JP7218245B2 - dehumidifier - Google Patents

Description

The present invention relates to a dehumidifier for removing moisture contained in gas.

2. Description of the Related Art Conventionally, a dehumidifier for removing moisture contained in hydrogen generated in a water electrolytic bath is known. In this type of dehumidifier, as described in Patent Document 1, a plurality of dehumidifiers containing an adsorbent capable of adsorbing moisture are arranged in parallel, and the hydrogen supply destination is alternately switched, so that one dehumidifier can While drying the hydrogen, a regeneration operation is performed in which the adsorbent whose dehumidification performance has deteriorated is heated and dried in another dehumidifier to regenerate it.

Regarding the control of the regeneration operation of such a dehumidifier, Patent Document 2 discloses that the moisture absorption rate of the adsorbent is calculated based on the dew point temperature of the dry hydrogen flowing through the output pipe of the dehumidifier, and the adsorbent is determined according to the moisture absorption rate. A technique has been proposed for controlling the temperature of a heater that heats the . According to the invention described in Patent Document 2, the regeneration operation is performed according to the moisture absorption rate of the adsorbent.

JP 2013-249488 A JP 2013-162647 A

(a) and (b) of FIG. 9 are schematic diagrams for explaining the flow of hydrogen flowing inside the dehumidifier 100, and (a) of FIG. 9 shows the flow of hydrogen during normal flow rate operation. , (b) of FIG. 9 shows the flow of hydrogen during low-flow operation. As shown in (a) of FIG. 9, in the case of normal operation in which the hydrogen flow rate is medium or high, hydrogen flows uniformly inside the dehumidifier 100, so the moisture absorption rate of the adsorbent A is substantially uniform. Become. On the other hand, in the case of low flow rate operation, hydrogen flows through a specific route (for example, the inner wall side) inside the dehumidifier 100, so only the adsorbent A around the specific route adsorbs moisture and the moisture absorption rate increases, and the adsorbent Variation occurs in the moisture absorption rate of A.

However, in the technique of Patent Document 2, regardless of the flow rate of hydrogen, if the dew point temperature of dry hydrogen increases, the moisture absorption rate is calculated according to the moisture absorption rate-dew point temperature relationship curve. Therefore, even though there are many adsorbents with a low moisture absorption rate, a high moisture absorption rate is calculated, and the temperature of the heater may be set higher than necessary. As a result, there is a problem that energy loss occurs during regeneration operation.

An object of one aspect of the present invention is to reduce energy loss during a regeneration operation for regenerating an adsorbent.

In order to solve the above problems, a dehumidifying apparatus according to an aspect of the present invention contains an adsorbent capable of adsorbing moisture, and dehumidifies wet gas supplied from a wet gas supply line to flow out dry gas. 1 dehumidifier, a calculation unit for calculating the moisture absorption rate of the adsorbent based on the flow rate and dew point temperature of the dry gas flowing out from the first dehumidifier, and the first dehumidifier according to the moisture absorption rate and a determination unit that determines operating conditions for a regeneration operation for regenerating the adsorbent housed in.

According to one aspect of the present invention, the operating conditions for the regeneration operation are determined according to the moisture absorption rate of the adsorbent calculated based on the flow rate of the dry gas and the dew point temperature. Therefore, it is possible to reduce the energy loss during the regeneration operation.

1 is a schematic diagram showing a hydrogen generator equipped with a dehumidifier according to an embodiment of the present invention; FIG. It is the schematic which shows the operation example of the adsorption|suction process which the said dehumidifier implements. It is the schematic which shows the operation example of the heating regeneration process which the said dehumidification apparatus implements. It is the schematic which shows the operation example of the cooling regeneration process which the said dehumidifier implements. (a) is a graph showing an example of the relationship between moisture absorption rate and regeneration time, (b) is a graph showing an example of the relationship between moisture absorption rate and heater temperature, and (c) is a graph showing an example of the relationship between moisture absorption rate and regeneration hydrogen flow rate. There is a graph showing an example of It is the schematic which shows the operation example of the pressure|voltage rise process which the said dehumidifier implements. It is the schematic which shows the operation example of the parallel process which the said dehumidifier implements. It is the schematic which shows the operation example of the switching process which the said dehumidifier implements. (a) and (b) are schematic diagrams for explaining the flow of hydrogen flowing through the inside of the dehumidifier, (a) showing the flow of hydrogen during normal flow rate operation, and (b) showing the flow of low flow rate Hydrogen flow during operation is shown.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 9. FIG. In this embodiment, an example of a hydrogen generator equipped with a dehumidifier according to the present invention will be described.

(Overview of hydrogen generator)
The hydrogen generator according to the present embodiment is an apparatus for producing dry hydrogen as a product gas by supplying hydrogen among hydrogen and oxygen generated in a water electrolyzer to a dehumidifier and dehumidifying it. The dry hydrogen produced is used as a fuel cell or other energy source. As will be described later, the hydrogen generator according to this embodiment calculates the moisture absorption rate of the adsorbent and performs optimal regeneration operation according to the moisture absorption rate, thereby reducing energy loss during regeneration operation.

(Configuration of hydrogen generator)
FIG. 1 is a schematic diagram showing a hydrogen generator 1 according to this embodiment. As shown in FIG. 1 , the hydrogen generator 1 includes a water electrolytic bath 2 , a pure water tank 3 , an oxygen gas-liquid separator 4 , a hydrogen gas-liquid separator 5 and a dehumidifier 6 .

The water electrolytic bath 2 electrolyzes water to generate hydrogen and oxygen. A pure water tank 3 for supplying pure water to the water electrolytic bath 2 is connected to the water electrolytic bath 2 . An ammeter Am1 is arranged in the water electrolytic bath 2 . The ammeter Am1 measures the value of the current supplied to the water electrolytic bath 2 . A current value detected by ammeter Am1 is output to control unit 64 via signal line SL1.

The water electrolytic bath 2 is also connected to an oxygen gas-liquid separator 4 and a hydrogen gas-liquid separator 5 . Oxygen generated by the electrolysis of water is supplied from the water electrolyzer 2 to the oxygen-gas-liquid separator 4 in the state of gas-liquid mixed water together with water remaining without being electrolyzed. On the other hand, the hydrogen generated by the electrolysis of water is supplied from the water electrolyzer 2 to the hydrogen-gas-liquid separator 5 in the state of gas-liquid mixed water together with the remaining water that has not been electrolyzed.

The oxygen-gas-liquid separator 4 separates the oxygen-containing gas-liquid mixed water supplied from the water electrolyzer 2 into oxygen and water. The water after the gas-liquid separation is supplied to the pure water tank 3 and reused as pure water. On the other hand, oxygen after gas-liquid separation is released to the atmosphere.

The hydrogen-gas-liquid separator 5 separates the hydrogen-containing gas-liquid mixed water supplied from the water electrolyzer 2 into hydrogen and water. Water after the gas-liquid separation is discharged outside as condensed water. On the other hand, the hydrogen after the gas-liquid separation is wet hydrogen (wet gas) containing a large amount of water. Therefore, the wet hydrogen after the gas-liquid separation is supplied to the dehumidifier 6 via the wet hydrogen supply line (wet gas supply line) L1, and water is removed.

The dehumidifier 6 dehumidifies the wet hydrogen supplied from the wet hydrogen supply line L1 to generate dry hydrogen (dry gas). The dehumidifier 6 includes a heat exchanger 61 , a first dehumidifier 62 , a second dehumidifier 63 and a controller 64 .

The heat exchanger 61 is arranged in the middle of the wet hydrogen supply line L1. The wet hydrogen generated by the hydrogen gas-liquid separator 5 is first cooled by the heat exchanger 61 to remove moisture to some extent, and then supplied to the first dehumidifier 62 or the second dehumidifier 63 . Thereby, the dehumidifying effect in the first dehumidifier 62 or the second dehumidifier 63 can be enhanced.

A thermometer T61 is arranged in the wet hydrogen supply line L1 on the downstream side of the heat exchanger 61 . A thermometer T61 detects the temperature of wet hydrogen flowing inside the wet hydrogen supply line L1. The temperature of wet hydrogen detected by thermometer T61 is output to control unit 64 via signal line SL2.

The first dehumidifier 62 and the second dehumidifier 63 are adsorption towers containing adsorbents capable of adsorbing moisture, such as synthetic zeolite particles, silica gel particles, and activated alumina particles. Although two dehumidifiers are provided in this embodiment, the number of dehumidifiers may be one or three or more.

The first dehumidifier 62 is supplied with wet hydrogen from the upstream side, and dehumidifies the wet hydrogen and causes dry hydrogen to flow out from the downstream side. Also, the second dehumidifier 63 is supplied with wet hydrogen from the upstream side, and dehumidifies the wet hydrogen and causes dry hydrogen to flow out from the downstream side.

The first dehumidifier 62 and the second dehumidifier 63 are arranged in parallel to alternately dehumidify wet hydrogen. That is, the dehumidifier 6 can switch the supply destination of wet hydrogen supplied from the wet hydrogen supply line L1 between the first dehumidifier 62 and the second dehumidifier 63 . In this embodiment, wet hydrogen from the wet hydrogen supply line L1 is supplied to the upstream side of the first dehumidifier 62 via the first automatic valve XV61. On the other hand, wet hydrogen from the wet hydrogen supply line L1 is supplied to the upstream side of the second dehumidifier 63 via the second automatic valve XV62.

The dehumidified dry hydrogen flowing out of the first dehumidifier 62 and the second dehumidifier 63 flows into the dry hydrogen supply line L2. In this embodiment, the dry hydrogen flowing out from the downstream side of the first dehumidifier 62 flows through the first check valve CV61 into the dry hydrogen supply line L2. On the other hand, the dry hydrogen flowing out from the downstream side of the second dehumidifier 63 flows through the second check valve CV62 into the dry hydrogen supply line L2. A portion of the dry hydrogen that has flowed into the dry hydrogen supply line L2 is used as regeneration gas for regenerating the adsorbent, and the remainder is supplied to the outside of the apparatus as product gas.

A flow meter F61, a dew point thermometer T62 and a pressure gauge P61 are arranged on the dry hydrogen supply line L2. The flow meter F61 detects the flow rate of dry hydrogen flowing through the dry hydrogen supply line L2. The dry hydrogen flow rate detected by the flow meter F61 is output to the control unit 64 via the signal line SL3. A dew point thermometer T62 detects the dew point temperature of the dry hydrogen flowing through the dry hydrogen supply line L2. The dew point temperature is the temperature at which condensation begins in a pressure environment when a gas containing moisture (water vapor) is cooled. From this dew point temperature and pressure, the moisture concentration (moisture content) of the gas can be obtained. The dew point temperature of dry hydrogen detected by dew point thermometer T62 is output to control unit 64 via signal line SL4. A pressure gauge P61 detects the pressure of dry hydrogen at the dew point measurement position. The pressure of the dry hydrogen detected by the pressure gauge P61 is output to the controller 64 via the signal line SL5. The installation position of the pressure gauge P61 may be upstream or downstream of the dew point thermometer T62 if the dew point measurement position and the pressure measurement position can be considered to match.

Note that the first dehumidifier 62 and the second dehumidifier 63 incorporate heaters (heating units) 62a and 63a, respectively. The first dehumidifier 62 and the second dehumidifier 63 heat the adsorbent that has adsorbed moisture with these heaters 62a and 63a to desorb moisture from the adsorbent and regenerate the adsorbent.

For example, the dehumidifier 6 supplies wet hydrogen from the wet hydrogen supply line L1 to the first dehumidifier 62 for dehumidification, and then switches the wet hydrogen supply destination from the first dehumidifier 62 to the second dehumidifier 63, The second dehumidifier 63 continues to dehumidify the wet hydrogen. Also, the dehumidifier 6 regenerates the adsorbent contained in the first dehumidifier 62 while continuing to dehumidify the wet hydrogen in the second dehumidifier 63 .

Specifically, the adsorbent contained in the first dehumidifier 62 is heated by the heater 62a, and part of the dry hydrogen flowing out of the second dehumidifier 63 is converted into a regeneration gas ( Hereinafter, it may be referred to as regenerated hydrogen.). That is, the dehumidifier 6 heats the adsorbent of the first dehumidifier 62 with the built-in heater 62a, introduces regenerated hydrogen from the downstream side of the first dehumidifier 62, and removes the moisture separated from the adsorbent. The adsorbent is regenerated by being accompanied with regenerated hydrogen.

This regenerated hydrogen is supplied to the first dehumidifier 62 or the second dehumidifier 63 via a regenerated hydrogen supply line L3 connected to the dry hydrogen supply line L2 on the downstream side of the dew point thermometer T62. A flow control valve V61 is arranged in the regenerated hydrogen supply line L3. When regenerated hydrogen is supplied to the first dehumidifier 62, part of the dry hydrogen flowing through the dry hydrogen supply line L2 is sent to the downstream side of the first dehumidifier 62 via the flow control valve V61 and the third check valve CV63. influx. On the other hand, when regenerated hydrogen is supplied to the second dehumidifier 63, part of the dry hydrogen flowing through the dry hydrogen supply line L2 is downstream of the second dehumidifier 63 via the flow control valve V61 and the fourth check valve CV64. flow to the side.

The regenerated hydrogen after use, which has become wet with water, flows out from the upstream side of the first dehumidifier 62 or the second dehumidifier 63, passes through the third automatic valve XV63 or the fourth automatic valve XV64, and becomes regenerated hydrogen. It flows into the exhaust line L4 and is released to the atmosphere.

The control unit 64 controls the operation of the dehumidifier 6 as a whole. The control unit 64 includes a calculation unit 641 , a determination unit 642 and a device control unit 643 .

The calculation unit 641 calculates the moisture absorption rate of the adsorbent contained in the first dehumidifier 62 and the second dehumidifier 63 . The calculation unit 641 calculates the value of the current supplied to the water electrolyzer 2 detected by the ammeter Am1, the temperature of wet hydrogen detected by the thermometer T61, the flow rate of dry hydrogen detected by the flow meter F61, and the dew point thermometer. The dew point temperature of dry hydrogen detected by T62 and the pressure of dry hydrogen detected by pressure gauge P61 are stored in a memory (not shown), and the moisture absorption rate of the adsorbent is calculated using these historical data. The details of the processing for calculating the moisture absorption rate of the adsorbent will be described later. The calculation unit 641 outputs the calculated moisture absorption rate of the adsorbent to the determination unit 642 .

The determination unit 642 determines operating conditions for regeneration operation for regeneration of the adsorbent performed by the first dehumidifier 62 and the second dehumidifier 63 according to the moisture absorption rate of the adsorbent obtained from the calculation unit 641 . The operating conditions refer to various parameters necessary for controlling regeneration operation. The operating conditions determined by the determining unit 642 include, for example, the operating time of the regeneration operation, the temperature of the heaters 62a and 63a, the flow rate of the regenerated hydrogen, and the like. The determination unit 642 outputs the determined operating conditions for regeneration operation to the device control unit 643 .

The device control section 643 controls the operation of each mechanism included in the dehumidifier 6 . For example, the device control unit 643 switches the wet hydrogen supply destination between the first dehumidifier 62 and the second dehumidifier 63 based on the dew point temperature of the dry hydrogen acquired from the dew point thermometer T62. The device control unit 643 also controls the regeneration operation of the first dehumidifier 62 and the second dehumidifier 63 based on the operating conditions for the regeneration operation acquired from the determination unit 642 .

(Operation example of dehumidifier)
Next, an operation example of the dehumidifier 6 will be described with reference to FIGS. 2 to 8. FIG. The dehumidifier 6 according to this embodiment performs an adsorption process, a regeneration process, a cooling process, and a tower switching process.

FIG. 2 is a schematic diagram showing an operation example of the adsorption step performed by the dehumidifier 6. As shown in FIG. FIG. 2 shows a state in which the first dehumidifier 62 is in adsorption (dehumidification) operation and the second dehumidifier 63 is out of operation.

As shown in FIG. 2, in the adsorption step, the wet hydrogen A1 flowing through the wet hydrogen supply line L1 is first cooled by the heat exchanger 61 to remove some moisture, and then supplied to the first dehumidifier 62. In the adsorption step, the first automatic valve XV61 is opened, and the second automatic valve XV62, third automatic valve XV63 and fourth automatic valve XV64 are closed. As a result, the wet hydrogen A1 flows into the upstream side of the heat exchanger 61 through the first automatic valve XV61. The wet hydrogen A1 that has flowed in from the upstream side of the first dehumidifier 62 is dehumidified by the adsorbent contained in the first dehumidifier 62 . The dry hydrogen A2 after dehumidification flows out from the downstream side of the first dehumidifier 62, flows into the dry hydrogen supply line L2 through the first check valve CV61, and is supplied to the outside of the apparatus as product gas.

In the next regeneration step, the dehumidifier 6 switches the supply destination of the wet hydrogen A1 to the second dehumidifier 63 based on the dew point temperature of the dry hydrogen A2 detected by the dew point thermometer T62. While continuing the dehumidification process, the adsorbent contained in the first dehumidifier 62 is regenerated.

Specifically, the dew point temperature (detected value) of the dry hydrogen A2 detected by the dew point thermometer T62 is the detection dew point temperature T ₀ , and the dew point temperature ( When the set value) is defined as the switching dew _point temperature T1, the dehumidifier 6 selects the supply destination of the wet hydrogen A1 as the _first dehumidifying device when the detected dew point temperature _T0 reaches the switching dew point temperature T1 in the adsorption step. The dehumidifier 62 is switched to the second dehumidifier 63.

That is, the equipment control section 643 constantly monitors the detected dew point temperature _T0 of the dry hydrogen A2 detected by the dew point thermometer T62 so that the detected dew _point temperature _T0 <switching dew point temperature T1. Then, when the detected dew point temperature T ₀ becomes equal to the switching dew point temperature T ₁ , the supply destination of the wet hydrogen A1 is switched from the first dehumidifier 62 to the second dehumidifier 63, and the regeneration process is performed.

Note that when the upper limit value ₍ guaranteed value) of the dew point temperature required for the product gas to be manufactured is defined as the guaranteed dew point temperature T2, the switching dew _point temperature T1 is set so that switching dew point temperature T1 < guaranteed _{dew point} temperature T2. , is appropriately set according to the guaranteed _dew point temperature T2. For example, when producing a product gas with _a guaranteed dew point temperature T2 of -66° _C , the switching dew point temperature T1 is set to -68°C to -69°C, which is ₂ °C to 3°C lower than the guaranteed dew point temperature T2.

This regeneration step includes a heating regeneration step and a cooling regeneration step. FIG. 3 is a schematic diagram showing an operation example of the heating regeneration process performed by the dehumidifier 6. As shown in FIG. FIG. 3 shows a state in which the first dehumidifier 62 is in heat regeneration operation and the second dehumidifier 63 is in adsorption operation.

As shown in FIG. 3, in the heating regeneration step, wet hydrogen A1 is supplied to the upstream side of the second dehumidifier 63, and part of the dry hydrogen A2 flowing out from the downstream side of the second dehumidifier 63 is regenerated hydrogen. The line is switched so that it is supplied to the downstream side of the first dehumidifier 62 as A3. This line switching is performed by the device control unit 643 controlling the opening and closing of the first automatic valve XV61, the second automatic valve XV62, the third automatic valve XV63, the fourth automatic valve XV64, and the flow control valve V61 (line switching mechanism). Then, while the heater 62a built in the first dehumidifier 62 is turned on to heat the adsorbent of the first dehumidifier 62, the regenerated hydrogen A3 supplied from the downstream side of the first dehumidifier 62 is circulated. , to dry the sorbent.

Specifically, in the heating regeneration step, the second automatic valve XV62 and the third automatic valve XV63 are opened, and the first automatic valve XV61 and the fourth automatic valve XV64 are closed. As a result, the wet hydrogen A1 flows from the upstream side of the second dehumidifier 63 through the second automatic valve XV62. The dry hydrogen A2 after dehumidification flows out from the downstream side of the second dehumidifier 63, passes through the second check valve CV62, and flows into the dry hydrogen supply line L2. In addition, in the heating regeneration process, the flow control valve V61 is opened. As a result, part of the dry hydrogen A2 that has flowed into the dry hydrogen supply line L2 flows into the regenerated hydrogen supply line L3, passes through the flow rate adjustment valve V61 and the third check valve CV63, and flows into the downstream side of the first dehumidifier 62. do.

Thus, in the heating regeneration step, the regenerated hydrogen A3 is supplied to the downstream side of the first dehumidifier 62, and the adsorbent of the first dehumidifier 62 is heated to 150° C. to 200° C. by the built-in heater 62a. Moisture in the adsorbent is allowed to accompany the regenerated hydrogen A3. Thereby, the adsorbent can be efficiently dried and regenerated. The regenerated hydrogen A4 after use, which has become wet with water, flows out from the upstream side of the first dehumidifier 62, passes through the third automatic valve XV63, flows into the regenerated hydrogen exhaust line L4, and enters the atmosphere. released.

In the subsequent cooling regeneration step, the adsorbent heated to a high temperature by the heating regeneration step is cooled by the regeneration hydrogen A3. FIG. 4 is a schematic diagram showing an operation example of the cooling regeneration process performed by the dehumidifier 6. As shown in FIG. FIG. 4 shows a state in which the first dehumidifier 62 is in cooling regeneration operation and the second dehumidifier 63 is in adsorption operation.

As shown in FIG. 4, in the cooling regeneration step, the heater 62a built in the first dehumidifier 62 is turned off, and the regenerated hydrogen A3 continues to flow through the first dehumidifier 62. As shown in FIG. Thereby, the inside of the first dehumidifier 62 is cooled by the regenerated hydrogen A3.

The operating conditions for the regeneration operation performed in the regeneration step described above are determined according to the moisture absorption rate of the adsorbent of the first dehumidifier 62 . The process of calculating the moisture absorption rate of this adsorbent is executed by the calculation unit 641 as follows when the supply destination of the wet hydrogen A1 is switched from the first dehumidifier 62 to the second dehumidifier 63.

First, the calculation unit 641 calculates the “integrated amount of inflowing water”, which is the integrated amount (total amount) of water contained in the wet hydrogen A1 that has flowed into the first dehumidifier 62 in the adsorption step, and The "integrated amount of outflow water", which is the integrated amount (total amount) of water contained in the dry hydrogen A2 that has flowed out from 62, is calculated.

The "accumulated amount of inflowing moisture" is obtained by time-integrating the product of the "inflow flow rate" and the "water concentration" of the wet hydrogen A1 that has flowed into the first dehumidifier 62 in the adsorption step. The "integrated outflow water content" is obtained by time-integrating the product of the "outflow flow rate" of the dry hydrogen A2 flowing in from the first dehumidifier 62 in the adsorption step and the "water concentration". Therefore, the "integrated inflow water amount" and the "integrated outflow water amount" are obtained by, for example, the following calculation formulas (1) and (2).
Time integral of integrated inflow water content = (inflow flow rate x moisture concentration of wet hydrogen) (1)
Time integral of integrated outflow water content = (outflow flow rate x moisture concentration of dry hydrogen) (2)
The "inflow flow rate" and the "outflow flow rate" in the above calculation formulas (1) and (2) have the same value. This is because in the adsorption step, the flow rate of the wet hydrogen A1 flowing into the upstream side of the first dehumidifier 62 and the flow rate of the dry hydrogen A2 flowing out of the downstream side of the first dehumidifier 62 are substantially the same. be. Therefore, the calculation unit 641 reads from the memory the history data of the flow rate of the dry hydrogen A2 detected by the flow meter F61 in the adsorption step, and based on the history data, calculates the "inflow Calculate the "flow rate" and the "outflow rate". Further, the calculation unit 641 reads from the memory the history data of the temperature of the wet hydrogen A1 detected by the thermometer T61 in the adsorption step, identifies the saturated water vapor amount based on the history data, and calculates the above calculation formula (1). Calculate the "moisture concentration of wet hydrogen". Further, in the adsorption step, the calculation unit 641 reads the history data of the dew point temperature of the dry hydrogen A2 detected by the dew point thermometer T62 and the pressure of the dry hydrogen A2 detected by the pressure gauge P61, and based on the history data, to determine the water concentration, and obtain the "water concentration of dry hydrogen" in the above formula (2).

Note that the calculation unit 641 calculates the "moisture concentration of the wet hydrogen" of the above calculation formula (1) based on the design cooling temperature of the heat exchanger 61 instead of the temperature of the wet hydrogen A1 detected by the thermometer T61. you may ask. Alternatively, the calculation unit 641 acquires the temperature of the pure water electrolyzed in the water electrolysis tank 2 from a thermometer (not shown) instead of the temperature of the wet hydrogen A1, and based on the temperature of the pure water, the above calculation formula The "moisture concentration of wet hydrogen" in (1) may be obtained. That is, the temperature used to calculate the "moisture concentration of wet hydrogen" is not particularly limited as long as it is a temperature at which the "moisture concentration of wet hydrogen" can be estimated.

Further, the calculation unit 641 may obtain the "inflow flow rate" of the above formula (1) based on the current value detected by the ammeter Am1. In this case, the amount of wet hydrogen A1 generated in the electrolysis of the water electrolyzer 2 may be calculated based on the value of the current that is supplied to the water electrolyzer 2 . Alternatively, the calculation unit 641 may obtain the "inflow flow rate" of the above formula (1) using a measuring instrument such as a mass flow meter.

Next, the calculation unit 641 obtains the "moisture absorption amount of the adsorbent" using the "integrated inflow water amount" and "integrated outflow water amount" obtained by the above calculation formulas (1) and (2). This "moisture absorption amount of the adsorbent" is obtained by, for example, the following formula (3).
Moisture absorption amount of adsorbent = Cumulative inflow water amount - Cumulative outflow water amount (3)
The "moisture absorption amount of the adsorbent" in the formula (3) indicates the amount (total amount) of moisture adsorbed by the adsorbent in the adsorption step. The calculation unit 641 substitutes the values of the "integrated inflow water content" and "integrated outflow water content" obtained by the above calculation formulas (1) and (2) into the above calculation formula (3), thereby obtaining the above "adsorbent Calculate the "moisture absorption amount".

Finally, the calculation unit 641 obtains the "moisture absorption rate of the adsorbent" using the "moisture absorption amount of the adsorbent" obtained by the above formula (3). This "moisture absorption rate of the adsorbent" is obtained by, for example, the following formula (4).
Moisture absorption rate of adsorbent = (moisture absorption amount of adsorbent/designed maximum moisture absorption amount of adsorbent) * 100 (4)
The "designed maximum moisture absorption amount of the adsorbent" in the above formula (4) is a value determined when the dehumidifier is designed. The calculation unit 641 calculates the "moisture absorption rate of the adsorbent" by substituting the "moisture absorption amount of the adsorbent" obtained by the above formula (3) into the above formula (4). The calculation unit 641 outputs the calculated moisture absorption rate of the adsorbent to the determination unit 642 .

The determination unit 642 determines the operating conditions for the regeneration operation performed by the first dehumidifier 62 according to the moisture absorption rate of the adsorbent obtained from the calculation unit 641 . The operating conditions include at least one of the operating time of the regeneration operation, the heating temperature of the heater 62 a of the first dehumidifier 62 and the flow rate of the regenerated hydrogen A3 supplied to the first dehumidifier 62 .

FIG. 5(a) is a graph showing an example of the relationship between the moisture absorption rate and the operation time of the regeneration operation (regeneration time), and FIG. 5(b) is a graph showing an example of the relationship between the moisture absorption rate and the heater temperature. , and FIG. 5(c) is a graph showing an example of the relationship between the moisture absorption rate and the regenerated hydrogen flow rate.

As shown in (a) of FIG. 5, the determining unit 642 increases the operation time (regeneration time) of the regeneration operation of the first dehumidifier 62 as the moisture absorption rate of the adsorbent approaches 100% saturation. Determine the operating conditions as follows. Alternatively, as shown in FIG. 5B, the determining unit 642 operates so that the temperature of the heater 62a of the first dehumidifier 62 increases as the moisture absorption rate of the adsorbent approaches 100% saturation. Determine conditions. Alternatively, as shown in (c) of FIG. 5, the determination unit 642 increases the flow rate of the regenerated hydrogen A3 flowing into the first dehumidifier 62 as the moisture absorption rate of the adsorbent approaches 100% saturation. Determine the operating conditions as follows. The determination unit 642 outputs the determined operating conditions for regeneration operation to the device control unit 643 .

The device control unit 643 performs regeneration operation of the first dehumidifier 62 based on the operating conditions acquired from the determination unit 642 .

Thus, the dehumidifier 6 determines the operating conditions for the regeneration operation according to the moisture absorption rate of the adsorbent calculated based on the flow rate of the dry hydrogen A2, the dew point temperature, and the like. Therefore, compared to the conventional configuration in which the moisture absorption rate of the adsorbent is calculated based only on the dew point temperature, the moisture absorption rate of the adsorbent can be calculated more accurately and the operating conditions for the regeneration operation can be determined. Therefore, it is possible to reduce the energy loss during the regeneration operation for regenerating the adsorbent.

In the next tower switching step, the operation of the first dehumidifier 62 that has completed the regeneration step and the operation of the second dehumidifier 63 that has performed the dehumidification step is switched. The tower switching step is carried out when the dew point temperature reaches or exceeds a predetermined reference dew point temperature. This tower switching process includes a pressurization process, a parallel process and a switching process.

6A and 6B are schematic diagrams showing an operation example of the pressurizing step performed by the dehumidifier 6. FIG. FIG. 6 shows a state in which the first dehumidifier 62 is in boosting operation and the second dehumidifier 63 is in adsorption operation.

As shown in FIG. 6, in the pressurizing step, the second automatic valve XV62 is opened, and the first automatic valve XV61, the third automatic valve XV63 and the fourth automatic valve XV64 are closed. Further, the flow control valve V61 is opened so that the regenerated hydrogen A3 is supplied to the downstream side of the first dehumidifier 62 through the regenerated hydrogen supply line L3. At this time, since the third automatic valve XV63 is closed, the internal pressure of the first dehumidifier 62 rises, and the pressures of the first dehumidifier 62 and the second dehumidifier 63 become substantially equal. By equalizing the pressures of the first dehumidifier 62 and the second dehumidifier 63 , it is possible to prevent the adsorbent from flowing due to rapid pressurization of the first dehumidifier 62 .

FIG. 7 is a schematic diagram showing an operation example of a parallel process performed by the dehumidifier 6. FIG. FIG. 7 shows a state in which the first dehumidifier 62 and the second dehumidifier 63 are in adsorption operation. In the parallel process, both the first dehumidifier 62 and the second dehumidifier 63 are temporarily operated for adsorption.

As shown in FIG. 7, in the parallel process, the first automatic valve XV61 and the second automatic valve XV62 are opened, and the third automatic valve XV63 and the fourth automatic valve XV64 are closed. Thereby, wet hydrogen A1 is supplied to the first dehumidifier 62 and the second dehumidifier 63 .

FIG. 8 is a schematic diagram showing an operation example of the switching process performed by the dehumidifier 6. As shown in FIG. FIG. 8 shows a state in which the first dehumidifier 62 is in adsorption operation and the second dehumidifier 63 is in regeneration operation. In the switching step, the supply destination of wet hydrogen A1 is switched only to the first dehumidifier 62 .

As shown in FIG. 8, in the switching process, the first automatic valve XV61 and the fourth automatic valve XV64 are opened, and the second automatic valve XV62 and the third automatic valve XV63 are closed. As a result, the wet hydrogen A1 flows into the upstream side of the first dehumidifier 62 via the first automatic valve XV61. The dry hydrogen A2 after dehumidification flows out from the downstream side of the first dehumidifier 62, passes through the first check valve CV61, and flows into the dry hydrogen supply line L2.

Also, in the switching process, the flow control valve V61 is opened. As a result, part of the dry hydrogen A2 that has flowed into the dry hydrogen supply line L2 flows in as regenerated hydrogen A3 from the downstream side of the second dehumidifier 63, and the regeneration process described above is performed in the second dehumidifier 63.

In addition, in the present embodiment, the configuration for dehumidifying by supplying hydrogen among the hydrogen and oxygen generated in the water electrolytic bath 2 to the dehumidifier 6 has been described. However, the type of wet gas (processed gas) dehumidified by the dehumidifier 6 is not limited to hydrogen. The wet gas may be any gas containing moisture, and may be oxygen or other gases (gases).

The present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. is also included in the technical scope of the present invention.

(summary)
A dehumidifying apparatus according to aspect 1 of the present invention includes a first dehumidifier that houses an adsorbent capable of adsorbing moisture and dehumidifies a wet gas supplied from a wet gas supply line to flow out a dry gas; and the first dehumidifier. a calculation unit for calculating the moisture absorption rate of the adsorbent based on the flow rate and dew point temperature of the dry gas flowing out from the device; and a regeneration operation of the first dehumidifier for regenerating the adsorbent according to the moisture absorption rate. and a determination unit that determines the operating conditions of the

According to the above configuration, the dehumidifier determines the operating conditions for the regeneration operation according to the moisture absorption rate of the adsorbent calculated based on the flow rate of the dry gas and the dew point temperature. Therefore, compared to the conventional configuration in which the moisture absorption rate of the adsorbent is calculated based only on the dew point temperature, the moisture absorption rate of the adsorbent can be calculated more accurately and the operating conditions for the regeneration operation can be determined. Therefore, it is possible to reduce the energy loss during the regeneration operation for regenerating the adsorbent.

Further, the dehumidifier according to aspect 2 of the present invention is the dehumidifier according to aspect 1, which is connected in parallel with the first dehumidifier that contains an adsorbent capable of adsorbing moisture and outputs dry gas obtained by dehumidifying the wet gas. a second dehumidifier, switching the supply destination of the wet gas from the first dehumidifier to the second dehumidifier based on the dew point temperature, and part of the dry gas flowing out from the second dehumidifier It further comprises a line switching mechanism for supplying regeneration gas for regenerating the adsorbent contained in the first dehumidifier to the first dehumidifier.

According to the above configuration, the supply destination of the wet gas is switched from the first dehumidifier to the second dehumidifier based on the dew point temperature, and the second dehumidifier continues to dehumidify the wet gas while the first dehumidifier accommodates it. The adsorbent used can be regenerated.

Further, in the dehumidifier according to aspect 3 of the present invention, in aspect 2, the first dehumidifier includes a heating unit that heats the adsorbent during the regeneration operation, and the operating condition includes the regeneration operation operation time, heating temperature of the heating unit, and at least one of the flow rate of the regeneration gas supplied to the first dehumidifier.

According to the above configuration, at least one of the operation time of the regeneration operation, the heating temperature of the heating unit, and the amount of regeneration gas supplied to the first dehumidifier is determined according to the moisture absorption rate of the adsorbent. Therefore, it is possible to determine the optimum operating conditions according to the moisture absorption rate of the adsorbent.

The dehumidifier according to aspect 4 of the present invention is the aspect 1 to 3, wherein the calculation unit integrates moisture contained in the dry gas flowing out from the first dehumidifier based on the flow rate and the dew point temperature. The cumulative amount of outflowing water is obtained, and the moisture absorption rate is calculated using the cumulative amount of outflowing water.

According to the above configuration, the moisture absorption rate of the adsorbent accommodated in the first dehumidifier is preferably calculated using the integrated outflow moisture amount, which is the integrated amount of moisture contained in the dry gas that has flowed out from the first dehumidifier. can do.

A dehumidifier according to aspect 5 of the present invention is the dehumidifier according to aspect 4, wherein the calculating unit comprises an integrated inflow moisture amount, which is an integrated amount of moisture contained in the wet gas that has flowed into the first dehumidifier, and an integrated outflow moisture amount. Based on the difference from the amount, the amount of moisture absorbed, which is the amount of moisture adsorbed by the adsorbent, is further obtained, and the moisture absorption is calculated using the amount of moisture absorbed.

According to the above configuration, it is possible to accurately and easily calculate the moisture absorption rate of the adsorbent by using the moisture absorption amount, which is the amount of water adsorbed by the adsorbent contained in the first dehumidifier.

1: hydrogen generator 2: water electrolytic bath 6: dehumidifier 62: first dehumidifier 62a: heater (heating unit)
63: Second dehumidifier 63a: Heater (heating unit)
64: Control unit 641: Calculation unit 642: Determination unit 643: Equipment control unit A1: Wet hydrogen (wet gas)
A2: Dry hydrogen (dry gas)
A3: Regenerated hydrogen (regenerated gas)
L1: wet hydrogen supply line (wet gas supply line)
L2: Dry hydrogen supply line (dry gas supply line)
F61: flow meter T62: dew point thermometer

Claims (3)

a first dehumidifier that houses an adsorbent capable of adsorbing moisture and that dehumidifies the wet gas supplied from the wet gas supply line and causes a dry gas to flow out;
a calculation unit that calculates the moisture absorption rate of the adsorbent based on the flow rate , dew point temperature and pressure of the dry gas flowing out from the first dehumidifier;
a determination unit that determines operating conditions for a regeneration operation for regenerating the adsorbent contained in the first dehumidifier according to the moisture absorption rate;
with
The calculation unit is
Using the following formula (1), obtain an integrated amount of inflowing moisture, which is an integrated amount of moisture contained in the wet gas that has flowed into the first dehumidifier,
Cumulative inflow moisture amount = Time integration of (inflow flow rate x moisture concentration of wet gas) (1)
The integrated amount of moisture contained in the dry gas flowing out from the first dehumidifier based on the flow rate and the moisture concentration of the dry gas obtained from the dew point temperature and the pressure by the following formula (2). Calculate the integrated outflow water content,
Cumulative outflow water content = Time integration of (outflow flow rate x moisture concentration of dry gas) (2)
Based on the difference between the integrated inflow water amount and the integrated outflow water amount, the moisture absorption amount, which is the amount of water adsorbed by the adsorbent, is calculated by the following formula (3),
Moisture absorption amount of adsorbent = Cumulative inflow water amount - Cumulative outflow water amount (3)
Calculate the moisture absorption rate using the moisture absorption amount according to the following formula (4).
Moisture absorption rate of adsorbent = (moisture absorption amount of adsorbent/designed maximum moisture absorption amount of adsorbent) * 100 (4)
dehumidifier. a second dehumidifier connected in parallel with the first dehumidifier, which houses an adsorbent capable of adsorbing moisture and outputs dry gas obtained by dehumidifying the wet gas;
The supply destination of the wet gas is switched from the first dehumidifier to the second dehumidifier based on the dew point temperature, and part of the dry gas flowing out from the second dehumidifier is stored in the first dehumidifier. a line switching mechanism for supplying the first dehumidifier as a regeneration gas for regenerating the adsorbent;
The dehumidifier of claim 1, further comprising: The first dehumidifier includes a heating unit that heats the adsorbent during the regeneration operation,
3. The dehumidifier according to claim 2, wherein the operating conditions include at least one of an operating time of the regeneration operation, a heating temperature of the heating unit, and a flow rate of the regeneration gas supplied to the first dehumidifier.

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