Hydrogen gas production equipment

Abstract

To provide a hydrogen gas production facility that can effectively use heat generated during operation for anti-freezing purposes as needed.SOLUTION: A hydrogen gas production facility comprises: a heat medium heated by heat generated in a heat generator; and multiple heat exchangers including a first heat exchanger and a second heat exchanger, both for cooling the heat medium heated by the heat. Among the multiple heat exchangers, the first heat exchanger is provided so as to be able to cool the heat medium by exchanging the heat in an accommodation space for accommodating a water electrolysis unit and the second heat exchanger is provided so as to be able to cool the heat medium by exchanging the heat in an outer space or a space different from the first heat exchanger in the accommodation space. A first heat exchange mode for exchanging the heat by the first heat exchanger and a second heat exchange mode for exchanging the heat by the second heat exchanger are switchable.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a hydrogen gas production system including a water electrolysis device in which water is electrolyzed to generate hydrogen gas. In preparation Regarding. [Background technology]

[0002] In recent years, opportunities to utilize hydrogen gas as a clean energy source have been expanding, and a method for obtaining such hydrogen gas is widely known as electrolysis of water. For such hydrogen gas production facilities that utilize the electrolysis of water, measures to prevent freezing of pipes and the like have been studied, as shown in Patent Documents 1 and 2 below.

[0003] In the invention disclosed in Patent Document 1 below, a heating device is used to heat the air inside the housing to prevent freezing. However, the heating device is essentially unnecessary during normal operation and may require a large amount of energy consumption to prevent freezing.

[0004] In the invention disclosed in Patent Document 2 below (see especially paragraph 0032, etc.), the air exhaust pipe is blown with air by an air blower, thereby preventing the air exhaust pipe from freezing. In this invention, the exhaust heat of the air blower is effectively utilized, but it is difficult to effectively utilize the exhaust heat for purposes other than preventing freezing in a specific portion, namely, the air exhaust pipe. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-210529 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-113496 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention provides a hydrogen gas production facility that can effectively utilize heat generated during operation to prevent freezing as needed. Offer The challenge is to [Means for solving the problem]

[0007] above In order to solve the above problems, the present invention provides: A hydrogen gas production facility having a water electrolysis device that electrolyzes water to generate hydrogen gas, and a wall that separates an accommodation space that accommodates the water electrolysis device from an external space, the water electrolysis device unit is provided with at least one heat-generating device that generates heat during operation, a heat medium that is heated by the heat generated by the heat generating device; a plurality of heat exchangers including a first heat exchanger and a second heat exchanger for cooling the heat medium heated by the heat; Among the plurality of heat exchangers, the first heat exchanger is arranged so as to perform heat exchange in the accommodation space to cool the heat medium, and the second heat exchanger is arranged so as to perform heat exchange at a location in the accommodation space different from the first heat exchanger or to perform heat exchange in the external space to cool the heat medium, The present invention provides a hydrogen gas production facility that can be switched between a first heat exchange mode in which heat is exchanged by the first heat exchanger and a second heat exchange mode in which heat is exchanged by the second heat exchanger. [Effects of the Invention]

[0008] In the hydrogen gas production facility of the present invention, the exhaust heat from the heat-generating equipment is effectively utilized to heat the facility, thereby preventing freezing. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic front view showing the appearance of a hydrogen gas production facility according to an embodiment; [Figure 2]1 is a schematic front view showing the arrangement of devices inside a hydrogen gas production facility according to an embodiment. FIG. [Figure 3] FIG. 10 is a schematic front view showing an example of ventilation in the first ventilation mode. [Figure 4] FIG. 10 is a schematic front view showing another example of ventilation in the first ventilation mode. [Figure 5] FIG. 10 is a schematic front view showing an example of ventilation in the second ventilation mode. [Figure 6] FIG. 10 is a schematic front view showing another example of ventilation in the second ventilation mode. [Figure 7] FIG. 10 is a schematic front view showing the arrangement of devices inside a hydrogen gas production facility according to another embodiment. [Figure 8] 1A and 1B are schematic diagrams showing the state of a facility equipped with a heat storage device (state during heat storage (a) and state during utilization of the stored heat (b)). [Figure 9] 1A and 1B are schematic diagrams showing another facility equipped with a heat storage device (a) showing the state during heat storage, and (b) showing the state during utilization of the stored heat). DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, a hydrogen gas production facility and a hydrogen gas production method according to preferred embodiments of the present invention will be described. First, a hydrogen gas production facility according to a first embodiment will be described.

[0011] (First embodiment) The hydrogen gas production facility of this embodiment has a water electrolysis unit in which water is electrolyzed to generate hydrogen gas, and a wall that separates an accommodation space that accommodates the water electrolysis unit from an external space. The hydrogen gas production equipment in this embodiment may be a portable type equipped with casters or the like, or may be a stationary type that cannot be moved in its current state. When the hydrogen gas production equipment is portable, the wall portion may be configured as what is called a "casing" or the like. When the hydrogen gas production facility is a stationary type, the wall portion may be configured as what is called a "casing" or the like, such as a concrete structure that constitutes a room in a building.

[0012] An example of a stationary type installed outdoors will be shown below, and an example of hydrogen gas production equipment will be described with reference to the drawings. The hydrogen gas production facility 100 of this embodiment illustrated in FIGS. 1 and 2 has a horizontally elongated rectangular parallelepiped shape. 1 and 2 (X direction in the drawings) may be referred to as the "left-right direction," "width direction," or "lateral direction" of the hydrogen gas production facility 100. In the following description, the up-down direction (Y direction in the drawing) may be referred to as the "up-down direction," "height direction," or "vertical direction" of the hydrogen gas production facility 100. Furthermore, in the following, the depth direction in FIGS. 1 and 2, which is perpendicular to the X and Y directions in the drawings, may be referred to as the "depth direction" or "front-rear direction" of the hydrogen gas production facility 100.

[0013] The wall portion 10 of the hydrogen gas production equipment 100 of this embodiment extends along the sides of the rectangular parallelepiped shape and comprises a frame 11 that forms the framework of the wall portion 10, and a plurality of wall panels 12 attached to the frame 11. The frame 11 comprises four foundation beams 11a arranged to correspond to the four sides of the rectangle that defines the bottom surface of the rectangular parallelepiped, four pillars 11b rising from the four corners of the bottom surface, and four ceiling beams 11c arranged to correspond to the four sides of the rectangle that defines the top surface of the rectangular parallelepiped and connecting the upper ends of the pillars 11b.

[0014] Auxiliary columns 11d are further provided on the long sides of the rectangle that defines the bottom surface in addition to the two columns 11b arranged at both ends. The auxiliary columns 11d of the frame 11 are arranged to rise from midpoints of the two long sides that face each other in the front-rear direction. The auxiliary columns 11d are arranged in pairs in the front-rear direction and provided on the frame 11 in one or more pairs. The frame 11 is further provided with an auxiliary beam 11e that connects the lower ends of the two auxiliary columns 11d together, and an auxiliary beam (not shown) that connects the upper ends of the auxiliary columns 11d together.

[0015] The wall panel 12 of the wall portion 10 is attached to the outside of the frame 11 so as to be detachable from the frame 11. The wall panel 12 includes a side wall panel 12a that constitutes the side wall of the wall portion 10, a ceiling panel 12b that constitutes the ceiling wall, and a bottom panel 12c that constitutes the bottom wall.

[0016] The hydrogen gas production facility 100 of this embodiment has the storage space, which is a horizontally elongated rectangular parallelepiped shape and is slightly smaller than the wall portion 10, inside the wall portion 10. That is, the storage space in the hydrogen gas production equipment 100 of this embodiment is formed so that the first horizontal direction (X direction in Figures 1 and 2) is the longitudinal direction, and the direction perpendicular to the first horizontal direction (depth direction) is the short side direction.

[0017] The side wall panel 12a includes side panels 12as located at both longitudinal ends of the storage space and constituting the first and second side walls of the wall portion 10 facing each other across the storage space, and further includes a front panel 12af and a back panel 12ab located at both lateral ends of the storage space and constituting the third and fourth side walls facing each other across the storage space. More specifically, the side wall panel 12a includes a first side panel 12as1 that constitutes the first side wall on the left side when viewed from the front in Figures 1 and 2, and a second side panel 12as2 that constitutes the second side wall on the right side when viewed from the front. The side wall panel 12a also includes a front panel 12af attached to the frame 11 from the front side to form the third side wall, and a back panel 12ab attached to the frame 11 from the back side to form the fourth side wall.

[0018] Each of the two side panels 12as, which are located at both longitudinal ends of the storage space and arranged opposite each other in the longitudinal direction, is provided with a ventilation opening that connects the storage space inside the wall portion 10 with the external space outside the wall portion 10, and provides ventilation between the external space and the storage space. That is, the wall portion 10 of this embodiment is provided with a plurality of ventilation openings 13 for ventilating between the external space and the storage space. In this embodiment, the plurality of ventilation openings are provided so that ventilation can be achieved by exhausting air through one ventilation opening and supplying air through another ventilation opening. As will be described later, the water electrolysis unit 20 of this embodiment is provided with heat-generating equipment that generates heat when in operation. In the hydrogen gas production facility 100 of this embodiment, heat generated in the accommodation space by the heat-generating devices is discharged to the external space during the ventilation through the plurality of ventilation openings 13 .

[0019] The hydrogen gas production equipment 100 of this embodiment is equipped with multiple ventilation openings 13, including a first ventilation opening 13a located at the top left side when viewed from the front in Figures 1 and 2, and a second ventilation opening 13b located on the opposite side of the first ventilation opening 13a across the storage space. That is, the first ventilation opening 13a is provided in the first side panel 12as1, and the second ventilation opening 13b is provided in the second side panel 12as2. The first ventilation opening 13a is disposed on the upper side of the first side panel 12as1, whereas the second ventilation opening 13b is disposed on the lower side of the second side panel 12as2. In this embodiment, the wall portion 10 is further provided with a third ventilation opening 13c in addition to the first ventilation opening 13a and the second ventilation opening 13b, and the third ventilation opening 13c is provided in the first side panel 12as1 in which the first ventilation opening 13a is provided.

[0020] The hydrogen gas production equipment 100 of this embodiment is equipped with an air conditioner 30 so that the temperature of the storage space can be raised as needed, and the first side panel 12as1, on which the first ventilation opening 13a and the third ventilation opening 13c are provided, further has an intake port and an exhaust port for the air conditioner 30. That is, the air conditioner 30 of this embodiment is disposed so as to be able to raise the temperature of the storage space at a position opposite the second ventilation opening 13b in the longitudinal direction of the storage space.

[0021] The wall portion 10 of the hydrogen gas production facility 100 of this embodiment is provided with shutters 14 that open and close the first ventilation opening 13a, the second ventilation opening 13b, and the third ventilation opening 13c. Specifically, the hydrogen gas production equipment 100 of this embodiment is equipped with three shutters 14: a first shutter 14a that can switch the first ventilation outlet 13a between an open state and a closed state, a second shutter 14b that can switch the second ventilation outlet 13b between an open state and a closed state, and a third shutter 14c that can switch the third ventilation outlet 13c between an open state and a closed state.

[0022] The hydrogen gas production equipment 100 of this embodiment is equipped with a second blower fan 15b for taking in air from the external space into the equipment through the second ventilation opening 13b, and a third blower fan 15c for taking in air from the external space into the equipment through the third ventilation opening 13c. In this embodiment, the second blower fan 15b is disposed adjacent to the second ventilation opening 13b, and the third blower fan 15c is disposed adjacent to the third ventilation opening 13c. On the other hand, no fans are arranged adjacent to the first ventilation opening 13a.

[0023] The second ventilation opening 13b and the third ventilation opening 13c are connected inside the wall portion 10 to the excess space in the accommodation space other than the space occupied by the devices that make up the water electrolysis device section 20, while the first ventilation opening 13a is connected to a duct DP that extends from the exhaust port of the rectifier 21, as will be described later, and is in communication with the space around the rectifier 21 through the internal space of the rectifier 21.

[0024] The wall portion 10 of the hydrogen gas production facility 100 of this embodiment is provided with a rectifier 21, which is one of the devices constituting the water electrolysis device portion 20 and is also the heat-generating device. The rectifier 21 is provided with a cooling fan 21b, which can be used to exhaust air from the first ventilation opening 13a.

[0025] The water electrolysis device section 20 of the hydrogen gas production equipment 100 of this embodiment is equipped with multiple devices in addition to the rectifier, and most of these devices are housed inside the wall section 10 by being mounted on the upper surface of the bottom panel 12c.

[0026] The water electrolysis unit 20 has an electrolysis device 22 equipped with an electrolysis cell in which electric power is supplied to electrolyze water, generating oxygen gas on the anode side and hydrogen gas on the cathode side. The water electrolysis unit 20 of this embodiment includes the rectifier 21 for supplying DC power to the electrolysis device 22, a pure water production device 23 for producing pure water to be supplied to the electrolysis device 22, and a pure water tank 24 for storing the pure water produced by the pure water production device 23. The pure water production system 23 includes a filter and an ion exchanger for removing impurities contained in water supplied from the outside to the hydrogen gas production facility 100 through the raw water supply line WL.

[0027] The rectifier 21 may be air-cooled or water-cooled. In this embodiment, the rectifier 21 is an air-cooled type, and an example in which a water-cooled type is used will be described later. The rectifier 21 comprises a housing 21a, a semiconductor element (not shown) housed inside the housing 21a, and a cooling fan 21b that generates an upward airflow inside the housing 21a to cool the semiconductor element.

[0028] The housing 21a has a plurality of slits 21x at its bottom end, which serve as intake ports when an upward flow is generated by the cooling fan 21b. The housing 21a has multiple exhaust ports at its upper end, of which a first exhaust port 21y opens toward the first side panel 12as1 and a second exhaust port 21z opens toward the second side panel 12as2. The rectifier 21 is provided with a shutter 21za for switching the second exhaust port 21z between an open state and a closed state.

[0029] The first exhaust port 21y provided in the housing 21a of the rectifier 21 is connected to the first ventilation port 13a by the duct DP. As described above, the first ventilation port 13a located at the end of the duct DP can be freely opened and closed by the first shutter 14a, so the rectifier 21 of this embodiment can be switched between an external exhaust state in which the warm exhaust air, after becoming the upward flow and cooling the semiconductor elements, is exhausted through the duct DP to the outside space from the first ventilation port 13a, and an internal exhaust state in which it is exhausted into the equipment through the second exhaust port 21z.

[0030] When the length of the duct DP increases, the pressure loss increases in the state of exhausting to the outside. Therefore, the rectifier 21 is disposed at a position closer to the first side panel 12as1 than the center of the housing space in the longitudinal direction. That is, the rectifier 21 of this embodiment is disposed so that the distance to the second ventilation opening 13b is greater than the distance to the first ventilation opening 13a. The duct DP has a length of, for example, 2 m or less. The length of the duct DP may be 1 m or less, or 50 cm or less.

[0031] The electrolytic cell, which receives power supply from the rectifier 21 and performs water electrolysis, has a cathode and an anode, and generates hydrogen gas on the cathode side and oxygen gas on the anode side through the electrolysis. It is configured so that pure water is circulated to the anode side, oxygen gas and hydrogen ions are generated through electrolysis, the hydrogen ions are moved from the anode side to the cathode side, and hydrogen gas is generated on the cathode side. Therefore, the electrolytic cell in this embodiment discharges oxygen gas together with a relatively large amount of water from the anode side, and hydrogen gas together with a relatively small amount of water from the cathode side.

[0032] The water electrolysis unit 20 in the hydrogen gas production facility 100 of this embodiment further includes a water circulation pump 25 for circulating the pure water on the anode side, a gas-liquid separator 26 for separating the gas-liquid mixture of oxygen gas and pure water discharged from the anode side of the electrolysis cell, a polisher 27 for removing ions contained in the pure water circulated by the water circulation pump 25, and a water pipe L1 for forming a circulation path for the pure water passing through these components.

[0033] The water electrolysis unit 20 of this embodiment is further provided with devices for removing moisture from the hydrogen gas produced in the electrolysis device 22, and is further provided with a heat exchanger 28 for cooling the hydrogen gas discharged from the cathode side of the electrolysis cell and converting moisture contained in the form of water vapor into condensed water, a gas-liquid separator 29 for removing moisture such as the condensed water from the hydrogen gas after being cooled in the heat exchanger 28, and a dehumidification device DC that performs a dehumidification treatment using an adsorbent to further remove moisture from the hydrogen gas after moisture has been removed in the gas-liquid separator 29.

[0034] The dehumidifier DC has an adsorption column DCa equipped with a moisture adsorbent (not shown) such as zeolite, and a heater (not shown) that heats the moisture adsorbent to a high temperature (e.g., 200°C or higher) to release the adsorbed moisture from the moisture adsorbent and regenerate the moisture adsorbent. In the water electrolysis unit 20 of this embodiment, a hydrogen gas pipe L2 is installed for transporting hydrogen gas from the gas-liquid separator 29 on the cathode side to the outside of the facility through the dehumidification unit DC.

[0035] The water electrolysis unit 20 of this embodiment is further provided with an oxygen gas pipe L3 for transporting the oxygen gas separated in the gas-liquid separator 26 on the anode side to the outside of the facility.

[0036] The hydrogen gas production equipment 100 of this embodiment is installed outdoors, with a hydrogen discharge path HL for transporting the hydrogen gas transported to the wall portion 10 by the hydrogen gas piping L2 to the use point, an oxygen discharge path OL for discharging the oxygen gas transported to the wall portion 10 by the oxygen gas piping L3 to the outside of the system, and a raw water supply path WL for supplying water from the outside for the electrolysis. In the hydrogen gas production facility 100 of this embodiment, the exhaust heat of the rectifier 21 is effectively utilized to prevent water from freezing in winter and the like.

[0037] As described above, the second exhaust port 21z of the rectifier 21 opens toward the second side panel 12as2 having the second ventilation port 13b. In the hydrogen gas production equipment 100 of this embodiment, at least a portion of the piping through which water and gas flow (water piping L1, hydrogen gas piping L2, oxygen gas piping L3) is arranged between the rectifier 21 (second exhaust port 21z) and the second side panel 12as2 (second ventilation port 13b). In this embodiment, the second exhaust port 21z is set at a higher position than the second ventilation port 13b, and at least a part of the piping is located at an intermediate height between the second ventilation port 13b and the second exhaust port 21z.

[0038] The hydrogen gas production facility 100 in this embodiment is provided with water for electrolysis as described above. In the hydrogen gas production facility 100, there is a small amount of water contained in the hydrogen gas and oxygen gas after electrolysis in the form of mist or water vapor. The water contained in the hydrogen gas or oxygen gas is usually discharged to the outside of the system as condensed water or reused as water for electrolysis. Furthermore, in addition to the condensed water described above, water may be discharged to the outside of the system from each of the cathode side and the anode side of the hydrogen gas production facility 100 .

[0039] As described above, in the hydrogen gas production equipment 100, there is water that is electrolyzed and water that is not electrolyzed and is discharged outside the system (outside the equipment). As will be described in detail later, in the hydrogen gas production equipment 100 of this embodiment, these waters become target waters that are subject to anti-freezing (hereinafter also referred to as "waters to be kept warm"), and anti-freezing is performed by the exhaust heat.

[0040] A method for producing hydrogen gas using the hydrogen gas production facility 100 will be described. In the hydrogen gas production equipment 100 of this embodiment, externally supplied electric power is rectified to direct current in the rectifier 21, and the rectified electric power is supplied to the electrolytic cell of the electrolysis device 22. Water is decomposed by electrolysis in the electrolysis cell to produce hydrogen gas, and the water contained in the hydrogen gas is removed by passing through the gas-liquid separator 29 and the dehumidification device DC, and the hydrogen gas with a sufficiently low dew point is supplied to the point of use through the hydrogen discharge path HL.

[0041] In the hydrogen gas production equipment 100 of this embodiment, predetermined ventilation is carried out when hydrogen gas is being generated in the electrolysis device 22, or when the electrolysis device 22 is not in operation but other devices are in operation. In the hydrogen gas production equipment 100 of this embodiment, it is possible to switch between a first ventilation mode in which exhaust is made through the first ventilation outlet 13a and the heat generated in the storage space is discharged using the first ventilation outlet 13a, and a second ventilation mode in which the heat is discharged through the second ventilation outlet.

[0042] In the hydrogen gas production facility 100 of this embodiment, when it is required to effectively utilize the exhaust heat of the rectifier 21 to prevent the water to be kept warm from freezing, ventilation is performed in the second ventilation mode. Therefore, in the hydrogen gas production method of the present embodiment, ventilation in the second ventilation mode is performed in a state where the temperature of the external space is lower than in the first ventilation mode. In other words, in this embodiment, the average outdoor temperature during the period in a day when ventilation is performed in the second ventilation mode is lower than the average outdoor temperature during the period in a day when ventilation is performed in the first ventilation mode. In ventilation in this second ventilation mode, the warm air inside the rectifier 21 is released into the equipment through the second exhaust port 21z of the rectifier 21, and the heat contained in the warm air is used to heat the piping before the warm air is discharged into the outside space through the second ventilation port, thereby preventing the water to be kept warm from freezing.

[0043] In the hydrogen gas production equipment 100 of this embodiment, one or more of the electrolysis device 22, the water circulation pump 25, the anode-side gas-liquid separator 26, the cathode-side gas-liquid separator 29, etc. may be arranged between the second exhaust port 21z of the rectifier 21 and the second ventilation port 13b, and the warm air may be used to prevent these from freezing.

[0044] As described above, the hydrogen gas production equipment 100 of this embodiment has the air conditioner 30, so even if the risk of freezing is not sufficiently eliminated by simply changing the exhaust from the rectifier 21 to an internal exhaust state, the air conditioner 30 can be used to raise the temperature of the storage space. In this embodiment, the air conditioner 30 is located on the opposite side of the second ventilation opening 13b, so when the air conditioner 30 is operated in the second ventilation mode, the warm air generated by the air conditioner 30 can be used extremely effectively to prevent the water to be kept warm from freezing. The hydrogen gas production facility 100 of this embodiment may further include an antifreeze heater for directly heating at least a portion of the piping to prevent the water in the piping from freezing.

[0045] Each ventilation mode is described in detail below. Ventilation in the first ventilation mode can be performed using one or both of the cooling fan 21b of the rectifier 21 and the second blower fan 15b. Figure 3 shows a simulated airflow movement in the first ventilation mode using arrows. Ventilation in the first ventilation mode can be performed, for example, by opening the first shutter 14a and the second shutter 14b, closing the third shutter 14c and the shutter 21za of the rectifier 21, and exhausting the air inside the housing of the rectifier 21 to the outside space through the duct DP using the cooling fan 21b. At this time, negative pressure is applied upstream of the cooling fan 21b (below in the figure) due to exhaust air being discharged downstream (above in the figure), and surrounding air is drawn into the housing through the slit 21x provided at the lower end of the housing a of the rectifier 21. Then, new air that replaces the air drawn into the housing is introduced into the accommodation space through the second ventilation opening 13b, thereby forming an air flow as shown in FIG. 3 within the equipment.

[0046] The air flow shown in Figure 3 can also be formed by stopping the cooling fan 21b and operating only the second blower fan 15b to send air in using the second blower fan 15b to create positive pressure inside the equipment. When the cooling fan 21b is not used, the shutter 21za of the rectifier 21 may be opened as shown in FIG. 4 to draw air into the rectifier through the second exhaust port 21z. Furthermore, in such a case, the third blower fan 15c may be used in combination with the second blower fan 15b to create a positive pressure inside the facility.

[0047] In this first ventilation mode, the rectifier 21, which is a heat-generating device that generates a large amount of heat, is located downstream in the direction in which the airflow is formed, and since it is located near the first ventilation opening 13a, much of the heat generated within the equipment can be quickly discharged.

[0048] The electrolysis device 22 generates heat due to Joule heat when producing hydrogen gas. Furthermore, even when hydrogen gas is not being produced, when the hydrogen gas production facility 100 is in an operating state in which the adsorbent is regenerated in the adsorption column DCa, heat is also generated in the dehumidification device DC. In this embodiment, in addition to the rectifier 21, the hydrogen gas production equipment 100 is equipped with heat-generating equipment such as the electrolysis device 22 and the dehumidification device DC. However, by forming air flows as shown in Figures 3 and 4 within the equipment, these devices are prevented from excessively increasing in temperature. In this embodiment, it is not necessary for all heat-generating devices to be located near the first ventilation opening 13a, but it is preferable that the rectifier 21, which generates a large amount of heat, be located near the first ventilation opening 13a.

[0049] In the hydrogen gas production facility 100, hydrogen gas may leak due to unexpected reasons. In order to prevent hydrogen gas from accumulating in the equipment in the event that hydrogen gas leaks from the electrolysis device 22, the hydrogen gas pipe L2, or the like, it is preferable to ensure a certain level of ventilation volume in the first ventilation mode.

[0050] In the first ventilation mode, it is preferable to ensure a ventilation rate of 2 times / h or more, and it is more preferable to ensure a ventilation rate of 3 times / h or more. The ventilation rate is more preferably 4 times / h or more, and particularly preferably 5 times / h or more. The ventilation rate can usually be set to 15 times / h or less.

[0051] The ventilation rate can be determined by measuring how many times the amount of air (V1) newly introduced into the storage space from the outside space per hour is multiplied by the volume (V0) of the storage space. Ventilation rate (times / h) = V1 (m 3 / h) / V0(m 3 )

[0052] The volume (V0) of the storage space can be found by calculating the volume of the space inside the inner wall surface of the wall portion 10. In this embodiment, the distance from the first side panel 12as1 to the second side panel 12as2 is the length (L) of the storage space, the distance from the front panel 12af to the back panel 12ab is the depth (D) of the storage space, and the distance from the bottom panel 12c to the ceiling panel 12b is the height (H) of the storage space, and the volume of the storage space can be calculated as follows. Volume of storage space (V0) = Length (L) x Depth (D) x Height (H) of storage space

[0053] The amount of air (V1) newly introduced into the storage space can be calculated by measuring the average surface wind speed at each ventilation opening using an anemometer or the like, and multiplying this average surface wind speed by the opening area of ​​the ventilation opening.

[0054] From the viewpoint of both disposing of exhaust heat and preventing accumulation of hydrogen gas, in the first ventilation mode, it is preferable that the air supply point and the air exhaust point are provided at positions facing each other across the accommodation space. That is, in the hydrogen gas production equipment 100 of this embodiment, the wall portion 10 has a first side wall and a second side wall that face each other across the storage space, and the first ventilation opening 13a is provided in the first side wall and the second ventilation opening 13b is provided in the second side wall, so that it is easier for the air newly introduced into the equipment during ventilation in the first ventilation mode to spread throughout the entire equipment, and it is less likely that areas will be formed within the equipment where warm air or hydrogen gas will stagnate. This also applies to ventilation in the second ventilation mode.

[0055] In the first ventilation mode, the second blower fan 15b and the third blower fan 15c blow air from the external space into the equipment, which introduces the exhaust heat of these fans into the accommodation space, is advantageous for dissipating heat from the viewpoint of increasing the number of ventilation cycles, and a large benefit can be obtained by increasing the number of ventilation cycles. Therefore, in ventilation in the first ventilation mode, if the purpose of ventilation is to exhaust heat and prevent accumulation of hydrogen gas, it may be advantageous to use the second blower fan 15b and the third blower fan 15c.

[0056] Ventilation in the second ventilation mode can be performed, for example, by opening the second shutter 14b and the third shutter 14c as shown in FIG. 5 and using a third blower fan 15c to introduce air into the equipment through the third ventilation opening 13c. In the second ventilation mode, the air near the rectifier 21 that has been heated by the rectifier 21 passes by the pipes (water pipe L1, hydrogen gas pipe L2, oxygen gas pipe L3) and is discharged from the second ventilation port 13b. Therefore, ventilation in the second ventilation mode can be said to be an effective ventilation method in situations where there is a risk of water freezing in pipes or the like. Instead of sending air into the equipment using the third blower fan 15c through the third ventilation opening 13c, it is also possible to perform ventilation in the second ventilation mode by sucking air out of the equipment through the second ventilation opening 13b, but in that case, the exhaust heat from the blower fan will not be introduced into the equipment. In other words, in the first ventilation mode, when it is required to quickly exhaust heat from within the equipment to the outside space, it is advantageous to use a blower to exhaust air to the outside space as described above, but in the second ventilation mode, when preventing freezing, it is advantageous to use a blower to supply air to the storage space.

[0057] In order to be able to both exhaust air to the external space and supply air from the external space, the second blower fan 15b and the third blower fan 15c may be propeller fans and may also be reversible flow fans (bidirectional fans) that can blow air in both forward and reverse directions by rotating the propeller forward and backward.

[0058] In ventilation in the second ventilation mode, the shutter 21za of the rectifier 21 may be opened as shown in FIG. 6, and the cooling fan 21b may be operated to exhaust warm air from inside the housing 21a through the second exhaust port 21z. At this time, the air volume of the cooling fan 21b may be the same as or different from that in the first ventilation mode.

[0059] When hydrogen gas is being produced, the water circulating on the anode side, the oxygen gas generated at the anode, and the hydrogen gas generated at the cathode side are all heated by the heat generated in the electrolytic cell, so there is little risk of freezing, and it is more important to address the risk of leaked hydrogen gas accumulating within the equipment. On the other hand, when hydrogen gas is not being produced, the risk of hydrogen gas accumulating in the equipment decreases, but the risk of the water to be kept warm freezing increases. Therefore, it is preferable that ventilation in the first ventilation mode is performed during a period when hydrogen gas is being generated in the electrolysis device 22, and it is preferable that ventilation in the second ventilation mode is performed during a period when hydrogen gas is not being generated in the electrolysis device 22. When hydrogen gas is not being produced by the electrolysis device 22, the internal heat generation of the rectifier 21 is usually small. Therefore, it is preferable to change the air volume of the cooling fan 21b between the first ventilation mode and the second ventilation mode. In the first ventilation mode, no special control is performed and the airflow rate of the cooling fan 21b is kept constant, but in the second ventilation mode, it is preferable to control the airflow rate based on information such as the temperature inside the equipment and the outside temperature.

[0060] The ventilation volume (ventilation rate) in the second ventilation mode may be the same as or different from that in the first ventilation mode. In order to prevent the accumulation of hydrogen gas within the facility, it is preferable that ventilation in the second ventilation mode be carried out at the same air volume (ventilation rate) as in the first ventilation mode.

[0061] The second ventilation mode is preferably implemented in a plurality of sub-modes, and the plurality of sub-modes preferably includes at least one high ventilation sub-mode having a higher ventilation volume per unit time than the other sub-modes, and a low ventilation sub-mode having a lower ventilation volume per unit time than the other sub-modes.

[0062] If ventilation in multiple submodes as described above is possible, for example, at the end of a day's operation, power supply to the electrolytic cell is stopped and ventilation is carried out in the high ventilation submode, which has a ventilation rate similar to that of the first ventilation mode, for a while, and then the mode is switched to the low ventilation submode, thereby preventing the temperature inside the equipment from dropping due to the introduction of air from the outside space.

[0063] Here, we will explain in more detail the desirable ventilation method using a hydrogen gas production cycle model in which hydrogen gas production equipment 100, which has been shut down overnight, is started up in the morning, produces hydrogen gas during the day, and then shuts down again overnight.

[0064] When hydrogen gas production begins in the morning, first, the water circulation pump 25 of the hydrogen gas production equipment 100 is driven to circulate pure water on the anode side, and then the rectifier 21 supplies power to the electrolysis device 22 to begin electrolysis of water. At the same time, the cooling fan 21b of the rectifier 21 is operated to perform ventilation in the first ventilation mode. At this point, the temperature inside the rectifier 21 is not so high, and the temperature of the exhaust air discharged from the first ventilation opening 13a is only slightly higher than the air temperature inside the equipment. Thereafter, the temperature inside the housing of the rectifier 21 rises over time, and reaches a peak during the day. Then, as the outside air temperature drops in the evening, the temperature of the air drawn in through second ventilation opening 13b drops, and the temperature inside the housing of rectifier 21 also starts to drop. The first ventilation mode may be switched to the second ventilation mode at this point, or at the point when the temperature inside the housing of rectifier 21 drops below a certain level (hereinafter also referred to as "point A"). Thereafter, when power supply to the electrolysis device 22 is stopped to prevent new generation of hydrogen gas, the rectifier 21 generates almost no waste heat, and the temperature inside the housing decreases at a rapid rate. The first ventilation mode may be switched to the second ventilation mode at this point, or at the point when power supply from the rectifier 21 is stopped (hereinafter also referred to as "point B"). If the dehumidifier DC and other devices are operating even after the power supply to the electrolysis device 22 is stopped, part of the heat generated by the thermal regeneration of the adsorption columns will prevent the temperature inside the facility from dropping. However, at the point in time when the operation of the dehumidifier DC is also stopped (hereinafter also referred to as "point C"), the temperature drop inside the equipment will accelerate in conjunction with the drop in the outside air temperature. The switch from the first ventilation mode to the second ventilation mode may occur at this "point C." Furthermore, as the outside temperature drops significantly from midnight to dawn, the temperature inside the equipment drops sharply due to ventilation, and in winter there is a risk of freezing. If the equipment is installed in a cold region, there is a risk of freezing not only in winter. Therefore, it is preferable that the ventilation is ultimately performed in a second ventilation mode, and that this second ventilation mode is performed in a low ventilation sub-mode.

[0065] When switching to the second ventilation mode at the "time point A," it is desirable to perform ventilation in the manner shown in FIG. 6, and it is desirable to perform ventilation while performing air cooling with the cooling fan 21b. When switching to the second ventilation mode at "time point B," ventilation does not need to be performed in the manner shown in FIG. 6, and ventilation may be performed in the manner shown in FIG. When the ventilation mode is switched from the first ventilation mode to the second ventilation mode at "time point B," if ventilation is performed in the manner shown in Figure 5, the rectifier 21 will be in a state of storing heat for a while. Therefore, if the second ventilation mode is started in the manner shown in Figure 5 and then switched to the manner shown in Figure 6 when the temperature inside the equipment drops below the specified value, it will be more effective in preventing freezing. When switching to the airflow shown in FIG. 6, the high ventilation sub-mode may be switched to the low ventilation sub-mode.

[0066] The timing of switching from the first ventilation mode to the second ventilation mode and from the high ventilation submode to the low ventilation submode can be set based on one or more of the following information: time of day, outside air temperature, air temperature and water temperature inside the equipment, and internal temperature of the rectifier 21.

[0067] As described above, in this embodiment, hydrogen gas can be produced while avoiding a situation in which the operation of the equipment must be stopped unintentionally due to problems such as freezing. The hydrogen gas production method of this embodiment is not limited to the above-mentioned example, and can be implemented in various forms.

[0068] (Second embodiment) A second embodiment of the present invention will now be described. The invention according to the second embodiment is similar to the first embodiment in that freezing prevention is performed by effectively utilizing exhaust heat. In the first embodiment, the rectifier is an air-cooled type, but in the invention according to the second embodiment, the rectifier may be a water-cooled type as shown in FIG. The hydrogen gas production facility 100 shown in FIG. 7 is provided with a water-cooled rectifier 21', and is therefore not provided with a cooling fan 21b as in the air-cooled rectifier 21 exemplified above. Therefore, in the hydrogen gas production facility 100 shown in FIG. 7, a first blower fan 15a' is provided at the first ventilation opening 13a in place of the cooling fan 21b. The water-cooled rectifier 21' has a cooling mechanism 21e' that cools the semiconductor elements using cooling pipes 21p' through which a cooling liquid is circulated. Therefore, although the temperature around the rectifier 21' rises during operation, it does not become as high as in the case of the air-cooled rectifier 21. However, in the hydrogen gas production equipment 100 shown in Figure 7, the first blower fan 15a' exhausts the warm air around the rectifier 21' to the outside space, allowing ventilation in the first ventilation mode.

[0069] As described above, the hydrogen gas production facility 100 of this embodiment uses the coolant as a heat medium that is heated by the heat generated in the rectifier 21', which is a heat generating device. The hydrogen gas production equipment 100 shown in Figure 7 has multiple heat exchangers, including a first heat exchanger and a second heat exchanger, for cooling the heat medium (coolant) heated by the heat generated in the rectifier 21', as described below.

[0070] In the hydrogen gas production equipment 100 shown in Figure 7, the temperature inside the rectifier 21' does not become as high as in the case of an air-cooled rectifier 21, so the rectifier 21' does not have a first exhaust port 21y or a second exhaust port 21z for discharging warm air from inside the housing. On the other hand, in a hydrogen gas production facility equipped with a water-cooled rectifier 21', the coolant heated by the semiconductor element can be effectively used as a heat source to prevent the water to be kept warm from freezing. For example, the pipes (water pipe L1, hydrogen gas pipe L2, oxygen gas pipe L3) may be heated by the coolant heated by heat exchange with the rectifier 21'.

[0071] Of the water to be kept warm, the water flowing through the circulation path on the anode side is in an environment where it is difficult to freeze because it is actively flowing. Furthermore, even if the water is not actively flowing, a relatively large amount of water such as the water stored in the pure water tank 24 is in an environment where it is difficult to freeze due to its large overall heat capacity. On the other hand, for condensed water (dew condensation water) generated in the gas lines on the cathode and anode sides, the amount is relatively small and the flow is not very active, so it is preferable to prioritize heating using exhaust heat. That is, the hydrogen gas pipe L2 and the oxygen gas pipe L3 can be suitable targets for heating.

[0072] To explain the hydrogen gas production equipment 100 equipped with a water-cooled rectifier 21' in more detail, the hydrogen gas production equipment 100 shown in Figure 7 is configured so that heat generated inside the water-cooled rectifier 21' (semiconductor element) can be transferred to the outside of the rectifier 21' using a cooling liquid as a medium. The hydrogen gas production equipment 100 has a plurality of heat exchangers, including a first heat exchanger and a second heat exchanger, for exchanging heat outside the rectifier to cool the coolant heated by the heat generated in the rectifier 21'. The first heat exchanger in this embodiment is a heating coil 21f' for heating the water to be kept warm. That is, in this embodiment, the cooling pipe 21p' is extended to the outside of the housing 21a' and wrapped around the water piping L1 to form a heating coil 21f' for heating the water piping L1, and the cooling liquid is circulated between the heating coil 21f' and the cooling mechanism 21e' by a pump P' to prevent the water piping L1 and the like from freezing.

[0073] The hydrogen gas production equipment 100 of this embodiment is equipped with an air cooler 21G' that cools the cooling liquid with air in the storage space during periods when the cooling liquid is not used to heat the water to be kept warm (for example, periods when ventilation is performed in the first ventilation mode), and the second heat exchanger constitutes a heat dissipation coil 21g' in the air cooler 21G'. In the hydrogen gas production equipment 100 of this embodiment, the supply destination of the cooling liquid heated in the rectifier 21' can be switched between the first heat exchanger (heating coil 21f') and the second heat exchanger (heat dissipation coil 21g'). In other words, the hydrogen gas production equipment 100 of this embodiment has at least one of the water used for electrolysis and the water discharged outside the system without being electrolyzed as target water to be prevented from freezing, and has a first heat exchanger for transferring heat from the rectifier to heat the target water, and a second heat exchanger for heating the air in the storage space with the heat from the rectifier. As a result, the hydrogen gas production equipment 100 in this embodiment can be switched between a state in which the entire equipment is heated by the second heat exchanger and a state in which a specific part of the equipment is heated by the first heat exchanger.

[0074] The air cooler 21G' may be arranged to directly release the air whose temperature has been increased by cooling the cooling liquid into the external space. Moreover, the air cooler 21G′ may be arranged in the external space outside the wall portion 10, rather than in the storage space inside the wall portion 10.

[0075] The hydrogen gas production equipment 100 according to the second embodiment is a hydrogen gas production equipment 100 having a water electrolysis device section 20 that electrolyzes water to generate hydrogen gas as described above, and a wall section 10 that separates the storage space that houses the water electrolysis device section 20 from the external space, and is common to the hydrogen gas production equipment 100 according to the first embodiment in that the water electrolysis device section 20 is equipped with at least one heat-generating device that generates heat during operation.

[0076] The hydrogen gas production equipment 100 according to the second embodiment has a heat medium that is heated by heat generated by a heat generating device, and has a plurality of heat exchangers, including a first heat exchanger and a second heat exchanger, for cooling the heat medium that has been heated by the heat. Of the plurality of heat exchangers, the first heat exchanger is arranged so that it can exchange heat in the storage space to cool the heat medium, and the second heat exchanger is arranged so that it can exchange heat at a location in the storage space different from the first heat exchanger, or so that it can exchange heat in the external space to cool the heat medium. The hydrogen gas production equipment 100 according to the second embodiment can be switched between a first heat exchange mode in which heat is exchanged using the first heat exchanger and a second heat exchange mode in which heat is exchanged using the second heat exchanger.

[0077] As described above, the hydrogen gas production equipment 100 of the second embodiment has the second heat exchanger positioned in a location that is advantageous for exhausting heat to the outside space, so that, like the hydrogen gas production equipment 100 of the first embodiment, heat generated during operation can be quickly exhausted as needed and the first heat exchanger can be used effectively to prevent freezing. That is, the first heat exchange mode is preferably carried out for the purpose of directly or indirectly heating the water to be kept warm. The second heat exchange mode is preferably performed to release heat generated within the equipment to the outside. In order to achieve the above-mentioned effects more remarkably, it is preferable that the second heat exchanger is disposed so as to be able to cool the heat medium by exchanging heat in the external space.

[0078] In this embodiment, for example, in the first ventilation mode, the cooling liquid is cooled by heat exchange in the air cooler 21G', and in the second ventilation mode, the cooling liquid directly or indirectly exchanges heat with the water to be kept warm to heat (prevent freezing) the water to be kept warm. In this embodiment, the first heat exchange mode and the second ventilation mode can be performed in parallel. In this embodiment, the second heat exchange mode and the first ventilation mode can be performed in parallel.

[0079] In this embodiment, a chiller for producing chilled water may be installed in place of the air cooler 21G', and chilled water may be circulated between the rectifier 21' and the chiller. In this case, the exhaust heat discharged from the chiller may be used to heat the accommodation space or may be released to the outside space.

[0080] When heating the pipes with a coolant, unlike when heating with air, it is easy to concentrate heat at specific locations, so it is possible to heat pinpoint areas that are likely to freeze. In addition, the cooling pipe 21p' may be branched to form heating coils 21f' at multiple locations, in which case a switching mechanism may be provided to switch which of the multiple heating coils 21f' the heated cooling liquid is circulated through. That is, in this embodiment, a third heat exchanger may be further provided so that the water to be kept warm can be heated at a plurality of locations simultaneously. Even in such a case, the warm air around the rectifier 21' can be utilized to prevent freezing by exhausting air from the second ventilation opening 13b provided at a position far from the rectifier.

[0081] The hydrogen gas production equipment 100 of this embodiment has a heat exchanger that heats the water to be kept warm with a cooling liquid heated by the heat generated in the rectifier 21', as well as a sub-heater 21h' as ​​a heating device for heating the water to be kept warm. The sub-heater 21h' may be configured to heat the water to be kept warm using energy supplied to the hydrogen gas production facility 100 from the outside, such as heated steam or grid power. That is, the hydrogen gas production equipment 100 of this embodiment is equipped with a plurality of heating devices including a first heating device (heating coil 21f') and a second heating device (sub-heater 21h') as heating devices for heating the water to be kept warm. The sub-heater 21h' may be provided adjacent to the heating coil 21f', or may be provided at a position separated from the heating coil 21f'.

[0082] In the hydrogen gas production equipment 100 of this embodiment, in order to save energy consumption, it is preferable that the water to be kept warm is heated in the heating coil 21f' (second heat exchanger) prior to heating in the sub-heater 21h', and that heating in the sub-heater 21h' is performed when it is determined that the amount of heat provided by the heating coil 21f' alone is insufficient to prevent freezing.

[0083] The necessity of heating by the sub-heater 21h' is preferably determined based on the temperature of the storage space, the temperature of the external space, or the temperature of the water used for electrolysis, and it is preferable that heating be performed when any of these reference temperatures falls below a reference value. That is, the hydrogen gas production equipment 100 of this embodiment treats at least one of the water used for electrolysis and the water not used for electrolysis but discharged outside the system as target water to be prevented from freezing, and is capable of performing a first heating step in which the target water is heated by the heating coil 21f' using heat from the rectifier 21', and a second heating step in which the target water is heated by a heating method (sub-heater 21h') different from the first heating step, and it is preferable that at least the second heating step is performed based on at least one of the air temperature of the storage space, the air temperature of the external space, and the water temperature of the water used for electrolysis.

[0084] As described above, the water-cooled rectifier 21' is more likely to concentrate heat in a specific location than the air-cooled rectifier 21. Therefore, for example, as shown in FIG. 8, a heat storage device HT may be arranged in the accommodation space so that the exhaust heat generated under circumstances where there is little need for anti-freezing measures can be stored in the heat storage device HT. More specifically, a circulation path for circulating the coolant between the rectifier 21' and a cooling device for cooling the heated coolant discharged from the rectifier 21', such as the air cooler 21G' or the chiller, may be provided, and the heat storage device HT may be arranged upstream of the cooling device. In such an embodiment, a heat transfer medium TL is circulated between the object to be heated Z to be heated and the heat storage device HT to prevent the water to be kept warm from freezing. When there is little need to heat the object to be heated Z, heat is stored solely in the heat storage device HT as shown in Figure 8(a). When there is a need to heat the object to be heated Z, the heat transfer medium TL is supplied from the heat storage device HT to the object to be heated Z as shown in Figure 8(b), thereby preventing freezing.

[0085] The heat storage device HT may be a water tank that simply stores the cooling liquid heated by the rectifier 21', or may be equipped with a sensible heat storage material or a latent heat storage material that stores the heat generated by the rectifier 21'. The heat storage device HT preferably includes a latent heat storage material, which makes it easier to ensure a large amount of heat storage. Examples of the latent heat storage material include paraffin-based heat storage materials having a phase transition temperature in the range of 5°C to 50°C, and hydrate-based heat storage materials. In order to reduce the amount of combustible materials in the storage space, the latent heat storage material is preferably a hydrate-based heat storage material.

[0086] Examples of the hydrate-based heat storage material include sodium sulfate decahydrate-based heat storage material (phase transition temperature: 10°C to 32°C), trimethanolethane trihydrate-based heat storage material (phase transition temperature: 13°C to 30°C), calcium chloride hexahydrate-based heat storage material (phase transition temperature: 27°C), sodium acetate trihydrate-based heat storage material (phase transition temperature: 40°C to 57°C), and sodium thiosulfate pentahydrate-based heat storage material (phase transition temperature: 48°C).

[0087] The coolant used to cool the semiconductor elements in the water-cooled rectifier 21' may be introduced from outside the system. For example, as shown in FIG. 9, a water supply path may be provided to supply a refrigerant CL such as industrial water from outside the system to the rectifier 21′, and a drainage path may be provided to discharge the refrigerant CL to the outside of the system after cooling the rectifier 21′, thereby cooling the semiconductor elements. In this case, as in the example shown in Figure 8, when there is little need to heat the object to be heated Z, heat is stored solely in the heat storage device HT as shown in Figure 9(a), and when there is a need to heat the object to be heated Z, a heat transfer medium TL is supplied from the heat storage device HT to the object to be heated Z as shown in Figure 9(b), thereby preventing freezing.

[0088] In the embodiments shown in FIGS. 8 and 9, a sub-heater 21h' as ​​shown in FIG. 7 may be provided in addition to the heating device using the heat storage device HT as a heat source. The supply of heat transfer medium TL from the heat storage device HT to the object to be heated Z can be determined based on the temperature of the storage space, the temperature of the external space, or the temperature of the water used for electrolysis, as with the operation of the sub-heater 21h'. This makes it possible to more reliably prevent freezing. If the hydrogen gas production facility is provided with water-cooled devices in addition to the rectifier 21', the heat stored in the heat storage device HT may be exhaust heat from such devices.

[0089] In the embodiments shown in Figures 8 and 9, a heat storage device HT is provided, and in the first ventilation mode, heat generated by heat-generating equipment is stored in the heat storage device HT, and in the second ventilation mode, the heat stored in the heat storage device HT is transferred to water to be kept warm, thereby preventing the water to be kept warm from freezing. In this embodiment, a relatively large amount of heat can be transferred to the water to be kept warm, and the amount of heat transferred can be easily controlled, so that freezing can be prevented more reliably.

[0090] As described above, in one embodiment of the present invention, Hydrogen gas production equipment, a water electrolysis device that electrolyzes water to generate hydrogen gas; and a wall that separates an accommodation space that accommodates the water electrolysis device from an external space; the water electrolysis device unit is provided with at least one heat-generating device that generates heat during operation, the wall portion is provided with a ventilation opening for discharging heat from the storage space to the external space by exhausting air from the storage space, and the ventilation opening includes a first ventilation opening and a second ventilation opening that is farther away from the heat-generating device than the first ventilation opening; Since it is possible to switch between a first ventilation mode in which ventilation between the storage space and the external space is performed by exhausting air from the first ventilation port, and a second ventilation mode in which ventilation is performed by exhausting air from the second ventilation port, it is easy to discharge heat from heat-generating equipment to the external space and the exhaust heat from the heat-generating equipment can be effectively used to prevent freezing.

[0091] According to a preferred aspect of this embodiment, The wall portion of the hydrogen gas production equipment comprises a first side wall and a second side wall that face each other across an accommodation space, the first ventilation port is provided in the first side wall, and the second ventilation port is provided in the second side wall. Therefore, in the hydrogen gas production equipment of this embodiment, when ventilation is performed in the first ventilation mode or the second ventilation mode, one of the first ventilation outlet and the second ventilation outlet can be used as an exhaust outlet and the other as an air intake port, making it easier to distribute new air introduced through the air intake port throughout the equipment and preventing the formation of areas where warm air or hydrogen gas can stagnate.

[0092] According to a preferred aspect of this embodiment, the water electrolysis device unit includes an electrolysis cell that receives power and electrolyzes water, and a rectifier that rectifies the power supplied to the electrolysis cell; The heat-generating device provided at a position closer to the first ventilation opening than to the second ventilation opening is the rectifier. Among the hydrogen gas production equipment, the rectifier is a heat generating device that generates a particularly large amount of heat, and therefore, according to this preferred embodiment, a particularly high effect can be obtained in preventing freezing.

[0093] According to a preferred aspect of this embodiment, The rectifier has a first exhaust port that exhausts toward the first ventilation port and a second exhaust port that exhausts toward the second ventilation port, and further has a shutter that opens and closes the second exhaust port. According to this preferred embodiment, it is easy to switch the direction of the rectifier's exhaust heat release between the first exhaust port and the second ventilation port, and it is easy to switch between discharging heat to the external space and effectively utilizing the heat in the storage space.

[0094] In a preferred aspect of this embodiment, the second exhaust port is disposed so that its position in the vertical direction is lower than the upper end of the heat-generating device. According to this preferred aspect, in the second ventilation mode, warm air around the heat-generating device can be drawn diagonally downward toward the second exhaust port, making it easier to heat areas near the floor that are prone to freezing.

[0095] According to a preferred aspect of this embodiment, Ventilation in the second ventilation mode is performed in multiple submodes; The plurality of sub-modes include at least one high ventilation sub-mode having a higher ventilation volume per unit time than the other sub-modes, and a low ventilation sub-mode having a lower ventilation volume per unit time than the high ventilation sub-mode. According to a further preferred aspect of the present embodiment, the low ventilation sub-mode is performed in a situation where the temperature of the external space is lower than that in the high ventilation sub-mode. According to such a preferred embodiment, the amount of air taken in from the outside space (ventilation rate) can be adjusted. Therefore, according to this preferred embodiment, the temperature inside the equipment can be maintained at an appropriate level even in a situation where the temperature in the external space is low and water inside the equipment may freeze.

[0096] According to a preferred aspect of this embodiment, the hydrogen gas production facility further includes an air conditioner that increases the temperature of the accommodation space. According to a preferred aspect of the present embodiment, the hydrogen gas production facility includes a pipe through which the water before electrolysis or the water after electrolysis flows, and further includes an antifreeze heater for heating the pipe. According to such a preferred embodiment, it is possible to prevent freezing even in unexpected situations where ventilation alone may not be enough to prevent freezing.

[0097] According to a preferred aspect of this embodiment, the hydrogen gas production facility includes piping through which the water before electrolysis or the water after electrolysis flows, the rectifier is water-cooled, and the piping is heated with a coolant heated by heat exchange in the rectifier. According to this preferred embodiment, the pipes can be directly heated with the coolant, so that pinpoint heating of areas where freezing is likely to occur can be easily performed.

[0098] In another embodiment of the present invention, A hydrogen gas production facility having a water electrolysis device that electrolyzes water to generate hydrogen gas, and a wall that separates an accommodation space that accommodates the water electrolysis device from an external space, the water electrolysis device unit is provided with at least one heat-generating device that generates heat during operation, a heat medium that is heated by the heat generated by the heat generating device; a plurality of heat exchangers including a first heat exchanger and a second heat exchanger for cooling the heat medium heated by the heat; Among the plurality of heat exchangers, the first heat exchanger is arranged so as to perform heat exchange in the accommodation space to cool the heat medium, and the second heat exchanger is arranged so as to perform heat exchange at a location in the accommodation space different from the first heat exchanger or to perform heat exchange in the external space to cool the heat medium, Since it is possible to switch between a first heat exchange mode in which heat is exchanged using the first heat exchanger and a second heat exchange mode in which heat is exchanged using the second heat exchanger, it is easy to discharge heat from heat-generating equipment to the outside space and the exhaust heat from the heat-generating equipment can be effectively used to prevent freezing.

[0099] According to a preferred aspect of this embodiment, the second heat exchanger is arranged so as to exchange heat in the external space and cool the heat medium, thereby making it possible to more reliably and easily discharge heat from heat-generating equipment into the external space.

[0100] The hydrogen gas production facility and the hydrogen gas production method of the present invention are not limited to the above-mentioned preferred embodiments. That is, the hydrogen gas production facility of the present invention is not limited to the above example in any way, and various modifications can be made to the above example within the scope that does not significantly impair the effects of the present invention. [Explanation of symbols]

[0101] 10: wall portion, 11: frame, 12: wall panel, 13: ventilation opening, 13a: first ventilation opening, 13b: second ventilation opening, 14: shutter, 15a': first ventilation fan, 15b: second ventilation fan, 15c: third ventilation fan, 20: water electrolysis device portion, 21, 21': rectifier, 21a, 21a': housing, 21b: cooling fan, 21za: shutter, 22: electrolysis device, 23: pure water production device, 24 : Pure water tank, 25: Water circulation pump, 26: (Anode side) gas-liquid separator, 27: Polisher, 28: Heat exchanger, 29: (Cathode side) gas-liquid separator, 30: Air conditioner, 100: Hydrogen gas production equipment, DC: Dehumidifier, DCa: Adsorption column, DP: Duct, HL: Hydrogen discharge path, L1: Water pipe, L2: Hydrogen gas pipe, L3: Oxygen gas pipe, OL: Oxygen discharge path, WL: Raw water supply path

Claims

1. A hydrogen gas production facility having a water electrolysis device that electrolyzes water to generate hydrogen gas, and a wall that separates an accommodation space that accommodates the water electrolysis device from an external space, The storage space contains water to be kept warm and which is heated to prevent freezing, the water electrolysis device unit is provided with at least one heat-generating device that generates heat during operation, a heat medium that is heated by the heat generated by the heat generating device; a plurality of heat exchangers including a first heat exchanger and a second heat exchanger for cooling the heat medium heated by the heat; Among the plurality of heat exchangers, the first heat exchanger is arranged so as to exchange heat with the water to be kept warm in the accommodation space to cool the heat medium, and the second heat exchanger is arranged so as to exchange heat at a location in the accommodation space different from the first heat exchanger or to exchange heat in the external space to cool the heat medium, A hydrogen gas production facility that can be switched between a first heat exchange mode in which heat exchange is performed using the first heat exchanger and a second heat exchange mode in which heat exchange is performed using the second heat exchanger, and in which the water to be kept warm is heated by the heat exchange in the first heat exchange mode.

2. 2. The hydrogen gas production facility according to claim 1, wherein the second heat exchanger is disposed so as to be able to cool the heat medium by heat exchange at a location in the accommodation space different from that of the first heat exchanger.

3. A hydrogen gas production facility having a water electrolysis device that electrolyzes water to generate hydrogen gas, and a wall that separates an accommodation space that accommodates the water electrolysis device from an external space, The storage space contains water to be kept warm and which is heated to prevent freezing, the water electrolysis device unit is provided with at least one heat-generating device that generates heat during operation, a heat medium that is heated by the heat generated by the heat generating device; a heat storage device that stores the heat of the heat medium, The hydrogen gas production facility heats the water to be kept warm by transferring the heat stored in the heat storage device to the water to be kept warm.

Images