JPH0694336A - Safety device of ammonia absorption freezer machine - Google Patents

Abstract

PURPOSE:To prevent ammonia from being dispersed into surrounding air through an absorption freezer in which ammonia is used as refrigerant. CONSTITUTION:A cold water heat exchanger 3, a hot water heat exchanger 4, an absorption unit 5, a refrigerant vapor generating unit 6 and an eight-way valve 7 other than an indoor heat exchanger 1 and an outdoor heat exchanger 2 are enclosed by a sealed container 8. This sealed container 8 is provided with a safety means 2 comprising a safety valve 91 broken and opened at a pressure more than a predetermined pressure (for example, 0.3 kg.f/cm<2>), a discharging passage 92 arranged at a downstream side, an ammonia adsorption agent (for example, actived carbon) arranged in the discharging passage and a plurality of heat radiation fins 94 installed at an outer periphery of the discharging passage. Since it is mounted in such a manner that it may communicate through the safety valve 91, if the piping part is cracked to cause ammonia of refrigerant to be leaked and the inner pressure of the closed container 3 is increased, the safety valve 91 is opened, gas of high pressure flows into the discharging passage 92 and ammonia is adsorbed by the adsorption agent 93 and removed.

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, Refrigerator vapor generator (hereinafter, simply referred to as generator) 6 and eight-way valve 7 are connected in piping to form an ammonia absorption refrigerator, and the refrigerator except indoor heat exchanger 1 and outdoor heat exchanger 2 is simply a thin iron plate. It is common to enclose it in a closed container 8 made of, for example, and no special measures have been taken against leakage of ammonia.

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, V3 and V4 are safety valves, and T1.
・ T2 ・ T3 ・ T4 ・ T5 are temperature sensors, SW1 ・ SW
2 is a pressure switch.

[0007]

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

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and includes a safety valve that opens at a predetermined pressure or more, an exhaust passage provided on the downstream side of the safety valve, Safety of the ammonia absorption refrigerator, characterized in that a safety means composed of an ammonia treating agent installed in the exhaust passage is installed in a closed container surrounding the refrigerator of the ammonia absorption refrigerator so as to be able to communicate through the safety valve. Device,

A safety valve that opens at a predetermined pressure or more, an exhaust passage provided downstream of the safety valve, an ammonia decomposing agent installed in the exhaust passage, and an oxidizing agent or a blowing means installed downstream of the ammonia decomposing agent. A safety measure consisting of and in a closed container surrounding the refrigerator of the ammonia absorption refrigerator,
A safety device for an ammonia absorption refrigerator, which is installed so as to be able to communicate with each other via the safety valve, and solves the problems of the conventional art.

[0010]

[Function] When ammonia in the refrigerant leaks from the refrigerator surrounded by the closed container for some reason and the pressure rises, the safety valve of the safety means installed in the closed container opens, and the high pressure gas containing ammonia is exhausted by the safety means. Ammonia in the air flows out to the passage, and the ammonia treatment agent installed in the exhaust passage

If the treatment agent is an adsorbent such as activated carbon, it is adsorbed and removed, and if it is a solid acid such as stearic acid or a metal salt such as calcium chloride or copper chloride that reacts with ammonia to form a complex. Converts to a harmless, non-flammable substance.

When the treating agent is an ammonia decomposing catalyst such as iron alumina, nickel or platinum alumina and produces flammable hydrogen gas, the produced hydrogen is oxidized by the oxidizing agent to become harmless water. Or, it is widely diffused into the atmosphere by the air blower to avoid the danger of explosion.

[0013]

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.

The safety device for an ammonia absorption refrigerator according to the present invention comprises a closed container 8 made of a thin iron plate and a safety means 9 installed in this closed container.

As in the case of FIG. 4, the closed container 8 is the cold water heat exchanger 3, the hot water heat exchanger 4, the absorber 5 and the generator, except the indoor heat exchanger 1 and the outdoor heat exchanger 2 of the ammonia absorption refrigerator. The container 6 and the eight-way valve 7 are stored in a sealed state, for example, at atmospheric pressure,

The safety means 9 is installed on the top of the wall surface so that ammonia having a density lower than that of the atmosphere can be easily taken in from the closed container 8.

The safety means 9 of the safety device illustrated in FIG.
Predetermined pressure (for example, gauge pressure 0.3 kgf / cm ² )
As described above, the safety valve 91 of the type that ruptures and opens, the exhaust passage 92 installed on the downstream side, and the adsorbent (for example, activated carbon.
93) and a plurality of heat radiation fins 94 provided on the outer peripheral portion of the exhaust passage.

Since the ammonia vapor heated by the generator 6 has a high pressure of 10 kgf / cm ² or more, if a crack occurs in the pipe portion, for example, the ammonia gas causes the hermetically sealed container 8 to have an atmospheric pressure. Blow out inside,
The internal pressure of this closed container is increased.

When the internal pressure of the closed container 8 rises above a predetermined pressure (in this case, 0.3 kgf / cm ^{2 in} this case), the safety valve 91 bursts and opens, and ammonia is contained from the side of the closed high pressure container 8 side. Gas is exhausted to the exhaust passage 92,
Adsorbent 9 in which ammonia is the ammonia treating agent
Adsorbed and removed by 3.

For this reason, the gas exhausted to the atmosphere through the exhaust passage 92 in which the adsorbent 93 is installed does not contain ammonia, and has substantially the same composition as air. There is no danger of fire and there is no danger of fire. Further, the pressure in the closed container 8 does not rise abnormally and gradually drops.

Further, since a large number of heat radiation fins 94 are provided on the outer peripheral portion of the exhaust passage 92, even if a large amount of heat is generated when the adsorbent 93 adsorbs ammonia, there is no concern that this portion will become overheated. .

A protective lid 95 that opens at a pressure lower than the operating pressure of the safety valve is provided at the end of the exhaust passage 92 opposite the safety valve 91 to prevent the adsorbent 93 from contacting the atmosphere and deteriorating. It is also possible to do so.

Instead of the adsorbent 93, metal salts such as calcium chloride and copper chloride which react with ammonia to form a harmless complex, and solid acids such as stearic acid are used as the ammonia treating agent. It is also possible to install it in the exhaust passage 92.

In the safety device for an ammonia absorption refrigerator illustrated in FIG. 2, a decomposing agent capable of decomposing ammonia into hydrogen and nitrogen (for example, platinum) instead of the adsorbent 93 of the safety means 9 in FIG. In this example, an alumina catalyst 93a is installed in the exhaust passage 92, and an oxidant (for example, a hydrogen oxidation catalyst such as palladium alumina) 96 is installed downstream of the exhaust passage 92.

When a hydrogen oxidation catalyst such as palladium alumina is used as an oxidant as in this safety device,
A blower (not shown) for replenishing oxygen used for the reaction with hydrogen is preferably connected upstream of the oxidant 96.

By configuring the safety means 9 as described above,
Flammable hydrogen gas generated by decomposing agent 93a decomposing ammonia is oxidized by oxidizing agent 96 into water, which is extremely safe. Then, the remaining gas, that is, the gas having substantially the same composition as air diffuses into the atmosphere, and the internal pressure of the closed container 8 gradually decreases.

Further, instead of the oxidizing agent 96, the decomposing agent 9
By installing a diffusion pump 97 for blowing air on the downstream side of 3a and diffusing flammable hydrogen gas decomposed / generated by the decomposing agent 93a into a wide range by a large amount of air sent by the pump 97 or air with a high wind speed. As compared with diffusing hydrogen gas into the atmosphere at a very low speed, the safety can be remarkably enhanced.

Also in the case of the safety device shown in FIG. 2, the protective lid 95 having the above-mentioned function is installed, and the decomposing agent 93a and the oxidizing agent 9 are provided.
It is possible to prevent 6 from coming into contact with the atmosphere and deteriorating.

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

For example, the safety valve 91 has the above-described structure which surely ruptures and opens at a predetermined pressure, and as shown in FIG. 3, the valve plate 91c normally closes the opening 91b by the force of the spring 91a. When a pressure equal to or higher than a predetermined pressure acts to the right in the drawing, the valve plate 91c moves to the right and the opening 91
It is also possible to adopt a mechanism in which b is opened.

As the oxidizer for oxidizing the combustible hydrogen gas generated by decomposing ammonia, in addition to the catalyst such as palladium alumina shown in the embodiment, for example, CuO ₂ which reacts directly with hydrogen and is gradually oxidized. It may be an oxidizing agent such as.

Further, the radiation fin 94 need not be installed when a treatment agent which does not generate a large amount of heat when treating ammonia is selected.

It is also possible to install the safety means 9 inside the closed container 8 to form a compact structure. In this case, if the ammonia treatment agent installed in the exhaust passage 92 makes the ammonia a non-toxic and non-flammable substance, it is possible to release the gas after the treatment into the closed container 8, but When decomposing to produce flammable hydrogen gas, the open end side of the exhaust passage 92 needs to be communicated with the outside of the closed container 8 so that it can be released into the atmosphere. Then, as a means for cooling the reaction heat generated when processing the ammonia, it is preferable to use water cooling or the like instead of the radiation fins 94.

[0034]

As described above, the present invention is a safety means including a safety valve that opens at a predetermined pressure or more, an exhaust passage provided downstream of the safety valve, and an ammonia treating agent provided in the exhaust passage. The above is a safety device for an ammonia absorption refrigerator, in which a closed container surrounding a refrigerator of the ammonia absorption refrigerator is installed so as to be communicable via the safety valve.

A safety valve that opens above a predetermined pressure, an exhaust passage provided downstream of the safety valve, an ammonia decomposing agent installed in the exhaust passage, and an oxidizing agent or a blowing means installed downstream of the ammonia decomposing agent. A safety measure consisting of and in a closed container surrounding the refrigerator of the ammonia absorption refrigerator,
Since it is a safety device of the ammonia absorption refrigerator, which is installed so as to be able to communicate through the safety valve,

Even if the refrigerant pipe or the like is cracked, it is possible to reliably prevent diffusion of ammonia, which is the refrigerant, into the atmosphere. Further, when a large amount of reaction heat is generated during the treatment of ammonia, the radiation fins are installed in the safety means, so that this portion does not become overheated, which is a remarkable effect.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example.

FIG. 2 is an explanatory diagram of another embodiment.

FIG. 3 is an explanatory diagram of a safety valve.

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 Eight-way Valve 8 Closed Container 9 Safety Measures 91 Safety Valve 91a Spring 91b Opening 91c Valve Plate 92 Exhaust passage 93 Adsorbent 93a Decomposing agent 94 Radiating fin 95 Protective lid 96 Oxidizing agent 97 Diffusion pump P1, P2, P3 Pump T1, T2, T3, T4, T5 Temperature sensor SW1, SW2 Pressure switch V1, V2 Pressure reducing valve V3, V4 safety valve

Claims (2)

[Claims] 1. A refrigerator for an ammonia absorption refrigerator, comprising a safety means including a safety valve that opens at a predetermined pressure or more, an exhaust passage provided downstream of the safety valve, and an ammonia treating agent provided in the exhaust passage. A safety device for an ammonia absorption refrigerator, which is installed so as to be able to communicate with the closed container surrounding the above through the safety valve. 2. A safety valve that opens at a predetermined pressure or higher, an exhaust passage provided downstream of the safety valve, an ammonia decomposing agent installed in the exhaust passage, an oxidizer provided downstream of the ammonia decomposing agent, or A safety device for an ammonia absorption refrigerator, wherein a safety means composed of a blower means is installed in a closed container surrounding the refrigerator of the ammonia absorption refrigerator so as to be able to communicate with each other via the safety valve.