JPS5815703B2 - absorption refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an absorption refrigerator that uses water as a refrigerant and lithium bromide or lithium chloride as an absorption liquid, while achieving a cooling function below 0°C.

The methods currently used to obtain low temperatures below 0°C using absorption refrigerators include a water/ammonia type that uses ammonia as a refrigerant and water as an absorption liquid, and the other is an absorption refrigeration cycle that uses an inert gas. There are two types of inert gas mixed in.

However, Type 9 that contains inert gas is a refrigerator, etc.

Although it is widely used in relatively small-sized refrigerators, there are no examples of it being used in large-capacity refrigerators, and although the water/ammonia type can also be used in large-capacity refrigerators,
Due to the toxicity of ammonia, measures to prevent danger to users or careful operation and handling were required.

In addition, water H2 is used as the refrigerant (Lithium bromide Li B is used as the X absorption liquid)
In H2OLiBr-based absorption refrigerators that use r, water as a refrigerant freezes at 0°C, so cold water of about 3°C at most can be obtained, and it is mainly used for air conditioning that uses chilled water of about 5 to 10°C. It has been difficult to extract plines at temperatures below 0°C.

An object of the present invention is to solve the above problems by using water as a refrigerant and using lithium bromide or lithium chloride in the refrigerant so that the water in the refrigerant in the evaporator does not freeze even if the temperature drops below 0°C. The purpose of this invention is to provide an absorption refrigerator in which a freezing effect is obtained by mixing the liquid in a concentration lower than that of the absorption liquid and spraying the mixture into the evaporator.

Embodiments of an absorption refrigerator according to the present invention will be described below with reference to the drawings.

First, the conventional absorption refrigerator uses hot water or steam as a driving heat source to heat the dilute absorption liquid in the generator 1, as shown in
, cooling water 6 is used for cooling in the absorber 2 and condenser 3, and cold water 7 is taken out from the evaporator 4.
This is a so-called cold water absorption refrigerating machine that operates in a state where the temperature is lower than that of the condenser 3, and for example, a lithium bromide aqueous solution is used as the refrigerant/absorbing liquid of this absorption refrigerating machine.

Hot water or steam 5 flowing into such an absorption refrigerator as a driving heat source flows into a generator 1 and is disposed of, and cooling water 6 flowing into the absorption refrigerator 6 for cooling is converted into an absorption liquid and a refrigerant in an absorber 2 and a condenser 3, respectively. After being cooled, it is refluxed or discarded, and during this time, the state of the refrigerant in the absorption refrigerator changes according to the refrigeration cycle, so cold water 7 is taken out from the evaporator 4.

As shown in FIG. 2, the absorption refrigerating machine according to the present invention has a lower shell 21 with a low pressure absorber 12 and a low pressure generator 14 corresponding to an evaporator, and a lower shell 22 with a high pressure generator 11 and a condenser. A high-pressure absorber 13 is housed, and the high-pressure absorber 13 and the low-pressure waste generator 14 are pumped so that the refrigerant, that is, water mixed with an absorbing liquid such as lithium bromide or lithium chloride and diluted with the absorbing liquid, is circulated. 23 and a heat exchanger 24 to form a refrigerant system circulation cycle.
An absorption liquid system circulation cycle is configured by connecting via a pipe 2930 via a pump 27 and a heat exchanger 28 so that an absorption liquid having a slightly higher concentration than that used in the absorption refrigerator shown in the figure is circulated. In such a configuration, in the absorption liquid circulation cycle, hot water or steam 15 is supplied to the high pressure generator 11 and cooling water 16 is supplied to the low pressure absorber 12, as in the conventional absorption refrigerator shown in FIG. When the pump 27 is driven at the same time, the replenishing liquid that has absorbed the refrigerant is sent to the high pressure generator 11 via the heat exchanger 28, where it is heated by hot water or steam 15 and becomes a concentrated solution in which the refrigerant is separated from the absorbed liquid. The liquid flows into the low pressure absorber 12 via the heat exchanger 28 described above.

On the other hand, the refrigerant heated by hot water or steam 15 in the high-pressure generator 11 and separated from the absorption liquid of the absorption liquid system flows to the high-pressure absorber 13, where it is cooled by cooling water 16 and becomes the absorption liquid of the refrigerant system. Absorbed and mixed.

In addition, in the refrigerant system circulation cycle, the high pressure absorber 13
When pump 23 is driven while supplying cooling water 16 to
After being evaporated in step 4, it is sent to the high-pressure absorber 13 via the heat exchanger 24.

In the conventional absorption refrigerator shown in Fig. 1, the refrigerant condensed in the condenser 3 is completely evaporated in the evaporator 4, and ideally, the refrigerant does not contain any lithium bromide, etc. In this cycle, a certain concentration of lithium bromide etc. is mixed into the refrigerant and circulated, so the low pressure generator 1
4, the evaporated refrigerant flows out into the low-pressure absorber 12, and the remaining absorption liquid of the refrigerant system flows into the high-pressure absorber 13 with a slightly increased concentration.

The low-pressure generator 14 in FIG. 2, which corresponds to the evaporator 4 in FIG. 1, includes a cooler 32 that is cooled by evaporation of a refrigerant. The plines flowing through the cooler are cooled while the refrigerant flows down in the form of a thin film.

On the other hand, the low pressure absorber 1 is heated and separated by the low pressure generator 14.
The refrigerant that has flowed into the cooling water 1
6, and is absorbed into the absorption liquid of the absorption liquid system.

In this way, the refrigeration cycle between the circulation cycles of the absorption liquid system and the refrigerant system described above is repeated.

FIG. 3 is a Duering diagram showing the two circulation cycles of the above-mentioned absorption liquid system and refrigerant system, where A is the circulation cycle of the absorption liquid in the absorption liquid system and B is the circulation cycle of the absorption liquid in the refrigerant system. An example of the operation of temperature ℃ - positive pressure tHy is shown.

In the low pressure generator 14 as shown in B, 25%
Li Br aqueous solution with a concentration of brine 17 (0°C → -5
The absorption refrigerator is the same as the absorption refrigerator shown in FIG. 1 in that it is heated at a temperature of 10.degree.

At this time, the generated pressure is 2.5 xwHg, the concentration is increased from 25% to 30%, and the generated temperature is -6°C.

It goes without saying that the concentrated concentration of the refrigerant is determined by the wettability of the heat transfer surface, etc.

On the other hand, as shown in A, the generated refrigerant is transferred to the low pressure absorber 1.
2 and is absorbed at an absorption temperature of 20°C.

The temperature of the cooling water 16 at this time is relatively low, from 13°C to 18°C.

In addition, the absorption liquid is heated to hot water or steam 15 in a high pressure generator 11.
(95°C→90°C) to generate a refrigerant, which is absorbed by the adjacent high-pressure absorber 13, and the absorbed heat is discharged to the outside by cooling water 16 (35°C→40°C).

As shown in B, the refrigerant-based absorption liquid whose concentration has decreased in the high-pressure absorber 13 passes through the heat exchanger 24 and heads toward the low-pressure generator 14 .

In the above embodiments, lithium bromide or lithium chloride was used as the absorption liquid, but an antifreeze agent such as ethylene glycol may be added.

As can be understood from the above-mentioned Dühring diagram, the absorption refrigerator according to the present invention does not use any special refrigerant or absorption liquid, but by changing the composition of the conventionally widely used refrigerant and absorption liquid, the water that is the refrigerant freezes. This makes it possible to obtain prine at a temperature of 0°C or lower without having to do so, and also to produce ice, etc. using the same prine.

[Brief explanation of the drawing]

FIG. 1 is a diagrammatic explanatory diagram of a conventional absorption refrigerator, FIG. 2 is a diagrammatic explanatory diagram of an embodiment of an absorption refrigerator according to the present invention, and FIG. 3 is a diagrammatic explanatory diagram of an embodiment of an absorption refrigerator according to the present invention. An overview of the Duering diagram when operated by a lithium bromide aqueous solution is shown. 1... Generator, 2... Absorber, 3... Condenser, 4
... Evaporator, 5... Hot water or steam, 6... Cooling water, 7... Cold water, 11... High pressure generator, 12...
Low pressure absorber, 13... High pressure absorber, 14... Low pressure generator, 15... Hot water or steam, 16... Cooling water,
17... Pline, 23... Pump, 24... Heat exchanger, 27... Pump, 28... Heat exchanger, 32
···Cooler.

Claims (1)

[Claims] 1. An absorption system that uses water as the refrigerant and lithium bromide or lithium chloride as the absorption liquid, and has a closed circulation cycle between the refrigerant and the absorption liquid by connecting the generator, condenser, evaporator, absorber, etc. with pipes. An absorption refrigerating machine which forms a refrigerating machine, and an evaporator of the absorption refrigerating machine is mixed with an absorption liquid and a refrigerant is sprayed thereon.