JP3157303B2 - Hydrogen gas discharge circuit of absorption refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology for discharging hydrogen gas generated inside a machine such as an absorption refrigerator or an absorption heat pump (hereinafter collectively referred to as an absorption refrigerator) to the outside of the machine.

[0002]

2. Description of the Related Art As is well known, an absorption refrigerator has a regenerator, a condenser, an evaporator, an absorber and the like connected in series with a pipe to absorb a refrigerant such as water with an absorbent such as an aqueous solution of lithium bromide. This is a device for supplying and receiving heat by circulating while discharging and supplying it to cold / hot water supply / cooling / heating operation.

In the absorption refrigerator having the above structure, a regenerator, a condenser, an evaporator, an absorber, and a pipe connecting them are formed of iron or stainless steel. When an aqueous solution of lithium bromide or the like is used, the water and the absorbing liquid in the refrigerant and the absorbing liquid react with the metal of the material of the device, and hydrogen gas is generated when an oxide film or the like is formed. In particular, during the operation, the absorbent is heated to a high temperature of, for example, 160 ° C. by the regenerator, so that the above reaction is likely to occur, and the generation of hydrogen gas increases.

Further, since the evaporator and the like have a high vacuum design (for example, about several mmHg) so that the refrigerant is easily evaporated, the airtightness is enhanced by welding or the like, but the infiltration of the atmosphere is completely prevented. It is difficult to do.

[0005] Hydrogen gas generated by the above mechanism and nitrogen gas / oxygen gas which are intrusion components from the atmosphere are not condensed by cooling in a refrigerator or the like, and the solubility in the absorbing solution is extremely small, so that the evaporator is not used. And stay in the non-solution part of the absorber, and its concentration gradually increases. When the pressure of such non-condensable gas in the machine increases, the evaporation of the refrigerant is suppressed, and the refrigerating capacity is reduced. In some cases, the operation of the refrigerator may become impossible. There is.

For this reason, an uncondensable gas chamber capable of delivering the above-mentioned non-condensable gas is provided in communication with the non-solution part of the absorber, and only hydrogen gas is permeated into the non-condensable gas chamber when the temperature rises. The invention of a hydrogen gas discharge device having a structure in which a palladium cell having properties is attached is disclosed in
9864.

[0007]

The ability of the palladium cell to discharge hydrogen gas increases as the partial pressure of the hydrogen gas increases. Since the residual concentration of gas, ie, nitrogen gas / oxygen gas, gradually increases and the hydrogen gas discharge capacity decreases with time, the refrigerator may not be able to operate even with such a device installed. There was a problem, and the solution of this point was an issue.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems of the prior art. In the present invention, a low-temperature cylinder and a non-condensable gas chamber connected to the low-temperature cylinder are supplied with hydrogen through a three-way valve. A hydrogen gas discharge circuit of an absorption refrigerator connected to a gas discharge device, wherein a three-way valve normally communicates the non-condensing gas chamber and the hydrogen gas discharge device, and every predetermined time, or inside the hydrogen gas discharge device. A hydrogen gas discharge circuit, which is switched at a specific time when the pressure reaches a predetermined value and communicates the hydrogen gas discharge device with the low temperature body,

An uncondensable gas chamber having an ejector communicating with the low-temperature cylinder, and an ejector installation portion of the non-condensable gas chamber,
A hydrogen gas discharge circuit of an absorption refrigerator connected to a hydrogen gas discharge device via a three-way valve, wherein the three-way valve normally communicates the non-condensable gas chamber and the hydrogen gas discharge device, and at predetermined time intervals,
Or a hydrogen gas discharge circuit, which is switched at a specific time when the pressure in the hydrogen gas discharge device reaches a predetermined value, and communicates the hydrogen gas discharge device and an ejector installation portion of the non-condensable gas chamber, An object of the present invention is to solve the problems of the conventional technology.

[0010]

In the case of the hydrogen gas discharge circuit according to claim 1, the non-condensable gas chamber and the hydrogen gas discharge device usually communicate with each other through a three-way valve, and the hydrogen gas discharge device and the low-temperature cylinder (absorber, condenser, Evaporator, etc.), the non-condensable gas such as hydrogen gas, nitrogen gas and oxygen gas sent from the low temperature body to the non-condensable gas chamber via an ejector etc. The hydrogen gas flows into the gas discharge device, and only the hydrogen gas is selectively discharged outside the apparatus by a palladium cell or the like of the hydrogen gas discharge device, and the concentration of other non-condensable gases such as nitrogen gas and oxygen gas gradually increases.

When a predetermined time elapses or when a specific pressure of the non-condensable gas (which may be any of hydrogen gas, nitrogen gas, oxygen gas, etc.) in the hydrogen gas discharge device reaches a predetermined value,
The three-way valve is switched so that the non-condensable gas chamber and the hydrogen gas discharge device are disconnected, and the previously disconnected hydrogen gas discharge device communicates with the low temperature body, and the hydrogen gas partial pressure remaining in the hydrogen gas discharge device Since the non-condensable gas having a low ratio, that is, the non-condensable gas having a high ratio of nitrogen gas / oxygen gas flows into the low temperature body and decreases, the hydrogen gas discharging function of the hydrogen gas discharging device returns to the original state.

For this reason, when the three-way valve is switched again and the non-condensable gas chamber communicates with the hydrogen gas discharge device, the hydrogen gas in the non-condensable gas flowing into the hydrogen gas discharge device from the non-condensable gas chamber is selectively removed. It is discharged efficiently.

In the case of the hydrogen gas discharge circuit according to claim 2, the non-condensing gas chamber and the hydrogen gas discharging device usually communicate with each other through a three-way valve, and the hydrogen gas discharging device and the ejector installation portion of the non-condensing gas chamber are connected. The non-condensable gas, such as hydrogen gas, nitrogen gas, and oxygen gas, sent from the low temperature body to the non-condensable gas chamber via the ejector flows into the hydrogen gas discharge device through the three-way valve. Only the hydrogen gas is selectively discharged outside the apparatus by a palladium cell or the like of the hydrogen gas discharge device, and the concentration of other non-condensable gases such as nitrogen gas and oxygen gas gradually increases.

When the predetermined time has elapsed or when the partial pressure of the non-condensable gas in the hydrogen gas discharge device has reached a predetermined value, the three-way valve is switched to disconnect the non-condensable gas chamber from the hydrogen gas discharge device. The hydrogen gas discharge device that had been disconnected until now communicates with the ejector installation section of the non-condensable gas chamber,
Since the non-condensable gas with a low hydrogen gas partial pressure remaining in the hydrogen gas discharge device, that is, the non-condensable gas having a high ratio of nitrogen gas / oxygen gas, flows into the low-temperature cylinder and decreases, the hydrogen in the hydrogen gas discharge device is reduced. The gas discharge function returns to the original state.

Therefore, when the three-way valve is switched again and the non-condensable gas chamber communicates with the hydrogen gas discharge device, the hydrogen gas in the non-condensable gas flowing into the hydrogen gas discharge device from the non-condensable gas chamber is selectively removed. It is discharged efficiently.

[0016]

FIG. 1 shows an example of the construction of an absorption refrigerator incorporating a hydrogen discharge circuit according to claim 1. In the drawing, 11 is a high-temperature regenerator, 12 is a low-temperature regenerator, 13 is a condenser, 14 is an evaporator, 15 is an absorber, 16 is a high-temperature heat exchanger, 17 is a low-temperature heat exchanger,

In the hydrogen gas discharge circuit exemplified here, the three-way valve 21 includes the non-condensing gas chamber 22 and the absorber 15 as a low temperature body.
Can be connected to the hydrogen gas discharge device 23 as appropriate. Usually, the non-condensable gas chamber 22 and the hydrogen gas discharge device 23 communicate with each other, and the space between the hydrogen gas discharge device 23 and the absorber 15 is provided. Is uncommunicable,

When the three-way valve 21 is switched at a specific time,
The non-condensable gas chamber 22 and the hydrogen gas discharge device 23 are not connected, and the hydrogen gas discharge device 23 and the absorber 15 are connected.

The non-condensable gas chamber 22 has an ejector 22a in the upper part, and the absorbing solution pump P1 sends the absorbing solution from the absorber 15 to the high temperature regenerator 11 via the ejector 22a and the absorbing solution introducing pipe 31. Is partly branched and spouted vigorously, and by utilizing this jetting power, the gas body existing in the non-solution part A (region where the absorbing liquid does not exist as a liquid) A of the absorber 15 is used. (Refrigerant vapor, atomized absorbent,
A gas body introduction pipe 32 is provided so as to be capable of sucking a mixture of hydrogen gas, nitrogen gas, oxygen gas, and the like. Similarly, the gas body is introduced so that the gas body can be sucked also from the non-solution part B of the condenser 13. A pipe 33 is connected to the pipe.

The hydrogen gas discharge device 23 has a conventionally well-known hydrogen gas discharge tube, for example, a palladium cell 23b, in a hydrogen gas discharge tube mounting container 23a, and a built-in heater (not shown). By heating by energizing, only hydrogen gas of fine molecules can be transmitted and discharged.

The high-temperature regenerator 11, the low-temperature regenerator 12, the condenser 13, the evaporator 14, the absorber 15, the high-temperature heat exchanger 16, the low-temperature heat exchanger 17, and the piping connecting them are made of, for example, iron. As described above, if water is used as the refrigerant and an aqueous solution of lithium bromide is used as the absorbing liquid, the absorbing liquid is heated to, for example, 160 ° C. in the high-temperature regenerator 11 during operation, and the absorbing liquid that generates high-temperature steam or Hydrogen gas is generated when high-temperature refrigerant vapor (water vapor) reacts with iron constituting the device to form an oxide film on the surface.

In addition, the atmosphere may enter the machine through a connection portion of the device or a pinhole, and the hydrogen gas, the nitrogen gas, the oxygen gas, etc. accumulated in the machine in this way are:
Since it does not condense in the cooling temperature range of the refrigerator and has extremely low solubility in the absorbing solution, the absorber 15
And the concentration thereof gradually increases in the non-solution part A of the condenser 13 and the non-solution part B of the condenser 13, causing the internal pressure to rise.

However, in the absorption refrigerator having the above structure, since the hydrogen gas discharge circuit of the present invention is incorporated,
A predetermined pressure (for example, 2 kgf / cm) by the absorbent pump P1
^When a part of the absorbing liquid discharged in ² ) is discharged into the non-condensable gas chamber 22 at high speed through the absorbing liquid introducing pipe 31 and the ejector 22a, one end communicates with the non-solution part A of the absorber 15. The pressure of the ejector 22 a installation portion of the gas introduction pipe 32 is reduced, and the mixed gas such as refrigerant vapor, atomized absorption liquid, hydrogen gas, nitrogen gas, oxygen gas, etc., is present in the non-solution portion A of the absorber 15. Is drawn into the gas inlet tube 32 side, and the condenser 1
The mixed gas such as refrigerant vapor, hydrogen gas, nitrogen gas, and oxygen gas existing in the non-solution portion B of No. 3 is drawn into the gas introduction pipe 33 side, and is integrated with the absorbing liquid together with the non-condensable gas chamber 22. To be discharged.

Then, in the non-condensable gas chamber 22, only the gas that is not dissolved in the absorbing liquid rises as bubbles in the solution,
Gas and liquid are separated. That is, since hydrogen gas, nitrogen gas, oxygen gas, etc. are not substantially dissolved in the absorbing solution as described above, they rise as bubbles in the absorbing solution, and only these non-condensable gases are stored in the upper portion. . This non-condensable gas flows into the hydrogen gas discharge pipe mounting container 23a of the hydrogen gas discharge device 23 installed above via the three-way valve 21, and only hydrogen gas from outside flows out of the machine via the palladium cell 23b. Emitted selectively.

If the hydrogen gas is discharged for a long period of time, the ratio of non-condensable gas other than hydrogen gas in the hydrogen gas discharge pipe mounting container 23a, that is, nitrogen gas / oxygen gas becomes large, Since the gas partial pressure is reduced and the discharge capacity is reduced, the three-way valve 2 is provided every predetermined time, for example, every 24 hours.
1 or a pressure gauge of the non-condensable gas is installed at an appropriate part of the hydrogen gas discharging device 23, and the measured value is a predetermined value (lower limit value for hydrogen gas, lower limit value for non-condensable gas other than hydrogen gas). At the time of reaching the upper limit, for example)
Switch 1 and

Non-condensing gas chamber 22 and hydrogen gas discharging device 23
The hydrogen gas discharge device 23 and the low-temperature body absorber 15 are communicated with each other so that the ratio of nitrogen gas / oxygen gas remaining in the hydrogen gas discharge device 23 becomes high. The non-condensed gas that has flowed into the absorber 15.

For this reason, when the three-way valve 21 is switched again and the non-condensable gas chamber 22 communicates with the hydrogen gas discharge device 23, the hydrogen from the non-condensable gas flowing into the hydrogen gas discharge device 23 from the non-condensable gas chamber 22 is removed. Gas is selectively and efficiently discharged outside the machine.

FIG. 2 shows a hydrogen gas discharging circuit according to a second aspect of the present invention. In this case, the three-way valve 21 normally includes a non-condensing gas chamber 22 and a hydrogen gas discharging device 23. Communication and switching at a specific time, the hydrogen gas discharge device 23 and the ejector 22a of the non-condensable gas chamber 22
The pipe is connected so as to communicate with the installation section.

The structure of the absorption refrigerator is the same as that of the embodiment shown in FIG.

In the hydrogen gas discharge circuit in this case,
When a predetermined time elapses or when the partial pressure of hydrogen gas / nitrogen gas reaches a predetermined value, the three-way valve 21 is switched to disconnect the non-condensing gas chamber 22 and the hydrogen gas discharge device 23, and The gas discharge device 23 communicates with the ejector 22a installation portion of the non-condensable gas chamber 22,

The non-condensable gas having a high ratio of nitrogen gas / oxygen gas remaining in the hydrogen gas discharge device 23 flows into the absorber 15.

For this reason, when the three-way valve 21 is switched again and the non-condensable gas chamber 22 communicates with the hydrogen gas discharge device 23, the non-condensable gas flowing into the hydrogen gas discharge device 23 from the non-condensable gas chamber 22 is also used in this case. The hydrogen gas inside is selectively and efficiently discharged.

FIG. 3 schematically shows an experimental apparatus used for specifically verifying the effects of the present invention.
Numeral 0 is an iron vacuum container (internal volume 2516 cc) manufactured assuming the absorber 15, 101 is an electric heater, 102 is a hydrogen gas cylinder, 103 is a vacuum pump, 104 is a pressure gauge,
Reference numeral 105 denotes a recorder, V1 to V4 denote on-off valves, and 23 denotes a hydrogen gas discharge device used in the above-described embodiment.

A lithium bromide solution and 2-ethylhexanol are sealed inside the vacuum vessel 100, and the electric heater 101 heats and keeps the inside of the vessel at, for example, 40.degree. The temperature of the container 23a is set.

The on-off valve V2 is closed and the on-off valves V1, V3, V
4 is opened, the vacuum pump 103 is started, and when the internal pressure of the vacuum container 100 becomes 5 mmHg, the on-off valve V3 is closed and the on-off valve V2 is opened. The injection was performed until the pressure reached 100 mmHg, and the change in the internal pressure was recorded by the recorder 105.

That is, the hydrogen gas injected into the vacuum vessel 100 is supplied to the palladium cell 23 b of the hydrogen gas discharging device 23.
The discharge / injection operation of hydrogen gas, which is to open and close the on-off valve V2 when the internal pressure drops to 20 mmHg and replenish the internal pressure of the container from the hydrogen gas cylinder 102 to 100 mmHg when the internal pressure drops to 20 mmHg for one week repetition,

Thereafter, the on-off valve V4 is closed, the vacuum pump 103 is started with the on-off valve V3 open, and vacuum suction is performed for one minute. Thereafter, the on-off valve V3 is closed and the on-off valves V4 and V2 are connected. When the internal pressure of the vacuum container 100 is
By injecting hydrogen gas from the hydrogen gas cylinder 102 until the pressure recovers to 0 mmHg, and measuring the change in internal pressure during the injection, the change and the degree of recovery of the hydrogen gas discharge capability of the hydrogen gas discharge device 23, that is, the palladium cell 23b, are investigated. The results in Table 1 were obtained.

[0038]

[Table 1]

As can be seen from Table 1, the hydrogen gas discharging device 23, that is, the hydrogen gas discharging capability of the palladium cell 23b has a high performance of 3.4 cc / min at first, but the discharging capability decreases with time. After one week, the original function is reduced to slightly less than 40% of the original function, but the non-condensation in which the ratio of the gas remaining in the hydrogen gas discharge device 23, that is, the nitrogen gas / oxygen gas other than the hydrogen is increased. It was confirmed that the gas was completely removed to the original function by aspiration.

Since the present invention is not limited to the above embodiment, various modifications can be made without departing from the spirit of the appended claims. For example, hydrogen gas, nitrogen gas, oxygen gas, etc. Delivery of non-condensable gas such as gas
It may be performed only from the absorber 15.

[0041]

As described above, the present invention relates to a hydrogen gas for an absorption type refrigerator in which a low-temperature cylinder and an uncondensable gas chamber connected to the low-temperature cylinder are connected to a hydrogen gas discharge device via a three-way valve. In the discharge circuit, the three-way valve normally communicates the non-condensable gas chamber with the hydrogen gas discharge device, and is switched every predetermined time or at a specific time when the pressure in the hydrogen gas discharge device reaches a predetermined value, and the hydrogen gas is discharged. A hydrogen gas discharge circuit characterized by communicating the discharge device with the low temperature body,

A non-condensing gas chamber having an ejector communicating with the low-temperature cylinder, and an ejector installation portion of the non-condensing gas chamber,
A hydrogen gas discharge circuit of an absorption refrigerator connected to a hydrogen gas discharge device via a three-way valve, wherein the three-way valve normally communicates the non-condensable gas chamber and the hydrogen gas discharge device, and at predetermined time intervals,
Or it is switched at a specific time when the pressure in the hydrogen gas discharge device reaches a predetermined value, and is a hydrogen gas discharge circuit characterized by communicating the hydrogen gas discharge device and the ejector installation part of the non-condensable gas chamber,

Since the gas discharge capability of the hydrogen gas discharge device, which tends to decrease with time, can be easily and completely recovered without using an expensive vacuum pump or the like.
The evaporation of the refrigerant in the evaporator or the like is no longer suppressed, and the refrigeration capacity of the absorption refrigerator can be sufficiently exhibited over a long period of time.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing one embodiment.

FIG. 2 is an explanatory diagram showing another embodiment.

FIG. 3 is an explanatory diagram of an experimental apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 High temperature regenerator 12 Low temperature regenerator 13 Condenser 14 Evaporator 15 Absorber 16 High temperature heat exchanger 17 Low temperature heat exchanger 21 Three-way valve 22 Non-condensing gas chamber 22a Ejector 23 Hydrogen gas discharge device 23a Hydrogen gas discharge pipe mounting container 23b Palladium cell 31 Absorption liquid introduction pipe 32, 33 Gas introduction pipe 100 Vacuum container 101 Electric heater 102 Hydrogen gas cylinder 103 Vacuum pump 104 Pressure gauge 105 Recorder P1 Absorption liquid pump A / B Non-solution part V1, V2, V3, V4 Open / Close valve

Claims (2)

(57) [Claims] 1. A hydrogen gas discharge circuit of an absorption refrigerator in which a low-temperature cylinder and a non-condensable gas chamber communicating with the low-temperature cylinder are connected to a hydrogen gas discharge device through a three-way valve. ,
Normally, the non-condensing gas chamber communicates with the hydrogen gas discharge device, and switches every predetermined time or at a specific time when the pressure in the hydrogen gas discharge device reaches a predetermined value, and connects the hydrogen gas discharge device and the low temperature body. A hydrogen gas discharge circuit characterized by the following. 2. A hydrogen gas for an absorption refrigerator in which an uncondensable gas chamber having an ejector communicating with a low-temperature body and an ejector installation portion of the noncondensable gas chamber are connected to a hydrogen gas discharge device via a three-way valve. In the discharge circuit, the three-way valve normally communicates the non-condensable gas chamber with the hydrogen gas discharge device, and is switched every predetermined time or at a specific time when the pressure in the hydrogen gas discharge device reaches a predetermined value, and the hydrogen gas is discharged. A hydrogen gas discharge circuit, which communicates a discharge device with an ejector installation portion of a non-condensable gas chamber.