JPH02267474A - Double effect air-cooled absorption type refrigerator - Google Patents

Abstract

PURPOSE:To enable a refrigerant piping system to be performed most appropriately by a method wherein in case that a liquid surface of an air-cooled condensor is placed at a lower position than that of a liquid surface in an evaporator, condensing refrigerant is returned back to the evaporator by a pump and another refrigerant in the evaporator is returned back from a dam means to an air-cooled absorber device through a piping system. CONSTITUTION:A refrigerant pump 6 is arranged in a refrigerant returning pipe 5 as means for feeding refrigerant having a capability to exceed a working pressure liquid column height. A condensed refrigerant is returned from an air-cooled condensor 3 to an evaporator 1 under a pump operating power. When solution shows a high concentration and the refrigerant is abnormally separated, the refrigerant is overflown over an opening dam 9 formed at a refrigerant container of the evaporator 1. The refrigerant passes an over-flow pipe 10, the refrigerant flows to the solution container of an air-cooled absorber device 14 so as to dilute the solution. With such an arrangement as above, a liquid surface 2 of the evaporator is higher than a liquid surface 4 of the air-cooled condensor. Even in case that it is higher than a differential pressure liquid column head, the liquid refrigerant can be returned positively from the air-cooled condensor 3 to the evaporator 1. The refrigerant over-flow in the evaporator 1 in properly attained and then a double-effected air-cooled absorption type refrigerator can be operated safely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dual effect air-cooled absorption refrigerating machine, and in particular to a refrigerant flow in a configuration in which the air-cooled condenser liquid level is located in a lower part of the overall device. The present invention relates to a dual-effect air-cooled absorption refrigerator with a reduced number of refrigerant piping systems suitable for return path and overflow functions.

[Prior Art] In conventional water-cooled absorption refrigerators, the liquid level of the condenser is located at a higher level than the liquid level of the evaporator, and a position head returns the condensed refrigerant to the evaporator.

For example, according to "Absorption Chiller and Its Applications" (edited by Japan Refrigeration Association, published October 20, 1972), Figure 55 on P.33, Figure 2 on P.45, P.60 Figure 2
As shown in Figure 2 of , P. 75, in all absorption refrigeration cycles, the condenser is installed higher than the evaporator, and the position head returns the condensed refrigerant from the condenser to the evaporator. Ta.

[Problem to be solved by the invention] In water-cooled absorption chillers, the cooling is performed using cooling water from a cooling tower, which requires installation work, maintenance, and water management costs, so the development of air-cooled absorption chillers has been rapid. We were able to proceed.

For example, as an air-cooled absorption water chiller using water as a refrigerant and lithium bromide as an absorbent, JP-A-61-49970
The technology described in the above publication has been developed, and uses a configuration in which fins are provided outside the vertical tube so that the absorber and condenser are cooled by air flow from a fan.

By the way, when changing from a water-cooled type to an air-cooled type and the liquid level of the air-cooled condenser is at a lower part of the entire device, when operating at the specified point, the condensed refrigerant flows into the evaporator due to the pressure difference between the air-cooled condenser and the evaporator. To return to this point, there was a problem in that when the pressure difference was small, such as during low load or startup, the condensed refrigerant could not be returned to the evaporator.

In addition, if the load is high and the operation is higher than the rated (specification point), there is a risk that the solution will become highly concentrated and enter the crystalline region, and in this case, the amount of refrigerant in the evaporator may exceed the set point. In the air-cooled absorption refrigerator, the refrigerant cannot be sent to the air-cooled absorber simply by gravity, and requires a refrigerant overflow means, and the overflow does not function properly.

The present invention was made to solve the problems in the prior art described above, and includes a refrigerant return system that returns condensed refrigerant to the evaporator when the liquid level of the air-cooled condenser is lower than the liquid level of the evaporator; It is an object of the present invention to provide a dual-effect air-cooled absorption refrigerator that allows a refrigerant piping system of a refrigerant overflow system to function optimally.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the first invention of the dual-effect air-cooled absorption refrigerator according to the present invention includes an evaporator, an air-cooled absorber, an air-cooled condenser, and a low-temperature It consists of a regenerator, a high temperature regenerator, a solution heat exchanger, a solution circulation pump, a refrigerant spray pump, and a piping system that operatively connects them. In the dual-effect air-cooled absorption chiller, the evaporator is located higher than the air-cooled condenser in the middle of the refrigerant return pipe that connects the air-cooled condenser and evaporator, so that the liquid level of the air-cooled condenser and the liquid level of the evaporator are separated. The evaporator is provided with a refrigerant supply means for when the difference in height between the two and A refrigerant pipe is provided for returning the refrigerant from the weir means to the air-cooled absorber or solution system.

In addition, a second invention of the dual-effect air-cooled absorption refrigerator according to the present invention includes an evaporator, an air-cooled absorber, an air-cooled condenser, a low-temperature regenerator, a high-temperature regenerator, a solution heat exchanger, and a solution circulation pump. ,
In a dual-effect absorption refrigerator comprising a refrigerant spray pump and a piping system operatively connecting these, and a fan supplying cooling air to the air-cooled absorber and air-cooled condenser, the refrigerant container of the evaporator is Equipped with a communicating refrigerant tank,
A liquid level switch is provided so that the refrigerant liquid level can be maintained at approximately the same level as the liquid level of the air-cooled condenser, and a U-shaped refrigerant return pipe is provided that connects the air-cooled condenser and the refrigerant tank. A refrigerant spray pipe connected to the refrigerant tank and equipped with a refrigerant spray pump, and a refrigerant blow pipe branched from the refrigerant spray pipe and equipped with a solenoid valve and connected to the air-cooled absorber or a part of the solution system, The solenoid valve is opened and closed by a signal from a liquid level switch.

Furthermore, the third aspect of the dual effect air-cooled absorption refrigerator according to the present invention is
The invention consists of an evaporator, an air-cooled absorber, an air-cooled condenser, a low-temperature regenerator, a high-temperature regenerator, a solution heat exchanger, a solution circulation pump, a refrigerant spray pump, and a piping system operatively connecting these. , the dual-effect air-cooled absorption refrigerator equipped with a fan for supplying cooling air to the air-cooled absorber and the air-cooled condenser, including a refrigerant tank communicating with the refrigerant container of the evaporator, and the refrigerant tank serving as the main refrigerant tank. The auxiliary refrigerant tank is integrally formed with an auxiliary refrigerant tank having a cross-sectional area smaller than the cross-sectional area of the main refrigerant tank, and the auxiliary refrigerant tank includes a weir means for overflowing when the refrigerant exceeds a set liquid level, and an air-cooling absorption system from the weir means. A U-shaped refrigerant pipe connecting the air-cooled condenser and the refrigerant tank is provided, and the overflow weir is placed higher than the liquid level of the air-cooled absorber at the lowest concentration of the solution. A refrigerant return pipe is provided.

[Operation] The first invention is a technical means when the evaporator liquid level is higher than the liquid level of the air-cooled condenser and higher than the differential pressure liquid column head.

In this case, the condensed refrigerant is returned from the air-cooled condenser to the evaporator by a refrigerant supply means such as a refrigerant pump or a refrigerant ejector. Also, refrigerant overflow in the evaporator is provided by an open base and refrigerant overflow piping to return refrigerant to the air-cooled absorber or solution system.

The second invention is a technical means when the evaporator liquid level is at the same level as the air-cooled condenser liquid level.

In this case, the condensed refrigerant easily flows to the evaporator side refrigerant tank through the U-shaped refrigerant return pipe. but.

In order to flow the refrigerant overflow to avoid crystals to the air-cooled absorber located approximately at the same location as the air-cooled condenser (or
In order to prevent the solution from flowing back into the piping system), the refrigerant is returned to the air-cooled absorber or solution system by the refrigerant blow piping via a refrigerant supply means such as a refrigerant spray pump.

A third invention is the first invention. This is a technical means when the evaporator or the auxiliary refrigerant tank is located at an intermediate position in the case of the second invention.

In this case, the condensed refrigerant flows to the evaporator-side refrigerant tank through the U-tubular refrigerant return pipe at the operating operating pressure differential with the position head. For refrigerant overflow, an opening for overflow is provided in the auxiliary refrigerant tank at a position higher than the maximum liquid level of the air-cooled absorber, and the refrigerant is returned to the air-cooled absorber or solution system through a refrigerant overflow piping.

[Example] Hereinafter, each example of the present invention will be described with reference to FIGS. 1 to 5.

FIG. 1 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to an embodiment of the first invention.

In FIG. 1, 1 is an evaporator, 2 is an evaporator liquid level, 3 is an air-cooled condenser, 4 is an air-cooled condenser liquid level, 5 is a refrigerant return pipe connecting the air-cooled condenser 3 and the evaporator 1, 6 is the refrigerant return pipe 5
7 is a bypass pipe, 8 is an orifice provided in the bypass pipe 7, 9 is an opening group related to an overflow weir means provided in the refrigerant container of the evaporator 1, 10 is an overflow pipe leading from the opening base 9 to the air-cooled absorber 14, 11 is a refrigerant spray pump, 12 is a refrigerant spray pipe, 14 is an air-cooled absorber,
15 is a high temperature regenerator, 16 is a low temperature regenerator, 17 is a fan that supplies cooling air to the air-cooled condenser 3 and the air-cooled absorber 14, 25 is a cold water pipe passing through the evaporator 1, and 26 is the evaporator 1 27 is a solution circulation pump, 28 is a dilute solution pipe that connects the solution container of the air-cooled absorber 14 and the solution heat exchanger 29, 29 is a solution heat exchanger, 3
0 is a dilute solution pipe that connects the solution heat exchanger 29 and the high temperature regenerator 15, 31 is a dilute solution pipe that connects the solution heat exchanger 29 and the low temperature regenerator 16, 32 is a refrigerant vapor pipe, and 33 is a vapor passage. ,3
4 is a concentrated solution tube that connects the high temperature regenerator 15 and the solution heat exchanger 29, 35 is a concentrated solution tube that connects the low temperature regenerator 16 and the solution heat exchanger 29, and 36 is an air cooling tube that connects the solution heat exchanger 29 and the solution heat exchanger 29. This is a concentrated solution pipe that connects to the absorber 14.

First, the basic cycle operation of such a dual-effect air-cooled absorption refrigerator will be explained.

The refrigerant (water) in the evaporator 1 is supplied by a refrigerant spray pump 11,
The refrigerant is sprayed onto the cold water pipe 25 through which the cold water passes through the refrigerant spray pipe 12, removes evaporation heat from the cold water, becomes low-pressure refrigerant vapor, and flows into the air-cooled absorber 14 through the steam passage 26.

The air-cooled absorber 14 is air-cooled by a fan 17, and the refrigerant vapor is dispersed from the top and absorbed into a concentrated lithium bromide solution flowing down the vertical pipe, thereby becoming a dilute solution.

This dilute solution is sent out through a dilute solution pipe 28 by a solution circulation pump 27, passes through a solution heat exchanger 29, and then passes through a dilute solution pipe 3.
0.31 to the high temperature regenerator 15° and the low temperature regenerator 16.

The high temperature regenerator 15 is supplied with an external heat source, and uses the combustion heat of the furnace 15a to condense the dilute solution and generate steam. The generated refrigerant vapor heats and concentrates the dilute solution in the low-temperature regenerator 16 via the heat transfer tube portion 16a of the refrigerant vapor pipe 32.

Steam generated from the concentrated dilute solution in the low-temperature regenerator 16 flows into the vertical pipe of the air-cooled condenser 3 through the steam passage 33, is air-cooled by the fan 17, condenses and liquefies, and becomes a liquid refrigerant. The refrigerant returns from the container to the refrigerant container of the evaporator 1 via the refrigerant return pipe 5.

High temperature regenerator 15. The solutions concentrated in the low-temperature regenerator 16 are sent to the upper header of the air-cooled absorber 14 via the concentrated solution pipe 36 after passing through the solution heat exchanger 29 via the concentrated solution pipes 34 and 35, where they are dispersed and again undergo the absorption process. is repeated.

Next, the characteristic points of this embodiment will be explained in more detail.

During operation, the evaporator liquid level 2 is lower than the air-cooled condenser liquid level 4 by the operating pressure difference (for example, condenser 50 mHg - evaporator 7 mHg =
42 nn+Hg=571 mmAg) or higher. At the differential pressure between the two, the condensed refrigerant flows from the air-cooled condenser 3 to the evaporator 1.
I won't go back.

Therefore, in the embodiment shown in FIG. 1, a refrigerant pump 6 is provided in the refrigerant return pipe 5 as a refrigerant supply means with a capacity exceeding the working pressure liquid column height, and the pump power supplies the condensed refrigerant to the air-cooled condenser 3.
The liquid is then returned to the evaporator 1.

In order to balance the suction pressure of the refrigerant pump 6 and prevent recavitation, a bypass pipe 7 is provided with an orifice 8 (or throttle valve) before and after the refrigerant pump 6.
has been established.

On the other hand, when the solution becomes highly concentrated and the refrigerant is abnormally separated, the refrigerant overflows through the opening base 9 formed in the refrigerant container of the evaporator 1, and the refrigerant passes through the overflow pipe 10 into the solution in the air-cooled absorber 14. Flow into the container section to dilute the solution.

According to the embodiment of FIG. 1, even if the evaporator liquid level 2 is higher than the air-cooled condenser liquid level 4 and higher than the differential pressure liquid column head, the liquid refrigerant is transferred from the air-cooled condenser 3 to the evaporator 1. In addition to being able to reliably return the refrigerant, the refrigerant overflow in the evaporator 1 can be made to function properly, and the dual effect air-cooled absorption refrigerator can be operated safely.

In the embodiment shown in FIG. 1, an example has been described in which all the overflowed refrigerant is sent to the air-cooled absorber, but the solution may be diluted by returning it to another solution system.

Next, FIG. 2 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to another embodiment of the first invention. In FIG. 2, parts with the same reference numerals as in FIG. 1 are equivalent parts, so their explanation will be omitted.

The difference between the embodiment shown in FIG. 2 and the embodiment shown in FIG. 1 is as follows.
As a refrigerant supply means, a refrigerant return pipe 5A from the air-cooled condenser 3 and a refrigerant spray pump 1 of the refrigerant spray pipe 12 are used.
1 through a refrigerant ejector 13.

According to the embodiment of FIG. 2, the condensed refrigerant is
3, the refrigerant can be returned to the evaporator 1 via the refrigerant spray pipe 12, and the same effects as those described in the embodiment shown in FIG. 1 can be expected.

Next, FIG. 3 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to an embodiment of the second invention. In Figure 3,
Components with the same reference numerals as those in FIG. 1 are equivalent parts, so a description thereof will be omitted.

In FIG. 3, 18 is a refrigerant tank communicating with the refrigerant container of the evaporator 1, and the refrigerant liquid level 2' (
(corresponding to the evaporator liquid level) is provided at a position where it can be maintained at approximately the same level as the air-cooled condenser liquid level 4. 19 is an air-cooled absorber liquid level; 20 is a liquid level switch for controlling the refrigerant liquid level 2' to the same level as the air-cooled condenser liquid level 4; 21 is a solenoid valve; 23
is a refrigerant blow pipe that branches from the refrigerant spray pipe 12B, is provided with a solenoid valve 21, and is connected to the air-cooled absorber 14.

In the dual-effect air-cooled absorption refrigerator shown in FIG. 3, when the operation starts, the condensed refrigerant accumulates in the refrigerant container of the air-cooled condenser 2, and the liquid level becomes high, and the refrigerant passes through the U-shaped refrigerant return pipe 5B to the refrigerant tank. Return to 18. In addition, differential pressure is generated due to operation,
It also returns due to the pressure.

On the other hand, since the air-cooled absorber liquid level 19 is approximately at the same level, if an overflow pipe is provided from the refrigerant liquid level of the refrigerant tank, the solution will flow back and the refrigerant will be contaminated.

Therefore, a liquid level switch 20 is provided as a liquid level sensor at the refrigerant liquid level 2' (set liquid level height) of the refrigerant tank 18.

When the refrigerant liquid level 2' rises, the solenoid valve 21 is opened by the signal from the liquid level switch 20, and the refrigerant is air-cooled and absorbed by the power of the refrigerant spray pump 11 through the refrigerant blow piping 23 from a high position where there is no risk of backflow of the solution. Flow to vessel 14 to dilute the solution.

According to the embodiment shown in FIG. 3, even if the refrigerant liquid level 2' of the refrigerant tank 18 corresponding to the evaporator liquid level is at the same level as the air-cooled condenser liquid level 4, the liquid refrigerant is transferred from the air-cooled condenser 3 to the evaporator. It is possible to reliably return the refrigerant to the refrigerant tank 18 on the first side, and also to reliably send the refrigerant exceeding the set refrigerant liquid level to the air-cooled absorber 14 without backflow of the solution, thus fulfilling the refrigerant overflow function.
A dual-effect air-cooled absorption chiller can be operated safely.

Next, FIG. 4 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to an embodiment of the third invention. In the figure, the first
Figures with the same numbers as in Figure 3 are shown.

Since the parts are equivalent to those of those embodiments, the explanation thereof will be omitted.

In the embodiment shown in FIG. 4, the refrigerant liquid level in the refrigerant tank during operation is located between the evaporator liquid level 2 in FIG. 1 and the refrigerant liquid level 2' in the refrigerant tank in FIG. It is.

In FIG. 4, 18' is a refrigerant tank communicating with the refrigerant container of the evaporator 1, and this refrigerant tank 18' consists of a main refrigerant tank and an auxiliary refrigerant tank 18a having a cross-sectional area smaller than that of the main refrigerant tank. It is integrally formed. The refrigerant liquid level 2' in this auxiliary refrigerant tank 18a is at a level Hmm Ag higher than the air-cooled condenser liquid level 4.

The refrigerant tank 18' has a refrigerant at the top of the main refrigerant tank so that when the load is low, the refrigerant liquid level is approximately the same height as the liquid level of the air-cooled condenser 14, and when the load is high, the refrigerant liquid level becomes higher. An auxiliary refrigerant tank 18a with a small cross-sectional area is formed.

9A is an opening base provided in the auxiliary refrigerant tank 18a, and the opening base 9A is a weir means that overflows when the refrigerant exceeds a set liquid level. IOA is an overflow pipe that connects from the open base 9A to the air-cooled absorber 14. The open group 9A is located at the air-cooled absorber liquid level 19. when the solution has the lowest concentration. That is, it is arranged higher than the maximum liquid level height of the air-cooled absorber 14.

In the dual-effect air-cooled absorption refrigerator shown in FIG. 4, the air-cooled condenser liquid level 4 is HmaAg lower than the refrigerant liquid level 2' in the auxiliary refrigerant tank, as described above. Therefore, when the pressure difference between the two sections during operation exceeds H/13,6 nnHg, the condensed refrigerant flows from the air-cooled condenser 3 to the refrigerant tank 18' via the U-shaped refrigerant return pipe 5B (for example, H=
Assuming 200■Ag, the pressure difference is 14,7 nmHg
). Needless to say, until the refrigerant flows into the refrigerant tank 18', the refrigerant accumulates in the refrigerant container of the air-cooled condenser 3, the liquid level rises, and H eventually becomes small.

In addition, in the case of abnormal separation of refrigerant, the auxiliary refrigerant tank 18
Let the refrigerant overflow from the opening base 9A provided in a,
The refrigerant is transferred to the air-cooled absorber 1 through the overflow pipe 10A.
Dilute the solution back to step 4.

At this time, as described above, since the opening group 9A is arranged higher than the maximum liquid level height of the absorber, the refrigerant is not contaminated by the backflow of the solution.

Next, FIG. 5 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to still another embodiment of the first invention. In the figure, parts with the same reference numerals as those in FIG. 1 are the same parts as in the embodiment of FIG. 1, and therefore their explanation will be omitted.

The embodiment shown in FIG. 5 differs from the embodiment shown in FIG. 1 in that instead of using bypass piping in the embodiment shown in FIG. 1 to prevent cavitation of the refrigerant pump 6,
A liquid level switch 22 is provided in the refrigerant container of the air-cooled condenser 3, and a flow rate control valve 24 that interlocks with the liquid level switch 22 is provided on the refrigerant pump 6 discharge side of the refrigerant return pipe 5C to control the circulation amount of the refrigerant return pipe 5C. This is to prevent cavitation.

That is, when the air-cooled condenser liquid level 4 decreases, the refrigerant pump 6
Since there is a risk that cavitation may occur, the liquid level is detected by the liquid level switch 22, and when the liquid level drops, the opening degree of the flow rate control valve 24 is reduced to control the amount of refrigerant circulation.

According to the embodiment shown in FIG. 5, the same effects as described in FIG. 1 can be expected.

[Effects of the Invention] As described above, according to the present invention, when the liquid level of the air-cooled condenser is lower than the liquid level of the evaporator, the refrigerant return system returns the condensed refrigerant to the evaporator, and the refrigerant overflow It is possible to provide a dual-effect air-cooled absorption refrigerator that allows the refrigerant piping system of the system to function optimally.

[Brief explanation of drawings]

FIG. 1 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to an embodiment of the first invention, and FIG. 2 is a cycle diagram of a dual-effect air-cooled absorption refrigerator according to another embodiment of the first invention. A cycle system diagram of a refrigerator, FIG. 3 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to an embodiment of the second invention, and FIG.
FIG. 5 is a cycle system diagram of a dual-effect air-cooled absorption refrigerator according to yet another embodiment of the first invention. It is. 1... Evaporator, 2... Evaporator liquid level, 2', 2'...
・Refrigerant liquid level, 3... Air-cooled condenser, 4... Air-cooled condenser liquid level, 5.5A, 5C... Refrigerant return pipe, 5B,...
・U-shaped refrigerant return pipe, 6...refrigerant pump, 7...
Bypass piping, 8... Orifice, 9,9A... Opening group, 10° 10A... Overflow piping, 11.
... Refrigerant spray pump, 12.12B... Refrigerant spray piping, 13... Refrigerant ejector-14... Air-cooled absorber, 15... High-temperature regenerator, 16... Low-temperature regenerator,
17... Fan, is, is'... Refrigerant tank, 1
8a... Auxiliary refrigerant tank, 19... Air-cooled absorber liquid level, 20.22... Liquid level switch, 23... Refrigerant blow piping, 24... Flow rate control valve, 27... Solution circulation Pump, 29...solution heat exchanger.

Claims (1)

[Claims] 1. An evaporator, an air-cooled absorber, an air-cooled condenser, a low-temperature regenerator, a high-temperature regenerator, a solution heat exchanger, a solution circulation pump, a refrigerant spray pump, and a piping system that operatively connects these. In a dual-effect air-cooled absorption refrigerator comprising a fan that supplies cooling air to the air-cooled absorber and air-cooled condenser,
In the middle of the refrigerant return piping that connects the air-cooled condenser and evaporator, the evaporator is located higher than the air-cooled condenser, and the difference in height between the liquid level in the air-cooled condenser and the liquid level in the evaporator is caused by differential pressure. In addition to providing a refrigerant supply means in case the column height exceeds the column height, the evaporator is provided with:
A dual-effect air-cooled absorption refrigeration system characterized by having a weir means that overflows when the working liquid level becomes higher than a preset refrigerant liquid level, and a refrigerant pipe that returns the refrigerant from the weir means to the air-cooled absorber or solution system. Machine. 2. In the device described in claim 1, the refrigerant supply means is provided with a refrigerant pump in the refrigerant return pipe connecting the air-cooled condenser and the evaporator, and an orifice is provided before and after the refrigerant pump. A dual-effect air-cooled absorption refrigerator characterized by having a bypass pipe. 3. In the device described in claim 1, the refrigerant supply means is characterized in that the refrigerant return pipe from the air-cooled condenser is connected to the refrigerant spray pump discharge side of the refrigerant spray pipe via a refrigerant ejector. A dual-effect air-cooled absorption chiller. 4. In the item described in claim 1, a liquid level switch is provided in the refrigerant liquid container of the air-cooled condenser, and is interlocked with the liquid level switch on the refrigerant pump discharge side of the refrigerant return pipe from the air-cooled condenser. A dual-effect air-cooled absorption refrigerator characterized by being equipped with a flow control valve. 5. Consists of an evaporator, an air-cooled absorber, an air-cooled condenser, a low-temperature regenerator, a high-temperature regenerator, a solution heat exchanger, a solution circulation pump, a refrigerant spray pump, and a piping system operatively connecting these; In a dual-effect air-cooled absorption chiller equipped with a fan that supplies cooling air to an air-cooled condenser and an air-cooled condenser,
A refrigerant tank communicating with the refrigerant container of the evaporator is provided, and a liquid level switch is provided to maintain the refrigerant liquid level at approximately the same level as the liquid level of the air-cooled condenser, and the air-cooled condenser and the refrigerant tank are connected to each other. In addition to providing a U-shaped refrigerant return pipe for connection, a refrigerant spray pipe connected to the refrigerant tank and equipped with a refrigerant spray pump, and a refrigerant spray pipe branching from this refrigerant spray pipe and equipped with a solenoid valve to connect the air-cooled absorber or solution system. A dual-effect air-cooled absorption refrigerator, characterized in that a refrigerant blow pipe is connected to a part of the refrigerator, and the solenoid valve is opened and closed by a signal from the liquid level switch. 6. Consists of an evaporator, an air-cooled absorber, an air-cooled condenser, a low-temperature regenerator, a high-temperature regenerator, a solution heat exchanger, a solution circulation pump, a refrigerant spray pump, and a piping system operatively connecting these; In a dual-effect air-cooled absorption chiller equipped with a fan that supplies cooling air to an air-cooled condenser and an air-cooled condenser,
A refrigerant tank communicating with a refrigerant container of the evaporator is provided, and the refrigerant tank is integrally formed with a main refrigerant tank and an auxiliary refrigerant tank having a cross-sectional area smaller than the cross-sectional area of the main refrigerant tank, and the auxiliary refrigerant tank includes: A weir means that overflows when the refrigerant exceeds a set liquid level, and refrigerant piping that connects the weir means to the air-cooled absorber are provided, and the overflow weir has a level that is higher than the liquid level of the air-cooled absorber when the solution has the lowest concentration. 1. A dual-effect air-cooled absorption refrigerating machine, characterized in that a U-shaped refrigerant return pipe is arranged at a high height and connects the air-cooled condenser and the refrigerant tank.