JP4159220B2 - Absorption refrigerator hydrogen gas removal device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hydrogen gas removing device for an absorption refrigerator.
[0002]
[Prior art]
In absorption refrigerators, when hydrogen gas H ₂ is generated due to corrosion of metal bodies in the working fluid system (refrigerant and absorption liquid circulation system) and accumulates, the internal pressure of the absorber and evaporator rises. since the refrigerating performance is reduced by, it is necessary to remove the generated hydrogen gas H _2, conventionally, the vessel inside pressure of the absorber and the evaporator to remove the generated hydrogen gas H ₂ to keep low The following means (a) to (d) were taken.
[0003]
(A) The working fluid system of the absorption refrigerator is evacuated again using a vacuum pump during regular maintenance.
(B) A vacuum tank is connected to the working fluid system of the absorption refrigeration machine via an on-off valve, and the hydrogen gas H ₂ collected by the gas-liquid separation process for the working fluid is sequentially supplied to the vacuum tank by the on-off valve operation. Accommodate.
(C) The hydrogen storage alloy stores the hydrogen gas H ₂ in the working fluid system.
(D) The hydrogen gas H ₂ of the working fluid system in the absorption refrigerator is discharged out of the system by a hydrogen partial pressure difference through a palladium cell that allows permeation of the hydrogen gas H ₂ .
[0004]
[Problems to be solved by the invention]
However, each of the means (a) to (d) has the following problems.
[0005]
With the means (a), the burden of maintenance work is large, and when the absorption refrigerator becomes old, the necessary frequency of maintenance increases and the burden is further increased.
In the means (b), since there is a limit to the amount of hydrogen gas contained in the evacuated tank, maintenance for evacuating the evacuated tank regularly is also necessary. Increasing the capacity increases the size of the absorption refrigerator.
With the means (c), since the hydrogen storage capacity of the hydrogen storage alloy is limited, maintenance is required to periodically replace the hydrogen storage alloy, and the hydrogen storage alloy is oxidized when exposed to the atmosphere. The hydrogen storage function is lost, making it difficult to handle.
In the means (d), hydrogen gas permeation in the palladium cell is performed in a form accompanied by a change in the lattice constant of palladium (that is, distortion of the crystal structure), so that the palladium cell is easily damaged by fatigue (generally 2 to 2). (5 year life), and palladium is expensive, increasing the cost of equipment and replacement of cells.
[0006]
In view of this situation, the main problem of the present invention is to provide a hydrogen gas removal device for an absorption refrigeration machine that can effectively solve the above-described problems in the conventional means by adopting a rational hydrogen gas removal method. In the point.
[0007]
[Means for Solving the Problems]
[1] In the invention according to claim 1,
A cell is formed by sandwiching an oxygen ion conductor between the porous hydrogen side electrode and the porous oxygen side electrode,
This cell is placed in a state where the hydrogen side electrode faces the hydrogen gas removal target space on the working fluid system side in the absorption refrigerator and the oxygen side electrode faces the atmospheric space,
The conductive circuit connecting the hydrogen side electrode and the oxygen side electrode has a configuration in which a direct current power source for controlling ion conduction is applied to apply a voltage to both electrodes with the hydrogen side electrode serving as a negative electrode.
[0008]
In other words, according to this configuration, by applying an appropriate voltage to both electrodes from the DC power source, oxygen ions O moving inside the oxygen ion conductor as a solid electrolyte from the atmospheric space through the porous oxygen side electrode. ^2- (oxide ion) and hydrogen gas H ₂ in the hydrogen gas removal target space are reacted at the hydrogen side electrode as shown in the following formula (c),
H ₂ + O ²⁻ → H ₂ O + 2e ⁻ (c)
Thereby, hydrogen gas H ₂ existing in the space can be efficiently removed from the hydrogen gas removal target space on the working fluid system side in the absorption refrigerator in the form of water molecules H ₂ O.
[0009]
Then, by removing the hydrogen gas H ₂ by this method, it is not necessary to perform heavy maintenance such as evacuation again or replacement of the hydrogen storage alloy as in the conventional means (a) to (c) described above. While avoiding the enlargement of the airframe by the equipment of a large vacuum tank as in the conventional means (b) and the difficulty in handling as in the conventional means (c) using a hydrogen storage alloy, the absorption type It is possible to effectively prevent an increase in the internal pressure of the absorber and the evaporator due to the generation of hydrogen gas in the working fluid system in the refrigerator, so that the refrigeration capacity of the absorption refrigerator can be maintained permanently high.
[0010]
In addition, oxygen ion conductors (eg, stabilized zirconia) can move oxygen ions O ²⁻ without changing the lattice constant, so that hydrogen gas H ₂ permeates palladium through changes in the lattice constant. Compared with the conventional means (d), the device durability is far superior, and since oxygen ion conductors are generally available at a lower cost than palladium, the device cost is also advantageous.
[0011]
In addition, when the oxygen ion passage resistance of the oxygen ion conductor to be used is large, it is desirable to additionally provide a heating means for heating the oxygen ion conductor to reduce the passage resistance of oxygen ions O ²⁻ , In the case of using an oxygen ion conductor having a relatively small oxygen ion passage resistance, such as the one described above, such additional equipment of the heating means is not necessarily required.
[0012]
[2] In the invention according to claim 2, in carrying out the invention according to claim 1,
The voltage applied by the DC power supply is set to a value at which both the hydrogen partial pressure and the oxygen partial pressure in the hydrogen gas removal target space are kept below their allowable upper limit values.
[0013]
In other words, the voltage applied by the DC power source functions to limit the amount of oxygen ion passing through the oxygen ion conductor to an appropriate amount. Therefore, as the applied voltage is reduced, the hydrogen gas to the hydrogen gas removal target space is reduced. Although the hydrogen partial pressure in the hydrogen gas removal target space can be lowered by increasing the removal capability, on the other hand, if the applied voltage is excessively small, the reaction of the following formula (D) becomes noticeable at the hydrogen side electrode,
^{_{2O 2- → O 2 + 4e -}} ...... ( d)
The amount of oxygen gas generated at the hydrogen side electrode increases, and the oxygen partial pressure in the hydrogen gas removal target space tends to increase.
[0014]
This increase in the oxygen partial pressure causes the internal pressure of the absorber and the evaporator to increase as in the case of the increase in the hydrogen partial pressure due to the generation of hydrogen gas in the working fluid system in the absorption refrigerator.
[0015]
From this, as described above, as the voltage applied by the DC power source, the voltage value that maintains both the hydrogen partial pressure and the oxygen partial pressure in the hydrogen gas removal target space below the allowable upper limit values (that is, the oxygen partial pressure is If a voltage value that is equal to or higher than the allowable upper limit value and the hydrogen partial pressure is equal to or lower than the allowable upper limit value) is adopted, the oxygen gas generation at the hydrogen side electrode is reversed. While avoiding the inconvenience of rising pressure, it is possible to prevent the rise in the internal pressure of the absorber and evaporator due to the generation of hydrogen gas in the working fluid system in the absorption refrigeration machine. It is possible to achieve the intended purpose of maintaining a high level of energy more reliably.
[0016]
[3] In carrying out the invention according to claim 2, in the invention according to claim 3,
The applied voltage E by the DC power source is set to a value satisfying both the following formulas (a) and (b).
E ≦ Eo + (RT / 2F) ln [Ps / (Poo ^1/2 · Ph)] …… (I)
E ≧ (RT / 4F) ln (Poo / Poi) (b)
Here, Eo: standard potential of reaction in which water is generated from oxygen and hydrogen R: gas constant T: absolute temperature F: Faraday constant Ps: partial pressure of water vapor in hydrogen gas removal target Poo: partial pressure of oxygen in atmospheric space Ph: allowable upper limit value of hydrogen partial pressure in hydrogen gas removal target space Poi: allowable upper limit value of oxygen partial pressure in hydrogen gas removal target space
That is, the above equation (a) is obtained under the condition that the oxygen partial pressure in the atmospheric space facing the oxygen side electrode is Poo and the water vapor partial pressure in the hydrogen gas removal target space facing the hydrogen side electrode is Ps. As an equilibrium state, an applied voltage value E that keeps the hydrogen partial pressure in the hydrogen gas removal target space below the allowable upper limit Ph by the reaction shown by the above equation (c) is given.
[0018]
In addition, the above equation (b) represents the oxygen partial pressure in the hydrogen gas removal target space as an equilibrium state under the condition that the oxygen partial pressure in the atmospheric space facing the oxygen side electrode is Poo. The applied voltage value E which is kept below the allowable upper limit value Poi is given by the inhibition of the reaction indicated by.
[0019]
Therefore, as described above, if the voltage value satisfying both the expressions (A) and (B) is adopted as the applied voltage E by the DC power source, the oxygen partial pressure in the atmospheric space facing the oxygen side electrode is Poo. In addition, as an equilibrium state under the condition that the water vapor partial pressure in the hydrogen gas removal target space facing the hydrogen side electrode is Ps, both the hydrogen partial pressure and the oxygen partial pressure in the hydrogen gas removal target space are allowed. It can be kept below the upper limit values Ph and Poi, whereby the invention according to claim 2 can be implemented accurately.
[0020]
As can be seen from the equation (a), which is an equilibrium equation, when the applied voltage E is constant, if the water vapor partial pressure Ps in the hydrogen gas removal target space decreases, the hydrogen partial pressure in the hydrogen gas removal target space also decreases. Since the water vapor partial pressure Ps in the hydrogen gas removal target space changes, for example, between when the absorption chiller is operated and when the operation is stopped, the higher water vapor partial pressure in the change is set to the above. If the adopted value Ps in the determination of the applied voltage by the equation (a) is used, even if the actual water vapor partial pressure in the hydrogen gas removal target space becomes smaller than the adopted value Ps, the hydrogen partial pressure in the hydrogen gas removal target space is It is possible to reliably maintain a value smaller than the allowable upper limit Ph (that is, a value on the safe side).
[0021]
[4] In the invention according to claim 4, when the invention according to any one of claims 1 to 3 is carried out, stabilized zirconia is used for the oxygen ion conductor.
[0022]
That is, stabilized zirconia is excellent in chemical stability among various oxygen ion conductors. Therefore, if stabilized zirconia is adopted as the oxygen ion conductor, claims 1 to 3 are used. In carrying out the invention, the intended function can be obtained more reliably and stably.
[0023]
[5] In carrying out the invention according to claim 4, in the invention according to claim 5, partially stabilized zirconia is used for the oxygen ion conductor.
[0024]
In other words, among the stabilized zirconia, partially stabilized zirconia has higher oxygen ion passage resistance than fully stabilized zirconia, and is inferior in stability at 1000 ° C. or higher, but has excellent strength (particularly toughness). Because of its low cost, the removal of hydrogen gas in an absorption refrigerator generally does not require a large amount of oxygen ion conductivity because the required removal amount of hydrogen gas H ₂ is small, and it is used at 1000 ° C. or higher. Therefore, if partially stabilized zirconia is used as the oxygen ion conductor, the durability is higher than that of using fully stabilized zirconia, and the device cost is advantageous. In the implementation of the invention according to 1 to 3, the desired function can be obtained reliably and stably.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
FIG. 1 shows a double-effect absorption refrigerator using water as a refrigerant and a lithium bromide solution as an absorption liquid, and a solution pump from the bottom of the absorber 1 (common bottom with an evaporator 10 described later). 2 and the low-temperature absorbent La (diluted absorbent) returned to the high-temperature regenerator 4 through the solution heat exchanger 3 is heated by the burner 5 to generate refrigerant vapor Rs from the diluted absorbent La, The absorption liquid Lb having a medium concentration due to the generation of the refrigerant vapor Rs is introduced into the low temperature regenerator 6 after heat exchange with the diluted absorption liquid La in the high temperature side heat exchange section 3a of the solution heat exchanger 3. The refrigerant vapor Rs generated in the high-temperature regenerator 4 is exchanged with the heat transfer cylinder 7 to generate further refrigerant vapor Rs ′ from the medium concentration absorbent Lb.
[0026]
Then, the refrigerant R partially or wholly condensed by heat exchange with the medium concentration absorbent Lb through the heat transfer cylinder 7 and the refrigerant vapor Rs ′ generated in the low temperature regenerator 6 are introduced into the condenser 8. The refrigerant R is cooled by the passing cooling water W in the condenser coil 9, and the refrigerant R completely condensed by this cooling is dispersed inside the evaporator 10, and is evaporated by taking the heat of vaporization from the passing cold water C in the evaporator coil 11. By doing so, the passing cold water C of the evaporator coil 11 to be cooled is cooled.
[0027]
On the other hand, the absorption liquid Lc (concentrated absorption liquid) having a high concentration due to the generation of the refrigerant vapor Rs ′ in the low-temperature regenerator 6 exchanges heat with the dilute absorption liquid La in the low-temperature side heat exchange section 3b of the solution heat exchanger 3. After being dispersed inside the absorber 1, in this absorber 1, the evaporated refrigerant in the evaporator 10 is absorbed by the sprayed concentrated absorbent Lc under cooling by the passing cooling water W of the absorber coil 12. The inside of the evaporator 10 is maintained at a low pressure state suitable for refrigerant evaporation. Then, the absorption liquid La (diluted absorption liquid) having a low concentration again due to the absorption of the refrigerant is sent to the high-temperature regenerator 4 by the solution pump 2 so that the refrigerant R and the absorption liquid L, which are working fluids, are repeatedly circulated in the apparatus. Continue the operation of the absorption refrigerator.
[0028]
Reference numeral 13 denotes a switching valve for the hot water generation operation. In the hot water generation operation, the switching valve 13 is opened and the refrigerant vapor Rs generated in the high temperature regenerator 4 is sent to the evaporator 10 in a short-circuit manner. The hot water H passing through the evaporator coil 11 to be heated is heated by the steam Rs.
[0029]
In the absorption refrigerator, hydrogen gas H ₂ is generated due to corrosion of the metal body in the circulation system (that is, the working fluid system) of the refrigerant and the absorption liquid (particularly in the high temperature regenerator 4 which is a high temperature part). In contrast, the absorption refrigerator of the first embodiment is provided with a gas removal chamber 15 that is always in communication with the low pressure portion (evaporator 10 or absorber 1) of the working fluid system through the communication path 14, and is shown in FIG. Thus, a partially stabilized zirconia 18 (this first electrode) is an oxygen ion conductor between two porous platinum (Pt) electrodes 16, 17, one of which is a hydrogen side electrode 16 and the other is an oxygen side electrode 17. In one embodiment, a bottomed cylindrical hydrogen gas removal cell 19 sandwiching 6% yttria-stabilized zirconia (Zr _0.94 Y _0.06 O ₂₋ α)) is formed, and this cell 19 is used as a hydrogen gas removal target space. Inside the gas removal chamber 15 To face the hydrogen-side electrode 16, and, in a state for exposing the oxygen-side electrode 17 to the air space A in the external gas removal chamber 15, it is attached to the chamber wall 20 of the gas removal chamber 15.
[0030]
And while providing the electric heater 21 which heats the cell 19 and maintains it at a predetermined temperature, the conductive circuit 22 connecting the hydrogen side electrode 16 and the oxygen side electrode 17 is connected to both electrodes 16 with the hydrogen side electrode 16 as a negative electrode. 17 is provided with a constant voltage DC power source 23 for controlling ion conduction for applying a predetermined voltage E, and the applied voltage E by the DC power source 23 is a value satisfying both the following formulas (A) and (B) (this In the first embodiment, a value satisfying the following expression (A ') is set.
[0031]
E ≦ Eo + (RT / 2F) ln [Ps / (Poo ^1/2 · Ph)] …… (I)
E ≧ (RT / 4F) ln (Poo / Poi) (b)
E = Eo + (RT / 2F) ln [Ps / (Poo ^1/2 · Ph)] (b)
[0032]
here,
Eo: standard potential of reaction in which water is generated from oxygen and hydrogen R: gas constant T: absolute temperature (in the first embodiment, the cell temperature maintained by the electric heater 21)
F: Faraday constant Ps: water vapor partial pressure in the gas removal chamber 15 (in the first embodiment, a standard water vapor partial pressure in the evaporator 10 and the absorber 1 is adopted during operation of the absorption chiller)
Poo: standard oxygen partial pressure in the atmospheric space A Ph: allowable upper limit value of hydrogen partial pressure in the gas removal chamber 15 (in the first embodiment, the allowable upper limit value of hydrogen partial pressure in the evaporator 10 and the absorber 1 Adopt equal value)
Poi: an allowable upper limit value of the oxygen partial pressure in the gas removal chamber 15 (in the first embodiment, a value equal to the allowable upper limit value of the oxygen partial pressure in the evaporator 10 and the absorber 1 is adopted).
[0033]
That is, with this configuration, oxygen ions O ²⁻ moving inside the partially stabilized zirconia 18 as a solid electrolyte from the atmospheric space A through the porous oxygen-side electrode 17, and hydrogen gas H ₂ in the gas removal chamber 15 (ie, , Hydrogen gas generated in the working fluid system of the absorption chiller) is reacted at the hydrogen side electrode 16 as shown in the following formula (c),
H ₂ + O ²⁻ → H ₂ O + 2e ⁻ (c)
This effectively removes the hydrogen gas H ₂ generated in the working fluid system in the absorption chiller in the form of water molecules H ₂ O (water vapor), causing the generation of hydrogen gas in the working fluid system. The rise in the internal pressure of the absorber 1 and the evaporator 10 and the decrease in the refrigerating capacity caused thereby are prevented.
[0034]
Further, as the voltage E applied by the DC power source 23, a voltage value satisfying the above expression (A ') (a value satisfying both the above expressions (A) and (B)) is adopted. Suppressing an increase in the amount of oxygen gas generated at the hydrogen-side electrode 16 due to the following reaction (d)
^{_{2O 2- → O 2 + 4e -}} ...... ( d)
Thereby, both the hydrogen partial pressure and the oxygen partial pressure in the absorber 1 and the evaporator 10 are kept below their allowable upper limit values.
[0035]
In the figure, 24 is a screw fixture for fixing the cell 19, 25 is a packing made of gold (Au) or copper (Cu), and the cell 19 removes one or a plurality of gases depending on the amount of hydrogen gas to be removed. Equipped in chamber 15.
[0036]
The first embodiment in which the gas removal chamber 15 as the hydrogen gas removal target space equipped with the cell 19 is directly communicated with the low-pressure portion (evaporator 10 and absorber 1) of the working fluid system through the communication passage 14. In the absorption refrigerator of
For example, Ps = 0.04 × 101.325 (kPa)
Poo = 0.21 × 101.325 (kPa)
Ph = 0.001 × 101.325 (kPa)
Eo = 1.11 (V)
T = 600 (K)
If the voltage applied to both electrodes 16 and 17 is set to E = 0.993 (V) as a voltage value satisfying the above-mentioned formula (A ') under the condition
While maintaining the hydrogen partial pressure in the gas removal chamber 15 below the target 0.001 × 101.325 (kPa),
The oxygen partial pressure in the gas removal chamber 15 can be maintained at a value on the order of 10 ⁻³² (kPa) (substantially negligible value);
The inside of the absorber 1 and the evaporator 10 can be maintained at a very good low pressure state.
[0037]
[Second Embodiment]
FIG. 3 shows an example in which the apparatus configuration is partially changed in the double-effect absorption refrigerator shown in the first embodiment. The change is that the gas removal chamber 15 is changed to a low pressure part of the working fluid system. Instead of direct communication, the gas removal chamber 26 as the hydrogen gas removal target space equipped with the cell 19 as shown in FIG. 2 described above is connected to the low pressure section (evaporator 10) of the working fluid system via the gas extraction means 27. Or at the point connected to the absorber 1).
[0038]
This gas extraction means 27 uses the ejector 29 to suck in the generated hydrogen gas H ₂ in the working fluid system from the low pressure portion (evaporator 10 to absorber 1) of the working fluid system through the suction passage 30. A part La ′ of the rare absorbent La sent out from the pump 2 is guided to the ejector 29 as a reference fluid through the branch path 28, and the suction path 30 is attracted by the high-speed flow of the rare absorbent La ′ in the ejector 29. Through which gas is sucked.
[0039]
Then, the mixed fluid of the diluted absorbing liquid La ′ and the sucked hydrogen gas H ₂ functioned as the reference fluid is ejected from the tip of the internal ejection pipe 31 connected to the downstream side of the ejector 29, so that in this ejection portion The dilute absorbent La ′ and the sucked hydrogen gas H ₂ are separated into gas and liquid, and the separated hydrogen gas H ₂ is fed into the gas removal chamber 26. In the gas removal chamber 26, the above-described first implementation is performed by the equipped cell 19. Similar to the configuration, the hydrogen gas H ₂ is efficiently removed in the form of water molecules H ₂ O (water vapor) while suppressing the generation of oxygen gas O ₂ , causing the generation of hydrogen gas in the working fluid system. The rise in the internal pressure of the absorber 1 and the evaporator 10 and the decrease in the refrigerating capacity caused thereby are prevented.
[0040]
In the second embodiment, the voltage E applied to both electrodes 16 and 17 of the cell 19 by the DC power supply 23 is a value satisfying both the following formulas (a) and (b) as in the first embodiment. Is set to a value that satisfies the following equation (A ').
[0041]
E ≦ Eo + (RT / 2F) ln [Ps / (Poo ^1/2 · Ph)] …… (I)
E ≧ (RT / 4F) ln (Poo / Poi) (b)
E = Eo + (RT / 2F) ln [Ps / (Poo ^1/2 · Ph)] (b)
[0042]
here,
Eo: standard potential of reaction in which water is generated from oxygen and hydrogen R: gas constant T: absolute temperature (cell temperature maintained by electric heater 21)
F: Faraday constant Ps: water vapor partial pressure in the gas removal chamber 26 (in the second embodiment, a predetermined value is greater than the standard water vapor partial pressure in the evaporator 10 and the absorber 1 during the operation of the absorption refrigerator). Adopt large value)
Poo: standard oxygen partial pressure in the atmospheric space A Ph: allowable upper limit value of hydrogen partial pressure in the gas removal chamber 26 (in the second embodiment, from the allowable upper limit value of hydrogen partial pressure in the evaporator 10 and the absorber 1) Is also larger by a predetermined value)
Poi: Allowable upper limit value of oxygen partial pressure in gas removal chamber 26 (In the second embodiment, a value larger than the allowable upper limit value of oxygen partial pressure in evaporator 10 and absorber 1 is adopted by a predetermined value)
[0043]
In the figure, reference numeral 32 denotes a reflux path for returning the diluted absorbent La ′ separated from the hydrogen gas H _{2 by} jetting from the internal jet pipe 31 to the common bottom of the absorber 1 and the evaporator 10 by a pressure difference.
[0044]
The second embodiment in which a gas removal chamber 26 as a hydrogen gas removal target space equipped with the cell 19 is connected to the low pressure portion (evaporator 10 and absorber 1) of the working fluid system via the gas extraction means 27. In the absorption refrigerator of
In the example given in the first embodiment described above, the applied voltage is set to E = 0.955 (V), whereas if the applied voltage is set to about E = 0.8 (V), the absorber 1 and The inside of the evaporator 10 can be maintained at a good low pressure state equivalent to the example given in the first embodiment.
[0045]
In the second embodiment, as shown by a broken line in the figure, an opening / closing valve 33 is provided at the inlet of the gas removal chamber 26, and the opening / closing valve 33 is automatically opened / closed to automatically open / close the opening / closing valve 33. Alternatively, the separated hydrogen gas H ₂ may be introduced into the gas removal chamber 26 in the state, and the internal hydrogen gas H ₂ may be removed by the cell 19 with the on-off valve 33 closed.
[0046]
[Another embodiment]
Next, another embodiment is listed.
The oxygen ion conductor 18 sandwiched between the hydrogen side electrode 16 and the oxygen side electrode 17 in the cell 19 is not limited to zirconia, and various types such as cerium oxide and hafnium oxide can be adopted. The stabilizer is not limited to yttrium, and various types such as calcium, scandium, ytterbium, and magnesium can be employed.
[0047]
The porous hydrogen side electrode 16 and the porous oxygen side electrode 17 in the cell 19 are not limited to platinum, and various electrode materials can be used as long as they have sufficient corrosion resistance.
[0048]
The shape of the cell 19 is not limited to the bottomed cylindrical shape as shown in the above-described embodiment, and may be a flat or corrugated cell shape, for example.
[0049]
In the above-described embodiment, the gas removal chambers 15 and 26 are additionally provided as hydrogen gas removal target spaces facing the hydrogen side electrode 16 of the cell 19, and these gas removal chambers 15 and 26 are provided as working fluid systems in the absorption refrigerator. In some cases, a structure in which the cell 19 is directly attached to the absorber 1, the evaporator 10, or the other part of the working fluid system may be employed. The hydrogen gas removal target space that faces the side electrode 16 may be any space as long as it is an airtight space through which the generated hydrogen gas H ₂ in the working fluid system in the absorption refrigerator is conducted.
[0050]
In the second embodiment described above, an example in which the hydrogen gas H ₂ generated in the working fluid system of the absorption chiller is sent from the working fluid system to the gas removal chamber 26 using the ejector 29 has been described. In implementing the above, such an ejector is not necessarily required, and the expected function can be sufficiently obtained even in a configuration not using the ejector as shown in the first embodiment.
[0051]
In the above-described embodiment, the voltage value satisfying the above-described equation (A ') is adopted as the applied voltage E by the DC power source 23. A voltage value that satisfies both of them may be adopted, or a format in which the voltage E applied by the DC power source 23 is automatically adjusted to an appropriate value according to the situation based on various detection information may be adopted.
[0052]
The present invention is not limited to a double-effect absorption refrigerator, but can be applied to a single-effect or triple-effect absorption refrigerator, and uses a refrigerant other than water or an absorption liquid other than lithium bromide. It can also be applied to absorption refrigerators.
[Brief description of the drawings]
FIG. 1 is a block diagram of an absorption chiller showing a first embodiment. FIG. 2 is an enlarged view showing a cell structure and a cell equipment structure. FIG. 3 is a block diagram of an absorption chiller showing a second embodiment. Explanation of symbols]
15, 26 Hydrogen gas removal target space 16 Hydrogen side electrode 17 Oxygen side electrode 18 Oxygen ion conductor (activated zirconia)
19 cell 22 conductive circuit 23 DC power source A atmospheric space

Claims (5)

A cell is formed by sandwiching an oxygen ion conductor between the porous hydrogen side electrode and the porous oxygen side electrode,
This cell is placed in a state where the hydrogen side electrode faces the hydrogen gas removal target space on the working fluid system side in the absorption refrigerator and the oxygen side electrode faces the atmospheric space,
An absorption refrigerating machine in which a conductive circuit connecting the hydrogen side electrode and the oxygen side electrode is provided with a DC power source for controlling ion conduction that applies a voltage to both electrodes with the hydrogen side electrode serving as a negative electrode. Hydrogen gas removal device. 2. The absorption refrigerator hydrogen according to claim 1, wherein the voltage applied by the DC power supply is set to a value at which both of the hydrogen partial pressure and the oxygen partial pressure in the hydrogen gas removal target space are kept below their allowable upper limit values. Gas removal device. The hydrogen gas removal apparatus for an absorption refrigeration machine according to claim 2, wherein the voltage E applied by the DC power supply is set to a value satisfying both of the following formulas (a) and (b).
E ≦ Eo + (RT / 2F) ln [Ps / (Poo ^1/2 · Ph)] …… (I)
E ≧ (RT / 4F) ln (Poo / Poi) (b)
Here, Eo: standard potential of reaction in which water is generated from oxygen and hydrogen R: gas constant T: absolute temperature F: Faraday constant Ps: partial pressure of water vapor in hydrogen gas removal target Poo: partial pressure of oxygen in atmospheric space Ph: allowable upper limit value of hydrogen partial pressure in hydrogen gas removal target space Poi: allowable upper limit value of oxygen partial pressure in hydrogen gas removal target space The hydrogen gas removal apparatus for an absorption refrigerating machine according to any one of claims 1 to 3, wherein stabilized zirconia is used for the oxygen ion conductor. The hydrogen gas removal apparatus for an absorption refrigerator according to claim 4, wherein partially stabilized zirconia is used for the oxygen ion conductor.

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