JP6998052B2 - Heat exchanger - Google Patents

Description

The present invention relates to a heat exchanger configured to be capable of cooling a gas by heat exchange between a gas compressed by a multi-stage compressor that compresses the gas to be processed in multiple stages and a cooling fluid.

For example, in a hydrogen gas station that supplies hydrogen gas to an air supply target such as a hydrogen gas fuel cell vehicle, a sufficient amount of hydrogen gas is supplied to the air supply target in a short time and efficiently. The hydrogen gas to be concerned is stored in a compressed state.

Specifically, in both the on-site type hydrogen gas station and the off-site type hydrogen gas station, a hydrogen gas tank (accumulator) for storing the hydrogen gas supplied to the air supply target via the dispenser. By compressing the hydrogen gas from the hydrogen gas source with a compressor when transferring the hydrogen gas to the hydrogen gas source, it becomes possible to store the high-pressure hydrogen gas in the hydrogen gas tank. In this case, it is difficult to compress the hydrogen gas at one time to a sufficiently high pressure suitable for supplying air from the hydrogen gas tank to the air supply target. Therefore, as the compression device, a multi-stage compression device that gradually compresses hydrogen gas by a plurality of compression strokes is used.

For example, in the compressor unit (hydrogen compressor system) disclosed in the following patent document, hydrogen gas supplied from a hydrogen gas source such as a reformer or a gas cylinder is gradually compressed to an arbitrary pressure ( A configuration is adopted in which air is sent to the accumulator unit in a state of boosting). This compressor unit has a crankshaft connected to the output shaft of the motor, five piston shafts from the first stage piston shaft to the fifth stage piston shaft attached to the crankshaft, and each piston shaft can be stroked. It is provided with five cylinders from the first-stage cylinder to the fifth-stage cylinder housed, and is configured to be able to compress (pressurize) hydrogen gas in five stages. In the following description, the component composed of the piston shaft and the cylinder is also referred to as a “compression element”.

In this case, the temperature of the compressed hydrogen gas rises during adiabatic compression by each compression element. In addition, the high-temperature compressed gas reduces its compression efficiency and may cause malfunction of the compression element. Therefore, in this compressor unit, 4 from the first-stage intercooler to the fourth-stage intercooler 4 for lowering the temperature of the hydrogen gas that has been compressed by each compression element before performing compression by the next compression stroke. It has two intercoolers. Further, this compressor unit is provided with an aftercooler that cools the hydrogen gas compressed by the compression element of the fifth stage before supplying air to the accumulator unit (cools the hydrogen gas after the completion of the multi-stage compression stroke). .. As a result, in this compressor unit, the hydrogen gas stored in the accumulator unit can be suitably boosted to a sufficiently high pressure suitable for supply air.

JP-A-2007-263245 (Page 5-8, Fig. 1-2)

However, the compressor unit disclosed in the above patent document has the following problems. Specifically, in the above compressor unit, each time the compression stroke by each compression element is completed, the hydrogen gas whose temperature has risen due to adiabatic compression is referred to as an intercooler or an aftercooler (hereinafter, also collectively referred to as "cooler"). The configuration that cools by is adopted. In this case, although not explicitly stated in the above patent document, in this type of compression device, a configuration is adopted in which a separate and independent cooler is connected to each compression element to cool hydrogen gas. That is, the compressor unit of the five-stage compression disclosed in the above patent document is configured to include five coolers. Therefore, the compressor unit disclosed in the above patent document has a problem that the occupied space of the entire unit is increased by the space for installing a plurality of coolers (heat exchangers). ..

In addition, since the temperature of hydrogen gas becomes very high during adiabatic compression by this type of compression device, a very large cooler is required to sufficiently cool the hydrogen gas by heat exchange with the atmosphere. .. Further, in a large cooler, the pressure loss when passing through the cooler becomes large due to the long flow path length of the hydrogen gas. Therefore, in this type of compression device, a configuration is adopted in which hydrogen gas is efficiently cooled by heat exchange with a cooling fluid (water or the like). Therefore, in a compressor unit equipped with a plurality of independent coolers (heat exchangers) for each compression element, the piping for supplying the cooling fluid to each cooler and the cooling fluid are recovered from each cooler. Since the number of pipes to be connected is also multiple, there is a problem that the occupied space of the entire unit is further increased.

Furthermore, in a compressor unit equipped with a plurality of independent coolers for each compression element, the number of coolers to be installed at the time of construction is large, and the number of pipes to be connected to each cooler is also large. There is also a problem that the installation work is complicated and it is difficult to reduce the introduction cost of the cooling device.

On the other hand, although not specifically described in the above patent document, when the hydrogen gas is compressed stepwise, the hydrogen gas compressed by the compression stroke on the front stage side has a lower compression ratio, so that the hydrogen gas on the rear stage side has a lower compression ratio. The volume is larger than the hydrogen gas compressed by the compression stroke. For example, when passing through a pipe with the same cross-sectional opening area, the flow velocity of the hydrogen gas compressed by the compression stroke on the front stage side is the compression on the rear stage side. It tends to be faster than the flow velocity in the pipe of hydrogen gas compressed by the stroke. Further, it is known that the faster the flow velocity, the larger the passing resistance and the larger the pressure loss when the pipe is passed through the pipe having the same cross-sectional opening area.

Therefore, in a device that compresses hydrogen gas in multiple stages and devices around it, it is necessary to optimize the cross-sectional opening area and flow path length of the pipe through which the hydrogen gas passes, in consideration of the influence of pressure loss. For this reason, in a compressor unit provided with a plurality of independent coolers for each compression element, it is necessary to make the cross-sectional opening area and the flow path length of the pipes in each cooler different from each other. It is difficult to match the size (external size). Therefore, in the compressor unit disclosed in the above patent document, there is a problem that the installation work of each cooler becomes more complicated as compared with the configuration in which a plurality of coolers of the same size and the same shape are installed. There is.

The present invention has been made in view of the above problems, and the pressure loss generated during cooling of the hydrogen gas compressed by the multi-stage compressor is sufficiently suppressed, and the space occupied by the equipment required for cooling is sufficiently suppressed. The main purpose is to provide a heat exchanger that can be made smaller and the introduction cost can be sufficiently reduced.

In order to achieve the above object, the heat exchanger according to claim 1 is configured to be connectable to a multi-stage compressor that compresses the gas to be processed in multiple stages, and is for cooling with the gas compressed by the multi-stage compressor. A heat exchanger configured to be able to cool the gas by heat exchange with the fluid, and the gas compressed by the Ma-stage compression stroke (Ma is a natural number) in the multi-stage compression device is used as the cooling fluid. The Nth heat exchange that exchanges heat with the cooling fluid from the first heat exchange unit that exchanges heat with the gas compressed by the Mb stage compression stroke (Mb is a natural number of (Ma + 1) or more) in the multi-stage compression device. N heat exchange units up to a unit (N is a natural number of 2 or more and Mb or less), a fluid introduction unit capable of introducing the cooling fluid, and a fluid discharge unit capable of discharging the cooling gas are provided. Each of the heat exchange units includes a container body containing the N heat exchange units, and each heat exchange unit includes a heat transfer coil in which a tube body through which the gas can pass is spirally wound. The tube of each heat transfer coil is made of the same material, and the gas is compressed by the L-stage compression stroke (L is each natural number of Ma or more (Mb-1) or less) in the multi-stage compression device. The cross-sectional opening area of the tubular body in the heat transfer coil of the heat exchange unit that exchanges heat with the cooling fluid is compressed by the compression stroke on the rear side of the L-stage compression stroke in the multi-stage compressor. The cross-sectional opening area of the tube in the heat transfer coil of the heat exchange section for heat exchange of gas with the cooling fluid is equal to or larger than the cross-sectional opening area of the tube in the heat transfer coil of the first heat exchange section. Is formed so as to be at least larger than the cross-sectional opening area of the tubular body in the heat transfer coil of the Nth heat exchange section, and the Kth stage compression stroke (K is (Ma + 1) or more Mb in the multi-stage compression device. The thickness of the tube in the heat transfer coil of the heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by each of the following natural numbers) is the compression stroke on the pre-stage side of the K-stage compression stroke. The thickness of the tube in the heat transfer coil of the heat exchange section for heat exchange of the gas compressed by the gas with the cooling fluid, and the thickness of the tube in the heat transfer coil of the Nth heat exchange section. The thickness is formed so as to be at least thicker than the thickness of the tube in the heat transfer coil of the first heat exchange section, and at least one of the heat exchange sections is inside the container. The heat transfer coil is provided with a plurality of heat transfer coils connected in parallel via a branching / merging metal fitting .

The heat exchanger according to claim 2 is configured to be capable of cooling hydrogen gas as the gas in the heat exchanger according to claim 1 .

In the heat exchanger according to claim 1, the N heat exchange units housed in the container each include a heat transfer coil in which a tube through which gas can pass is spirally wound, and multi-stage compression is performed. The cross-sectional opening area of the tube in the heat transfer coil of the heat exchange section that exchanges heat with the cooling fluid for the gas compressed by the L-stage compression stroke in the device is compressed by the compression stroke on the rear side of the L-stage compression stroke. The cross-sectional opening area of the tube in the heat transfer coil of the heat exchange section that exchanges heat with the cooling fluid is equal to or larger than the cross-sectional opening area of the tube in the heat transfer coil of the first heat exchange section, and the cross-sectional opening area of the tube is at least Nth heat exchange. Each is formed so as to be larger than the cross-sectional opening area of the tube body in the heat transfer coil of the portion.

Therefore, according to the heat exchanger according to claim 1, N heat exchange portions for cooling the gas to be processed in each N-step compression stroke are housed in the container and integrated, thereby separately. Compared with the configuration in which the gas to be processed is cooled in each N-step compression stroke by N independent heat exchangers (coolers), the space occupied by the equipment required for cooling the gas is sufficiently reduced. be able to. Further, since the number of cooling fluid pipes can be reduced, the installation work can be facilitated and the introduction cost can be reduced. Further, by optimizing the cross-sectional opening area of the heat transfer coil constituting each heat exchange section, the pressure loss at the time of cooling the gas can be sufficiently suppressed.

Further, in the heat exchanger according to claim 1 , the tube of each heat transfer coil in each heat exchange section is made of the same material, and the gas compressed by the K-stage compression stroke in the multi-stage compressor is used for cooling. The thickness of the tube in the heat transfer coil of the heat exchange section that exchanges heat with the fluid is the heat transfer of the heat exchange section that exchanges heat with the cooling fluid the gas compressed by the compression stroke on the side before the K-stage compression stroke. Each is formed so as to be equal to or larger than the thickness of the tube in the coil and the thickness of the tube in the heat transfer coil of the Nth heat exchange section is at least thicker than the thickness of the tube in the heat transfer coil of the first heat exchange section. There is.

Therefore, according to the heat exchanger according to claim 1 , the heat exchanger that cools the gas after the compression stroke on the rear stage side where the pressure of the gas to be processed is high is deformed or damaged (gas leakage). For the heat exchange part that cools the gas after the compression stroke on the front stage side where the pressure is not so high, while forming the heat transfer coil with a tube body of sufficient thickness that does not cause By forming the heat coil, the heat transfer coil can be easily manufactured, and the material cost can be reduced, so that the manufacturing cost of the heat exchanger can be sufficiently reduced.

Further, according to the heat exchanger according to claim 1 , pressure loss can be suppressed by configuring at least one of the heat exchange units with a plurality of heat transfer coils connected in parallel. When a heat transfer coil formed of a thick tube is adopted in order to obtain a sufficiently wide cross-sectional opening area, it is difficult to manufacture the heat transfer coil (bending of the tube, etc.), whereas there are a plurality of heat transfer coils. By connecting the heat transfer coils in parallel to obtain the required cross-sectional opening area, a thin tube can be used as the tube of each heat transfer coil, and as a result, the heat transfer coil can be easily manufactured. The manufacturing cost of the heat exchanger can be sufficiently reduced. Further, even if the same tube body is used as the tube body constituting the heat transfer coil in the plurality of heat exchange sections, the cross-sectional opening area can be different, so that the heat transfer section of the plurality of heat exchange sections can be different in the same tube body. When the coil is manufactured, the material cost, that is, the manufacturing cost of the heat exchanger can be further reduced by the amount that the number of types of pipes used is small.

Further, according to the heat exchanger according to claim 2 , by configuring hydrogen gas as a gas to be coolable, equipment such as a hydrogen gas station for supplying hydrogen gas to a hydrogen gas fuel cell vehicle or the like is installed. The heat exchanger can be installed even in a place where the available space is narrow, whereby the hydrogen gas compressed by the multi-stage compressor can be suitably cooled.

It is a block diagram which shows the structure of the hydrogen gas supply system 100. It is a block diagram which shows the structure of the multistage compression device 1 and the heat exchanger 5 for cooling hydrogen gas in a hydrogen gas supply system 100. It is explanatory drawing for demonstrating the structure of the heat exchanger 5 for cooling hydrogen gas in a hydrogen gas supply system 100.

Hereinafter, embodiments of the heat exchanger will be described with reference to the accompanying drawings.

The hydrogen gas air supply system 100 shown in FIG. 1 is, for example, for a hydrogen gas station that supplies hydrogen gas, which is an example of a “gas to be processed”, to an air supply target X2 such as a hydrogen gas fuel cell vehicle. Hydrogen gas that is a facility and is generated in a separate location and transported in a state of being filled in a gas tank for transportation (not shown), or a hydrogen gas generator (not shown) at the installation location of the hydrogen gas air supply system 100. ) Is configured to be able to store hydrogen gas and the like, and the stored hydrogen gas is configured to be able to supply air to the air supply target X2. Specifically, the hydrogen gas air supply system 100 includes a multi-stage compression device 1, a gas tank 2, a dispenser 3, a cooling tower 4, and the like. In the following description, the above-mentioned "gas tank for transportation" and "hydrogen gas generator" are collectively referred to as a hydrogen gas source X1.

The multi-stage compression device 1 is an example of a “multi-stage compression device”, and supplies hydrogen gas supplied from a hydrogen gas source X1 via a hydrogen gas pipe 20 to a gas supply target X2 when the hydrogen gas is stored in the gas tank 2. It is configured to be able to compress the hydrogen gas to a sufficient pressure suitable for the mind. Specifically, as shown in FIG. 2, the multi-stage compressor 1 in the hydrogen gas air supply system 100 of this example is, as an example, a first-stage compressor 11, a second-stage compressor 12, and a third-stage compressor. It is equipped with five "compressors" of 13, a fourth-stage compressor 14, and a fifth-stage compressor 15, and is configured to be capable of multi-stage compression of hydrogen gas from the hydrogen gas source X1 in five stages.

In the multi-stage compressor 1 of this example, the first-stage compressor 11 corresponds to a compressor that performs compression in the "Ma = 1-stage compression stroke", and the fifth-stage compressor 15 has "Mb = 5". It corresponds to a compressor that performs compression in the "stage compression process". Further, although the actual multi-stage compressor 1 includes various components other than the above-mentioned compressors 11 to 15, the multi-stage compressor 1 is used to facilitate understanding of the hydrogen gas air supply system 100. The illustration and description of the components other than the compressors 11 to 15 in the above will be omitted.

In this case, in the hydrogen gas air supply system 100 of this example, as will be described later, each time the compression stroke by each of the compressors 11 to 15 of the multi-stage compressor 1 is completed, the hydrogen gas whose temperature has risen due to adiabatic compression is cooled by hydrogen gas. A configuration for cooling is adopted in the heat exchanger 5. The gas tank 2 is configured to be able to store a sufficient amount of hydrogen gas necessary for supplying air to the air supply target X2, and is configured to be able to maintain the pressure applied to the hydrogen gas by the multi-stage compression device 1. It is a capacitive pressure vessel, and as shown in FIG. 1, it is connected to a heat exchanger 5 for cooling hydrogen gas via a hydrogen gas pipe 25b described later.

The dispenser 3 is connected to the gas tank 2 via the hydrogen gas pipe 26, and can supply hydrogen gas stored in the gas tank 2 to the air supply target X2 connected via the hydrogen gas pipe 27. Has been done. In the actual hydrogen gas air supply system 100, the hydrogen gas is cooled by the dispenser 3 at the time of air supply to the air supply target X2. However, in order to facilitate the understanding of the configuration of the hydrogen gas air supply system 100, the dispenser 3 is used. The illustration and description of the components for cooling the hydrogen gas in the above are omitted.

The cooling tower 4 is a cooling water supply source capable of supplying cooling water W to various facilities of the hydrogen gas air supply system 100, and in the hydrogen gas air supply system 100 of this example, cooling as a "cooling fluid". A configuration is adopted in which water W is supplied from the cooling tower 4 to the hydrogen gas cooling heat exchanger 5 via the cooling water pipe 4a to exchange heat with the hydrogen gas to cool the hydrogen gas. Further, in the hydrogen gas air supply system 100 of this example, the cooling water W whose temperature has risen due to heat exchange with hydrogen gas in the hydrogen gas cooling heat exchanger 5 is collected in the cooling tower 4 via the cooling water pipe 4b. A reusable configuration is adopted. Instead of the configuration for recovering the cooling water W, after the heat exchange of the cooling water W supplied from the cooling tower 4 to the hydrogen gas cooling heat exchanger 5 with the hydrogen gas is completed (hydrogen gas cooling heat exchanger). It is also possible to adopt a configuration in which the water is drained without being collected (when it is discharged from 5).

The hydrogen gas cooling heat exchanger 5 is a “shell & coil heat exchanger” which is an example of a “heat exchanger”, and as shown in FIG. 3, the first heat exchange unit 41 and the second heat exchange N = 5 "heat exchange units" of the unit 42, the third heat exchange unit 43, the fourth heat exchange unit 44, and the fifth heat exchange unit 45 are housed in the container body 30 and exchange heat with the cooling water W. It is configured to be able to cool hydrogen gas. In this case, the container body 30 corresponds to the “container body”, and as an example, the pipe connection portion 51a (an example of the “fluid introduction portion”) to which the above-mentioned cooling water pipe 4a can be connected and the cooling water pipe 4b are connected. Each heat exchange unit 41 to includes a tubular portion 31 provided with a possible pipe connection portion 51b (an example of a “fluid discharge portion”) and lid portions 32a and 32b that close both ends of the tubular portion 31. It forms a closed space that can accommodate 45.

The first heat exchange unit 41 is an example of the “first heat exchange unit”, and as shown in FIG. 2, the hydrogen gas compressed by the first stage compressor 11 of the multi-stage compressor 1 (second stage compression). The hydrogen gas before the second stage compression by the machine 12) is cooled by heat exchange with the cooling water W. As shown in FIGS. 1 and 2, the first heat exchange unit 41 has one end (hydrogen gas) to the pipe connection portion 61a to which the hydrogen gas pipe 21a connected to the discharge port of the first stage compressor 11 can be connected. The other end (hydrogen gas discharge part) is connected to the pipe connection part 61b to which the hydrogen gas pipe 21b connected to the air supply port of the second stage compressor 12 can be connected. There is.

Further, as shown in FIG. 2, the second heat exchange unit 42 is a hydrogen gas compressed by the second stage compressor 12 of the multi-stage compressor 1 (hydrogen gas before the third stage compression by the third stage compressor 13). ) Is cooled by heat exchange with the cooling water W. As shown in FIGS. 1 and 2, the second heat exchange unit 42 has one end (hydrogen gas) to the pipe connection portion 62a to which the hydrogen gas pipe 22a connected to the discharge port of the second stage compressor 12 can be connected. The other end (hydrogen gas discharge part) is connected to the pipe connection part 62b to which the hydrogen gas pipe 22b connected to the air supply port of the third stage compressor 13 can be connected. There is.

Further, as shown in FIG. 2, the third heat exchange unit 43 is a hydrogen gas compressed by the third stage compressor 13 of the multi-stage compressor 1 (hydrogen gas before the fourth stage compression by the fourth stage compressor 14). ) Is cooled by heat exchange with the cooling water W. As shown in FIGS. 1 and 2, the third heat exchange unit 43 has one end (hydrogen gas) to the pipe connection portion 63a to which the hydrogen gas pipe 23a connected to the discharge port of the third stage compressor 13 can be connected. The other end (hydrogen gas discharge part) is connected to the pipe connection part 63b to which the hydrogen gas pipe 23b connected to the air supply port of the fourth stage compressor 14 can be connected. There is.

Further, as shown in FIG. 2, the fourth heat exchange unit 44 is a hydrogen gas compressed by the fourth stage compressor 14 of the multi-stage compressor 1 (hydrogen gas before the fifth stage compression by the fifth stage compressor 15). ) Is cooled by heat exchange with the cooling water W. As shown in FIGS. 1 and 2, the fourth heat exchange unit 44 has one end (hydrogen gas) to the pipe connection portion 64a to which the hydrogen gas pipe 24a connected to the discharge port of the fourth stage compressor 14 can be connected. The other end (hydrogen gas discharge part) is connected to the pipe connection part 64b to which the hydrogen gas pipe 24b connected to the air supply port of the fifth stage compressor 15 can be connected. There is.

Further, the fifth heat exchange unit 45 is an example of the “N = 5 heat exchange unit”, and as shown in FIG. 2, the hydrogen gas compressed by the fifth stage compressor 15 of the multi-stage compressor 1 ( The hydrogen gas stored in the gas tank 2) is cooled by heat exchange with the cooling water W. As shown in FIGS. 1 and 2, the fifth heat exchange unit 45 has one end (introduction of hydrogen gas) to the pipe connection portion 65a to which the hydrogen gas pipe 25a connected to the discharge port of the fifth stage compressor 15 can be connected. The other end (hydrogen gas discharge part) is connected to the pipe connection part 65b to which the hydrogen gas pipe 25b connected to the gas tank 2 can be connected.

Further, in the heat exchanger 5 for cooling hydrogen gas of this example, each of the above heat exchange units 41 to 45 is spirally wound with a tube body (for example, a round tube) through which hydrogen gas can pass. It is configured with each "heat transfer coil". Further, in the heat exchanger 5 for cooling hydrogen gas in this example, as an example, a plurality of "heat transfer coils" in which two heat exchange units of the first heat exchange unit 41 and the second heat exchange unit 42 are connected in parallel. (An example of the configuration in which "at least one of the heat exchange units" is "two of the first heat exchange unit 41 and the second heat exchange unit 42").

Specifically, as shown in FIG. 3, the first heat exchange unit 41 is in series with the heat transfer coils 71a1 and 71b1 connected in series between the pipe connection portions 61a and 61b attached to the lid portion 32a. The connected heat transfer coils 71a2 and 71b2 are connected in parallel via the branch merging metal fittings 71ta and 71tb. In this case, in the first heat exchange section 41, the hydrogen gas flow path from the branch merging metal fittings 71ta to the branch merging metal fittings 71tb via the heat transfer coils 71a1 and 71b1 and the heat transfer coil 71a2 from the branch merging metal fittings 71ta. , 71b2 is configured so that the hydrogen gas flow path leading to the branching / merging metal fitting 71tb has the same length.

Further, the second heat exchange portion 42 includes heat transfer coils 72a1, 72b1 connected in series between the pipe connection portions 62a and 62b attached to the lid portion 32b, and heat transfer coils 72a2 and 72b2 connected in series. Are connected in parallel via branching and merging metal fittings 72ta and 72tb. In this case, in the second heat exchange section 42, the hydrogen gas flow path from the branch merging metal fitting 72ta to the branch merging metal fitting 72tb via the heat transfer coils 72a1 and 72b1 and the heat transfer coil 72a2 from the branch merging metal fitting 72ta. , 72b2 is configured so that the hydrogen gas flow path leading to the branching / merging metal fitting 72tb has the same length.

Further, in the third heat exchange unit 43, the heat transfer coils 73a and 73b are connected in series between the pipe connection portions 63a and 63b attached to the lid portion 32b, and the fourth heat exchange portion 44 is connected to the lid portion 32b. Heat transfer coils 74a and 74b are connected in series between the attached pipe connection portions 64a and 64b, and the fifth heat exchange portion 45 transfers heat between the pipe connection portions 65a and 65b attached to the lid portion 32a. The thermal coils 75a and 75b are connected in series.

Further, in the heat exchanger 5 for cooling hydrogen gas in this example, the cross-sectional opening area of the pipe body in the heat transfer coils of the heat exchange portions 41 to 45 is the heat transfer portion of the heat exchange portion on the subsequent stage side of the heat exchange portion. It is configured to be equal to or larger than the cross-sectional opening area of the tubular body in the coil.

Specifically, in the first heat exchange section 41 in which the heat transfer coils 71a1, 71b1 and the heat transfer coils 72a2, 72b2 are connected in parallel, the heat transfer coils 71a1, 71b1, 71a2 are tubular bodies having the same cross-sectional opening area. 71b2 is formed. Further, in the second heat exchange section 42 in which the heat transfer coils 72a1, 72b1 and the heat transfer coils 72a2, 72b2 are connected in parallel, the heat transfer coils 72a1, 72b1, 72a2, 72b2 are formed of tubes having the same cross-sectional opening area. Has been done. Further, in the third heat exchange section 43, both heat transfer coils 73a and 73b are formed of tubes having the same cross-sectional opening area, and in the fourth heat exchange section 44, both heat transfer coils 74a are formed of tubes having the same cross-sectional opening area. , 74b are formed, and in the fifth heat exchange portion 45, both heat transfer coils 75a and 75b are formed of tubes having the same cross-sectional opening area.

Further, in the first heat exchange unit 41 (an example of "a heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the first L = 1-stage compression stroke in the multi-stage compression device"), the heat transfer coil 71a1 (or The sum of the cross-sectional opening area of the tube body constituting the heat transfer coil 71b1) and the cross-sectional opening area of the tube body constituting the heat transfer coil 71a2 (or heat transfer coil 71b2) (hereinafter, simply "cross-sectional opening of the tube body"). The area) is the second heat exchange unit 42 (“heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the compression stroke on the side after the L = 1-stage compression stroke in the multi-stage compressor”. (Example) The cross-sectional opening area of the tube that constitutes the heat transfer coil 72a1 (or heat transfer coil 72b1) and the tube that constitutes the heat transfer coil 72a2 (or heat transfer coil 72b2) of the second heat exchange unit 42. It is formed so as to be equal to or larger than the sum of the cross-sectional opening area of the above (hereinafter, also simply referred to as “cross-sectional opening area of the tube”).

Further, in the second heat exchange unit 42 (an example of "a heat exchange unit that heat-exchanges the gas compressed by the second stage compression stroke in the multi-stage compression device with the cooling fluid"), the cross-sectional opening area of the tube body is large. , 3rd heat transfer unit 43 (an example of "heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the compression stroke on the rear side of the L = two-stage compression stroke in the multi-stage compression device") It is formed so as to be equal to or larger than the cross-sectional opening area of the tube body constituting the 73a (or the heat transfer coil 73b) (hereinafter, also simply referred to as “cross-sectional opening area of the tube body”).

Further, in the third heat exchange unit 43 (an example of "a heat exchange unit that heat-exchanges the gas compressed by the third stage compression stroke in the multi-stage compression device with the cooling fluid"), the cross-sectional opening area of the tube body is large. , 4th heat transfer unit 44 (an example of "heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the compression stroke on the rear side of the L = 3-stage compression stroke in the multi-stage compression device") It is formed so as to be equal to or larger than the cross-sectional opening area of the tube body constituting 74a (or the heat transfer coil 74b) (hereinafter, also simply referred to as “cross-sectional opening area of the tube body”).

Further, in the fourth heat exchange unit 44 (an example of "a heat exchange unit that heat-exchanges the gas compressed by the L = 4th stage compression stroke in the multi-stage compression device with the cooling fluid"), the cross-sectional opening area of the tube body is large. , 5th heat transfer unit 45 (an example of "heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the compression stroke on the rear side of the L = 4-stage compression stroke in the multi-stage compression device") It is formed so as to be equal to or larger than the cross-sectional opening area of the tube body constituting the 75a (or heat transfer coil 75b) (hereinafter, also simply referred to as “cross-sectional opening area of the tube body”).

More specifically, in the heat exchanger 5 for cooling hydrogen gas in this example, as an example, "cross-sectional opening area of the tube body of the first heat exchange section 41"> "cross section of the tube body of the second heat exchange section 42". "Opening area"> "Cross-sectional opening area of the tube of the third heat exchange section 43"> "Cross-sectional opening area of the tube of the fourth heat exchange section 44"> "Cross-sectional opening area of the tube of the fifth heat exchange section 45" Each heat exchange unit 41 to 45 is configured so that the relationship with "" is satisfied. As a result, in the heat exchanger 5 for cooling hydrogen gas in this example, the "cross-sectional opening area of the pipe body of the first heat exchange unit 41" is the "fifth heat exchange unit 45 (an example of the" Nth heat exchange unit "). The condition that the cross-sectional opening area of the pipe body is larger than that of the pipe body is satisfied.

Further, in the heat exchanger 5 for cooling hydrogen gas in this example, the thickness of the tube in the heat transfer coil of each heat exchange section 41 to 45 is the heat transfer coil of the heat transfer section on the front stage side of the heat exchange section. It is configured to be thicker than the thickness of the tube.

Specifically, in the hydrogen gas cooling heat exchanger 5 of this example, each "heat transfer coil" of each of the heat exchange units 41 to 45 is formed of the same material. Further, in the first heat exchange section 41 in which the heat transfer coils 71a1, 71b1 and the heat transfer coils 72a2, 72b2 are connected in parallel, the heat transfer coils 71a1, 71b1, 71a2, 71b2 are formed of tubes having the same thickness. There is. Further, in the second heat exchange section 42 in which the heat transfer coils 72a1, 72b1 and the heat transfer coils 72a2, 72b2 are connected in parallel, the heat transfer coils 72a1, 72b1, 72a2, 72b2 are formed of tubes having the same thickness. There is. Further, in the third heat exchange section 43, both heat transfer coils 73a and 73b are formed by tubes having the same thickness, and in the fourth heat exchange section 44, both heat transfer coils 74a and 74b are formed by tubes having the same thickness. In the fifth heat exchange section 45, both heat transfer coils 75a and 75b are formed of tubes having the same thickness.

Further, in the second heat exchange unit 42 (an example of "a heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the K = second stage compression stroke in the multi-stage compression device"), the heat transfer coil 72a1 (or The thickness of the tube body constituting the heat transfer coil 72b1) and the heat transfer coil 72a2 (or the heat transfer coil 72b2) (hereinafter, also simply referred to as "thickness of the tube body") is the first heat exchange portion 41 (or the heat transfer coil 72b2) on the front stage side. Heat transfer coil 71a1 (or heat transfer coil 71b1) or heat transfer coil of "an example of a heat exchange unit that exchanges heat with a cooling fluid for gas compressed by the compression stroke on the side before the K-stage compression stroke"). It is formed so as to be equal to or larger than the thickness of the tube body constituting the 71a2 (or the heat transfer coil 71b2) (hereinafter, also simply referred to as “thickness of the tube body”).

Further, in the third heat exchange unit 43 (an example of "a heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the K = third stage compression stroke in the multi-stage compression device"), the heat transfer coil 73a1 (or The thickness of the tube body constituting the heat transfer coil 73b1) and the heat transfer coil 73a2 (or the heat transfer coil 73b2) (hereinafter, also simply referred to as “the thickness of the tube body”) is the second heat exchange portion 42 (or the heat transfer coil 73b2) on the front stage side. It is formed so as to be thicker than or equal to the thickness of the tube body of "an example of an example of a heat exchange portion for heat exchange between a gas compressed by a compression stroke on the side before the K-stage compression stroke and a cooling fluid").

Further, in the fourth heat exchange unit 44 (an example of "a heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the K = 4th stage compression stroke in the multi-stage compression device"), the heat transfer coil 74a (or The thickness of the tube body constituting the heat transfer coil 74b) (hereinafter, also simply referred to as "thickness of the tube body") is the third heat exchange portion 43 on the front stage side ("compression stroke on the front stage side of the K stage compression stroke". It is formed so as to be thicker than or equal to the thickness of the tube body of "an example of a heat exchange unit") that exchanges heat with a cooling fluid.

Further, in the fifth heat exchange unit 45 (an example of "a heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the K = 5th stage compression stroke in the multi-stage compression device"), the heat transfer coil 75a (or The thickness of the tube body constituting the heat transfer coil 75b) (hereinafter, also simply referred to as "thickness of the tube body") is the fourth heat exchange portion 44 on the front stage side ("compression stroke on the front stage side of the K stage compression stroke". It is formed so as to be thicker than or equal to the thickness of the tube body of "an example of a heat exchange unit") that exchanges heat with a cooling fluid.

More specifically, in the heat exchanger 5 for cooling hydrogen gas in this example, as an example, "thickness of the tube body of the first heat exchange section 41" <"thickness of the tube body of the second heat exchange section 42" = Each so that the relationship of "thickness of the tube of the third heat exchange section 43" <"thickness of the tube of the fourth heat exchange section 44" <"thickness of the tube of the fifth heat exchange section 45" is satisfied. The heat exchange units 41 to 45 are configured. As a result, in the heat exchanger 5 for cooling hydrogen gas in this example, the "thickness of the tube body of the fifth heat exchange section 45 (an example of the" Nth heat exchange section ")" is "the tube of the first heat exchange section 41". The condition that it becomes thicker than "thickness of the body" is satisfied.

In the heat exchanger 5 for cooling hydrogen gas in this example, the heat transfer coils 72a1, 72b1 and the heat transfer coils 72a2, 72b2 of the second heat exchange section 42 are the heat transfer coils 73a, 73b of the third heat exchange section 43. It is formed of the same tube as the tube that constitutes. As a result, the above-mentioned "thickness of the tube body of the second heat exchange section 42" is in a state of having a withstand voltage performance exceeding the withstand voltage performance required for the second heat exchange section 42, but the same tube body is used. As a result, the number of types of pipes required for manufacturing the hydrogen gas cooling heat exchanger 5 is small because the second heat exchange section 42 and the third heat exchange section 43 are formed. The cost has been reduced.

Further, in the hydrogen gas cooling heat exchanger 5 of this example, the heat exchanger 5 is supplied from the cooling tower 4 via the cooling water pipe 4a, is introduced into the container body 30 from the pipe connection portion 51a, and is introduced into the container body 30 from the pipe connection portion 51b to the cooling water pipe 4b. Considering the amount of heat that the cooling water W recovered to the cooling tower 4 via the heat exchange section 41 to 45 rises in temperature due to heat exchange with hydrogen gas, each heat exchange section 41 to 45 in the container body 30 The placement of is optimized.

Specifically, in the heat exchanger 5 for cooling hydrogen gas in this example, as an example, the position near the pipe connection portion 51a in the container body 30 (upper side in FIG. 3: the portion where the temperature of the cooling water W is sufficiently low). The second heat exchange unit 42, the third heat exchange unit 43, and the fourth heat exchange unit 44 are arranged in the container body 30 and at a position closer to the pipe connection portion 51b in the container body (lower side in FIG. 3: Cooling water W). The first heat exchange section 41 and the fifth heat exchange section 45 are arranged at a portion where the temperature is higher than the portion near the pipe connection portion 51a). Therefore, in the hydrogen gas cooling heat exchanger 5 of this example, the above-mentioned pipe connection portions 61a, 61b and the above-mentioned pipe connection portions 65a, 65b are arranged on the lid portion 32a, and the above-mentioned pipe connection portions 62a, 62b, The pipe connection portions 63a and 63b and the pipe connection portions 64a and 64b are arranged on the lid portion 32b.

In this case, in the compression stroke by the first-stage compressor 11 in the multi-stage compressor 1, the compression by the multi-stage compressor 1 is different from each compression stroke on the rear stage side by the second-stage compressor 12 to the fifth-stage compressor 15. A compression process is performed on the low-pressure hydrogen gas that has not been performed. Therefore, in the compression stroke by the first-stage compressor 11, the compression efficiency (rate of increase in pressure) is extremely high, and the hydrogen gas pumped from the first-stage compressor 11 has a very high temperature. Tend. Therefore, the position of the first heat exchange section 41 for cooling the hydrogen gas pumped from the first stage compressor 11 near the pipe connecting portion 51a in the container body 30 (in the flow path of the cooling water W in the container body 30). When arranged at the upstream position), the cooling water W whose temperature has risen to a high temperature due to the cooling of the high-temperature hydrogen gas is allowed to flow in the container body 30 toward the pipe connection portion 51b.

As a result, when the first heat exchange portion 41 is arranged in the container body 30 at a position closer to the pipe connection portion 51a, the position closer to the pipe connection portion 51b (downstream of the flow path of the cooling water W in the container body 30). It may be difficult to adequately cool the hydrogen gas by another heat exchange unit arranged at the side position). However, if the hydrogen gas has a high temperature such as the hydrogen gas introduced into the first heat exchange unit 41, it can be sufficiently cooled even if the temperature of the cooling water W is slightly high. Therefore, the first heat exchange section 41 for cooling the high-temperature hydrogen gas pumped from the first-stage compressor 11 is located closer to the pipe connection section 51b as in the hydrogen gas cooling heat exchanger 5 of this example. It is preferably arranged at (a position on the downstream side of the flow path of the cooling water W in the container body 30).

On the other hand, in the compression stroke by the fifth-stage compressor 15 in the multi-stage compressor 1, the high-pressure hydrogen gas compressed in each compression stroke on the front stage side by the first-stage compressor 11 to the fourth-stage compressor 14 is compressed. .. Therefore, in the compression stroke by the fifth-stage compressor 15 in the multi-stage compressor 1, the compression efficiency is slightly lower than that of each compression stroke on the front stage side, and the hydrogen gas pumped from the fifth-stage compressor 15 is , Tends not to be overly high. Therefore, the fifth heat exchange section 45 for cooling the hydrogen gas pumped from the fifth-stage compressor 15 is located in the container body 30 near the pipe connection portion 51a (in the flow path of the cooling water W in the container body 30). The hydrogen gas can be sufficiently cooled even if the heat is exchanged with the cooling water whose temperature has risen slightly as the hydrogen gas is cooled in the other heat exchange section. Therefore, regarding the fifth heat exchange section 45 that cools the hydrogen gas pumped from the fifth stage compressor 15, another heat exchange section (second heat) like the heat exchanger 5 for cooling the hydrogen gas in this example. The position near the pipe connection portion 51b (in the flow path of the cooling water W in the container body 30) so that the hydrogen gas can be heat-exchanged with the low-temperature cooling water W in the exchange section 42 to the fourth heat exchange section 44). It is preferable to place it in the downstream position).

The amount of temperature increase of the cooling water W accompanying the cooling of the hydrogen gas in the heat exchange units 41 to 45 includes the temperature and flow velocity of the introduced hydrogen gas (hydrogen gas to be treated) and the heat exchange units 41 to 45. It depends on the difference in the diameter (inner diameter and outer diameter) of the "tube". Therefore, the arrangement of the heat exchange portions 41 to 45 (arrangement of the pipe connection portions 61a to 65a, 61b to 65b) is appropriately changed according to the specifications of the multi-stage compressor 1 (compressors 11 to 15). be able to.

Further, in FIG. 3, in order to facilitate understanding of the configuration of the heat exchanger 5 for cooling hydrogen gas, the “heat transfer coils” of the heat exchange units 41 to 45 are shown side by side, but the actual hydrogen is shown. In the gas cooling heat exchanger 5, a part or all of each "heat transfer coil" is composed of "heat transfer coils" having different winding diameters and is arranged concentrically. In such a configuration, the larger the winding diameter, the longer the flow path length of the hydrogen gas, and the smaller the winding diameter, the shorter the flow path length of the hydrogen gas. Therefore, the heat required for the heat exchange units 41 to 45 is required. The arrangement of each "heat transfer coil" is optimized so that the required flow path length is secured according to the exchange capacity.

Next, a method of cooling the hydrogen gas in the compression stroke when the hydrogen gas is stored in the gas tank 2 from the hydrogen gas source X1 in the hydrogen gas air supply system 100 will be described.

When the hydrogen gas supplied from the hydrogen gas source X1 is stored in the gas tank 2, the hydrogen gas is compressed by the multi-stage compression device 1 so that the pressure is suitable for the air supply from the gas tank 2 to the air supply target X2. It is stored in the gas tank 2. At this time, since the hydrogen gas supplied from the hydrogen gas source X1 has a constant pressure, it is difficult to boost the pressure of the hydrogen gas to a sufficient pressure suitable for supply air in one step. Therefore, also in the hydrogen gas supply system 100 of this example, a configuration in which hydrogen gas is compressed in multiple stages (in this example, five stages) by each of the compressors 11 to 15 in the multi-stage compressor 1 is adopted.

Further, in the compression stroke by each compressor 11 to 15, the temperature of hydrogen gas rises due to adiabatic compression. Therefore, the compressor that improves the compression efficiency in the compression stroke on the rear stage side (in this example, the second stage compression stroke to the fifth stage compression stroke) and performs the compression stroke on the rear stage side (compressors 12 to 15 in this example). In order to avoid malfunction and improve the filling efficiency of the gas tank 2, it is necessary to sufficiently cool the hydrogen gas each time each compression stroke is completed. Therefore, also in the hydrogen gas air supply system 100 of this example, the heat exchanger 5 for cooling the hydrogen gas, whose temperature has risen due to adiabatic compression, each time the compression stroke by each of the compressors 11 to 15 in the multi-stage compressor 1 is completed. The configuration to cool by is adopted.

Specifically, when hydrogen gas is compressed by the multi-stage compressor 1 when the hydrogen gas is stored from the hydrogen gas source X1 to the gas tank 2, a water pump (not shown) is operated to operate the water pump from the cooling tower 4 via the cooling water pipe 4a. And supplies the cooling water W. At this time, the supplied cooling water W is introduced into the container body 30 from the pipe connection portion 51a of the container body 30, drained from the pipe connection portion 51b to the cooling water pipe 4b, and collected in the cooling tower 4. That is, in the hydrogen gas air supply system 100, when the water supply of the cooling water W by the water pump is started, the cooling water W is circulated between the cooling tower 4 and the heat exchanger 5 for cooling the hydrogen gas. Since the treatment of cooling (heat dissipation) of the cooling water W in the cooling tower 4 is known, detailed description thereof will be omitted. As a result, as will be described later, cooling water W having a sufficiently low temperature capable of sufficiently cooling the hydrogen gas continues around each of the heat exchange units 41 to 45 (inside the container body 30) in the heat exchanger 5 for cooling the hydrogen gas. It will be in a state of being supplied.

On the other hand, the hydrogen gas supplied from the hydrogen gas source X1 to the first-stage compressor 11 of the multi-stage compressor 1 via the hydrogen gas pipe 20 is compressed in the first-stage compression stroke of the first-stage compressor 11. Air is supplied to the hydrogen gas cooling heat exchanger 5 via the hydrogen gas pipe 21a in a state where the temperature has risen. Further, the hydrogen gas sent through the hydrogen gas pipe 21a is introduced into the first heat exchange unit 41 from the pipe connection portion 61a and cooled by heat exchange with the cooling water W.

Specifically, the hydrogen gas supplied from the first-stage compressor 11 via the hydrogen gas pipe 21a is introduced into the container body 30 from the pipe connection portion 61a and is used for branching and merging via the hydrogen gas pipe. It reaches the metal fitting 71ta and is split into two hands at the branching / merging metal fitting 71ta. Further, the hydrogen gas in one flow is passed through the heat transfer coils 71a1 and 71b1, and the hydrogen gas in the other flow is passed through the heat transfer coils 71a2 and 71b2 and then merges at the branch merging metal fitting 71tb. Then, it reaches the pipe connection portion 61b. At this time, the hydrogen gas passed through the first heat exchange section 41 (each heat transfer coil 71a1, 71b1, 71a2, 71b2, etc.) passes through the container body 30 from the pipe connection portion 51a toward the pipe connection portion 51b. It is cooled by heat exchange with the flowing cooling water W. As a result, the hydrogen gas whose temperature has been sufficiently lowered is sent from the pipe connection portion 61b to the second stage compressor 12 via the hydrogen gas pipe 21b.

Further, the hydrogen gas sent to the second-stage compressor 12 via the hydrogen gas pipe 21b is compressed in the second-stage compression stroke of the second-stage compressor 12, so that the temperature rises in the hydrogen gas pipe. Air is sent to the hydrogen gas cooling heat exchanger 5 via 22a. Further, the hydrogen gas sent through the hydrogen gas pipe 22a is introduced from the pipe connection portion 62a into the second heat exchange portion 42 and cooled again by heat exchange with the cooling water W.

Specifically, the hydrogen gas supplied from the second-stage compressor 12 via the hydrogen gas pipe 22a is introduced into the container body 30 from the pipe connection portion 62a and is used for branching and merging via the hydrogen gas pipe. It reaches the metal fitting 72ta and is split into two hands at the branching / merging metal fitting 72ta. Further, the hydrogen gas in one flow is passed through the heat transfer coils 72a1 and 72b1, and the hydrogen gas in the other flow is passed through the heat transfer coils 72a2 and 72b2 and then merges at the branch merging metal fitting 72tb. Then, it reaches the pipe connection portion 62b. At this time, the hydrogen gas passed through the second heat exchange section 42 (heat transfer coils 72a1, 72b1, 72a2, 72b2, etc.) exchanges heat with the cooling water W flowing in the container body 30. Cooled by. As a result, the hydrogen gas whose temperature has been sufficiently lowered is sent from the pipe connection portion 62b to the third stage compressor 13 via the hydrogen gas pipe 22b.

Further, the hydrogen gas sent to the third-stage compressor 13 via the hydrogen gas pipe 22b is compressed in the third-stage compression stroke of the third-stage compressor 13, so that the temperature rises in the hydrogen gas pipe. Air is sent to the hydrogen gas cooling heat exchanger 5 via 23a. Further, the hydrogen gas sent through the hydrogen gas pipe 23a is introduced into the third heat exchange unit 43 from the pipe connection portion 63a and cooled again by heat exchange with the cooling water W.

Specifically, the hydrogen gas supplied from the third-stage compressor 13 via the hydrogen gas pipe 23a is introduced into the container body 30 from the pipe connection portion 63a, and the hydrogen gas pipe and the heat transfer coil 73a,. After being passed through 73b, it reaches the pipe connection portion 63b. At this time, the hydrogen gas passed through the third heat exchange section 43 (heat transfer coils 73a, 73b, etc.) is cooled by heat exchange with the cooling water W flowing in the container body 30. .. As a result, the hydrogen gas whose temperature has been sufficiently lowered is sent from the pipe connection portion 63b to the fourth stage compressor 14 via the hydrogen gas pipe 23b.

Further, the hydrogen gas sent to the fourth-stage compressor 14 via the hydrogen gas pipe 23b is compressed in the fourth-stage compression stroke of the fourth-stage compressor 14, so that the temperature rises in the hydrogen gas pipe. Air is sent to the hydrogen gas cooling heat exchanger 5 via 24a. Further, the hydrogen gas sent through the hydrogen gas pipe 24a is introduced into the fourth heat exchange unit 44 from the pipe connection portion 64a and cooled again by heat exchange with the cooling water W.

Specifically, the hydrogen gas supplied from the fourth-stage compressor 14 via the hydrogen gas pipe 24a is introduced into the container body 30 from the pipe connection portion 64a, and the hydrogen gas pipe and the heat transfer coil 74a, After being passed through 74b, it reaches the pipe connection portion 64b. At this time, the hydrogen gas passed through the fourth heat exchange section 44 (heat transfer coils 74a, 74b, etc.) is cooled by heat exchange with the cooling water W flowing in the container body 30. .. As a result, the hydrogen gas whose temperature has been sufficiently lowered is sent from the pipe connection portion 64b to the fifth stage compressor 15 via the hydrogen gas pipe 24b.

Further, the hydrogen gas sent to the fifth-stage compressor 15 via the hydrogen gas pipe 24b is compressed in the fifth-stage compression stroke of the fifth-stage compressor 15, so that the temperature rises in the hydrogen gas pipe. Air is sent to the hydrogen gas cooling heat exchanger 5 via 25a. Further, the hydrogen gas sent through the hydrogen gas pipe 25a is introduced into the fifth heat exchange unit 45 from the pipe connection portion 65a and cooled again by heat exchange with the cooling water W.

Specifically, the hydrogen gas supplied from the fifth-stage compressor 15 via the hydrogen gas pipe 25a is introduced into the container body 30 from the pipe connection portion 65a, and the hydrogen gas pipe and the heat transfer coil 75a, After being passed through 75b, it reaches the pipe connection portion 65b. At this time, the hydrogen gas passed through the fifth heat exchange section 45 (heat transfer coils 75a, 75b, etc.) is cooled by heat exchange with the cooling water W flowing in the container body 30. .. As a result, the hydrogen gas whose temperature has been sufficiently lowered is sent from the pipe connection portion 65b to the gas tank 2 via the hydrogen gas pipe 25b and stored in the gas tank 2.

In this case, at the time of multi-stage compression of hydrogen gas by the multi-stage compression device 1, the compression rate of hydrogen gas increases as the compression stroke progresses, and the volume thereof decreases. Therefore, although the configuration is different from that of this example, for example, when the hydrogen gas after compression by the compressors 11 to 15 in the multi-stage compressor 1 is discharged to the pipes having the same cross-sectional opening area, the front stage side. Since the volume of hydrogen gas discharged from the compressor for the compression stroke is larger, the moving speed in the pipe is higher. Further, when the hydrogen gas discharged from the compressor is passed through the pipe having the same cross-sectional opening area, the pressure loss becomes larger as the moving speed is higher.

Therefore, for example, when the cross-sectional opening areas of the pipes of the heat exchange units 41 to 45 in the hydrogen gas cooling heat exchanger 5 are made equal, the pressure loss when passing through the first heat exchange unit 41 is the second heat exchange. The pressure loss when passing through the second heat exchange section 42 becomes larger than the pressure loss when passing through the third heat exchange section 42, and the pressure loss when passing through the third heat exchange section 43 becomes larger than the pressure loss when passing through the third heat exchange section 43. The pressure loss when passing through the fourth heat exchange unit 44 is larger than the pressure loss when passing through the fourth heat exchange unit 44, and the pressure loss when passing through the fourth heat exchange unit 44 is when passing through the fifth heat exchange unit 45. It will be larger than the pressure loss.

Therefore, in the hydrogen gas cooling heat exchanger 5 of this example, in order to reduce the pressure loss generated in the hydrogen gas cooling heat exchanger 5 when cooling the hydrogen gas compressed by the compression stroke on the front stage side, the heat exchanger 5 is used. As described above, the heat exchange portions 41 to 45 are configured so that the cross-sectional opening area of the tubular body becomes larger as the heat exchange portion on the front stage side increases. As a result, the compression efficiency when the hydrogen gas supplied from the hydrogen gas source X1 is stored in the gas tank 2 is sufficiently improved.

Further, in the heat exchanger 5 for cooling hydrogen gas in this example, the heat transfer coils 72a1, 72b1 and the heat transfer coils 72a2, 72b2 of the second heat exchange section 42 are used, and the heat transfer coils 73a, 73b of the third heat exchange section 43 are used. While being formed of the same tubular body as the tubular body constituting the above, the condition of "cross-sectional opening area of the tubular body of the second heat exchange section 42"> "cross-sectional opening area of the tubular body of the third heat exchange section 43" is satisfied. Therefore, the heat transfer coils 72a1, 72b1 and the heat transfer coils 72a2, 72b2 are connected in parallel by the branch merging metal fittings 72ta, 72tb to form the second heat exchange section 42. This is compared with the configuration in which the "heat transfer coil" is formed of a tube having a wider cross-sectional opening area than the tube constituting the heat transfer coils 73a and 73b in order to reduce the pressure loss in the second heat exchange section 42. Therefore, the pressure loss in the second heat exchanger 42 is sufficiently reduced while reducing the number of types of pipes required for manufacturing the hydrogen gas cooling heat exchanger 5.

Further, in the heat exchanger 5 for cooling hydrogen gas in this example, the heat transfer coils 71a1,71b1 and the heat transfer coils 71a2, 71b2 are connected in parallel to the first heat exchange unit 41 by the branch merging metal fittings 71ta, 71tb. It is composed of. In this case, when the first heat exchange section 41 is to be configured without connecting the "heat transfer coils" in parallel, the cross-sectional opening area is sufficiently wide in order to reduce the pressure loss in the first heat exchange section 41. It is necessary to use a tube with a diameter. However, manufacturing a "heat transfer coil" in which a large-diameter tube is spirally wound may increase the manufacturing cost because it is difficult to wind the tube. Therefore, in the heat exchanger 5 for cooling hydrogen gas in this example, as described above, the "heat transfer coil" formed of the small diameter tube is connected in parallel to form the first heat exchange section 41. Its manufacturing cost is sufficiently reduced.

In this case, as described above, in the first heat exchange unit 41 and the second heat exchange unit 42, the amount of hydrogen gas introduced is large and the flow velocity of the hydrogen gas is high, so that a large pressure loss does not occur. , It is necessary to secure a sufficiently wide cross-sectional opening area. However, if a tube having a sufficiently large diameter is used to secure a sufficiently wide cross-sectional opening area, it becomes difficult to manufacture a "heat transfer coil" (bending of the tube). Therefore, in the heat exchanger 5 for cooling the hydrogen gas of this example, as described above, in the first heat exchange section 41 and the second heat exchange section 42 where the amount of hydrogen gas introduced is large and the flow rate of the hydrogen gas is fast, By connecting the heat transfer coils 71a1, 71b1 and the heat transfer coils 71a2, 71b2 in parallel, or by connecting the heat transfer coils 72a1, 72b1 and the heat transfer coils 72a2, 72b2 in parallel, the first heat exchange unit 41 or A configuration is adopted in which the "heat transfer coil" constituting the second heat exchange section 42 is formed of a tubular body having a small diameter. As a result, the heat transfer coils 71a1, 71b1, 71a2, 71b2 constituting the first heat exchange unit 41 and the heat transfer coils 72a1, 72b1, 72a2, 72b2 constituting the second heat exchange unit 42 can be easily manufactured. It is possible.

In addition, when the same "cross-sectional opening area" is secured and the "pressure resistance performance" is matched, it is better than the "heat exchange part" of one flow path (heat transfer coil) composed of a tube having a large inner diameter. The "heat exchange part" of multiple flow paths (heat transfer coils connected in parallel) composed of tubes with a small inner diameter can make the thickness of the tubes that make up the "heat transfer coil" thinner. can. Therefore, in the heat exchanger 5 for cooling hydrogen gas in this example, the heat transfer coils 71a1, 71b1, 71a2, 71b2 constituting the first heat exchange unit 41 and the heat transfer coils 72a1 constituting the second heat exchange unit 42 Since 72b1, 72a2, 72b2 can be formed of a thin tube, each heat transfer coil 71a1, 71b1, 71a2, 71b2, 72a1, 72b1, 72a2, 72b2 can be manufactured more easily. There is.

Furthermore, rather than the "heat exchange section" of one flow path (heat transfer coil) composed of a thick tube, the "heat" of multiple channels (heat transfer coils connected in parallel) composed of a thin tube. The area of the "replacement portion" in contact with the cooling water W in the "heat transfer coil" (total area of the outer surface of the tube) is larger. Therefore, a plurality of "heat transfer units" connected in parallel to the first heat exchange unit 41 and the second heat exchange unit 42 having a high temperature of the introduced hydrogen gas, such as the heat exchanger 5 for cooling the hydrogen gas in this example. By configuring it with a "coil (tube)", it is possible to sufficiently improve the cooling efficiency of hydrogen gas and sufficiently cool it.

Further, in the heat exchanger 5 for cooling hydrogen gas in this example, as described above, "thickness of the tube body of the first heat exchange section 41" <"thickness of the tube body of the second heat exchange section 42" = "first 3 Each heat exchange is satisfied so that the relationship of "thickness of the tube of the heat exchange section 43" <"thickness of the tube of the fourth heat exchange section 44" <"thickness of the tube of the fifth heat exchange section 45" is satisfied. Parts 41 to 45 are configured.

In this case, as described above, the heat exchange section on the front stage side needs to have a larger cross-sectional opening area in order to reduce the pressure loss of the passing hydrogen gas. When all of the "heat coil" is formed of a tube having the same thickness, the outer diameter of the tube of the "heat transfer coil" of the heat exchange portion on the front stage side becomes very large. For this reason, it becomes difficult to manufacture the "heat transfer coil" (winding of the tube) in the heat exchange section on the front stage side, which may increase the manufacturing cost and use a tube that is thicker than necessary. Therefore, the weight of the "heat transfer coil", that is, the total weight of the heat exchanger 5 for cooling the hydrogen gas may be excessively increased, which may make the installation work difficult.

On the other hand, in the heat exchanger 5 for cooling hydrogen gas in this example in which the thickness of the tube body of each heat exchange section is as described above, the "heat transfer coil" of the heat exchange section on the front stage side is easily manufactured. In addition, it is not necessary to have a large pressure resistance due to the low pressure of the hydrogen gas to be processed. The total weight of the heat exchanger 5 is also sufficiently small. This facilitates the installation work of the hydrogen gas cooling heat exchanger 5.

Further, in this example, the hydrogen gas cooling heat exchanger 5 of the "shell & coil type heat exchanger" in which the "heat transfer coils" of the heat exchange units 41 to 45 are housed in the container body 30 and integrated. A configuration is adopted in which heat is exchanged with the cooling water W to cool the hydrogen gas. In this case, when the hydrogen gas is cooled by the "plate heat exchanger" instead of the "shell & coil heat exchanger", the cooling water W enters the cooling water passage groove formed in the cooling water plate. It will be passed. However, when the cooling water W cooled by the cooling tower 4 or the like is used as the "cooling fluid", the cooling water passage groove may be clogged due to the presence of small foreign matter contained in the cooling water W. Therefore, when a "plate heat exchanger" is used, a purification treatment (a treatment for removing foreign matter) of the cooling water W is required, and the operating cost thereof may increase.

On the other hand, in the above-mentioned heat exchanger 5 for cooling hydrogen gas, which is a "shell & coil type heat exchanger", the cooling water W for cooling the hydrogen gas is supplied from each heat exchange unit 41 to the inside of the container body 30. Since it only passes around the 45, even if a small foreign substance is mixed in, the flow path of the cooling water W will not be clogged. Also, when cleaning the flow path of the cooling water W in order to prevent a decrease in heat exchange efficiency due to the adhesion of foreign matter contained in the cooling water W, it adheres as compared with the "plate heat exchanger". Foreign matter can be removed reliably and easily. As a result, it is possible to maintain the heat exchange efficiency between the hydrogen gas and the cooling water W (hydrogen gas cooling efficiency) at a sufficiently high level by performing cleaning as necessary. Therefore, since the purification treatment of the cooling water W to be used is not required, it is possible to avoid an increase in operating cost.

On the other hand, in the state where the hydrogen gas is stored in the gas tank 2 from the hydrogen gas source X1 as described above, the pressure of the hydrogen gas in the gas tank 2 is sufficiently high, so that the pressure in the gas tank 2 is sufficiently high via the dispenser 3. Hydrogen gas can be efficiently supplied to the air supply target X2. Since the supply of hydrogen gas from the gas tank 2 to the air supply target X2 is known, detailed description thereof will be omitted.

As described above, in the hydrogen gas cooling heat exchanger 5, N = 5 heat exchange units 41 to 45 housed in the container body 30 are spirally wound with a tube through which hydrogen gas can pass. Heat exchange units 41 to 44 each include a rotated "heat transfer coil" and exchange heat with the cooling water W for hydrogen gas compressed by the first-stage compression stroke to the fourth-stage compression stroke in the multi-stage compression device 1. The heat exchange sections 42 to 45, in which the cross-sectional opening area of the tube in the "heat transfer coil" exchanges heat with the cooling water W for hydrogen gas compressed by the second-stage compression stroke to the fifth-stage compression stroke on the rear stage side. The cross-sectional opening area of the tube in the "heat transfer coil" is larger than the cross-sectional opening area of the tube, and the cross-sectional opening area of the tube in the "heat transfer coil" of the first heat exchange section 41 is the tube in the "heat transfer coil" of the fifth heat exchange section 45. Each is formed so as to be larger than the cross-sectional opening area of.

Therefore, according to the hydrogen gas cooling heat exchanger 5, N = 5 heat exchange units 41 to 45 for cooling the hydrogen gas in each N = 5 stage compression stroke are housed in the container body 30. For cooling the hydrogen gas, compared to the configuration in which the hydrogen gas is cooled in each N = 5 stage compression stroke by a separate and independent N = 5 heat exchanger (cooler). The space occupied by the required equipment can be made sufficiently small. Further, since the number of the cooling water W pipes can be reduced to a small number, the installation work can be facilitated and the introduction cost can be reduced. Further, by optimizing the cross-sectional opening area of the "heat transfer coil" constituting each of the heat exchange portions 41 to 45, the pressure loss at the time of cooling the hydrogen gas can be sufficiently suppressed.

Further, in the heat exchanger 5 for cooling hydrogen gas, the tube of each "heat transfer coil" in each of the heat exchange units 41 to 45 is formed of the same material, and from the second stage compression stroke in the multi-stage compression device 1. The thickness of the tube in the "heat transfer coil" of the heat exchange units 42 to 45 that exchanges heat with the cooling water W for the hydrogen gas compressed by the 5th stage compression stroke is from the 1st stage compression stroke to the 4th stage on the front stage side. The thickness of the tube in the "heat transfer coil" of the heat exchange units 41 to 44 for heat exchange the hydrogen gas compressed by the compression stroke with the cooling water W, and in the "heat transfer coil" of the fifth heat exchange unit 45. The thickness of the tube is formed so as to be thicker than the thickness of the tube in the "heat transfer coil" of the first heat exchange section 41.

Therefore, according to the hydrogen gas cooling heat exchanger 5, the "heat exchange section" that cools the hydrogen gas after the compression stroke on the rear stage side where the pressure of the hydrogen gas to be processed is high is deformed or damaged. "Heat exchange" that cools the hydrogen gas after the compression stroke on the front stage side where the pressure is not so high while forming the "heat transfer coil" with a "tube" of sufficient thickness that does not cause (leakage of hydrogen gas). As for the "part", by forming the "heat transfer coil" with the thin "tube", the "heat transfer coil" can be easily manufactured and the material cost can be reduced, so that hydrogen gas is used. The manufacturing cost of the cooling heat exchanger 5 can be sufficiently reduced.

Further, according to the hydrogen gas cooling heat exchanger 5, at least one of the heat exchange units 41 to 45 (in this example, two of the first heat exchange unit 41 and the second heat exchange unit 42). Is configured with a plurality of "heat transfer coils" connected in parallel, so that a "heat transfer" formed of a thick "tube" is formed in order to obtain a sufficiently wide cross-sectional opening area that can suppress pressure loss. When a "heat transfer coil" is adopted, it becomes difficult to manufacture the "heat transfer coil" (bending of the "tube", etc.), whereas multiple "heat transfer coils" are connected in parallel to open the required cross section. By obtaining the area, a thin "tube" can be used as the "tube" of each "heat transfer coil", so that the "heat transfer coil" can be easily manufactured, and as a result, for hydrogen gas cooling. The manufacturing cost of the heat exchanger 5 can be sufficiently reduced. Further, even if the same "tube body" is used as the "tube body" constituting the "heat transfer coil" in a plurality of "heat exchange portions", the cross-sectional opening area can be different, so that the same "tube body" can be used. When multiple "heat transfer coils" of "heat exchange parts" are manufactured in "", the material cost, that is, the heat exchanger for cooling hydrogen gas, is reduced by the number of types of "tubes" used. The manufacturing cost of 5 can be further reduced.

Further, according to the hydrogen gas cooling heat exchanger 5, the hydrogen gas as a "gas" can be cooled, so that the hydrogen gas can be supplied to a hydrogen gas fuel cell vehicle or the like like a hydrogen gas station. The hydrogen gas cooling heat exchanger 5 can be installed even in a place where the equipment can be installed in a narrow space, whereby the hydrogen gas compressed by the multi-stage compression device 1 can be suitably cooled.

The configuration of the "heat exchanger" is not limited to the example of the configuration of the hydrogen gas cooling heat exchanger 5 described above. For example, five heat exchange units 41 to 45 that can cool hydrogen gas after five stages of compression strokes from the first stage compression stroke to the fifth stage compression stroke in the multi-stage compression device 1. The explanation was given by taking as an example the heat exchanger 5 for cooling hydrogen gas, which is provided with the "heat exchange section" of (5 steps), but the number of "heat exchange sections" (the number of corresponding compression stroke steps). Can be 2 (2 steps), 3 (3 steps), 4 (4 steps), and 6 or more (6 steps or more) (not shown).

Further, the first heat can cool everything from the hydrogen gas after the first stage compression stroke by the first stage compressor 11 to the hydrogen gas after the fifth stage compression stroke by the fifth stage compressor 15 in the multi-stage compressor 1. The hydrogen gas cooling heat exchanger 5 having N = 5 heat exchange units from the exchange unit 41 to the fifth heat exchange unit 45 has been described as an example, but instead of such a configuration, For a part of each compression stroke by the "multi-stage compressor", it is possible to adopt a configuration in which the compressed hydrogen gas is cooled in another "heat exchanger".

As an example, among the hydrogen gas compressed by the "multi-stage compression device" capable of three-stage multi-stage compression, the hydrogen gas after the first-stage compression stroke and the hydrogen gas after the second-stage compression stroke can be cooled respectively. A "heat exchanger" can be configured with N = 2 "heat exchangers" for each stage (a configuration in which the hydrogen gas after the third stage compression stroke is cooled by another heat exchanger), or the second stage. A "heat exchanger" can be configured with two stages of N = two "heat exchangers" that can cool the hydrogen gas after the compression stroke and the hydrogen gas after the third stage compression stroke, respectively (first). The hydrogen gas after the stage compression stroke can be cooled by another heat exchanger).

As an example of the configuration that "at least one of the heat exchange units is provided with a plurality of heat transfer coils connected in parallel", the heat transfer coils 71a1,71b1 and the heat transfer coils 71a2, 71b2 Heat exchanger 5 for hydrogen gas cooling including a first heat exchange unit 41 in which heat transfer coils 72a1, 72b1 and heat transfer coils 72a2, 72b2 are connected in parallel, and a second heat exchange unit 42 in which heat transfer coils 72a2, 72b2 are connected in parallel. Although the configuration has been described as an example, the number of parallel "heat transfer coils" is not limited to "2" as in the example of the heat exchanger 5 for hydrogen gas cooling, and a plurality of "heat transfer coils" of "3" or more are used. "Heat coils" can be connected in parallel to form one "heat exchange unit".

Further, the third heat exchange unit 43 in which the heat transfer coils 73a and 73b are connected in series, the fourth heat exchange unit 44 in which the heat transfer coils 74a and 74b are connected in series, and the fifth heat in which the heat transfer coils 75a and 75b are connected in series. The configuration of the heat exchanger 5 for cooling hydrogen gas provided with the switching unit 45 and the like has been described as an example, but one "heat transfer coil" may be used to form one "heat transfer unit", or three or more. It is also possible to connect a plurality of "heat transfer coils" in series to form one "heat transfer unit". Furthermore, an example of having a "heat transfer coil" composed of a "round tube" as a "tube" has been described, but the "tube" is not limited to the "round tube", but is also an "elliptical tube" or a "corner". It is also possible to manufacture a "heat transfer coil" by adopting a "tube" as a "tube body".

In addition, the configuration of the hydrogen gas cooling heat exchanger 5 that cools the hydrogen gas by heat exchange between the hydrogen gas which is an example of the "gas to be treated" and the cooling water W which is an example of the "cooling fluid" is configured. As explained by giving an example, a configuration (not shown) in which any fluid (arbitrary liquid and any gas) other than the cooling water W is heat-exchanged with the "gas to be treated" as the "cooling fluid". , It is possible to adopt a configuration (not shown) in which any gas other than hydrogen gas is heat-exchanged with the "cooling fluid" as the "gas to be treated".

100 Hydrogen gas air supply system 1 Multi-stage compressor 2 Gas tank 3 Dispenser 4 Cooling tower 4a, 4b Cooling water piping 5 Heat exchanger for hydrogen gas cooling 11 1st stage compressor 12 2nd stage compressor 13 3rd stage compressor 14th 4-stage compressor 15 5-stage compressor 20, 21a to 25a, 21b to 25b, 26, 27 Hydrogen gas piping 30 Container body 41 1st heat exchange part 42 2nd heat exchange part 43 3rd heat exchange part 44 4th Heat Exchanger 45 Fifth Heat Exchanger 51a, 51b, 61a-65a, 61b-65b Pipe Connection 71a1, 71b1, 71a2, 71b2, 72a1, 72b1, 72a2, 72b2, 73a-75a, 73b-75b Heat Transfer Coil 71ta , 71tb, 72ta, 72tb Branching and merging metal fittings W Cooling water X1 Hydrogen gas source X2 Air supply target

Claims (2)

Heat exchange configured to be connectable to a multi-stage compressor that compresses the gas to be processed in multiple stages, and to cool the gas by heat exchange between the gas compressed by the multi-stage compressor and a cooling fluid. It ’s a vessel,
From the first heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the Ma-stage compression stroke (Ma is a natural number) in the multi-stage compressor, the Mb-stage compression stroke (Mb) in the multi-stage compressor. With N heat exchange units up to the Nth heat exchange unit (N is a natural number of 2 or more and Mb or less) that exchanges heat with the cooling fluid for the gas compressed by (natural number of (Ma + 1) or more). ,
It is provided with a fluid introduction unit into which the cooling fluid can be introduced, a fluid discharge unit capable of discharging the cooling fluid, and a container body in which the N heat exchange units are housed.
Each of the heat exchange units includes a heat transfer coil in which a tube through which the gas can pass is spirally wound , and the tube of each heat transfer coil is formed of the same material . The heat transfer coil of the heat exchange unit that exchanges heat with the cooling fluid for the gas compressed by the L-stage compression stroke (L is each natural number of Ma or more (Mb-1) or less) in the multi-stage compression device. The heat transfer section of the heat exchange unit in which the cross-sectional opening area of the tubular body in the multi-stage compressor exchanges heat with the cooling fluid for the gas compressed by the compression stroke on the later stage side than the L-stage compression stroke in the multi-stage compression device. The cross-sectional opening area of the tube in the coil is equal to or larger than the cross-sectional opening area of the tube, and the cross-sectional opening area of the tube in the heat transfer coil of the first heat exchange section is at least the cross-sectional opening area of the tube in the heat transfer coil of the Nth heat exchange section. The gas, which is formed so as to be larger than the cross-sectional opening area and is compressed by the K-stage compression stroke (K is each natural number of (Ma + 1) or more and Mb or less) in the multi-stage compression device, is heated with the cooling fluid. The heat exchange in which the thickness of the tube in the heat transfer coil of the heat exchange unit to be exchanged heats and exchanges the gas compressed by the compression stroke on the side before the K-stage compression stroke with the cooling fluid. The thickness of the tube in the heat transfer coil of the Nth heat exchange section is at least the thickness of the tube in the heat transfer coil of the first heat exchange section. Each is formed to be thicker than the thickness of
A heat exchanger in which at least one of the heat exchange units is provided with a plurality of heat transfer coils connected in parallel via branching and merging fittings in the container. The heat exchanger according to claim 1 , which is configured to be capable of cooling hydrogen gas as the gas.

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