JPS5815702B2 - Water ↓ - Lithium salt absorption refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water-lithium salt-based absorption refrigerator, which makes it possible to cool the absorbed heat of an absorption solution through heat exchange with air, and is useful in areas with high temperatures and poor water resources. The present invention relates to a water-lithium salt absorption refrigerator which can also be used in.

In conventional water-lithium salt absorption refrigerators, in order to obtain the desired evaporation temperature, it is necessary to set the temperature of the absorption solution to a temperature that exhibits a pressure equal to the vapor pressure of water at the evaporation temperature. is necessary.

For example, in order to obtain an evaporation temperature of about 5°C, if the concentration of the absorption solution is normal, it is necessary to cool it to about 40°C, which usually requires cooling water of about 32°C.

On the other hand, if you want to obtain the same evaporation temperature as above when the cooling water temperature is high, you can increase the concentration of the absorption solution, but increasing the concentration may cause crystallization, so this is not recommended. There are limits to this, and in practice it has been impossible to increase the concentration of the absorption solution beyond the current level.

Therefore, if you try to use a conventional water-lithium salt absorption refrigerator, for example in a desert region with high temperatures and poor water resources, and try to cool the absorption solution directly or indirectly using sensible heat changes in the air, However, since the temperature difference between the absorption temperature and the outside air temperature is small, the heat transfer area required for cooling is extremely large, making it unsuitable for practical use.

The present invention eliminates the above-mentioned shortcomings and improves the temperature when the temperature is high.
The purpose of this invention is to provide a water-lithium salt absorption refrigerator that can employ an air cooling method so that it can be used even in regions with poor water resources.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a system diagram showing an embodiment of a water-lithium salt absorption refrigerator according to the present invention, in which 1 is a high-pressure regenerator, 2 is a low-pressure regenerator, and 3 is a system diagram that uses steam from the high-pressure regenerator 1. , which is a heating coil for heating the low-pressure regenerator 2.

4 is a condenser, 5 is a condenser coil, 6 is an evaporator coil, 7
is the absorber coil, 8 is the evaporator coil 6 and absorber coil 7
This is a heat exchanger that should be a feature of the present invention and is placed in the middle of the

9 is a heat exchanger for exchanging heat between the concentrated solution from the low-pressure regenerator 2 and the dilute solution from the absorption chamber consisting of the evaporator coil 6, absorber coil 7, heat exchanger 8, etc. vessel, 10
is a heat exchanger for exchanging heat between the concentrated solution from the high-pressure regenerator 1 and the dilute solution from the heat exchanger 9.

11 is a pipe for guiding the refrigerant from the condenser 4 to the heat exchanger 8 and the evaporator coil 6; 12 is a pipe for guiding the concentrated solution from the heat exchanger 9 to the heat exchanger 8 and the absorber coil 7; It is a road.

13 is a heating source for heating the high-pressure regenerator 1; 14 is a radiator for cooling cooling water by heat exchange with air;
15 is a tank fan that sends air to the radiator 14; 16 is a cooling load; 17 is a circulation pump that sends the dilute solution to the high-pressure regenerator 1; 18 is a tank pipe that leads the dilute solution to the circulation pump 17; 19 A pump 20 circulates cooling water between the condenser coil 5 and the radiator 14, and a pump 20 circulates cold water between the evaporator coil 6 and the cooling load 16.

Next, the operation of the water-lithium salt absorption refrigerator according to the present invention configured as described above will be explained.
In this step, the lithium salt absorption solution, which has become a dilute solution by absorbing the refrigerant supplied through the heat exchangers 9 and 10, is heated.

Therefore, the refrigerant in the absorption solution is evaporated, the absorption solution has an intermediate concentration, and the absorption solution is introduced into the low pressure regenerator 2 through the heat exchanger 10 at a low temperature.

In this low-pressure regenerator 2, the introduced absorption solution is further heated and concentrated by the steam from the high-pressure regenerator 1, and becomes a concentrated solution.

After this concentrated solution passes through the heat exchanger 9 and is cooled to a low temperature, it is evenly distributed to the absorber coil 7 and the evaporator coil 6 side of the heat exchanger 8.

On the other hand, high-temperature, high-pressure refrigerant vapor generated in the high-pressure regenerator 1 is supplied to the condenser 4 via the heating coil 3 of the low-pressure regenerator 2, where it is cooled by the surrounding absorption solution. It becomes a liquid refrigerant and flows into the condenser 4 due to the pressure difference.

Furthermore, low-pressure refrigerant vapor generated by heating by the heating coil 3 in the low-pressure regenerator 2 is supplied to the condenser 4, cooled and condensed by the condenser coil 5, and becomes liquid refrigerant.

This liquid refrigerant, together with the liquid refrigerant flowing from the heating coil 3, passes through the pipe line 11 and is evenly distributed to the evaporator coil 6 and the absorber coil 7 side of the heat exchanger 8.

The heat exchanger 8 will be sprayed with concentrated solution on one side (evaporator coil side 6) and refrigerant on the other side (absorber coil side 7).

Therefore, the refrigerant is heated by the concentrated solution sprayed on the opposite surface, evaporates, and is absorbed by the concentrated solution sprayed onto the absorption coil 7.

On the other hand, the concentrated solution sprayed on the heat exchanger 8 will be cooled by the refrigerant sprayed on the opposite side.

Therefore, the pressure in the room where the evaporator coil 6 is present is low,
The refrigerant spread on the evaporator coil 6 takes heat from the cold water flowing inside the evaporator coil 6 and evaporates, and this refrigerant vapor is absorbed by the concentrated solution spread on the heat exchanger 8.

In this way, the concentrated solution sprayed on the absorber coil 7 and the heat exchanger 8 absorbs the refrigerant vapor sprayed and evaporated on the evaporator coil 6 and the heat exchanger 8, and becomes a dilute solution. It is pumped through line 18 by solution circulation pump 17 to heat exchanger 9 - heat exchanger 10 - high pressure regenerator 1 .

Thereafter, similar operations are repeated to cool the cooling load 16 to a desired temperature.

Incidentally, the above-mentioned changes related to absorption and evaporation will be supplementally explained with reference to FIG.

The absorption solution sprayed on the absorber coil 7 is a concentrated solution with a concentration ε3, which is cooled from the state of point F to point G, and absorbs the refrigerant vapor shown at point L that has been evaporated by the heat exchanger 8.

Therefore, the absorption solution becomes a dilute solution with a concentration ε, and is sent to the heat exchanger 9 in a five-point state.

On the other hand, since the liquid refrigerant sprayed in the heat exchanger 8 evaporates at a temperature T1°C indicated by point L, the temperature of the concentrated solution on the opposite side can also be assumed to be 10°C.

That is, the concentrated solution ε3 sprayed on the heat exchanger 8 changes from the F point to the H point and then to the 1 point.

During this time, heat is taken from the cold water flowing in the evaporator coil 6, and the refrigerant vapor is evaporated by cooling it (M point state)
becomes a dilute solution with a concentration ε.

In the conventional water-lithium salt type absorption refrigerator, the evaporation temperature T of the refrigerant evaporated in the evaporator coil 6.

In order to obtain this, it was necessary to cool the vapor pressure at point M, that is, the pressure of Po, to the temperature T0 exhibited by the solution with concentration ε, and a large-scale cooling means had to be installed for this purpose. .

However, according to the present invention described above, it is only necessary to cool the vapor pressure at point L, that is, the pressure of P2, to the temperature indicated by the solution of concentration ε, and the range to be cooled does not need to be extremely narrow, so that the cooling means is not required. Something extremely simple would be fine.

Incidentally, assuming that the solution concentration ε is 58% and ε3 is 62%,
Evaporation temperature T.

= 5°C, with the conventional model T1 = 38°C
Therefore, in the case of the present invention, T2=77°C, which means that the absorption solution cooling temperature of the present invention is about 40°C higher than that of the conventional case.

As described above, according to the present invention, it is possible to provide a water-lithium salt type absorption refrigerator which can obtain a sufficient power effect even when the absorption heat of the absorption solution is cooled by heat exchange with air. The present invention is not limited to the above-mentioned embodiment, and can be modified in various ways without departing from the scope of the invention.

For example, in FIG. 2, the evaporator coil 6 and the heat exchanger 8 are first sprayed with refrigerant and absorption solution, and then the refrigerant and absorption solution are flowed to the opposite side of the heat exchanger 8 and the absorber coil 7. An example is shown.

Reference numerals 21 and 22 denote circulation pumps, and the other parts are the same as those in FIG. 1, so the same parts are given the same reference numerals and detailed explanation will be omitted.

Fig. 3 shows an embodiment in which the heat generated by condensation and absorption is directly cooled by air, where 5 is a condensing cooler, 7 is an absorption cooler, and 15 is a blower fan. The other parts are the same as those in FIG. 1, and the same parts are denoted by the same reference numerals and detailed explanation will be omitted.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing one embodiment of a water-lithium salt absorption refrigerator according to the present invention, FIGS. 2 and 3 are system diagrams showing other embodiments of the present invention, and FIG. FIG. 3 is an operation cycle diagram of water-lithium salt absorption refrigeration according to the present invention. 1... High pressure regenerator, 2... Low pressure regenerator, 4... Condenser, 6... Evaporator coil, 7... Absorber coil,
8... Heat exchanger, 9.10... Heat exchanger, 13...
-Heat source, 14...Radiator, 16...Cooling load.

Claims (1)

[Claims] 1. Liquid refrigerant is sprayed on the evaporator coil and evaporated, and the evaporated refrigerant is absorbed into the absorption solution sprayed on the absorber coil, and the dilute absorption solution that has absorbed this refrigerant is heated in a regenerator to become a refrigerant. In a water-lithium salt absorption refrigerator having a circulation path for separating into a concentrated absorption solution and a concentrated absorption solution, a part of the absorption solution is sprinkled on the evaporator coil side between the evaporator coil and the absorber coil. A water-lithium salt absorption refrigerating machine, further comprising a heat exchanger disposed on the absorber coil side to which a portion of the liquid refrigerant is sprayed.