JP2000171119A - Triple-effect absorption refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a triple-effect absorption refrigerating machine which enlarges the heat recovery from a heat source and lowers the temperature and pressure of a high-temperature regenerator. SOLUTION: In a triple-effect absorption refrigerating machine which has a high- temperature regenerator 4, a middle-temperature regenerator 5, a low-temperature regenerator 6, a condenser 3, and an evaporator 1 for its main components, the middle- temperature regenerator 5 is composed of the two of the middle-temperature regenerator 5 heated with the refrigerant vapor from the high-temperature regenerator and the middle-temperature regenerator 10 heated with an external heat source after heating of the high-temperature regenerator, and it will do to so connect the solution pipe of the middle-temperature regenerator as to lead it from the middle-temperature regenerator 5 to the middle-temperature regenerator 10, and also the high-temperature regenerator 4 and the middle-temperature regenerator 5 are divided into plural stages, and solution is let flow in series severally to the high-temperature regenerator 4 and the middle-temperature regenerator 5 divided in plural stages, and also the refrigerant vapor from the high-temperature regenerator on the stage in lowest concentration is connected to the heating side of the middle-temperature regenerator on the stage in highest concentration, and likewise they are connected to be thinner in order or connected to be thicker in order.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption refrigerator, and more particularly to a triple effect absorption refrigerator having high thermal efficiency and being characterized by an economical high and medium temperature regenerator.

[0002]

2. Description of the Related Art For an absorption refrigerator using water as a refrigerant or water as a main component and an aqueous salt solution as an absorbent, a high-temperature regenerator, a medium-temperature regenerator, a low-temperature regenerator, a condenser,
In triple-effect absorption refrigerators, which consist mainly of absorbers, evaporators and heat exchangers, the temperature of the solution in the high-temperature regenerator is high, and the temperature of the heating source at the outlet of the high-temperature regenerator rises accordingly. Heat recovery tends to be insufficient. In addition, since the pressure and temperature of the high-temperature regenerator are kept low, the concentration of the low-temperature regenerator or medium-temperature regenerator cannot be increased, and the concentration range tends to be small. It tends to decrease. Furthermore, although there are various types of triple effect absorption refrigerators, the internal pressure of the high-temperature regenerator (saturation temperature of the solution) and the temperature of the solution tend to be high regardless of which cycle is used. There was a problem or corrosion due to high temperature.

[0003]

SUMMARY OF THE INVENTION Accordingly, in view of the above-mentioned prior art, the present invention increases the heat recovery from a heating source and reduces the pressure and temperature in a high-temperature regenerator even slightly to reduce the strength. Another object of the present invention is to provide a triple-effect absorption refrigerator with high efficiency by reducing the problem of corrosion due to high temperature and increasing the concentration range of the absorber.

[0004]

In order to solve the above-mentioned problems, the present invention comprises a high-temperature regenerator, a medium-temperature regenerator, a low-temperature regenerator, a condenser, an absorber, an evaporator and a heat exchanger. In a triple effect absorption refrigerator connected with a solution pipe and a refrigerant pipe, the intermediate temperature regenerator is heated with refrigerant vapor from the high temperature regenerator, and the external heating after heating the high temperature regenerator. It consists of two medium temperature regenerators that heat using a source. In the absorption refrigerator, the solution pipe of the intermediate temperature regenerator is a solution concentrated in the intermediate temperature regenerator heated by the refrigerant vapor from the high temperature regenerator,
The connection is preferably made to lead to a medium temperature regenerator that is heated using an external heating source from a high temperature regenerator.

In the present invention, a high-temperature regenerator, a medium-temperature regenerator, a low-temperature regenerator, a condenser, an absorber, an evaporator, and a heat exchanger are used as main components, and these are connected by a solution pipe and a refrigerant pipe. In the triple-effect absorption refrigerator, while the high-temperature regenerator and the medium-temperature regenerator are divided into a plurality of stages and a plurality of stages of high-temperature regenerators and medium-temperature regenerators, each of which flows the solution in series,
Connect the refrigerant vapor from the high-temperature regenerator with the lowest concentration to the heating side of the medium-temperature regenerator with the lowest concentration, then regenerate the refrigerant vapor from the high-temperature regenerator with the lowest concentration, and then regenerate the medium-temperature with the denser stage Connected to the heating side of the regenerator, and similarly, the refrigerant vapor from the high-temperature regenerator is sequentially connected to the heating side of the medium-temperature regenerator, and the refrigerant vapor from the high-temperature regenerator with the highest concentration is diluted with the least concentration. It is to be connected to the middle temperature regenerator of the stage.

In the absorption refrigerator, two-stage high-temperature regenerators and intermediate-stage regenerators are provided, each having two stages. Refrigerant vapor from the high-temperature regenerator with the lower concentration is used to separate the refrigerant vapor from the higher-density stage. Connected to the heating side of the medium-temperature regenerator, and the refrigerant vapor from the high-temperature regenerator in the higher concentration stage can be connected to the heating side of the medium-temperature regenerator in the lower concentration stage,
Further, the intermediate-temperature regenerator can be provided with an intermediate-temperature regenerator that uses an external heating source that heats the high-temperature regenerator. In this case, a two-stage intermediate-temperature regenerator that is heated by refrigerant vapor from the high-temperature regenerator A solution pipe can be connected so that the solution concentrated in the vessel is guided to a medium-temperature regenerator for heating using an external heating source. Further, in the triple effect absorption refrigerator of the present invention described above, the absorber and the evaporator are each divided into two stages, a low stage and a high stage. A pair is provided in an independent shell, and the concentrated solution is first guided to the low-stage absorber, then to the high-stage absorber, and the cold water is first guided to the high-stage evaporator, and then to the low-stage evaporator. Each piping path can be configured.

[0007]

Next, the present invention will be described in detail. By adding a medium-temperature regenerator heated by an external heat source in the present invention, heat recovery of the external heat source can be performed by a medium-temperature regenerator having a lower boiling temperature than a high-temperature regenerator, and the amount of heat recovery increases. In addition, the concentrated solution from the intermediate temperature regenerator heated and concentrated by the refrigerant vapor or the concentrated solution from the intermediate temperature regenerator heated and concentrated by the high temperature regenerator or the concentrated solution concentrated by the high temperature regenerator is further concentrated by the recovered heat. The concentration returning to the absorber rises, the concentration width in the absorber is increased, and the capacity of the absorber can be fully utilized.

Further, the high-temperature regenerator and the intermediate-temperature regenerator are divided into a plurality of stages, and the refrigerant vapor from the low-density high-temperature regenerator is connected to the heating side of the medium-density regenerator with the highest concentration, and the solution is formed into a series. By successively flowing and concentrating, the difference in boiling temperature (evaporation temperature) due to the difference in concentration in the medium-temperature regenerator is used to increase the boiling pressure in the high-concentration region in the high-temperature regenerator, It is intended to lower the boiling temperature in the high concentration region by lowering the pressure than the boiling pressure.
According to the present invention, the refrigerant vapor in the high-concentration region in the high-temperature regenerator is guided to the heat transfer section in the low-concentration region of the medium-temperature regenerator, so that the boiling temperature in the high-temperature region of the high-temperature regenerator can be reduced. In particular, in a cycle in which a dilute solution is led to a low-temperature regenerator and a medium-temperature regenerator, the boiling temperature of the solution in the low-temperature and medium-temperature regenerators can be reduced, and the boiling temperature can be further reduced. .

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic process diagram showing an example of the absorption refrigerator of the present invention. In FIG. 1, 1 is an evaporator, 2 is an absorber, 3 is a condenser, 4 is a high temperature regenerator, 5 is a medium temperature regenerator, 6 is a low temperature regenerator, 7 is a low temperature heat exchanger, and 8 is a medium temperature heat exchanger. , 9 is a high-temperature heat exchanger, 10 is an external heat source medium temperature regenerator,
12 is a regenerator pump, 13 is a solution pump, 14 is a refrigerant pump, 15 is an external heat source, 16 and 17 are cooling water, 18 is cold water, 20 to 26 are solution pipes, and 27 to 30 are refrigerant pipes.

The operation of FIG. 1 will be described.
From the low-temperature heat exchanger 7 by the solution pump 13.
And then heat exchange with the concentrated solution on the heating side to increase the temperature. After leaving the low-temperature heat exchanger 7, a part of the diluted solution is guided to the low-temperature regenerator 6, and the remaining diluted solution is The solution is led to the intermediate temperature regenerator 5 through the intermediate temperature heat exchanger 8 by the pipe 22 and is supplied to the intermediate temperature regenerator 5.
A part of the concentrated solution concentrated in the high-temperature heat exchanger 9
Is introduced into the high-temperature regenerator 4 through the heated side, and is heated and concentrated by the external heat source 15 to become a concentrated solution.
Through the heating side of the high-temperature heat exchanger 9 and the remainder of the concentrated solution concentrated in the intermediate-temperature regenerator 5 to the intermediate-temperature regenerator 10 heated by an external heat source. The solution is supplied to the medium temperature regenerator 10
Then, by the external heat source 15 that has passed through the high-temperature regenerator 4,
After being heated and concentrated, it passes through the heating side of the intermediate-temperature heat exchanger 8,
The concentrated solution from the low-temperature regenerator 6 is led to the heating side of the low-temperature heat exchanger 7. The concentrated solution that enters the heating side of the low-temperature heat exchanger 7 heats the dilute solution on the heated side, and cools itself,
After leaving the low-temperature heat exchanger 7, it enters the absorber 2.

In the high-temperature regenerator 4, the refrigerant vapor heated by the external heat source 5 and generated from the solution is led from the pipe 27 to the heating side of the medium-temperature regenerator 5, and heats the dilute solution introduced into the medium-temperature regenerator 5. Concentrate. The refrigerant vapor generated in the intermediate-temperature regenerator 5 is guided to the heating side of the low-temperature regenerator 6 through the pipe 28 together with the refrigerant vapor from the intermediate-temperature regenerator 10 heated by an external heat source, and the heated side of the low-temperature heat exchanger 8 is heated. The dilute solution led via is concentrated by heating, and the refrigerant vapor after heating is condensed and led to the condenser 3. The refrigerant vapor generated in the low-temperature regenerator 6 is guided to the condenser 3 and is cooled and condensed by the cooling water 17. The refrigerant in the condenser 3 is guided from the pipe 29 to the evaporator 1, where the refrigerant takes heat from the cold water 18 to exhibit a refrigeration effect and evaporates. The evaporated refrigerant vapor is absorbed by the solution in the absorber 2. The heat of absorption at the time of absorption is cooled by cooling water 16 flowing through the absorber. The refrigerant that does not evaporate is transferred to the pipe 3 by the refrigerant pump 14.
The dilute solution having absorbed the refrigerant is circulated through the heat exchanger by the solution pump 13.
When guided from the intermediate-temperature regenerator 5 to the high-temperature regenerator 4, it is preferentially guided to the regenerator pump 12 side, and the rest overflows and is guided to the intermediate-temperature regenerator 10 heated by an external heat source.

FIG. 2 is a schematic process diagram showing another example of the triple effect absorption refrigerator of the present invention, and all the reference numerals in FIG. 2 have the same meaning as in FIG. In FIG. 2, the difference from FIG. 1 is that the dilute solution from the absorber 2 passes through the heated side of the low-temperature heat exchanger 7, the medium-temperature heat exchanger 8, and the high-temperature heat exchanger 9 in FIG. 2. Later, the branched solution is configured so that a part thereof is introduced into the low-temperature regenerator 6, the medium-temperature regenerator 5, and the high-temperature regenerator 4, respectively. Along with the concentrated solution from the regenerator 4, the whole amount is introduced into a medium temperature regenerator 10 which is heated by an external heat source. Even with such a configuration, the same operation as in FIG. 1 can be obtained.

FIG. 3 (a) is a schematic process diagram showing another example of the absorption refrigerator of the present invention, and FIG. 3 (b) is a partially enlarged view showing two stages of an absorber and an evaporator. 3 also have the same meaning as in FIG. In FIG. 3, the dilute solution from the absorber 2 is introduced into the heated side of the low-temperature heat exchanger 7 by the solution pump 13 and exchanges heat with the concentrated solution on the heated side to increase the temperature. After exiting, it branches and guides a part of the dilute solution to the low-temperature regenerator 6, leads the remaining dilute solution to the medium-temperature regenerator 5 via the medium-temperature heat exchanger 8 through the pipe 22, and concentrates the medium at the medium-temperature regenerator 5. A part of the concentrated solution is introduced into the high-temperature regenerator 4a via the heated side of the high-temperature heat exchanger 9 via the pipe 23 and concentrated, and then the solution further concentrated in the high-temperature regenerator 4b is The pipe 24 passes through the heating side of the high-temperature heat exchanger 9, and is guided to the heating side of the medium-temperature heat exchanger 8 together with the remainder of the concentrated solution concentrated in the intermediate-temperature regenerator 5. Together with the concentrated solution from the above to the heating side of the low-temperature heat exchanger 7. The concentrated solution entering the heating side of the low-temperature heat exchanger 7 heats the dilute solution on the heated side, cools itself, exits the low-temperature heat exchanger 7 and enters the absorber 2.

In the high-temperature regenerator 4, the solution is heated by the external heat source 15, and the solution is sequentially concentrated in the order of 4 a and 4 b.
The refrigerant vapor from 4a is guided to the high concentration side heating section 5b of the intermediate temperature regenerator 5, and the dilute solution introduced into the intermediate temperature regenerator 5 is supplied to the low concentration side heating section 5a. It is heated and concentrated in order. The refrigerant vapor from the high-temperature regenerator 4 is condensed after being heated and guided to the heating side (or the condenser 3) of the low-temperature regenerator 6. The refrigerant vapor generated in the intermediate-temperature regenerator 5 is guided to the heating side of the low-temperature regenerator 6 by a pipe 28, and the diluted solution guided through the heated side of the low-temperature heat exchanger 8 is heated and concentrated. Refrigerant vapor is condensed and led to the condenser 3. The refrigerant vapor generated in the low-temperature regenerator 6 is guided to the condenser 3 and is cooled and condensed by the cooling water 17.

The refrigerant in the condenser 3 is led to the evaporator 1 through a pipe 29, where the refrigerant takes heat from the cold water 18 to exhibit a refrigerating effect and evaporates. The evaporated refrigerant vapor is absorbed by the solution in the absorber 2. The heat of absorption at the time of absorption is cooled by cooling water 16 flowing through the absorber. The refrigerant that does not evaporate is circulated to the evaporator 1 through the pipe 30 by the refrigerant pump 14, and the dilute solution that has absorbed the refrigerant is circulated through the heat exchanger by the wave pump 13. When the heat is guided from the intermediate temperature regenerator 5 to the high temperature regenerator 4, it is preferentially guided to the regenerator pump 12 side, and the rest overflows and is guided to the heating side of the intermediate temperature heat exchanger 8.

FIG. 4 is a schematic process diagram showing another example of the absorption refrigerator of the present invention. In FIG. 4, the dilute solution from the absorber 2 is supplied with a low-temperature heat exchanger 7, a medium-temperature heat exchanger 8, After passing through the heated side of the high-temperature heat exchanger 9, it is branched and partly introduced into the low-temperature regenerator 6, the medium-temperature regenerator 5, and the high-temperature regenerator 4, respectively. The difference from FIG. 3 is that the concentrated solution from the regenerator 5 is introduced together with the concentrated solution from the high-temperature regenerator 4 into the heating side of the medium-temperature heat exchanger. FIG. 5 is also a schematic process diagram showing another example of the absorption refrigerator of the present invention, and is different from FIG. 3 only in that an intermediate temperature regenerator 10 for heating with an external heat source 15 is provided. I have. FIG. 6 shows a solution cycle diagram applicable to the triple effect absorption refrigerator of the present invention. In FIG. 6, (a) series flow, (b) branch flow, (c) parallel flow, (d)
It is a repurse flow, and other combinations thereof can be applied, and the boiling temperature can be reduced no matter which cycle is used.

Next, cold water conditions: inlet 13 ° C., outlet 7 ° C.
Let us compare the cycle examples when the cooling water inlet is at 31 ° C.
(Water is used as the refrigerant and LiBr aqueous solution is used as the absorbent.) When only one pair of the high-temperature regenerator and the medium-temperature regenerator is used, the evaporation temperature of the evaporator is 5.5 ° C., and the solution outlet temperature of the absorber is 36.0. C, Dilute solution concentration 55.5 wt% Condensation temperature 37.0 C, Low temperature regenerator solution outlet temperature 76.2 C Medium temperature regenerator dew point 80.1 C, Medium temperature regenerator solution outlet temperature 125.4 C High temperature regenerator dew point 129 0.3 ° C., high temperature regenerator solution outlet temperature 186.9 ° C. high temperature regenerator pressure 2.70 kg / cm ² A (1.67 kg / cm ² G)

Flow according to the present invention: FIG. 3 Evaporation temperature of evaporator 5.5 ° C., absorber solution outlet temperature 36.0 ° C., dilute solution concentration 55.5 wt% condensing temperature 37.0 ° C., low temperature regenerator solution outlet Temperature 76.2 ° C Medium temperature regenerator dew point 80.1 ° C, Medium temperature regenerator solution intermediate temperature 123.4 ° C 80.1 ° C, Medium temperature regenerator solution outlet temperature 125.4 ° C High temperature regenerator dew point (a) 129.3 ° C High temperature regenerator solution intermediate temperature 184.5 ° C High temperature regenerator dew point (b) 127.3 ° C High temperature regenerator solution outlet temperature 184.5 ° C High temperature regenerator pressure 2.70 kg / cm ² A (1.67 kg / cm) the ² G) the present invention, the pressure is substantially equal, to a temperature advantageous.

Further, as shown in FIG. 3 (b), in the absorption refrigerator, the absorber and the evaporator are each divided into two stages of a low stage 2 ', 1' and a high stage 2 ", 1". Then, each of these divided single absorbers and evaporators is provided as a pair in an independent shell, and the concentrated solution is first guided to the low-stage absorber 2 ′, and then the high-stage absorber 2 ″ If the boiling point in each of the low-temperature and medium-temperature regenerators is further reduced by diluting the concentration of the dilute solution in such a manner as described above, the pressure and temperature of the high-temperature regenerator can be reduced, and further effects can be obtained.

[0020]

According to the present invention, by adding a medium-temperature regenerator for heating with an external heat source, the heat recovery of the external heat source can be sufficiently performed, the thermal efficiency can be improved, and the temperature width between the entrance and exit of the absorber can be widened. Since the capacity of the refrigerator can be sufficiently utilized, the capacity of the refrigerator can be sufficiently exhibited. In addition, the high-temperature regenerator and the medium-temperature regenerator are divided into a plurality of stages, and by flowing the solution in series, the pressure and temperature of the high-temperature generator can be reduced, and the corrosive environment is alleviated.
In addition, pressure problems can be alleviated, and materials such as mild steel which has been conventionally used for double effects can be used.

[Brief description of the drawings]

FIG. 1 is a schematic process diagram showing an example of an absorption refrigerator of the present invention.

FIG. 2 is a schematic process diagram showing another example of the absorption refrigerator of the present invention.

FIG. 3A is a schematic process diagram illustrating another example of the absorption refrigerator of the present invention, and FIG. 3B is a partial configuration diagram illustrating another example of the absorber and the evaporator.

FIG. 4 is a schematic process diagram showing another example of the absorption refrigerator of the present invention.

FIG. 5 is a schematic process diagram showing another example of the absorption refrigerator of the present invention.

FIG. 6 is a solution cycle diagram to which the triple effect absorption refrigerator of the present invention can be applied.

[Explanation of symbols]

1, 1 ′, 1 ″: evaporator, 2, 2 ′, 2 ″, A: absorber, 3: condenser, 4, 4a, 4b, GH: high temperature regenerator, 5, 5a, 5b, GM : Medium temperature regenerator, 6, GL: Low temperature regenerator, 7: Low temperature heat exchanger, 8: Medium temperature heat exchanger, 9:
High-temperature heat exchanger, 10: external heat source intermediate temperature regenerator, 12: regenerator pump, 13: solution pump, 14: refrigerant pump, 1
5: external heat source, 16, 17: cooling water, 18: cold water, 20
~ 26 solution piping, 27 ~ 30: refrigerant piping

Claims (6)

[Claims] 1. A high-temperature regenerator, a medium-temperature regenerator, a low-temperature regenerator,
Condenser, absorber, evaporator, and heat exchangers are the main components, and in a triple effect absorption refrigerator in which these are connected by a solution pipe and a refrigerant pipe, the medium-temperature regenerator uses refrigerant vapor from a high-temperature regenerator. A triple effect absorption refrigerator comprising: an overheated medium-temperature regenerator; and a medium-temperature regenerator that heats the high-temperature regenerator using an external heating source after heating. 2. A solution pipe of the intermediate temperature regenerator is provided with a medium concentrated by a medium temperature regenerator heated by refrigerant vapor from the high temperature regenerator, and a medium temperature heated by an external heating source from the high temperature regenerator. The triple-effect absorption refrigerator according to claim 1, wherein the triple-effect absorption refrigerator is connected so as to be guided to a regenerator. 3. The high-temperature regenerator and the medium-temperature regenerator heated by the refrigerant vapor are each divided into two stages, and the divided two-stage high-temperature regenerator and the two-stage medium-temperature regenerator are each provided with a solution. And the refrigerant vapor from the high-temperature regenerator with the lower concentration is connected to the heating side of the medium-temperature regenerator with the higher concentration, and the refrigerant from the high-temperature regenerator with the higher concentration is connected. 3. The triple effect absorption refrigerator according to claim 1, wherein the steam is connected to a heating side of a medium temperature regenerator having a lower concentration. 4. A high temperature regenerator, a medium temperature regenerator, a low temperature regenerator,
In a triple-effect absorption refrigerator in which a condenser, an absorber, an evaporator, and a heat exchanger are main components and these are connected by a solution pipe and a refrigerant pipe, the high-temperature regenerator and the medium-temperature regenerator are divided into a plurality of stages. Then, the divided multi-stage high-temperature regenerator and medium-temperature regenerator flow the solution in series, and the refrigerant vapor from the low-density stage high-temperature regenerator passes through Connected to the heating side, then the refrigerant vapor from the high-temperature regenerator in the thinner stage, and then connected to the heating side of the medium-temperature regenerator in the deeper stage, and likewise, the refrigerant vapor from the high-temperature regenerator was successively A triple effect absorption refrigerator, wherein the refrigerant vapor from the high-temperature regenerator with the highest concentration is connected to the heating side of the medium-temperature regenerator with the lowest concentration. 5. The multi-stage high-temperature regenerator and the intermediate-temperature regenerator are each constituted by two stages, and the refrigerant vapor from the low-density stage high-temperature regenerator is separated from the high-density stage by the higher-density stage. 5. A medium-temperature regenerator connected to a heating side, wherein refrigerant vapor from a high-density stage high-temperature regenerator is connected to a heating side of a low-concentration stage medium-temperature regenerator. The triple effect absorption refrigerator described. 6. The absorber and the evaporator are each divided into two stages, a low stage and a high stage, and each of the divided single absorber and evaporator is formed as a pair of independent shells. And the concentrated solution is first guided to the low-stage absorber, and then to the high-stage absorber, and the cold water is first guided to the high-stage evaporator and then to the low-stage evaporator. The triple effect absorption refrigerator according to any one of claims 1 to 5, wherein the absorption refrigerator is configured as follows.