JP2012068019A - Absorption refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorption refrigerating machine that prevents supercooling of absorbing liquid in an absorber, to improve energy efficiency without reducing absorption capacity of the absorbing liquid, while preventing reduction in coefficient of performance (COP).SOLUTION: An absorption refrigerating machine 100 comprises an absorbing liquid circulation passage 7 where an absorbing liquid D circulates between an absorber 2 and a regenerator 3, and operates by generating a dilute absorbing solution D1 by absorbing refrigerants in the absorber 2 and generating a concentrated absorbing solution D2 by evaporating the refrigerants in the regenerator 3. The absorption refrigerating machine 100 also comprises, in the absorbing liquid circulation passage 7 located outside the absorber 2, an absorber heat exchanger 5 which cools the concentrated absorbing solution D2 which circulates from the regenerator 3 to the absorber 2 by heat exchange with a cooling medium C introduced from the outside, and a cooling medium flow path 13 configured to circulate the cooling medium C between the absorber heat exchanger 5 and a condenser heat exchanger 4a located in a condenser 4 and to discharge it to the outside.

Description

  The present invention relates to an absorption refrigerator having an absorption liquid in an absorber, more specifically, an evaporator for evaporating a refrigerant liquid, and a refrigerant vapor generated in the evaporator is absorbed into the absorption liquid to generate a diluted absorption liquid. An absorber, a regenerator that heats the dilute absorption liquid generated by the absorber with a heating means to separate and regenerate the refrigerant vapor and the concentrated absorption liquid, and a condenser that liquefies the refrigerant vapor regenerated by the regenerator It relates to an absorption refrigerator.

The absorption refrigerator as described above evaporates the refrigerant liquid in the evaporator, cools the cooling target medium flowing through the heat exchanger in the evaporator with the heat of vaporization caused by this evaporation, and responds to cooling demand such as cooling. can do.
An example of such a conventional absorption refrigerator is Patent Document 1.
In Patent Document 1, as shown in FIG. 3, an evaporator 50 that evaporates water as a refrigerant liquid under a low pressure, and a water vapor generated in the evaporator 50 is absorbed by the absorbing liquid to generate a diluted absorbing liquid. An absorber 51, a regenerator 53 that heats the dilute absorption liquid generated by the absorber 51 by a heating means 52 to separate and regenerate the water vapor and a concentrated absorption liquid, and a condenser 54 that liquefies the water vapor regenerated by the regenerator 53. And an absorption refrigerator 60 configured to circulate the absorbing liquid between the absorber 51 and the regenerator 53 is disclosed.
Accordingly, the absorption liquid circulates between the absorber 51 and the regenerator 53 in a state where the concentration is changed, and the refrigerant is the evaporator 50, the absorber 51, and the regenerator in a state where the phase state is changed. 53, the cycle of advection between the evaporators 54 is repeated.
Here, in the above-described cycle, in the evaporator 50, heat is removed from the cooling target medium flowing through the heat exchanger 55 in the evaporator 50 by heat of vaporization due to evaporation of water vapor, and the cooling heat recovered by the cooling target medium is recovered. In the absorber 51, the concentrated absorption liquid is sprayed in the absorber 51 and the absorbed heat when absorbing water vapor is circulated through the heat exchanger 56. The temperature of the absorbing liquid in the absorber 51 can be prevented from being raised by collecting with the cooling medium and throwing it outside.

JP-A-1-219453

In the conventional absorption refrigerator 60, the temperature of the absorbent in the absorber 51 is maintained at an appropriate temperature necessary for operation by the heat exchanger 56.
However, it has been found that the following phenomenon occurs in such a conventional absorption refrigerator 60.
A relatively low-temperature cooling medium (usually cooling water) flows through the heat exchanger 56 in the absorber 51, and when the concentrated absorbent generated in the regenerator 53 is sprayed on the heat exchanger 56, Is cooled with a cooling medium to take out the heat of absorption generated by absorption and promotes absorption of the refrigerant, but the concentrated absorbent absorbs water vapor to become a rare absorbent, and for some reason this rare absorbent When a large amount of is generated, a part of the heat exchanger 56 may come into contact with the diluted absorbent, and the diluted absorbent may be supercooled at the heat exchange site. The condensation absorption temperature of the refrigerant is generally determined by the temperature of the cooling medium. In such a state, the condensation absorption temperature of the refrigerant becomes higher than the temperature of the cooling medium by the amount of supercooling. The coefficient of performance (COP value) of the machine 60 was to be reduced.

  The present invention has been made paying attention to such points, and its purpose is to improve energy efficiency without reducing the absorption capacity of the absorption liquid by preventing overcooling of the absorption liquid in the absorber. And an absorption refrigerator that can prevent a decrease in the coefficient of performance.

  In order to achieve this object, the first characteristic configuration of the absorption refrigerator according to the present invention includes an evaporator, an absorber, a regenerator, and a condenser, and between the absorber and the regenerator, Absorption refrigeration comprising an absorption liquid circulation path through which absorption liquid circulates, wherein the refrigerant is absorbed in the absorber to generate a diluted absorption liquid, and the refrigerant is evaporated in the regenerator to generate a concentrated absorption liquid. An absorber heat exchanger that cools the concentrated absorbent flowing from the regenerator to the absorber by heat exchange with a cooling medium introduced from the outside, and the absorbent outside the absorber The cooling medium is provided in a circulation path, and the cooling medium is provided with a cooling medium flow path configured to allow the cooling medium to be circulated through the absorber heat exchanger and the condenser heat exchanger in the condenser to be discharged to the outside. .

According to the first characteristic configuration, the heat exchanger for an absorber is disposed outside the absorber and in an absorption liquid circulation path that communicates the absorber and the heat exchanger for the absorber. Heat exchange between the relatively low-temperature cooling medium introduced from the outside of the absorption chiller and the concentrated absorbent flowing through the absorption liquid circulation path to maintain the absorption chiller in good condition it can. Further, since it is not necessary to provide a heat exchanger in the absorber, there is no possibility that the dilute absorbing liquid in the vicinity thereof is supercooled due to the presence of the heat exchanger in the absorber.
Therefore, the increase in the condensation absorption temperature of the extra refrigerant due to the generation of the supercooled portion is not caused, and a decrease in the coefficient of performance (COP value) can be prevented.
Furthermore, by sharing the cooling medium C, it is possible to simplify the configuration of the apparatus and to effectively recover heat and discharge it to the outside.

  According to a second characteristic configuration of the absorption refrigerator according to the present invention, in addition to the first characteristic configuration, the absorption liquid circulation path includes a forward path through which the rare absorbent is circulated from the absorber to the regenerator, and the regeneration. And a return path through which the concentrated absorbent is circulated from the vessel to the absorber, and a part of the rare absorbent flowing through the forward path is used for the absorber in the return path between the forward path and the return path. It is in the point which provided the bypass route introduced directly in the upstream of a heat exchanger.

  According to the second characteristic configuration, a part of the diluted absorption liquid from the absorber flowing through the absorption liquid circulation path is directly returned to the absorber via the absorber heat exchanger without passing through the regenerator. Since a bypass path is provided, a part of the relatively low-temperature diluted absorbent from the absorber is heated in the regenerator and merged with the relatively high-temperature concentrated absorbent to be distributed to the heat exchanger for the absorber. Can sufficiently cool all of the absorption liquid (dilute absorption liquid and concentrated absorption liquid) returning to the absorber to improve the absorption capacity in the absorber, and a part of the relatively low temperature rare absorption liquid Can be prevented from being heated in the regenerator, and energy input into the regenerator can be saved. At this time, if the pump is installed between the absorber and the bypass path in the outward path of the absorption liquid circulation path, the above-described effects can be sufficiently exhibited with a single pump.

Schematic of absorption refrigerator according to an embodiment of the present application Schematic of absorption refrigerator according to the reference form of the present application Schematic diagram of a conventional absorption refrigerator

An embodiment of an absorption refrigerator 100 according to the present invention will be described with reference to the drawings.
As shown in FIG. 1, the absorption refrigerator 100 is a single-effect absorption refrigerator, and receives an evaporator 1 that evaporates refrigerant liquid and refrigerant vapor generated in the evaporator 1 to form a concentrated absorption liquid. Absorber 2 that absorbs and generates a dilute absorbent having a low concentration, regenerator 3 that accepts the dilute absorbent produced by this absorber 2 and regenerates it as a concentrated absorbent having a high concentration, and is produced by this regenerator 3. The condenser 4 accepts the refrigerant vapor, condenses it as a refrigerant liquid and releases the heat to the outside, the heat exchanger 5 for the absorber exchanges heat between the concentrated absorbent and the cooling medium, and the rare absorbent and the concentrated absorbent. Regenerated concentrated absorption liquid heat exchanger 6 for heat exchange, absorption liquid circulation path 7 for circulating the absorption liquid between absorber 2 and regenerator 3, regenerator 3, condenser 4, evaporator 1, absorber 2 Refrigerant flow passage 8 through which the refrigerant flows in order, a heating hand that heats the dilute absorbent and makes it a concentrated absorbent 10, is configured to include a sprayer 11 as a mixing means for mixing with the refrigerant vapor by spraying a concentrated absorption liquid.
The absorption refrigerator 100 is filled with an aqueous lithium bromide solution as an absorption liquid and water as a refrigerant (refrigerant liquid, refrigerant vapor).
The evaporator 1 is provided with an evaporator heat exchanger 1a through which the cooling target medium U flows, the regenerator 3 is provided with heating means 10 through which hot water H flows, and the condenser 4 is cooled. A condenser heat exchanger 4a through which the medium C flows is provided.

  Each apparatus which comprises this absorption refrigerator 100 is demonstrated based on FIG.

  The evaporator 1 is a device that evaporates the water L as the refrigerant liquid, and communicates with the absorber 2 so that the vapor S as the evaporated refrigerant vapor can be introduced into the absorber 2 described later. Further, by evaporating the water vapor S, heat of vaporization is taken from the cooling target medium U flowing through the evaporator heat exchanger 1a, and the cooling target medium U is cooled. The water L is supplied from a condenser 4 described later via a throttle valve T1.

The absorber 2 is a device that absorbs the water vapor S into the concentrated absorbent D2 having a high concentration sent back from the regenerator 3 to be described later to generate the diluted absorbent D1, and the water vapor S generated in the evaporator 1 is generated. It introduces and mixes with the concentrated absorbent D2 sent back from the regenerator 3 described later to absorb the water vapor S to produce the diluted absorbent D1. The absorber 2 can send the diluted absorbent D1 back to the regenerator 3 to be described later, and can absorb the concentrated absorbent D2 generated by the regenerator 3 back to the absorber 2 so that the absorbent liquid circulation path 7 to be described later. Is communicated with the regenerator 3. The absorber 2 is provided with a sprayer 11 as a mixing means for mixing the concentrated absorbent D2 and the water vapor S, and the concentrated absorbent D2 is sprayed in the absorber 2 to be mixed well with the water vapor S. It is configured to be able to.
In addition, in the absorber 2 in this application, the heat exchanger with which the conventionally provided cooling medium C distribute | circulates is not provided.

  The regenerator 3 is a device that heats the rare absorbent D1 with the heating means 10 and separates and regenerates it into the water vapor S and the concentrated absorbent D2, and the rare absorbent D1 generated in the absorber 2 is passed through the pump P. The diluted absorbent D1 is separated and regenerated into a high-concentration and high-temperature concentrated absorbent D2 and a high-temperature steam S by heat exchange with the warm water H flowing through the heating means 10. The regenerator 3 is in communication with each other so that the high-temperature concentrated absorbent D2 can be sent to the absorber 2 while the high-temperature steam S can be sent to the condenser 4 described later.

  The condenser 4 is a device that condenses and liquefies the water vapor S, and communicates with the regenerator 3 so that the water vapor S separated and regenerated by the regenerator 3 can be introduced. The condenser 4 condenses and liquefies the water vapor S by heat exchange with the cooling medium C flowing through the condenser heat exchanger 4a. The condenser 4 is in communication with the evaporator 1 so that the water L produced by being condensed and liquefied can be sent to the evaporator 1 via the throttle valve T1.

  In addition, as shown in FIG. 1, between the evaporator 1, the absorber 2, the regenerator 3, and the condenser 4, the absorption liquid D (diluted absorption liquid D1, concentrated absorption liquid D2), refrigerant (water L, A flow passage is provided through which the water vapor S) can be circulated.

Between the absorber 2 and the regenerator 3, an absorbing liquid circulation path 7 through which the absorbing liquid D can be circulated is formed.
The absorption liquid circulation path 7 circulates the rare absorption liquid D1 from the absorber 2 to the regenerator 3 through the pump P and the regenerated concentrated absorption liquid heat exchanger 6 which will be described later while changing the concentration. The concentrated absorbent D2 regenerated in this manner is circulated to the absorber 2 via the regenerated concentrated absorbent heat exchanger 6, the three-way valve A, the absorber heat exchanger 5, and the throttle valve T2. D1, concentrated absorbent D2) can be circulated between the absorber 2 and the regenerator 3.
Therefore, the absorption liquid circulation path 7 includes an outward path 7a through which the diluted absorbent D1 flows from the absorber 2 to the regenerator 3, and a return path 7b through which the concentrated absorption liquid D2 flows from the regenerator 3 to the absorber 2. Between the forward path 7a and the return path 7b, there is a bypass path 9 capable of directly introducing a part of the diluted absorbent D1 flowing through the forward path 7a to the upstream side of the absorber heat exchanger 5 in the return path 7b. Is provided.
The bypass path 9 includes a part of the relatively low temperature diluted absorbent D1 supplied from the absorber 2 to the regenerator 3 and a relatively high temperature concentrated absorbent D2 supplied from the regenerator 3 to the absorber 2. It is made to merge and to be able to return to the absorber 2 through the absorber heat exchanger 5.

Between the regenerator 3, the condenser 4, the evaporator 1, and the absorber 2, a refrigerant flow path 8 through which refrigerant (water L, water vapor S) can be circulated is provided.
The refrigerant flow passage 8 allows the high-temperature steam S regenerated in the regenerator 3 to flow in the order of the regenerator 3, the condenser 4, the throttle valve T1, the evaporator 1, and the absorber 2 while being accompanied by a phase change. It is configured to be able to. In addition, although the said refrigerant | coolant (water L, water vapor | steam S) also moves from the absorber 2 to the regenerator 3, the inside of the said absorption liquid circulation path 7 with the said absorption liquid in the state absorbed by the absorption liquid D in this case It will be distributed. Therefore, actually, the refrigerant (water L, water vapor S) is circulated between the evaporator 1, the absorber 2, the regenerator 3, and the condenser 4 through the absorbing liquid circulation path 7 and the refrigerant flow path 8. .

  The absorber heat exchanger 5 is constituted by a heat exchanger provided with a heat transfer tube, and is provided between the throttle valve T2 and the three-way valve A in the return path 7b of the absorbing liquid circulation path 7, and is regenerated in the regenerator 3. Heat exchange is performed between the concentrated absorbent D2 and the cooling medium C. The cooling medium C is a fluid supplied from the outside of the absorption refrigeration machine 100. In this embodiment, the cooling medium C is the same fluid as the cooling medium C flowing through the condenser heat exchanger 4a in the condenser 4. ing. By sharing the cooling medium C in this way, the apparatus configuration can be simplified, and heat can be effectively recovered and discharged to the outside. In addition, a cooling medium flow passage 13 configured to be able to introduce the cooling medium C from the outside of the absorption refrigeration machine 100 and discharge the cooling medium C to the outside through the absorber heat exchanger 5 and the condenser heat exchanger 4a is provided. It has been.

  The regenerated concentrated absorbent liquid heat exchanger 6 is composed of a heat exchanger having a heat transfer tube, and a regenerator and a pump P in the forward path 7a of the absorbent circulation path 7 (a branch point between the bypass path 9 and the forward path 7a). 3, provided between the three-way valve A and the regenerator 3 in the return path 7 b, and the rare absorbent D 1 that has absorbed the water vapor S in the absorber 2 and the concentrated absorbent D 2 that has been regenerated in the regenerator 3. And so that heat exchange can be performed.

  The heating means 10 is a device that supplies heat to the diluted absorbent D1 sent from the absorber 2 into the regenerator 3, and evaporates the refrigerant absorbed in the diluted absorbent D1 as water vapor S, thereby absorbing the concentrated absorption. The liquid D2 and the water vapor S can be separated and regenerated. For example, the heat exchanger tube is configured by a heat exchanger that can supply hot water H to heat the diluted absorbent D1.

  The nebulizer 11 is a device capable of spraying the concentrated absorbent D2 in a mist form. The concentrated absorbent D2 regenerated in the regenerator 3 is sprayed in the form of a mist from the upper part of the absorber 2, and the evaporator 1 is sprayed. It is comprised so that it can mix favorably with the water vapor | steam S introduce | transduced from.

The three-way valve A is provided between the regenerated concentrated absorbent liquid heat exchanger 6 and the absorber heat exchanger 5 in the return path 7b of the absorbent circulation path 7, and is sent from the absorber 2 via the bypass path 9. The dilute absorbing liquid D1 and the concentrated absorbing liquid D2 sent from the regenerator 3 can be combined and returned to the absorber 2 through the absorber heat exchanger 5 and the throttle valve T2, while adjusting the flow rate. It is configured as follows.
Therefore, in the absorption liquid circulation path 7, the absorption liquid D is absorbed from the absorber 2 through the pump P, the bypass path 9, the three-way valve A, the absorber heat exchanger 5, and the throttle valve T2 while changing the concentration. A circulation path that can circulate in the vessel 2 is formed.

The throttle valve T <b> 1 is provided between the condenser 4 and the evaporator 1, and is configured to release the pressure of the water L liquefied in the condenser 4 and supply the water L to the evaporator 1.
The throttle valve T <b> 2 is provided between the absorber heat exchanger 5 and the absorber 2 in the return path 7 b of the absorber circulation circuit 7, and reduces the pressure of the concentrated absorbent D <b> 2 brought to a low temperature state by the absorber heat exchanger 5. It is configured to be opened so that the concentrated absorbent D2 can be supplied to the absorber 2.
Accordingly, the pressures of the regenerator 3 and the condenser 4 and the pressures of the evaporator 1 and the absorber 2 can be divided into appropriate operating pressure states by these two throttle valves T1 and T2.

The pump P is provided between the absorber 2 and the regenerated concentrated absorbent heat exchanger 6 (a branch point between the bypass path 9 and the forward path 7a) in the forward path 7a of the absorbent circulation path 7, and the opening degree of the three-way valve A Is adjusted so that the rare absorbent D1 from the absorber 2 is supplied to the regenerator 3 through the regenerated concentrated absorbent heat exchanger 6 and the dilute absorbent D1 is supplied to the absorber 2 through the bypass 9. These supply flow rates can be adjusted, respectively.
Therefore, by adjusting the respective supply flow rates according to the output of the pump P, the regeneration in the regenerator 3, the absorber 2, etc., the absorption speed, etc. are adjusted, and the operating state of the absorption refrigerator 100 is changed. It is possible to realize an optimum operating state.

Next, operation | movement of the absorption refrigerator 100 which concerns on this application is demonstrated based on FIG.
The evaporator 1, the absorber 2, the regenerator 3, and the condenser 4 of the absorption refrigerator 100 of the present application are communicated by the absorbing liquid circulation path 7 and the refrigerant flow path 8 as described above to form a closed system. The closed system operates under conditions maintained under low pressure conditions (several mmHg to several tens mmHg). Specifically, the evaporator 1 and the absorber 2 are in a negative pressure state with substantially the same pressure, and the regenerator 3 and the condenser 4 are in a negative pressure state suitable for operation, respectively, and the throttle valve T1, By T2, the pressures of the evaporator 1 and the absorber 2 are kept lower than the pressures of the regenerator 3 and the condenser 4, and the absorption refrigerator 100 operates.

First, the case where the valve on the bypass path 9 side in the three-way valve A is closed under the above conditions will be described with reference to FIG.
When the water L existing in the evaporator 1 takes heat (cools) from the cooling target medium U flowing through the evaporator heat exchanger 1a in the evaporator 1, the water L evaporates to become water vapor S. It flows through the refrigerant flow passage 8 and moves to the absorber 2 side. At this time, the water vapor S is well mixed with the concentrated absorbent D2 supplied from the regenerator 3 through the throttle valve T2 and sprayed by the sprayer 11, and is efficiently absorbed by the concentrated absorbent D2. The concentrated absorbent D2 absorbs the water vapor S, so that the temperature rises due to the heat of absorption and becomes a rare absorbent D1 in which the concentration of lithium bromide is reduced, and is stored at the bottom of the absorber 2.
The dilute absorbent D1 is sucked by the pump P, flows through the forward path 7a of the absorbent circulation path 7, and is supplied to the regenerator 3. Although the temperature is increased by the absorbed heat, the temperature is relatively high. Therefore, the concentrated absorbent D2 heated by the heating means 10 in the regenerator 3 is heated to a high temperature in the regenerated concentrated absorbent heat exchanger 6 to increase the temperature. On the other hand, the concentrated absorbent D2 Is sent to the absorber 2 after the temperature is lowered and distributed to the cooler heat exchanger 5. Thereby, the energy for heating the diluted absorbent D1 in the heating means 10 and the energy for cooling the concentrated absorbent D2 in the absorber heat exchanger 5 can be saved, and the reduction of the COP value can be prevented. Can do.

The dilute absorbent D1 supplied to the regenerator 3 is regenerated and separated into the concentrated absorbent D2 and the water vapor S that are heated by the heating means 10 and have an increased lithium bromide concentration. The concentrated absorbent D2 is returned to the absorber 2 due to the pressure difference between the regenerator 3 and the absorber 2, and in the process, the diluted absorbent D1 is used in the regenerated concentrated absorbent heat exchanger 6 as described above. The temperature decreases due to heat exchange. The concentrated absorbent D2 whose temperature has been lowered is circulated through the absorber heat exchanger 5 and cooled to absorb the water vapor S by heat exchange with the cooling medium C supplied from the outside of the absorption refrigerator 100. Is done. The temperature of the concentrated absorbent D2 depends on the temperature of the cooling medium C, but is about 32 ° C. to 35 ° C. The concentrated absorbent D2 cooled to the vicinity of the above temperature is Sprayed in a mist form and mixed with the water vapor S so that the water vapor S is easily absorbed. At this time, the COP value increases as the temperature of the cooling medium C decreases.
Accordingly, the temperature of the concentrated absorbent D2 is cooled to the limit that can be cooled by the cooling medium C to prevent the absorption capacity of the concentrated absorbent D2 from being lowered, and the overcooling of the diluted absorbent D1 existing in the absorber 2 is also prevented. The temperature of the concentrated absorbent D2 can be made closer to the temperature of the cooling medium C, and the COP value can be prevented from decreasing.
Further, the water vapor S regenerated in the regenerator 3 flows through the refrigerant flow passage 8 and is transferred to the condenser 4, and exchanges heat with the cooling medium C flowing through the condenser heat exchanger 4 a in the condenser 4. Water L is generated by liquefaction, and the heat of condensation can be discharged to the outside of the absorption refrigerator 100 by releasing the condensation heat to the cooling medium C. This water L flows through the refrigerant flow passage 8, passes through the throttle valve T <b> 1, and flows into the evaporator 1 in a state where the pressure is reduced. As described above, the evaporator 1 is provided with the evaporator heat exchanger 1a through which the cooling target medium U flows, and the water L flowing into the evaporator 1 exchanges heat with the cooling target medium U. The vapor S is evaporated to generate the water vapor S, the cooling target medium U is cooled by the heat of evaporation, and the cold heat can be supplied to the outside of the absorption refrigeration machine 100, and the water vapor S is transferred to the absorber 2. The above operation is repeated.

Next, the case where the opening degree of the valve on the bypass path 9 side in the three-way valve A is adjusted will be described.
As described above, when the valve on the bypass path 9 side in the three-way valve A is closed, the concentrated absorbent D2 supplied to the absorber 2 only by the absorber heat exchanger 5 and the regenerated concentrated absorbent heat exchanger 6. However, depending on the cooling load, the opening degree of the valve on the bypass path 9 side of the three-way valve A is adjusted to regenerate a part of the diluted absorbent D1 supplied from the absorber 2 to the regenerator 3 The concentrated absorbent D2 supplied from the vessel 3 to the absorber 2 is directly merged, and the temperature of the concentrated absorbent D2 is lowered and supplied to the absorber heat exchanger 5 and the absorber 2.
Specifically, a part of the diluted absorbent D1 that flows through the forward path 7a of the absorbent circulation path 7 and is supplied from the absorber 2 to the regenerator 3 is circulated to the bypass path 9, and the bypass path 9 is circulated. The diluted absorbent D1 and the concentrated absorbent D2 circulated from the regenerator 3 are merged between the regenerated concentrated absorbent heat exchanger 6 and the absorber heat exchanger 5 in the return path 7b, and the absorber 2 side The three-way valve A is opened so that the flow rate can be supplied to the absorber 2, and the flow rate of the rare absorbent D1 to the absorber 2 and the flow rate to the regenerator 3 are adjusted.
Thereby, the relatively low temperature diluted absorbent D1 and the relatively high temperature concentrated absorbent D2 supplied from the absorber 2 to the regenerator 3 are merged and mixed, and the concentrated absorption in which the diluted absorbent D1 is mixed. The liquid D2 can be supplied to the absorber heat exchanger 5 with the temperature lowered, and the flow rate of the cooling medium C for heat exchange in the absorber heat exchanger 5 can be made appropriate. Further, since it is not necessary to supply all of the relatively low temperature diluted absorbent D1 supplied from the absorber 2 to the regenerator 3 to the regenerator 3, the heating means 10 in the regenerator 3 uses the diluted absorbent D1. The heat for heating can be saved. Thereby, a suitable driving | running state can be ensured according to cooling load, and the fall of a COP value can be prevented.
The opening degree of the three-way valve A can be appropriately adjusted based on the temperatures in the absorber 2 and the regenerator 3, the temperatures of the rare absorbent D1, the concentrated absorbent D2, the cooling medium C, and the hot water H, the flow rate, and the like. In addition, by adjusting the output of the pump P, the operation state of the absorption chiller 100 can be controlled to a desired state.
The point that the concentrated absorbent D2 supplied to the absorber 2 can be cooled by the absorber heat exchanger 5 and the regenerated concentrated absorbent heat exchanger 6 is that the valve on the bypass path 9 side in the three-way valve A is closed. Since it is the same as the case where it exists, description is abbreviate | omitted.

[Reference form]
(1) In the above embodiment, the absorption refrigerator 100 is configured so that the concentrated absorbent D2 supplied into the absorber 2 and the water vapor S are mixed using the sprayer 11 as a mixing unit. Not limited to this, any device capable of appropriately mixing the concentrated absorbent D2 and the water vapor S can be used without any limitation. For example, as shown in FIG. 2, an absorption refrigerator using an ejector 12 200.
Specifically, an ejector 12 is provided between the absorber 2 and the absorber heat exchanger 5 in the return path 7b of the absorption liquid circulation path 7, and the concentrated refrigerant cooled by the absorber heat exchanger 5 flowing through the return path 7b. By mixing the absorbing liquid D2 as the driving fluid of the ejector 12 and mixing the water vapor S as the suction fluid, the concentrated absorbing liquid D2 and the water vapor S are made into fine particles so that the mixing state is good and reliable mixing is possible. The absorption efficiency can be improved by allowing the concentrated absorbent D2 to easily absorb the water vapor S. This makes it possible to improve the absorption capacity of the concentrated absorbent D2 without providing a drive source such as a pump that requires power when mixing the water vapor S, and eliminates the energy consumed by the pump and the like. , COP value can be improved.
In the above embodiment, the throttle valve T2 is provided in the return path 7b of the absorbing liquid circulation path 7. However, in this reference embodiment, the ejector 12 plays the role of the throttle valve T2.
Other configurations are the same as those in the above embodiment, and thus the description thereof is omitted.

[Another embodiment]
(1) In the above embodiment, an aqueous solution of lithium bromide is used as an absorbent and water is used as a refrigerant. However, the present invention is not limited to this, and an absorbent that can appropriately perform absorption, regeneration, etc. in an absorption refrigerator Any combination of refrigerants can be used without particular limitation. For example, an aqueous ammonia solution can be used as the absorbing liquid and ammonia can be used as the refrigerant.

(2) In the above embodiment, the bypass path 9 is provided between the forward path 7a and the return path 7b of the absorption liquid circulation path 7. However, if the overcooling of the absorption liquid in the absorber 2 can be appropriately prevented, this bypass path A configuration without 9 is also possible.

(3) In the said embodiment, although it comprised so that the warm water H was distribute | circulated to the heat exchanger tube as the heating means 10 and the concentrated absorption liquid D1 was heated, if it is an apparatus which can heat the concentrated absorption liquid D2 favorably. For example, a gas burner or a steam heating device can be used.

(4) In the above-described embodiment, the single-effect absorption refrigerator has been described as the absorption refrigerator 100. However, the absorption refrigerator can be used without particular limitation as long as it can prevent a decrease in the COP value. It can also be configured as a double-effect or triple-effect absorption refrigerator.

(5) In the above embodiment, the three-way valve A is provided at a location where the bypass passage 9 is joined on the return path 7b of the absorption liquid circulation path 7, but the absorption liquid D flowing through the absorption liquid circulation path 7 and the bypass path 9 is used. If the regenerator 3 and the absorber 2 can be supplied at an appropriate flow rate and temperature, the three-way valve A is provided on the forward path 7a of the absorption liquid circulation path 7 at a location branched from the bypass path 9 without providing the three-way valve A. A configuration is also possible.

  Providing an absorption refrigeration machine that prevents energy absorption without reducing the absorption capacity of the absorption liquid and prevents a decrease in the coefficient of performance (COP value) by preventing overcooling of the absorption liquid in the absorber To do.

DESCRIPTION OF SYMBOLS 1 Evaporator 2 Absorber 3 Regenerator 4 Condenser 5 Heat exchanger for absorber 6 Regenerated concentrated absorption liquid heat exchanger 7 Absorption liquid circulation path 7a Outbound path 7b Return path 9 Bypass path 11 Sprayer (mixing means)
100, 200 Absorption refrigerator S Water vapor (refrigerant vapor)
L Water (refrigerant liquid)
D Absorbing liquid D1 Diluted absorbing liquid D2 Concentrated absorbing liquid C Cooling medium P Pump A Three-way valve T1, T2 Throttle valve

Claims (2)

An evaporator, an absorber, a regenerator, and a condenser, and an absorption liquid circulation path through which an absorption liquid circulates between the absorber and the regenerator,
Refrigerant is absorbed in the absorber to produce a diluted absorbent,
In the regenerator, the refrigerant is evaporated to generate a concentrated absorbent, and the absorption refrigerator is operated.
An absorber heat exchanger for cooling the concentrated absorbent flowing from the regenerator to the absorber by heat exchange with a cooling medium introduced from the outside is provided in the absorption liquid circulation path outside the absorber,
An absorption refrigerator having a cooling medium flow path configured to allow the cooling medium to flow through the absorber heat exchanger and the condenser heat exchanger in the condenser to be discharged to the outside. The absorption liquid circulation path is configured to include a forward path through which the diluted absorbent is circulated from the absorber to the regenerator, and a return path through which the concentrated absorbent is circulated from the regenerator to the absorber;
2. The bypass path for directly introducing a part of the diluted absorbent flowing through the forward path to the upstream side of the absorber heat exchanger in the return path is provided between the forward path and the return path. Absorption refrigerator.

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