JPH0694338A - Safety device of ammonia absorption freezer machine - Google Patents

Abstract

PURPOSE:To prevent ammonia from being dispersed into surrounding atmosphere by a method wherein a sensing means is arranged in an absorption freezer machine in which ammonia is used as its refrigerant. CONSTITUTION:A safety device is comprised of a sealed container 10 for sealingly enclosing a cold water heat exchanger 3, a hot water heat exchanger 4, an absorption unit 5, a refrigerant vapor generating unit 6, a return flow heat exchanger 8 and an eight-way valve 9 of an ammonia absorption freezer machine other than an indoor heat exchanger 1 and an outdoor heat exchanger 2; and any of ammonia leakage detecting sensors S1, S2, S3 and S4 mounted in an ammonia refrigerant passage 21, thermal medium passages 11 and 12 heat exchanging with ammonia refrigerant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for a so-called ammonia absorption refrigerator, which uses ammonia evaporated from an aqueous solution as a refrigerant.

[0002]

2. Description of the Related Art Absorption refrigerators that use ammonia as a refrigerant have been widely used in various fields.
In recent years, it has attracted attention as an alternative refrigerant to CFCs, and it is still widely studied in various fields.

As is well known, ammonia is severely restricted from leaking to the atmosphere due to its strong toxicity and flammability, and high safety is always required when it is used.

However, as this type of safety device, for example, as shown in FIG. 4, an indoor heat exchanger 1, an outdoor heat exchanger 2, a cold water heat exchanger 3, a hot water heat exchanger 4, an absorber 5, Refrigerant vapor generator (hereinafter simply referred to as "generator") 6 / rectifier 7 /
An indoor heat exchanger 1 and an outdoor heat exchanger 2 of an ammonia absorption refrigerator configured by connecting a reflux heat exchanger 8 and a eight-way valve 9 to each other by piping.
In general, the refrigerator other than the above is simply enclosed by a closed container 10 made of a thin iron plate or the like, and no special measures have been taken against leakage of the ammonia refrigerant.

However, in order to prevent leakage from the piping section and the heat exchanger, a leaky inspection was strictly carried out, and the refrigeration system was installed in a separate building.

Symbols P1, P2, and P3 are circulation pumps, V1 and V2 are pressure reducing valves, and 61 is heating means for supplying heat to the generator 6.

[0007]

That is, since none of the conventional safety measures can completely prevent the leakage of the ammonia refrigerant into the atmosphere, the problem to be solved has been a problem.

[0008]

The present invention has been made to solve the above-mentioned problems of the prior art, and excludes an indoor heat exchanger and an outdoor heat exchanger of an absorption refrigerator using ammonia as a refrigerant. , A cold water heat exchanger, a hot water heat exchanger, an absorber, a refrigerant vapor generator, a switching valve, a closed container that hermetically surrounds a rectifier, and at least one of an ammonia refrigerant path and a heat medium path for exchanging heat with the ammonia refrigerant. A safety device for an ammonia absorption refrigerator, which comprises an ammonia leakage detection means installed in

In an absorption refrigerator using ammonia as a refrigerant, excluding the indoor heat exchanger and the outdoor heat exchanger, a cold water heat exchanger, a hot water heat exchanger, an absorber, a refrigerant vapor generator, a switching valve,
A sealed container that hermetically surrounds a rectifier, etc., an ammonia refrigerant flows inside, a heat medium flows outside, and a gas having a lower activity than ammonia between the ammonia refrigerant flow and the heat medium flow, and the pressure of the ammonia refrigerant. A safety device for an ammonia absorption refrigerating machine, characterized by comprising a triple pipe that is sealed at a higher pressure to form a cold water heat exchanger and a hot water heat exchanger.

A safety device for an ammonia absorption refrigerating machine as described above, further comprising means for measuring a pressure of a gas having a lower activity than ammonia, which is enclosed in the triple pipe, to detect leakage of the ammonia refrigerant. And solve the problems of the prior art.

[0011]

[Effect] Even if the refrigerant path including the absorber and the generator is corroded or cracked, and ammonia in the refrigerant leaks from the refrigerator, these devices are hermetically enclosed by the hermetically sealed container. The refrigerant never leaks into the atmosphere, and the ammonia leakage detecting means quickly detects the ammonia leakage.

Further, in the safety device according to the second aspect of the present invention, the triple pipes constituting the cold water heat exchanger and the hot water heat exchanger,
Even if corrosion or cracks occur on the pipe wall where the ammonia refrigerant flows,
Gases with a lower activity than ammonia (for example, helium, argon, nitrogen, carbon dioxide, etc.) enclosed in the intermediate layer with a pressure higher than that of the ammonia refrigerant flow into the inner pipeline, and the ammonia refrigerant enters the intermediate pipeline. Prevent it from leaking.

Therefore, the ammonia refrigerant does not mix with the heat medium that carries the heat to the indoor heat exchanger and the outdoor heat exchanger by flowing through the outermost pipe of the triple pipe, so that the ammonia refrigerant leaks into the atmosphere. I have no concerns.

Further, in the safety device according to the third aspect of the present invention, the ammonia refrigerant leakage detection means for measuring pressure, which is installed in the intermediate pipe of the triple pipe, detects the decrease in pressure and knows the leakage of the refrigerant. Therefore, repairs and other measures can be taken promptly.

[0015]

Embodiments of the present invention will be described below with reference to FIGS. Regarding the reference numerals, the same reference numerals are given to the portions having the same functions as those of the device shown in FIG.

As in the case of FIG. 4, the closed container 10 has a cold water heat exchanger 3, a hot water heat exchanger 4, an absorber 5 and a generator except for the indoor heat exchanger 1 and the outdoor heat exchanger 2 of the ammonia absorption refrigerator. The vessel 6, the rectifier 7, the reflux heat exchanger 8 and the eight-way valve 9 are housed in a sealed state.

The ammonia leakage detection sensor (hereinafter referred to simply as "sensor") S1 is used for the cold water heat exchanger 3, the sensor S2 is used for the hot water heat exchanger 4, and the sensor S3 is used for the absorber 5.
The sensor S4 is installed in the heat medium path 11 passing through the generator 6, the sensor S4 is installed in the heat medium path 12 passing through the generator 6, and the sensor S5 is installed inside the closed container 10.

When the ammonia refrigerant heated and vaporized by the generator 6 is installed on the side of the refrigerant path 21 leading to the absorber 5, the sensors S1 and S2 generate corrosion or cracks in the refrigerant pipe, and the ammonia refrigerant is cooled. Is leaked and the pressure in the pipe decreases, so if a pressure sensor of the type that can detect this is installed at least at one location of the refrigerant pipe including the cold water heat exchanger 3 and the hot water heat exchanger 4, the Leakage can be detected reliably.

Further, cold water heat exchanger 3 and hot water heat exchanger 4
However, for example, when the double pipe is formed as shown in FIG. 2 and the ammonia refrigerant flows through the inner pipe line 31 and the heat medium (for example, water) flows through the outer pipe line 32, If the ammonia refrigerant leaks to the heat medium side of the pipe 32 due to corrosion of the pipe wall 34 or the like, the PH value of the heat medium changes. Therefore, the sensors S1 and S2 flow through the pipe 32 through which the heat medium flows (preferably on the outlet side). It can also be installed as a PH meter. Further, a sensor that can directly detect the presence of ammonia may be used.

In this case, if the sensor is installed in only one of the cold water heat exchanger 3 and the hot water heat exchanger 4,
Since it may not be possible to detect this depending on the position where the ammonia refrigerant leaks, when installing the sensor in the pipe 32 through which the heat medium flows, it is installed in both the cold water heat exchanger 3 and the hot water heat exchanger 4. .

Further, as shown in FIG. 3, the cold water heat exchanger 3 and the hot water heat exchanger 4 are formed in a triple pipe, and the ammonia refrigerant is caused to flow in the innermost pipe line 31 and the heat medium in the outermost pipe line 32. (For example, water) is flown, and a gas having a lower activity than ammonia as a refrigerant and having excellent thermal conductivity (for example, helium gas) is sealed in the intermediate pipe line 33 at a pressure higher than the pressure of the ammonia refrigerant, If the pressure in the conduit 33 is detected by a sensor,

Even if the pipe wall 34 is corroded or cracked, it is possible to prevent a stable gas from flowing into the pipe line 33 having a low pressure from the pipe line 33 having a high pressure and flowing out the ammonia refrigerant into the pipe line 33.
Moreover, from the pressure change (abnormal decrease) of the pipe line 33, the pipe wall 34
You can know the damage of.

In this case as well, for the same reason as in the case of FIG. 2, pressure type ammonia leakage detection sensors are installed in both the cold water heat exchanger 3 and the hot water heat exchanger 4.

The sensor S3 installed in the heat medium path 11 passing through the absorber 5 is a type of sensor that directly detects the PH value of the heat medium (for example, water) and the presence of ammonia. When corrosion or cracks are generated in the portion of the container 8 and ammonia refrigerant is mixed, this can be detected.

The sensor S4 is also the same type of sensor as the sensor S3, and the heat medium path 12 passing through the inside of the generator 6 is used.
Further, when corrosion or cracks occur and the ammonia refrigerant of the generator 6 mixes into the heat medium, this can be detected.

The sensor S5 installed at a desired position in the closed container 10 (a high position is preferable because it detects ammonia of low density) is also the same type of sensor as the sensors S3 and S4, and the presence of leaked ammonia is It can be easily detected.

Therefore, even if the ammonia refrigerant leaks due to corrosion or cracks in the absorber 5, the generator 6, the refrigerant path 21, etc., it will be harmed to the human body etc. because it is hermetically enclosed by the closed container 10. Never, and there is no danger of fire.

Further, the heat medium passages 11 and 12 may be corroded or cracked, and the ammonia refrigerant may be mixed from the cold water heat exchanger 3, the hot water heat exchanger 4, the absorber 5 and the generator 6. Also, since the sensor for detecting the ammonia refrigerant is provided in the heat medium passage, it is possible to quickly detect the leakage of the ammonia refrigerant from the refrigerant system.

Further, in the case of the safety device in which the cold water heat exchanger 3 and the hot water heat exchanger 4 are formed in a triple pipe as shown in FIG. 3, even if the pipe wall 34 is corroded or cracked, the ammonia refrigerant will not pass through the pipe. Since it does not leak to the roads 33 and 32, the safety is extremely high.

Since the present invention is not limited to the above-mentioned embodiments, various modifications can be made without departing from the spirit of the claims.

For example, when the sensors S1 and S2 are installed in the heat medium paths respectively passing through the cold water heat exchanger 4 and the hot water heat exchanger 5, they can be installed at positions other than the heat exchanger.

The cold water heat exchanger 3 formed in the triple pipe
The gas sealed in the conduit 33 of the hot water heat exchanger 4 may be argon, nitrogen, carbon dioxide, etc., in addition to the helium.

The heat medium that exchanges heat with the ammonia refrigerant and passes through the indoor heat exchanger 1, the outdoor heat exchanger 2 and the like may be chemically stable and highly safe. Also, antifreeze such as polyethylene glycol aqueous solution or silicone oil can be used.

[0034]

INDUSTRIAL APPLICABILITY As described above, the present invention is an absorption refrigerator using ammonia as a refrigerant, excluding an indoor heat exchanger and an outdoor heat exchanger, a cold water heat exchanger, a hot water heat exchanger, an absorber, A refrigerant vapor generator, a switching valve, a rectifier, etc. are hermetically enclosed to form a closed container, and an ammonia leakage detecting means installed in at least one of an ammonia refrigerant path and a heat medium path for exchanging heat with the ammonia refrigerant. Is a safety device for the ammonia absorption refrigerator,

A cold water heat exchanger, a hot water heat exchanger, an absorber, a refrigerant vapor generator, a switching valve of an absorption refrigerator using ammonia as a refrigerant, excluding the indoor heat exchanger and the outdoor heat exchanger,
A sealed container that hermetically surrounds a rectifier, etc., an ammonia refrigerant flows inside, a heat medium flows outside, and a gas having a lower activity than ammonia between the ammonia refrigerant flow and the heat medium flow, and the pressure of the ammonia refrigerant. A safety device for an ammonia absorption refrigerator, which is configured by a triple pipe that forms a cold water heat exchanger and a hot water heat exchanger by enclosing at a higher pressure,

A safety device for an ammonia absorption refrigerator as described above, further comprising means for measuring a pressure of a gas sealed in a triple pipe, the activity of which is lower than that of ammonia, and detecting leakage of an ammonia refrigerant. Because there is

Even if the ammonia refrigerant leaks due to corrosion or cracks in the absorber / generator / refrigerant path, etc., the ammonia refrigerant does not leak into the atmosphere because it is airtightly enclosed by the sealed container. Does not harm
There is no danger of fire.

Even if the heat medium passage for exchanging heat with the ammonia refrigerant is corroded or cracked, the ammonia refrigerant may be mixed into the heat medium passage from the cold water heat exchanger, the hot water heat exchanger, the generator or the like. The leakage detection sensor installed in the heat medium path can promptly detect the leakage of the ammonia refrigerant from the refrigerant system.

In particular, the cold water heat exchanger / hot water heat exchanger is shown in FIG.
In the case of the safety device formed in the triple pipe illustrated in Figure 2, even if the pipe wall is corroded or cracked, ammonia refrigerant will leak into the path of the heat medium to the indoor heat exchanger, the outdoor heat exchanger, etc. It is extremely safe and has a remarkable effect.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of the present invention.

FIG. 2 is an explanatory diagram of a main part of the present invention.

FIG. 3 is an explanatory diagram of a main part of the present invention.

FIG. 4 is an explanatory diagram of a conventional example.

[Explanation of symbols]

1 Indoor heat exchanger 2 Outdoor heat exchanger 3 Cold water heat exchanger 4 Hot water heat exchanger 5 Absorber 6 (Refrigerant vapor) generator 7 Fractionator 8 Reflux heat exchanger 9 Eight-way valve 10 Closed container 11/12 Heat medium Route 21 Refrigerant route 31, 32, 33 Pipe 34 Pipe wall P1, P2, P3 Pump S1, S2, S3, S4, S5 (Ammonia leak detection) sensor V1, V2 Pressure reducing valve

Claims (3)

[Claims] 1. A cold water heat exchanger, a hot water heat exchanger, an absorber, a refrigerant vapor generator, a switching valve, and a refiner of an absorption refrigerator using ammonia as a refrigerant, excluding an indoor heat exchanger and an outdoor heat exchanger. A safety device for an ammonia absorption refrigerator, comprising a hermetically sealed container that hermetically encloses a condenser and the like, and ammonia leakage detection means installed in at least one of an ammonia refrigerant path and a heat medium path for exchanging heat with the ammonia refrigerant. . 2. A cold water heat exchanger, a hot water heat exchanger, an absorber, a refrigerant vapor generator, a switching valve, and a refiner of an absorption refrigerator that uses ammonia as a refrigerant, excluding an indoor heat exchanger and an outdoor heat exchanger. A closed container that hermetically surrounds a condenser, etc., an ammonia refrigerant flows inside, a heat medium flows outside, and a gas with a lower activity than ammonia between the ammonia refrigerant stream and the heat medium stream A safety device for an ammonia absorption refrigerating machine, comprising: a triple pipe that is sealed with a large pressure to form a cold water heat exchanger and a hot water heat exchanger. 3. The ammonia absorption refrigerating machine according to claim 2, further comprising means for measuring leakage of ammonia refrigerant by measuring the pressure of gas enclosed in a triple pipe, the activity of which is lower than that of ammonia. Safety device.