinder tank 1B. By installing the liquid return check valves 93A and 93B, the loss of the liquid L in these lines is prevented.

[0044] As described above, a reservoir tank (not shown) for accumulating compressed air is installed downstream of the air separator 91. Thereby, similar to the operation control of a general gas compression device, it is possible to control the operation and stop of the gas compression device 10 according to the internal pressure of the reservoir tank. In the gas compression device 10, it is also possible to omit the installation of the air separator 91 and adopt a configuration in which gas-liquid separation is performed by the reservoir tank. In this configuration, the drain trap 92 can be connected to the bottom of the reservoir tank.

[0045] The configuration around the cylinder tank 1A will be described in more detail. FIG. 1B schematically shows the configuration in a front view around the cylinder tank 1A, and FIG. 1C schematically shows the configuration in a top view around the cylinder tank 1A. Note that the vertical direction shown in these figures coincides with the vertical direction, and the front-rear and left-right directions are merely defined for convenience so as to be orthogonal to the vertical direction. Also, since the configuration around the cylinder tank 1B is basically the same as the configuration around the cylinder tank 1A, the description thereof is omitted here.

[0046] As shown in FIGS. 1B and 1C, the cylinder tank 1A is a vertical pressure vessel centered on the axis X extending vertically. More specifically, the cylinder tank 1A includes a barrel plate 1a formed in a cylindrical shape with the axis X as the central axis, a top plate 1b closing the opening on the upper end side of the barrel plate 1a, and a bottom plate 1c closing the opening on the lower side of the barrel plate 1a. The top plate 1b and the bottom plate 1c are mirror plates. Also, a spray nozzle 13A is arranged in the central region on the inner surface side of the top plate portion 1b in a downward view so that the spray direction is downward.

[0047] The liquid introduction line 53A has a first extension portion 53a, a second extension portion 53b, and a third extension portion 53c. The first extension portion 53a extends vertically on the right side of the cylinder tank 1A, the lower end is connected to the second liquid flow line 51A, and the upper end is located above the top plate portion 1b. The second extension portion 53b extends horizontally so as to connect the upper end of the first extension portion 53a and the upper end of the third extension portion 53c. The third extension portion 53c extends vertically, and the lower end is connected to the spray nozzle 13A.

[0048] Next, the configuration of the main control system of the gas compression device 10 is shown in FIG. 2. As shown in this figure, the gas compression device 10 is provided with control means 7. The control means 7 controls the operation of at least each element of the process switching element group Z shown in FIG. 2 so that the gas compression device 10 operates normally.

[0049] The process switching element group Z includes elements of the liquid pump 6, each valve corresponding to the cylinder tank 1A (the first liquid flow control valve 42A, the second liquid flow control valve 52A, and the liquid introduction control valve 54A), and each valve corresponding to the cylinder tank 1B (the first liquid flow control valve 42B, the second liquid flow control valve 52B, and the liquid introduction control valve 54B). That is, the control means 7 controls the driving and stopping of the liquid pump 6, the opening and closing of each of the first liquid flow control valves 42A and 42B, the opening and closing of each of the second liquid flow control valves 52A and 52B, and the opening and closing of the liquid introduction control valves 54A and 54B.

[0050] (2) Control content Next, the control content of the main operations in the gas compression device 10 will be described. FIG. 3 is an explanatory diagram schematically showing the transition of the control state of the gas compression device 10 (particularly, the control states of the cylinder tanks 1A and 1B). As shown in this figure, for the control state of the gas compression device 10, after passing through the control states A1 to A5 in order, it further passes through the control states B1 to B5 in order and returns to the control state A1, and the same control state is repeated. Note that the control states B1 to B5 are equivalent to the control states A1 to A5 when the control states are reversed between the cylinder tank 1A and the cylinder tank 1B.

[0051] Hereinafter, each of the above-described control states will be described in more detail with reference to FIGS. 4 to 9. For each valve shown in FIGS. 4 to 9, those shown in black indicate the closed state, and those shown in white indicate the open state.

[0052] Figure 4 shows control state A1. Control state A1 is the state when the compression / exhaust process in cylinder tank 1A (the left tank in this figure) is completed and the state when the expansion / intake process in cylinder tank 1B (the right tank in this figure) is completed. Here, liquid pump 6 is stopped, cylinder tank 1A has reached a predetermined upper liquid level (the top dead center of the liquid piston), and cylinder tank 1B has reached the lower liquid level (the bottom dead center of the liquid piston). The exhaust from cylinder tank 1A has ended, and the gas phase part has a pressure of 3rd pressure or less. However, compressible air that is close to the 3rd pressure remains in cylinder tank 1A.

[0053] Figure 5 shows control state A2. The switching from control state A1 to A2 is performed by switching the opening and closing of the first liquid flow control valves 42A, 42B and the second liquid flow control valves 52A, 52B by the control means 7. In control state A2, the expansion / intake process in cylinder tank 1A is started, and the compression / exhaust process in cylinder tank 1B is started. That is, the liquid L is sent out by the expansion of the gas phase part in cylinder tank 1A, and partial compression and cooling of the gas phase part are performed by the intake of the liquid L in cylinder tank 1B.

[0054] With the liquid pump 6 stopped, the transfer of liquid L from cylinder tank 1A to cylinder tank 1B is started. The transfer is performed via the first liquid flow line 41A, the liquid suction line 61, the liquid pump 6, the liquid discharge line 62, and the second liquid flow line 51B. Specifically, the liquid L is sent out by using the expansion of the gas phase part (the expansion of the remaining compressed air) and the head pressure of the liquid phase part in cylinder tank 1A.

[0055] In the cylinder tank 1B, partial compression of the gas phase starts as the liquid level rises. Since the control means 7 controls the liquid introduction control valve 54B to the open state while filling the liquid L from the second liquid port 12B, the liquid L is sprayed from the spray nozzle 13B, and the compressed air in the cylinder tank 1B is cooled. The compression heat generated in the gas phase is absorbed by the sprayed liquid L and merges into the liquid L being filled from the lower part of the cylinder tank 1B. That is, the absorption of the compression heat is performed through both the droplets of the liquid L sprayed from the upper part and the liquid surface of the liquid L filled from the lower part. Also, since the inside of the cylinder tank 1A is at a positive pressure (a pressure state exceeding the second pressure), the intake valve 22A remains closed.

[0056] Figure 6 shows the control state A3. In the control state A3, the expansion of the gas phase in the cylinder tank 1A is completed, the partial compression of the gas phase in the cylinder tank 1B is completed, and the overall compression of the gas phase is started.

[0057] When the detected flow rate by the flow rate sensor Fx drops to a predetermined flow rate, the liquid pump 6 in the stopped state is driven by the control means 7. When the expansion of the compressed air remaining in the cylinder tank 1A ends and the head pressure difference is balanced, the liquid pressure acting on the first liquid port 11A of the cylinder tank 1A (the sum of the air pressure in the gas phase and the head pressure in the liquid phase) and the liquid pressure acting on the second liquid port 12B of the cylinder tank 1B are in a balanced state, so the delivery of the liquid L stops and the compression of the air becomes impossible.

[0058] Therefore, in this embodiment, while the liquid pump 6 is stopped, when the detected flow rate drops to a predetermined flow rate (a set value that is higher by a differential value than the lower limit flow rate value at which air compression becomes impossible), the liquid pump 6 is driven to continue the delivery of the liquid L. As a result, the liquid pump 6 can be driven without delay to produce compressed air. That is, the liquid L flows at a sufficient flow rate with the liquid level in the cylinder tank 1A being higher than the liquid level in the cylinder tank 1B, and the liquid pump 6 is driven in a state where air compression can be performed. As described above, in this embodiment, the stop of the liquid pump 6 is continued until a predetermined time during the expansion of the remaining compressed air, and then the liquid pump 6 is driven.

[0059] In the cylinder tank 1B, the isothermal compression process is continuing due to the cooling of the gas phase part (heat absorption into the aqueous phase part). However, before the driving of the liquid pump 6, as the liquid pressure in the cylinder tank 1A decreases, the spray flow rate from the spray nozzle 13B gradually decreases.

[0060] FIG. 7 shows the control state A4. In the control state A4, intake air is started due to the generation of negative pressure in the cylinder tank 1A, and overall compression and cooling of the gas phase part are performed in the cylinder tank 1B.

[0061] When the driving of the liquid pump 6 is continued, the liquid pressure in the cylinder tank 1A becomes lower than the liquid pressure in the cylinder tank 1B. When the gas phase part in the cylinder tank 1A turns into a negative pressure (a pressure state lower than the first pressure), the intake valve 22A is opened, and external air is taken into the cylinder tank 1A through the air filter 23.

[0062] In the cylinder tank 1B, the isothermal compression process is continuing due to the cooling of the gas phase part. After the driving of the liquid pump 6, the spray flow rate from the spray nozzle 13B recovers. Note that this spray flow rate gradually decreases as the head pressure (suction head of the liquid pump) in the cylinder tank 1A decreases.

[0063] Figure 8 shows control state A5. In control state A5, intake air continues to be drawn in due to the generation of negative pressure in cylinder tank 1A, and exhaust starts in cylinder tank 1B due to the set pressure in the gas phase section being reached.

[0064] When pressure sensor Px detects that the gas phase section of cylinder tank 1B has reached the fourth pressure, control means 7 determines that the isothermal compression process has ended, closes liquid introduction control valve 54B to stop the liquid spray from spray nozzle 13B, and opens exhaust valve 32B to start discharging compressed air. The driving of liquid pump 6 continues for the delivery of compressed air.

[0065] The delivered compressed air is separated into gas and liquid by air separator 91 and then accumulated in a reservoir tank (not shown) arranged on the downstream side. The liquid L separated by air separator 91 is discharged from drain trap 92. The liquid L intermittently discharged from drain trap 92 is returned to the cylinder tank with a lower liquid pressure (here, cylinder tank 1A where the liquid level has dropped and the gas phase section is in equilibrium with atmospheric pressure due to intake air) by utilizing the pressure of the compressed air and the head pressure in air separator 91.

[0066] Note that in order to prevent liquid droplets from being entrained in the compressed air, the closing timing of liquid introduction control valve 54B may be advanced compared to the opening timing of exhaust valve 32B. That is, liquid introduction control valve 54B may be closed at a set pressure lower than the fourth pressure.

[0067] Figure 9 shows control state B1. In control state B1, the expansion / intake process ends in cylinder tank 1A, and the compression / exhaust process ends in cylinder tank 1B.

[0068] In the cylinder tank 1B, when the liquid piston's top dead center (upper limit liquid level) is detected by the liquid level detection electrode rod Lx, the control means 7 stops the liquid pump 6. At this time, the exhaust valve 32B is closed. Instead of this, in the cylinder tank 1B, when the detected pressure of the gas phase part by the pressure sensor Px drops to the third pressure (a set value lower than the differential value from the exhaust start pressure value by the differential value), the control means 7 may stop the liquid pump 6. At this time, the exhaust valve 32B is closed.

[0069] As described above, the compression and exhaust process will be completed. As a result, at the end of this process, compressed air will surely remain in the cylinder tank 1B. As a result, immediately after switching to the expansion and intake process in the cylinder tank 1B, it is possible to send out the liquid L by utilizing the expansion of the gas phase part without driving the liquid pump 6, which contributes to the reduction of specific energy.

[0070] The control state B1 corresponds to the control state A1 (see Fig. 4) when the control states between the cylinder tank 1A and the cylinder tank 1B are reversed. After this, as already described, the control states B2 to B5 (the control states A2 to A5 when the control states between the cylinder tank 1A and the cylinder tank 1B are reversed) are passed through in order and then return to the control state A1, and the same control state will be repeated. During the control states B2 to B5, the expansion and intake process is executed in the cylinder tank 1B, and the compression and exhaust process is executed in the cylinder tank 1A.

[0071] As described above, the control means 7 according to the present embodiment controls the process switching element group Z so that when one cylinder tank (one of 1A and 1B) is in a control state of executing a compression / exhaust process, the other cylinder tank (the other of 1A and 1B) is in a control state of executing an expansion / intake process. Further, in the compression / exhaust process, the control means 7 ends the process by stopping the liquid pump 6 with compressed air remaining in the cylinder tanks 1A and 1B. Furthermore, in the expansion / intake process, the control means 7 continues to stop the liquid pump 6 until a predetermined time during the expansion of the remaining compressed air, and then drives the liquid pump 6. Therefore, according to the gas compression device 10, it is possible to achieve an improvement in specific energy by realizing an operation cycle by intermittently driving the liquid pump 6.

[0072] In the expansion / intake process, with the liquid pump 6 stopped, the liquid L filled in the cylinder tanks 1A and 1B is sent out by utilizing at least the expansion of the gas phase portion, preferably by utilizing the expansion of the gas phase portion and the head pressure of the liquid phase portion. Then, after a predetermined time during the expansion of the gas phase portion, the liquid pump 6 is driven, and external air is inhaled by utilizing the negative pressure of the gas phase portion generated along with the further sending out of the liquid L.

[0073] In the compression / exhaust process, with the liquid pump 6 stopped, partial compression of the gas phase portion is performed by taking in the liquid L. Then, when the liquid pump 6 is driven, overall compression of the gas phase portion is performed by taking in the liquid L further. And when the gas phase portion reaches the set pressure, the generated compressed air is discharged.

[0074] In the compression and exhaust process, the liquid pump 6 is stopped with compressed air remaining in the cylinder tank, thereby ending the process. Therefore, immediately after switching to the expansion and intake process, even if the stop of the liquid pump 6 is continued, the liquid L can be sent out by utilizing the expansion of the gas phase part. As a result, the gas compression device 10 according to the present invention periodically produces compressed air while intermittently driving the liquid pump 6. As a result, the specific energy can be significantly improved compared to the conventional type of device that continuously drives the liquid pump. Further, even if a liquid pump with a high suction and discharge capacity is mounted, an increase in specific energy can be minimized.

[0075] (3) Regarding the liquid injection means and the heat absorption means As described above, the gas compression device 10 of the present embodiment is a device that compresses the air (a form of gas) taken into the cylinder tanks 1A and 1B by a liquid piston, and includes means for injecting the liquid L into the cylinder tanks 1A and 1B (hereinafter, may be conveniently referred to as "liquid injection means Q1"), and means for absorbing the compression heat by the liquid L (hereinafter, may be conveniently referred to as "heat absorption means Q2").

[0076] The liquid injection means Q1 of the present embodiment includes the liquid pump 6, and the liquid L can be injected into the cylinder tanks 1A and 1B by driving the liquid pump 6. The heat absorption means Q2 is means for absorbing the compression heat by the liquid L through direct heat exchange between the compressed air (a form of compressed gas) generated in the cylinder tanks 1A and 1B and the liquid dispersed flow while changing the liquid L injected into the cylinder tanks 1A and 1B into a liquid (hereinafter referred to as "liquid dispersed flow") composed of at least one of liquid droplets and a liquid film.

[0077] Furthermore, the heat absorption means has a liquid delivery mechanism that delivers the liquid L before it changes into a liquid dispersion flow in a direction along the axes of the cylinder tanks 1A and 1B (in this embodiment, the downward direction which is vertically downward). The liquid delivery mechanism of this embodiment includes spray nozzles 13A and 13B that spray the liquid into the cylinder tanks 1A and 1B, and liquid introduction lines 53A and 53B that divert a part of the liquid L being transferred by the liquid pump 6 and guide it to the spray nozzles 13A and 13B.

[0078] The third extension 53c (see Fig. 1b) of the liquid introduction lines 53A and 53B extends in the vertical direction along the axes of the cylinder tanks 1A and 1B, and the lower ends are connected to the spray nozzles 13A and 13B. As a result, the liquid introduction lines 53A and 53B can deliver the liquid L before it changes into a liquid dispersion flow vertically downward and guide it to the spray nozzles 13A and 13B.

[0079] Also, the spray nozzles 13A and 13B can change the liquid L sent from the liquid introduction lines 53A and 53B into fine mist-like droplets (a form of liquid dispersion flow) and discharge them toward the compressed air in the cylinder tanks 1A and 1B. Thereby, it is possible to absorb the compression heat by the liquid L through the direct heat exchange between the compressed air generated in the cylinder tanks 1A and 1B and the liquid dispersion flow.

[0080] Particularly in this embodiment, the spray nozzles 13A and 13B are arranged in the central region of the top plate 1a of the cylinder tanks 1A and 1B so that the spray direction is downward. Therefore, the fine droplets (sprayed liquid L) and the compressed air are in a countercurrent relationship, enabling efficient cooling of the compressed air. Also, since the liquid L can be sprayed from above the cylinder tanks 1A and 1B, the cooling effect can be expected even when the liquid level in the cylinder tanks 1A and 1B is low. Further, since the spray nozzles 13A and 13B are arranged so that the spray direction is downward from the center of the top plate 1a which is a platen, it is difficult for the fine droplets to hit the inner walls of the cylinder tanks 1A and 1B, and it is possible to efficiently bring the droplets into contact with the compressed air.

[0081] Further, in either or both of the cylinder tanks 1A and 1B, a liquid film forming promoting member for promoting the formation of a liquid film by the liquid L may be arranged. As the liquid film forming promoting member, for example, fillers such as Raschig rings, crimped ribbons, glass fibers, sintered beads, and porous blocks can be adopted, but it is not limited thereto, and various structures configured to form the contacted liquid L into a liquid film may be adopted.

[0082] FIG. 10 shows an example in which a liquid film forming promoting member 71 is arranged directly below the spray nozzle 13A in the cylinder tank 1A and at a position closer to the upper side of the cylinder tank 1A. In this example, the liquid film forming promoting member 71 is fixed at a predetermined position using a fixing member 72 attached to the inner wall of the cylinder tank 1A.

[0083] By arranging the liquid film forming promoting member 71 in this way, at least a part of the liquid L sprayed from the spray nozzles 13A and 13B can be changed into a liquid film (a form of liquid dispersion flow). The liquid L that has become a liquid film has a very large surface area and can be efficiently brought into contact with the compressed air in the cylinder tank 1A to promote direct heat exchange.

[0084] Note that the specific forms of the liquid injection means Q1 or the heat absorption means Q2 in each of the cylinder tanks 1A and 1B are not limited to those described above, and various forms can be adopted without departing from the gist of the present invention. Hereinafter, examples of embodiments in which the liquid injection means Q1 or the heat absorption means Q2 are in other forms will be described by giving the second to fifth embodiments.

[0085] 2. Second Embodiment Next, the second embodiment will be described. In the following description, emphasis will be placed on the description of matters different from those of the first embodiment, and the description of matters common to the first embodiment may be omitted. Also, in the following description, mainly the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1A will be described, but the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1B can be the same.

[0086] FIG. 11 schematically shows the cylinder tank 1A of the second embodiment and its surrounding configuration. The liquid delivery mechanism in the second embodiment includes a liquid introduction line 53A that extracts a part of the liquid L being filled in the cylinder tank 1A and guides it to the spray nozzle 13A, and an auxiliary pump 55 provided in the liquid introduction line 53A.

[0087] More specifically, the liquid introduction line 53A has a fourth extension portion 53x. The fourth extension portion 53x extends downward from below the bottom plate 1c in the cylinder tank 1A and further extends to the right from its lower end. An auxiliary pump 55 is provided in the portion extending to the right. In this embodiment, the lower end of the first extension portion 53a is connected to the right end of the fourth extension portion 53x, and a valve 56 for adjusting the flow rate of the liquid L is arranged in the first extension portion 53a.

[0088] Thus, in the second embodiment, when the auxiliary pump 55 is driven, a part of the liquid L being filled in the cylinder tank 1A is extracted from below the bottom plate 1c into the liquid introduction line 53A according to the opening degree of the valve 56 and guided to the spray nozzle 13A. Thereby, the extracted liquid L can be changed into fine mist-like droplets (a form of liquid dispersion flow) and discharged toward the compressed air in the cylinder tank 1A. Also, since the auxiliary pump 55 is used, the liquid L can be guided to the spray nozzle 13A at a constant pressure, and the spray flow rate and the size of the droplets can be stabilized. The auxiliary pump 55 and the valve 56 are controlled so that the spraying of the liquid L from the spray nozzle 13A is appropriate.

[0089] Also, the temperature of the liquid L in the cylinder tank 1A decreases towards the lower side. In the second embodiment, since the liquid L can be extracted from the position where the temperature of the liquid L in the cylinder tank 1A is the lowest, it is possible to efficiently cool the compressed air. Furthermore, since the auxiliary pump 55 is installed below the cylinder tank 1A, the auxiliary pump 55 can always be filled with the liquid L, eliminating the need for air bleeding. Also in the second embodiment, similar to the example shown in FIG. 10, a liquid film formation promoting member for promoting the formation of the liquid film by the liquid L may be arranged.

[0090] 3. Third Embodiment Next, the third embodiment will be described. In the following description, emphasis will be placed on the description of matters different from the first embodiment, and the description of matters common to the first embodiment may be omitted. Also, in the following description, mainly the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1A will be described, but the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1B can be the same.

[0091] FIG. 12 schematically shows the cylinder tank 1A of the third embodiment and its surrounding configuration. The liquid delivery mechanism in the third embodiment includes a liquid supply pipe 53e extending along the axis of the cylinder tank 1A from the bottom plate 1c side to the top plate 1b side of the cylinder tank 1A. Also, the tip opening of the liquid supply pipe 53e faces the central region of the top plate 1b.

[0092] More specifically, the liquid delivery mechanism of the third embodiment consists of an auxiliary line 53d and a liquid supply pipe 53e. The auxiliary line 53d extends horizontally inside the cylinder tank 1A at a position closer to the lower side of the cylinder tank 1A, with one end connected to the second liquid port 12A and the other end located at the center when viewed from above inside the cylinder tank 1. The liquid supply pipe 53e extends upward from the other end of the auxiliary line 53d until the tip reaches near the top plate 1b.

[0093] As a result, the entire amount of the liquid L fed from the second liquid flow line 51A can be guided near the top plate 1b using the liquid supply pipe 53e disposed within the cylinder tank 1A, and discharged from the tip opening of the liquid supply pipe 53e toward the compressed air. In the third embodiment, the installation of the spray nozzle 13A is omitted, and since the tip opening of the liquid supply pipe 53e opens upward, the liquid L is discharged like a water spray. A part of the discharged liquid L contacts the inner wall of the body plate 1a and changes into a liquid film, and flows down along the inner wall. Thereby, while changing the liquid L into a liquid dispersion flow, it is possible to absorb the compression heat into the liquid L by the direct heat exchange between the compressed air generated within the cylinder tank 1A and the liquid dispersion flow.

[0094] Also in the third embodiment, a liquid film formation promoting member for promoting the formation of the liquid film by the liquid L may be arranged. For example, as shown in FIG. 13, a liquid film formation promoting member 71 may be arranged at the tip opening of the liquid supply pipe 53e. Thereby, it becomes possible to efficiently change the liquid L discharged from the tip opening of the liquid supply pipe 53e into a liquid film. As another example, as shown in FIG. 14, a liquid film formation promoting member 71 may be arranged in the central region of the top plate 1b. Thereby, at least a part of the liquid L discharged from the tip opening of the liquid supply pipe 53e can reach the liquid film formation promoting member 71, and it becomes possible to change the liquid L into a liquid film.

[0095] Also, as illustrated in FIG. 15, in the liquid supply pipe 53e, a swirling flow generating member 75 and a fine flow generating member 76 may be provided. The swirling flow generating member 75 is a member made of a plate material subjected to a twisting and bending process, and is a member that generates a swirling flow of the liquid L. The swirling flow generating member 75 is accommodated inside at least the tip region (the region near the upper end) of the liquid supply pipe 53e.

[0096] The micro-flow generating member 76 is a member made of a mesh material or a fibrous material, and is a member that finely breaks up the water flow of the liquid L to generate micro-flows. The micro-flow generating member 76 is provided at the tip of the liquid supply pipe 53e. As the mesh material here, for example, materials such as woven wire mesh (plain weave type, twill weave type) and punched wire mesh (punching metal) are applicable, and it may be provided by welding to the tip of the liquid supply pipe 53e. As the fibrous material, materials such as steel wool are applicable.

[0097] By providing the swirling flow generating member 75 and the micro-flow generating member 76, the liquid L can be strongly applied to the micro-flow generating member 76 after enhancing the momentum as a swirling flow. As a result, it is possible to efficiently generate micro-flows (a form of liquid dispersion flow) of the liquid L and realize direct heat exchange with compressed air.

[0098] 4. Fourth Embodiment Next, the fourth embodiment will be described. In the following description, emphasis will be placed on the description of matters different from the third embodiment, and the description of matters common to the third embodiment may be omitted. Also, in the following description, mainly the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1A will be described, but the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1B can be made the same.

[0099] FIG. 16 schematically shows the cylinder tank 1A of the fourth embodiment and the surrounding configuration. The liquid supply pipe 53e in the fourth embodiment has a plurality of branch pipes 53f that branch and extend radially in the horizontal direction from the tip, and spray nozzles 13a with a downward spray direction are attached to each of the branch pipes 53f. Each of the branch pipes 53f has the same shape and size, extends in the horizontal direction from the tip of the liquid supply pipe 53e, and extends slightly downward from the horizontal end, and the spray nozzle 13a is attached to the end thereof.

[0100] In the example shown in FIG. 16, two branch pipes 53f branching to the left and right are illustrated, but it is preferable that three or more branch pipes 53f are provided so as to extend radially in the horizontal direction. Further, in order to spray the liquid L evenly, it is preferable that the angles formed by adjacent branch pipes 53f in a top view are equal in all the branch pipes 53f.

[0101] Also, in the fourth embodiment, a liquid film formation promoting member for promoting the formation of the liquid film by the liquid L may be arranged. FIG. 17 shows an example in which the liquid film formation promoting member 71 is arranged so as to cover the positions directly below all the spray nozzles 13A at a position closer to the upper side of the cylinder tank 1A. In this example, the liquid film formation promoting member 71 is fixed at a predetermined position so as to be attached to the liquid supply pipe 53e.

[0102] 5. Fifth Embodiment Next, the fifth embodiment will be described. In the following description, emphasis will be placed on the description of matters different from the third embodiment, and the description of matters common to the third embodiment may be omitted. Also, in the following description, mainly the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1A will be described, but the liquid injection means Q1 and the heat absorption means Q2 of the cylinder tank 1B can be made the same.

[0103] FIG. 18 schematically shows the cylinder tank 1A of the fifth embodiment and its peripheral configuration. The liquid supply pipe 53e in the fifth embodiment has a plurality of branch pipes 53f that branch and extend radially in the horizontal direction from the tip, and the tip openings of the respective branch pipes 53f are opposed to the top plate 1b. Each of the branch pipes 53f has the same shape and size, extends in the horizontal direction from the tip of the liquid supply pipe 53e, and extends slightly upward from the horizontal end, and its end (tip opening) opens upward.

[0104] In the example shown in Fig. 18, two branch pipes 53f branching to the left and right are illustrated, but it is preferable that three or more branch pipes 53f are provided so as to extend radially in the horizontal direction. Further, in order to discharge the liquid L evenly, it is preferable that the angles formed by adjacent branch pipes 53f in a top view are equal in all the branch pipes 53f.

[0105] Also, in the fifth embodiment, a liquid film forming promoting member for promoting the formation of the liquid film by the liquid L may be arranged. For example, as shown in Fig. 19, the liquid film forming promoting member 71 may be arranged in the central region of the top plate 1b. Thereby, at least a part of the liquid L discharged from the tip openings of the respective branch pipes 53f can reach the liquid film forming promoting member 71, and the liquid L can be changed into a liquid film.

[0106] 6. Others (1) Regarding the cooling means It is desirable to provide the gas compression device 10 with a cooling means for promoting heat dissipation from the liquid piston. In this case, for example, a cooling heat exchanger may be provided in the liquid discharge line 62. The cooling heat exchanger is connected to a cooling tower via a cooling water circulation circuit, and cools the liquid L discharged from the liquid pump 6 by heat exchange with the cooling water. When the ambient temperature around the gas compression device 10 becomes higher than the liquid temperature during operation, for example, in summer, there is a risk that compression heat accumulates in the liquid piston. However, by operating the circulation pump provided in the circulation circuit, the liquid piston can be kept below the ambient temperature, and an effect of reducing the specific energy can be obtained.

[0107] (2) Regarding the working medium As the above-described liquid L, that is, the working medium for the liquid piston in the gas compression device 10, for example, clean water (preferably, pure water (RO water, ion-exchanged water) or softened water) is suitable. Since the specific heat capacity of water is very large compared to other substances, it is particularly suitable as a working medium for an isothermal compression process involving absorption of compression heat. Further, since clean water is harmless to the human body, it is also suitable as a working medium for a gas compression device for a food factory.

[0108] In this embodiment, the air inlet of the device is equipped with an air filter 23. However, pollutants and bacteria floating in the air may pass through, and depending on the installation environment of the device, water quality pollution and the growth of miscellaneous bacteria due to repeated intake of air may be a concern. Therefore, it is desirable to perform regular blowdown using the liquid discharge valve 82 and replenish clean water using the liquid supply valve 84.

[0109] Also, as the working medium, for example, brine (aqueous calcium chloride solution, aqueous sodium chloride solution, etc.), aqueous glycerin solution, aqueous ethylene glycol solution, liquid paraffin, vegetable oil, and synthetic oil can be preferably used as antifreeze for cold regions. As the working medium of the gas compression device 10 for food factories, any one of brine, aqueous glycerin solution, liquid paraffin, and vegetable oil is preferable.

[0110] Also, in cold regions, there is a concern about the freezing of water during the stoppage of the gas compression device 10 in winter. Therefore, from the perspective of minimizing this problem, it is desirable to take the following measures. First, as the first measure, regarding the type of the liquid L, even when using clean water in summer and intermediate seasons, it is desirable to replace it with an antifreeze such as the above-mentioned brine in winter. When using such an antifreeze, the installation of the heater and heat insulation material described below is basically unnecessary.

[0111] Also, as the second measure, it is desirable to enclose the entire device with a casing and attach a surface heater to the inner surface of the casing panel. In this case, for example, when the internal temperature of the casing drops below the set temperature, the heater can be energized for heating.

[0112] Furthermore, as the third measure, it is desirable to cover the line through which the liquid L flows in the gas compression device 10 and the liquid pump 6 with a heat insulation material (thermal insulation material), and attach a surface heater to the outer surfaces of the cylinder tanks 1A and 1B. In this case, for example, when the ambient temperature around the cylinder tanks 1A and 1B drops below the set temperature, the heater can be energized for heating.

[0113] (3) Regarding the basic number of cylinder tanks In the above-described embodiment, the basic number of cylinder tanks in the gas compression device was set to 2. However, the basic number of cylinder tanks can be set to 3, and three processes including the standby process can be rotated. The significance of this configuration is that during regular replacement or maintenance of the working medium, one of the cylinders in the standby process can be put into a standby state, and the production of compressed air can be continued with the remaining two cylinders. In this case, the operating modes of the gas compression device having three cylinder tanks (for convenience, referred to as the first to third tanks) are sequentially switched among three patterns of the first to third operating modes.

[0114] In the first operating mode, the first tank becomes the expansion / intake process (compression / exhaust process), the second tank becomes the compression / exhaust process (expansion / intake process), and the third tank becomes the standby process. In the second operating mode, the first tank becomes the standby process, the second tank becomes the expansion / intake process (compression / exhaust process), and the third tank becomes the compression / exhaust process (expansion / intake process). In the third operating mode, the first tank becomes the compression / exhaust process (expansion / intake process), the second tank becomes the standby process, and the third tank becomes the expansion / intake process (compression / exhaust process).

[0115] It is also possible to set the basic number of cylinder tanks to 4 or more. However, for example, when the basic number of cylinder tanks is set to 4, it is usually more desirable to install two gas compression devices each equipped with two cylinder tanks to double the production amount of compressed air per unit time, rather than installing four cylinder tanks in one gas compression device.

[0116] 7. Effects, etc. As described above, the gas compression device 10 of each embodiment is a device that compresses a compressible gas taken into the cylinder tanks 1A and 1B by a liquid piston, and includes a liquid injection means Q1 (means for injecting a liquid L into the cylinder tanks 1A and 1B) and a heat absorption means Q2 (while changing the liquid L injected into the cylinder tanks 1A and 1B into a liquid dispersion flow composed of liquid droplets and / or a liquid film, by direct heat exchange between the compressed gas generated in the cylinder tanks 1A and 1B and the liquid dispersion flow, means for absorbing the compression heat by the liquid L). Further, in the gas compression device 10, the heat absorption means Q2 has a liquid delivery mechanism that delivers the liquid L before it changes into a liquid dispersion flow in a direction along the axis of the cylinder tanks 1A and 1B).

[0117] Therefore, according to the gas compression device 10 of each embodiment, since the compression heat is quickly absorbed by the liquid piston through the liquid dispersion flow, an isothermal compression process for the compressible gas can be realized, and it is possible to increase the specific energy during the production of the compressed gas. In addition, by providing a liquid delivery mechanism that delivers the liquid L before it changes into a liquid dispersion flow in a direction along the axis of the cylinder tanks 1A and 1B, the liquid L can be evenly delivered from the center of the cylinder tanks 1A and 1B in the circumferential direction, and it is possible to increase the heat exchange efficiency between the liquid dispersion flow and the compressed gas.

[0118] The embodiments of the present invention have been described above, but the configuration of the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the invention. That is, the above embodiments should be considered as illustrative in all respects and not restrictive. The technical scope of the present invention is shown not by the description of the above embodiments but by the scope of the claims, and it should be understood that all modifications belonging to the meaning and scope equivalent to the scope of the claims are included.

Industrial Applicability

[0119] The present invention can be used in a gas compression device for compressing a gas.

[0120] <Contribution to the Sustainable Development Goals (SDGs) Led by the United Nations> The air compressor according to the present disclosure improves specific energy by realizing an isothermal compression process and can contribute to the achievement of Goal 7, "Affordable and Clean Energy," of the SDGs (Sustainable Development Goals).

Description of Signs

[0121] 1A, 1B Cylinder tank 1a Barrel plate 1b Top plate 1c Bottom plate 2 Intake mechanism 3 Exhaust mechanism 6 Liquid pump 7 Control means 10 Gas compression device 11A, 11B First liquid port 12A, 12B Second liquid port 13A, 13B Spray nozzles 14A, 14B Air vent valve 21A, 21B Intake line 22A, 22B Intake valve 23 Air filter 31A, 31B Exhaust line 32A, 32B Exhaust valve 41A, 41B First liquid flow line 42A, 42B First liquid flow control valve 51A, 51B Second liquid flow line 52A, 52B Second liquid flow control valve 53A, 53B Liquid introduction line 53a First extension 53b Second extension 53c Third extension 53d Auxiliary line 53e Liquid supply pipe 53x Fourth extension 53f Branch pipe 54A, 54B Liquid introduction control valve 55 Auxiliary pump 56 Valve 61 Liquid suction line 62 Liquid discharge line 71 Liquid film formation promoting member 72 Fixing member 75 Swirling flow generating member 76 Micro-flow generating member 81 Liquid discharge line 82 Liquid discharge valve 83 Liquid supply line 84 Liquid supply valve 91 Air separator 92 Drain trap 93A, 93B Return liquid check valve 611 Liquid feeding check valve Fx Flow rate sensor Lx Liquid level detection electrode rod Px Pressure sensor L Liquid Z Process switching element group

Claims

1. A gas compression device that compresses gas taken into a cylinder tank by a liquid piston, comprising: liquid injection means for injecting liquid into the cylinder tank; heat absorption means for absorbing compression heat by direct heat exchange between the compressed gas generated in the cylinder tank and the liquid dispersed flow while changing the liquid injected into the cylinder tank into a liquid dispersed flow composed of liquid droplets and / or a liquid film; The heat absorption means is a gas compression device having a liquid delivery mechanism for delivering the liquid before changing into the liquid dispersed flow in a direction along the axis of the cylinder tank.

2. The liquid delivery mechanism includes a spray nozzle for spraying the liquid into the cylinder tank, The spray nozzle is arranged in a central region of the top plate of the cylinder tank so that the spraying direction is downward. The gas compression device according to claim 1.

3. The liquid injection means includes a liquid pump, The liquid delivery mechanism includes a liquid introduction line for diverting a part of the liquid being transferred by the liquid pump and guiding it to the spray nozzle. The gas compression device according to claim 2.

4. The liquid delivery mechanism, includes a liquid introduction line for extracting a part of the liquid being filled in the cylinder tank and guiding it to the spray nozzle, and an auxiliary pump provided in the liquid introduction line. The gas compression device according to claim 2.

5. The liquid delivery mechanism includes a liquid supply pipe extending along the axis of the cylinder tank from the bottom plate side to the top plate side of the cylinder tank. The gas compression device according to claim 1.

6. The gas compression device according to claim 5, wherein the tip opening of the liquid supply pipe faces the central region of the top plate.

7. The gas compression device according to claim 6, wherein a liquid film formation promoting member is arranged at the tip opening of the liquid supply pipe.

8. The liquid supply pipe has a plurality of branch pipes radially extending in the horizontal direction from the tip, The gas compression device according to claim 5, wherein the tip opening of each of the branch pipes faces the top plate.

9. The gas compression device according to claim 6 or claim 8, wherein a liquid film formation promoting member is arranged in the central region of the top plate.

10. The liquid supply pipe has a plurality of branch pipes radially extending in the horizontal direction from the tip, The gas compression device according to claim 5, wherein a spray nozzle with a downward spraying direction is attached to each of the branch pipes.

11. The gas compression device according to any one of claims 2 to 4 and 10, wherein a liquid film formation promoting member is disposed below the spraying direction of the spray nozzle.

12. The liquid supply pipe comprises a swirling flow generating member made of a plate material that is housed at least inside the tip region and subjected to torsional bending processing, and a fine flow generating member made of a mesh material or a fiber material that is attached to the tip opening, the gas compression device according to claim 5.

Images