JPH0567866B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an air-cooled absorption type water chiller/heater, and relates to the operating point of a refrigeration cycle and the structure of an absorber.

[Background of the invention]

In the conventional air-cooled absorption water chiller,
As described in No. 208559, refrigerant vapor is absorbed while an absorption liquid flows down along the inner wall of a group of vertical tubes in an absorber provided with fins on the outside. In this case, there was a problem in that it was very difficult to bring the temperature of the solution exiting the absorber close to the temperature of the cooling air.

The high temperature of the absorber outlet solution causes crystallization of lithium bromide, so it was essential to lower the solution outlet temperature of the air-cooled absorber.

[Purpose of the invention]

An object of the present invention is to provide an absorption water cooler that cools an absorber and a condenser with outdoor air.

[Summary of the invention]

In order to realize an air-cooled absorber, the present invention provides a heat exchange section with the liquid refrigerant liquefied in the condenser, that is, a second absorber, downstream of the air-cooled section, and a high-temperature regenerator made of corrosion-resistant metal or ceramic. etc. to raise the temperature of the high-temperature regenerator and increase the degree of subcooling in the condenser. A pressure reducer is installed in the liquid refrigerant system, and the temperature is lowered by evaporating some of the refrigerant by reducing the pressure. A gas-liquid separator is installed in the liquid refrigerant system after heat exchange, and only the liquid flows to the evaporator, while the vapor flows directly to the absorber.In the air cooling section, the cycle system and cooling air flow in countercurrents. .

[Embodiments of the invention]

An embodiment of the present invention will be explained with reference to FIG. The absorption type water chiller/heater 1 includes a high temperature regenerator 2, a low temperature regenerator 3, a condenser 4, an evaporator 5, an absorber 6, a solution heat exchanger 7, a burner 9, a solution pump 10, and a refrigerant pump 1.
Consisting of 2. The lithium bromide aqueous solution in the high temperature regenerator 2 is heated by the burner 9 to generate refrigerant vapor and the solution is concentrated. The generated refrigerant vapor flows into the heating pipe 14 of the low temperature regenerator 3 through the refrigerant line 13. The aqueous solution of lithium bromide in the low-temperature regenerator 3 is heated by the refrigerant vapor in the heating tube 14, and refrigerant vapor is also generated here. Here, the refrigerant in the heating tube 14 is liquefied, and the lithium bromide aqueous solution is concentrated.

The refrigerant vapor generated in the low temperature regenerator 3 enters the condenser 4 through the refrigerant flow path 15, while the liquefied refrigerant flows into the evaporator 5 from the refrigerant line 21 through the refrigerant line 16. The condenser 4 has fins 18 outside the tube, and since outdoor air flows through the fins 18 by a fan 19, the refrigerant vapor in the condenser 4 is cooled and liquefied.

Since the high-temperature regenerator 2 is made of a corrosion-resistant metal or a corrosion-resistant non-metal such as ceramic, the solution temperature in the high-temperature regenerator 2 can be higher than that of a conventional absorption type water cooler/heater. Therefore, the temperature and pressure of the refrigerant vapor flowing into the heating tube 14 through the refrigerant line 13 are higher than in the conventional case. As a result, the solution temperature in the low-temperature regenerator 3 also rises, and the temperature increases from the refrigerant line 15 to the condenser 4.
The temperature and pressure of the refrigerant vapor entering the system also increases.

For this reason, the condensation pressure in the condenser 4,
The condensation temperature also decreases, and as a result, the degree of subcooling of the liquid refrigerant becomes extremely large.

This supercooled refrigerant enters the second absorber 62 located at the lower part of the absorber 6 from the refrigerant line 17, and exchanges heat with the dilute solution leaving the absorber 6 or with the dilute solution partially flowing together with the refrigerant vapor, The refrigerant line 71 joins the refrigerant line 26 and flows from the refrigerant line 21 into the evaporator 5 .

There is a cold water pipe 22 in the evaporator 5, and liquid refrigerant is sprayed onto the cold water pipe 22 from a sprayer 23. Since the inside of the evaporator 5 is maintained under reduced pressure, the liquid refrigerant evaporates and its latent heat is taken away from the cold water in the cold water pipe. The liquid refrigerant that has not completely evaporated accumulates in the refrigerant reservoir 24 and is transferred to the refrigerant line 25 and the refrigerant pump 1.
2. The refrigerant vapor that returns to the spargeer 23 again through the refrigerant line 26 enters the absorber 6 through the refrigerant flow path 48.

The absorber 6 includes a vertical pipe 28 and fins 2 outside the pipe.
It consists of 9.

Further, there is a sprayer 30 at the top of the vertical pipe 28, and the concentrated solution that has passed through the concentrated solution line 31 is sprayed from the sprayer 30. The sprayed concentrated solution is cooled by outdoor air flowing outside the tube while flowing down along the wall of the vertical tube 28, and its water vapor pressure decreases. There, it absorbs the refrigerant vapor from the evaporator 5 and becomes a dilute solution.

There is a duct 32 around the absorber 6, which wraps around the absorber 6 and becomes the suction duct for the fan 20. An air passage 34 is formed between the absorber vertical pipe 28 and the duct 32, and the rotation of the fan 20 generates an upward wind in the air passage 34, and the absorber fin 29 and the vertical pipe 28 are cooled by this wind. Ru. Moreover, the air flowing through the air passage 34 is
Outdoor air is absorbed through the

Thus, in the absorber 6, the solution and refrigerant vapor flow and the cooling air flow are countercurrent, increasing the efficiency of the absorber 6 and thus realizing an air-cooled absorber. Additionally, slits 35 are provided to improve heat transfer in the fins 28. Furthermore, the vertical pipe 28
A spiral plate or padding (not shown) is placed inside to improve contact between the concentrated solution and the tube wall and between the concentrated solution and the refrigerant. Additionally, the inner surface of the vertical tube 28 may be provided with fins or grooves (not shown) to improve intra-tube heat transfer.

The dilute solution leaving the absorber 6 is further transferred to the second absorber 6.
Enter 2. Here, the dilute solution or the dilute solution flowing partly together with the refrigerant vapor and the supercooled refrigerant from the refrigerant line 17 exchange heat. In this way, an air-cooled absorber is realized by the sensible heat of the liquid refrigerant and the cooling air.

The dilute solution absorbed by the solution pump 10 is preheated by the solution heat exchanger 7 from the dilute solution line 36, and is divided into streams and enters the low temperature regenerator 3 from the dilute solution line 38.
Further, the remaining dilute solution is preheated by the solution heat exchanger 7 and flows into the high temperature regenerator 2 from the dilute solution line 39.

On the other hand, the concentrated solution from the high-temperature regenerator 2 enters the solution heat exchanger 7 from the concentrated solution line 40, cools itself while heating the dilute solution, and passes from the low-temperature regenerator 3 through the concentrated solution line 42 for solution heat exchange. It merges with the concentrated solution that has flowed into the middle part of the vessel 7, further heats the dilute solution, and then flows into the absorber 6 from the concentrated solution line 31.

Next, another embodiment of the present invention will be explained with reference to FIG. Only the parts of the invention that are different from the embodiment shown in FIG. 1 will be described.

The supercooled refrigerant that has exited the condenser 4 is transferred to the refrigerant line 17.
During the process, the pressure is reduced through the pressure reducer 72, and a portion of the liquid refrigerant evaporates. Due to the heat of vaporization,
The temperature of the liquid refrigerant decreases, and in that state it enters the second absorber. There, it exchanges heat with the dilute solution leaving the absorber 6 or partially flowing with the refrigerant vapor, joins the refrigerant line 26 from the refrigerant line 71, and flows into the evaporator 5 from the refrigerant line 21. In the second absorber 62, the dilute solution is further cooled to a solution with even lower lithium bromide concentration, while at the same time promoting the absorption action. The dilute solution produced here has a sufficiently low lithium bromide concentration, making it possible to create a water cooler with an air-cooled absorber.

Next, another embodiment of the invention will be described with reference to FIG. Only the parts of the invention that are different from the embodiments shown in FIGS. 1 and 2 will be described.

The liquid refrigerant containing some vapor that has exited the second absorber 62 enters the gas-liquid separator 74 through the refrigerant line 71.
Separates into vapor and liquid refrigerant. The separated liquid refrigerant is
The refrigerant line 76 joins the refrigerant line 26 . On the other hand, refrigerant vapor flows into the upper part of the absorber 6 from the refrigerant line 75. In this way, the refrigerant vapor flows directly to the absorber without passing through the evaporator, and only the liquid refrigerant is supplied to the evaporator, thereby stabilizing the flow of the liquid refrigerant system and making the liquid refrigerant system more compact.

Next, according to FIG. 4, the refrigeration cycle of the present invention is
A comparison with the conventional one will be explained using a temperature-pressure diagram.

Point E on the refrigerant is the evaporation temperature T _E , and the concentrated solution 31 on the isobaric line with point E absorbs the refrigerant and becomes a dilute solution 36 . The absorption temperature T _A at this time is equal to the condensation temperature T _C. Therefore, the low temperature regenerator temperature is T _LO , point 42
A is at equal pressure with point 17 of the refrigerant. The liquid refrigerant for heating the low temperature regenerator is at point 16A, and the high temperature regenerator temperature is
T _HG , the concentrated solution leaving there will be at point 40A. The above is the conventional refrigeration cycle.

On the other hand, in the refrigeration cycle of the present invention, the high temperature regenerator temperature is raised to t _HG . Therefore, the concentrated solution leaving there is at point 40, and the liquid refrigerant for heating the low temperature regenerator is at point 1.
6, so that the low temperature regenerator temperature is T _LG and the concentrated solution leaving it is at point 42, so the condensation temperature is
t _C , it becomes point C.

Here, since the condenser outlet temperature is T _C and point 17 remains unchanged, in the cycle of the present invention, the refrigerant is supercooled from t _C - T _C , that is, point C to 17. In this way, in the cycle of the present invention, the degree of subcooling of the liquid refrigerant can be very large, so this liquid refrigerant is used to cool the second absorber, thereby realizing an air-cooled absorber.

〔Effect of the invention〕

As described above, according to the present invention, an air-cooled absorption type water chiller/heater can be produced, which has the following effects.

1 No cooling water is required, so there are no restrictions on securing water.

2 No need for cooling water system equipment such as cooling towers or pumps.

3 Easy installation as no cooling water piping work is required.

4. Problems such as cooling water freezing, water leakage, and corrosion are eliminated, and reliability and durability are improved.

[Brief explanation of the drawing]

FIG. 1 shows an example of the present invention, FIG. 2 shows another example of the invention, FIG. 3 shows another example, and FIG. 4 shows a conventional example and a cycle of the present invention in a water-lithium bromide system. Temperature-pressure diagram. 1... absorption type water chiller/heater body, 2... high temperature regenerator, 3... low temperature regenerator, 4... condenser, 5... evaporator, 6... absorber, 7... solution heat exchanger, 9...
... Burner, 10 ... Solution pump, 12 ... Refrigerant pump, 13 ... Refrigerant line, 14 ... Heating tube, 1
5, 16, 17... Refrigerant line, 18... Fan, 19, 20... Fan, 21... Refrigerant line, 22... Cold water pipe, 23... Spreader, 24...
Refrigerant reservoir, 25, 26... Refrigerant line, 27...
Evaporator shell, 28...Vertical pipe, 29...Fin, 30...Scatterer, 31...Concentrated solution line, 3
2...Duct, 33...Intake port, 34...Air path,
35... Slit, 36, 38, 39... Dilute solution line, 40, 42... Concentrated solution line, 48...
Refrigerant flow path, 49... Outlet, 62... Second absorber, 71... Refrigerant line, 72... Pressure reducer, 73
... Refrigerant line, 74 ... Gas-liquid separator, 75 ...
Refrigerant line, 76...Refrigerant line, _tHG , _THG ...
High temperature regenerator temperature, t _LG , T _LG ...Low temperature regenerator temperature,
t _C , T _C ... Condensation temperature, T _A ... Absorption temperature, T _E ...
Evaporator temperature.

Claims (1)

[Claims] 1. High temperature regenerator, low temperature regenerator, condenser, evaporator,
In an absorption water chiller consisting of an absorber, the condenser and absorber are cooled with air, the high temperature regenerator temperature is increased to increase the degree of supercooling of the refrigerant in the condenser, and the solution or An absorption water chiller characterized in that a solution containing refrigerant vapor is cooled with the supercooled refrigerant. 2. An absorption type water cooler according to claim 1, characterized in that the high temperature regenerator is made of a corrosion-resistant material such as a corrosion-resistant metal or ceramic. 3. The absorption water chiller according to claim 1, characterized in that a pressure reducer is provided between the condenser and the cooler for the solution exiting the absorber or the solution in which refrigerant vapor is mixed. Absorption water cooler. 4. In the absorption water chiller according to claim 3, a gas-liquid separator is provided in the liquid refrigerant line at the outlet of the cooler for the solution exiting the absorber or the solution mixed with refrigerant vapor, and the gas-liquid separator An absorption type water chiller characterized by guiding the liquid refrigerant separated in the container to the evaporator and the refrigerant vapor to the absorber.