JPH0674614A - Hydrogen gas discharge circuit of absorption refrigerating machine - Google Patents

Abstract

PURPOSE:To enable a refrigerating capacity of an absorption refrigerating machine to be realized for a long period of time by a method wherein a three-way valve communicates between a non-condensed gas chamber and a hydrogen gas discharging device, the three-way valve is changed over for every predetermined time or when a physical amount such as pressure and the like reaches a predetermined value and then the hydrogen gas discharging device communicates with a low temperature drum. CONSTITUTION:A hydrogen gas discharging circuit is operated such that a three-way valve 21 can connect properly a non-condensed gas chamber 22 and an absorber 15 of low temperature drum with a hydrogen gas discharging device 23. Normally, the non-condensed gas chamber 22 and the hydrogen gas discharging device 23 communicate with each other and the hydrogen gas discharging device 23 and the absorber 15 do not communicate with each other. At the specified time, the three-way valve 21 is changed over to cause the non-condensed gas chamber 22 not to communicate with the hydrogen gas discharging device 23, resulting in that the hydrogen gas discharging device 23 communicates with the absorber 15. The hydrogen gas discharging device 23 has a palladium cell 23b at a hydrogen gas discharging pipe fixing container 23a, a heater stored in it is electrically energized to perform heating of it and only the fine molecular hydrogen gas is discharged through the cell.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for discharging hydrogen gas generated inside a machine such as an absorption refrigerating machine or an absorption heat pump (hereinafter referred to as absorption refrigerating machine) 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, etc. connected in series by pipes to absorb a refrigerant such as water with an absorption liquid such as an aqueous solution of lithium bromide. It is a device for supplying and receiving heat by circulating it while releasing it, and supplying it to cold / hot water and heating / cooling operation.

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

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

The hydrogen gas generated by the above mechanism and the nitrogen gas / oxygen gas, which are invasion components from the atmosphere, do not condense upon cooling in a refrigerator and the solubility in the absorbing liquid is extremely small, so that the evaporator is used. And stays in the non-solution part of the absorber, and its concentration gradually increases. When the pressure of such a non-condensable gas in the machine increases, the evaporation of the refrigerant is suppressed and the refrigerating capacity decreases, and in some cases, the operation of the refrigerator itself may become impossible. There is.

For this reason, a non-condensable gas chamber capable of delivering the non-condensable gas from the non-solution portion of the absorber is provided in communication with the non-condensable gas chamber, and only hydrogen gas permeates when the temperature rises. An invention of a hydrogen gas discharge device having a structure having a palladium cell attached thereto is disclosed in Japanese Patent Laid-Open No. 59-13
It is proposed in Japanese Patent No. 9864.

[0007]

The capacity of the palladium cell for discharging hydrogen gas increases as the partial pressure of hydrogen gas increases. However, in the hydrogen gas discharging device of the above-described configuration, non-condensing other than hydrogen gas Since the residual concentration of gas, that is, nitrogen gas, oxygen gas, etc., gradually increases and the hydrogen gas discharge capacity decreases with the passage of time, it can be said that even if such a device is installed, the operation of the refrigerator may become impossible. However, there was a problem to solve this problem.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, in which a low temperature cylinder and a non-condensable gas chamber communicating with the low temperature cylinder are connected to each other via a three-way valve. A hydrogen gas discharge circuit of an absorption chiller connected to a gas discharge device, in which a three-way valve normally connects the non-condensable gas chamber and the hydrogen gas discharge device, and a physical quantity such as pressure is set at predetermined intervals. It switches at a specific time when it reaches a value, and a hydrogen gas discharge circuit characterized by connecting the hydrogen gas discharge device and the low temperature cylinder to each other,

A non-condensable gas chamber having an ejector communicating with the cold cylinder, and an ejector installation portion of the non-condensable gas chamber,
A hydrogen gas discharge circuit of an absorption chiller connected to a hydrogen gas discharge device via a three-way valve, the three-way valve is usually in communication with the non-condensable gas chamber and the hydrogen gas discharge device, every predetermined time,
Or a physical quantity such as pressure is switched at a specific time when it reaches a predetermined value, and a hydrogen gas discharge circuit characterized by connecting the hydrogen gas discharge device and an ejector installation part of the non-condensing gas chamber is provided. To solve the problem of.

[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 normally communicate with each other through a three-way valve, and the hydrogen gas discharge device and the low temperature cylinder (absorber, condenser, condenser, Since non-condensable gases such as hydrogen gas, nitrogen gas and oxygen gas sent from the low temperature cylinder to the non-condensable gas chamber through the ejector etc. The hydrogen gas flows into the gas discharge device, and only the hydrogen gas is selectively discharged to the outside by a palladium cell 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 the physical quantity such as the partial pressure of the non-condensable gas (hydrogen gas, nitrogen gas, oxygen gas, etc.) in the hydrogen gas discharge device reaches a predetermined value, the three-way valve And the non-condensable gas chamber and the hydrogen gas discharge device are cut off, and the hydrogen gas discharge device that was previously cut off communicates with the low temperature cylinder, and the hydrogen gas partial pressure remaining in the hydrogen gas discharge device is low. Since the non-condensable gas, in other words, the non-condensable gas having a high ratio of nitrogen gas / oxygen gas, etc. flows into the low temperature cylinder and decreases, the hydrogen gas discharging function of the hydrogen gas discharging device returns to the original state.

Therefore, when the three-way valve is switched again and the noncondensable gas chamber and the hydrogen gas discharge device communicate with each other, the hydrogen gas in the noncondensable gas flowing from the noncondensable gas chamber into the hydrogen gas discharge device is selectively discharged. Efficiently discharged.

In the case of the hydrogen gas discharge circuit according to claim 2, normally, the non-condensable gas chamber and the hydrogen gas discharge device communicate with each other through a three-way valve, and the hydrogen gas discharge device and the ejector installation portion of the non-condensable gas chamber are connected. The non-condensable gas such as hydrogen gas, nitrogen gas, oxygen gas, etc. sent from the low temperature cylinder to the non-condensable gas chamber through the ejector flows into the hydrogen gas discharge device through the three-way valve. Only hydrogen gas is selectively discharged to the outside by a palladium cell or the like of a 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 the physical quantity such as the partial pressure of the non-condensable gas in the hydrogen gas discharge device reaches a predetermined value, the three-way valve is switched to separate the non-condensable gas chamber and the hydrogen gas discharge device. The non-condensable gas with a low partial pressure of hydrogen gas remaining in the hydrogen gas discharge device, that is, nitrogen gas Since the non-condensable gas having a high ratio such as oxygen gas flows into the cold cylinder and decreases, the hydrogen gas discharging function of the hydrogen gas discharging device returns to the original state.

Therefore, when the three-way valve is switched again and the non-condensable gas chamber and the hydrogen gas discharging device communicate with each other, the hydrogen gas in the non-condensing gas flowing into the hydrogen gas discharging device from the non-condensing gas chamber is selectively Efficiently discharged.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a constitutional example of an absorption refrigerator incorporating a hydrogen discharge circuit according to claim 1, in which 11 is a high temperature regenerator, 12 is a low temperature regenerator, and 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 illustrated here, the three-way valve 21 is the non-condensable gas chamber 22 and the absorber 15 which is a cold cylinder.
And the hydrogen gas exhaust device 23 can be appropriately connected to each other. Normally, the non-condensable gas chamber 22 and the hydrogen gas exhaust device 23 communicate with each other, and the hydrogen gas exhaust device 23 and the absorber 15 are connected to each other. Out of order,

When the three-way valve 21 is switched at a specific time,
The non-condensable gas chamber 22 and the hydrogen gas exhaust device 23 are in communication with each other, and the hydrogen gas exhaust device 23 and the absorber 15 are in communication with each other.

The non-condensable gas chamber 22 has an ejector 22a at the upper part, and the absorbent pump P1 sends the absorbent from the absorber 15 to the high temperature regenerator 11 via the ejector 22a and the absorbent introducing pipe 31. Part of the gas is branched and ejected vigorously, and by utilizing this ejection force, the gas body existing in the non-solution part (the region where the absorbing liquid does not exist as a liquid) A of the absorber 15 is present. (Refrigerant vapor / mist absorption liquid /
A gas body introduction pipe 32 is provided so that a mixture of hydrogen gas, nitrogen gas, oxygen gas, etc.) can be sucked, and similarly, a gas body is introduced so that the gas body can be sucked from the non-solution portion B of the condenser 13 as well. The pipe 33 is connected to the pipe.

The hydrogen gas discharge device 23 has a hydrogen gas discharge pipe mounting container 23a and a hydrogen gas discharge pipe known in the prior art, for example, a palladium cell 23b, in a heater (not shown) incorporated therein. By energizing and heating, only hydrogen gas of fine molecules can be permeated 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 pipes connecting them are formed of, for example, iron. As described above, when water is used as the refrigerant and a lithium bromide aqueous solution 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 is generated. Hydrogen gas is generated when a high-temperature refrigerant vapor (water vapor) or the like reacts with iron constituting the device to form an oxide film on the surface.

Further, the atmosphere may enter the inside of the machine through the connecting parts of the equipment, pinholes, etc., but the hydrogen gas, nitrogen gas, oxygen gas, etc. thus accumulated in the machine,
In the cooling temperature range of the refrigerator, the absorber 15 does not condense and the solubility in the absorbing liquid is extremely small.
Staying in the non-solution portion A and the non-solution portion B of the condenser 13 and the concentration thereof gradually increases, which causes a rise in the internal pressure.

However, since the hydrogen gas discharge circuit of the present invention is incorporated in the absorption refrigerator having the above structure,
Predetermined pressure (for example, 2 Kgf / cm by the absorption liquid pump P1)
^When a part of the absorbent discharged in ² ) is discharged into the non-condensing gas chamber 22 at high speed through the absorbent 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 22a installed portion of the gas body introduction pipe 32 is lowered, and a mixed gas of refrigerant vapor, atomized absorbing liquid, hydrogen gas, nitrogen gas, oxygen gas, etc. existing in the non-solution portion A of the absorber 15 Is drawn into the gas body introduction pipe 32 side, and the condenser 1
The mixed gas of the refrigerant vapor, hydrogen gas, nitrogen gas, oxygen gas and the like existing in the non-solution portion B of No. 3 is drawn into the gas body introducing pipe 33 side, and together with the absorbing liquid, the non-condensing gas chamber 22 To discharge.

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-liquid is separated. That is, since hydrogen gas, nitrogen gas, oxygen gas, etc. are not substantially dissolved in the absorbing liquid as described above, they rise as bubbles in the absorbing liquid and only these non-condensing gases are stored in the upper part. . This non-condensed 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 the hydrogen gas is discharged from the inside to the outside via the palladium cell 23b. It is selectively discharged.

If the hydrogen gas is discharged for a long period of time, the proportion of non-condensable gas other than hydrogen gas, that is, nitrogen gas / oxygen gas, in the hydrogen gas discharge pipe mounting container 23a becomes large, and Since the gas partial pressure is reduced and the discharge capacity is reduced, the three-way valve 2 is operated every predetermined time, for example, every 24 hours.
1 or install a pressure gauge for the non-condensable gas at an appropriate portion of the hydrogen gas discharge device 23, and the measured value by this is a predetermined value (for hydrogen gas, the lower limit value, if the gas is a non-condensable gas other than hydrogen gas, The three-way valve 2
Switch 1

Non-condensable gas chamber 22 and hydrogen gas discharge device 23
Are made non-conductive, and the hydrogen gas discharge device 23, which has been cut off until now, and the absorber 15, which is a low temperature cylinder, are made to communicate with each other, and the ratio of nitrogen gas, oxygen gas, etc. remaining in the hydrogen gas discharge device 23 becomes high. The non-condensed gas is flowed into the absorber 15.

Therefore, when the three-way valve 21 is switched again and the non-condensable gas chamber 22 and the hydrogen gas exhaust device 23 communicate with each other, hydrogen is extracted from the non-condensable gas flowing from the non-condensable gas chamber 22 into the hydrogen gas exhaust device 23. Gas is selectively and efficiently discharged out of the machine.

FIG. 2 shows a hydrogen gas discharge circuit according to a second aspect of the present invention. In the hydrogen gas discharge circuit in this case, a three-way valve 21 normally has a non-condensable gas chamber 22 and a hydrogen gas discharge device 23. The hydrogen gas exhaust device 23 and the ejector 22a of the non-condensable gas chamber 22 communicate with each other and switch at a specific time.
It is connected by piping so that it communicates with the installation part.

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

Also in the hydrogen gas discharge circuit in this case,
At a specific time such as when a predetermined time elapses or when the partial pressure of hydrogen gas, nitrogen gas, etc. reaches a predetermined value, the three-way valve 21 is switched and the non-condensable gas chamber 22 and the hydrogen gas discharge device 23 are switched.
And the hydrogen gas discharge device 23 and the non-condensable gas chamber 2
To communicate with the 2 ejector 22a installation section,

The non-condensable gas having a high ratio of nitrogen gas, oxygen gas, etc. remaining in the hydrogen gas discharge device 23 is made to flow into the absorber 15.

Therefore, when the three-way valve 21 is switched again and the non-condensable gas chamber 22 and the hydrogen gas exhaust device 23 communicate with each other, the non-condensable gas flowing from the non-condensable gas chamber 22 into the hydrogen gas exhaust device 23 is also removed. Hydrogen gas inside is selectively and efficiently discharged.

FIG. 3 shows an outline of an experimental apparatus that was carried out to specifically verify the effects of the present invention.
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 is a recorder, V1 to V4 are on-off valves, and 23 is the hydrogen gas discharge device used in the above-mentioned embodiment.

Lithium bromide solution and 2-ethylhexanol are enclosed in the vacuum container 100, and the electric heater 101 heats and keeps the inside of the container at, for example, 40 ° C., so that the hydrogen gas exhaust pipe is actually attached. The temperature of the container 23a is reached.

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 reaches 5 mmHg, the opening / closing valve V3 is closed and the opening / closing valve V2 is opened. Injection was performed until the pressure reached 100 mmHg, and the change in internal pressure was recorded by the recorder 105.

That is, the hydrogen gas injected into the vacuum vessel 100 is the palladium cell 23b of the hydrogen gas discharge device 23.
Is discharged to the outside of the machine, and when the internal pressure drops to 20 mmHg, the on-off valve V2 is opened, and hydrogen gas is discharged and injected from the hydrogen gas cylinder 102 until the internal pressure of the container recovers 100 mmHg for one week. repetition,

Thereafter, the on-off valve V4 is closed, the on-off valve V3 is opened, the vacuum pump 103 is activated to perform vacuum suction for one minute, and then the on-off valve V3 is closed to open the on-off valves V4 and V2. Open, the internal pressure of the vacuum container 100 is 10
Hydrogen gas is injected from the hydrogen gas cylinder 102 until 0 mmHg is recovered, and the change in internal pressure during this time is measured to investigate the transition and the degree of recovery of the hydrogen gas discharge capacity by the hydrogen gas discharge device 23, that is, the palladium cell 23b. The results shown in Table 1 were obtained.

[0038]

[Table 1]

From Table 1, the hydrogen gas discharging device 23, that is, the hydrogen gas discharging capacity of the palladium cell 23b has a high performance of 3.4 cc / min at the beginning, but the discharging capacity decreases with the passage of time. However, after one week, the function is reduced to just 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 hydrogen has increased. It was confirmed that the original function could be completely restored by sucking out the gas.

Since the present invention is not limited to the above embodiment, various modifications can be made without departing from the scope of the claims. For example, the three-way valve 21 can be switched. In addition to time and pressure, it is also possible to measure and control physical quantities such as temperature in the generator. In addition, non-condensable gas such as hydrogen gas, nitrogen gas, oxygen gas can be delivered only from the absorber 15. It may be done.

[0041]

As described above, according to the present invention, the low temperature cylinder and the non-condensing gas chamber communicating with the low temperature cylinder are connected to the hydrogen gas discharge device through the three-way valve. In the discharge circuit, the three-way valve normally connects the non-condensable gas chamber and the hydrogen gas discharge device, and switches at a predetermined time or at a specific time when a physical quantity such as pressure reaches a predetermined value, and the hydrogen gas discharge device is connected. It is a hydrogen gas discharge circuit characterized by communicating with the low temperature cylinder,

A non-condensable 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 chiller connected to a hydrogen gas discharge device via a three-way valve, the three-way valve is usually in communication with the non-condensable gas chamber and the hydrogen gas discharge device, every predetermined time,
Or, when the physical quantity such as pressure is switched at a specific time when it reaches a predetermined value, the hydrogen gas discharge circuit is characterized by connecting the hydrogen gas discharge device and the ejector installation part of the non-condensing gas chamber.

The gas discharge capacity of the hydrogen gas discharge device, which tends to decrease with the passage of time, can be easily and completely restored without using an expensive vacuum pump or the like.
The evaporation of the refrigerant in the evaporator is not suppressed, and the refrigerating capacity of the absorption chiller can be fully exerted for a long period of time.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example.

FIG. 2 is an explanatory diagram showing another embodiment.

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

[Explanation 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 body 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)

[Claims] 1. A hydrogen gas discharge circuit of an absorption chiller 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 via a three-way valve, the three-way valve comprising: ,
Normally, the non-condensable gas chamber and the hydrogen gas discharge device are communicated with each other, and the hydrogen gas discharge device and the low temperature cylinder are communicated with each other at a predetermined time or at a specific time when a physical quantity such as pressure reaches a predetermined value. A hydrogen gas exhaust circuit. 2. A hydrogen gas of an absorption chiller in which a non-condensable gas chamber having an ejector communicating with a low temperature cylinder and an ejector installation portion of the non-condensable gas chamber are connected to a hydrogen gas discharge device via a three-way valve. In the discharge circuit, the three-way valve normally connects the non-condensable gas chamber and the hydrogen gas discharge device, and switches at a predetermined time or at a specific time when a physical quantity such as pressure reaches a predetermined value, and the hydrogen gas discharge device is connected. A hydrogen gas discharge circuit that communicates with the ejector installation part of the non-condensing gas chamber.