JP2004340424A - Absorption refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorption refrigerator using a simple method for effectively collecting heat from an internal cycle. <P>SOLUTION: The absorption refrigerator comprises an evaporator E, an absorber A, a condenser C, a regenerator GL, a solution heat exchanger, a solution pump, and an absorbed solution passage and a refrigerant solution passage connecting these together. Herein, a collection heat exchanger SC is provided in the C for heat exchange between diluted solution discharged from the A and refrigerant vapor flowing into the GL and the C in sequence. The SC can be arranged adjacent to the heat conduction part of the C, stored in a GL/C container 2 and preferably formed with a plate heat exchanger or a snaking pipe. In the SC, a means V1 can be provided for controlling the flow amount of the diluted solution to be supplied. Furthermore, the absorption refrigerator can be constructed in multiple stages to operate the E and the A in a plurality of pressure stages and formed with multiple utility cycles or single or double utility cycles. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an absorption refrigerator, and more particularly to a high-efficiency absorption refrigerator capable of recovering heat from an internal cycle in an effective and simple manner.
[0002]
[Prior art]
[Patent Document 1] Japanese Patent Publication No. 56-1537 discloses a method of improving the efficiency of an absorption refrigerator, which is roughly classified into a method of recovering heat from an external heating source and a method of recovering heat from an internal cycle.
For example, as heat recovery from an external heating source, it is known to provide a drain heat exchanger for exchanging heat between a vapor drain and an absorbing solution after heating and concentrating a solution in a high-temperature regenerator.
In addition, heat recovery from the internal cycle is performed by exchanging heat between the refrigerant condensate after heating and concentrating the absorption solution in the low-temperature regenerator and the dilute solution from the absorber, and raising the temperature of the dilute solution. Methods for increasing efficiency are known. (Japanese Patent Publication No. 56-1537)
[0003]
Alternatively, a method is known in which heat exchange is performed between a relatively hot concentrated solution flowing into the absorber and a relatively low-temperature dilute solution exiting the absorber, and the cycle efficiency is increased by raising the temperature of the dilute solution. I have.
These methods involve the recovery of sensible heat, and have the problem that the heat exchange efficiency is poor due to the temperature change of each medium.
In recent years, with the increasing trend to prevent global warming, higher efficiency has been demanded.
An effective method of recovering the latent heat of the refrigerant vapor flowing from the regenerator into the condenser with an absorbing solution has not yet been disclosed.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide an inexpensive absorption refrigerator capable of effectively recovering heat of an internal cycle.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides an absorption refrigerator having an evaporator, an absorber, a condenser, a regenerator, a solution heat exchanger, a solution pump, an absorption solution path connecting these devices, and a refrigerant path. Wherein a recovery heat exchanger for exchanging heat between the dilute solution exiting the absorber and the refrigerant vapor flowing from the regenerator to the condenser is provided.
In the absorption refrigerator, the recovery heat exchanger is disposed adjacent to the heat transfer section of the condenser and can be housed inside the regenerator and the condenser container. The recovery heat exchanger may be provided with a means for controlling the flow rate of the dilute solution to be supplied.
Further, the absorption refrigerator of the present invention can be configured in multiple stages so that the evaporator and the absorber operate at a plurality of pressure stages, and the absorption refrigerator is formed in a multiple effect cycle or a single effect cycle. You can also.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
According to the present invention, the latent heat of the refrigerant vapor flowing into the condenser from the regenerator is recovered by the dilute solution exiting the absorber, so that the heat recovery between the media having a relatively small temperature difference can be effectively performed. It is like that.
That is, in the recovery of the latent heat of the refrigerant vapor flowing into the condenser from the regenerator, heat exchange can be performed while the temperature of the refrigerant vapor is kept constant, so that the temperature difference between the heat exchange media is effectively reduced. Can be used.
Next, the present invention will be described in detail with reference to the drawings.
In the figure, GH is a high temperature regenerator, GL is a low temperature regenerator, LX is a low temperature solution heat exchanger, HX is a high temperature solution heat exchanger, SC is a recovery heat exchanger, DX is a drain heat exchanger, A is an absorber, E is an evaporator, AH is a high-pressure absorber, AL is a low-pressure absorber, EH is a high-pressure evaporator, EL is a low-pressure evaporator, RP is a refrigerant pump, SP is a solution pump, V1 is a control valve, and 20 to 27 are absorption solutions. A path, 30 to 33 are refrigerant paths, 50 and 51 are chilled water paths, 52 to 54 are cooling water paths, 60 and 61 are heat source paths, and 70 is a temperature sensor.
[0007]
In FIG. 1, the dilute solution that has absorbed the refrigerant vapor from the evaporator E is supplied from the absorber A to the recovery heat exchanger SC via the solution path 20A by the solution pump SP. The dilute solution flowing inside the heat transfer section of the SC exchanges heat with the refrigerant vapor generated in the low-temperature regenerator GL, and recovers a part of the latent heat of the refrigerant vapor. The dilute solution heated by the SC passes through the solution path 20B and is introduced into the low-temperature solution heat exchanger LX. After LX, it follows the same circulation path as the conventional absorption refrigerator.
In FIG. 1, a control valve V1 for the circulation path of the dilute solution is provided. This appropriately controls the flow rate of the dilute solution supplied to the recovery heat exchanger SC. For example, by opening and closing the control valve V1 by the temperature sensor 70 provided in the solution path 20B, it is possible to perform optimal heat recovery according to the load state or to use the SC to adjust the pressure loss in the SC. You can also.
[0008]
Of course, without providing this control valve, the dilute solution from the solution pump SP may be supplied to the whole amount SC.
Further, in FIG. 1, the SC is installed at the upper part of the condenser C, but is not limited to this, and may be installed at a side part or a lower part of the condenser C. The refrigerant vapor from the low-temperature regenerator GL is preferentially guided to the SC, and the SC is housed inside the low-temperature regenerator and the condenser container 2, so that a compact configuration can be achieved.
Although FIG. 1 is described in a so-called branch flow, it is needless to say that the present invention is not limited to this cycle and can be applied to other cycles such as a series flow and a reverse flow.
[0009]
Hereinafter, other examples will be briefly described.
FIG. 2 is a flow configuration diagram showing another example of the present invention, in which the absorber A and the evaporator E are configured in a plurality of stages. In FIG. Although it is composed of two stages, it is not specified in two stages.
The relatively high-temperature cold water returned from the air-conditioning load flows into the high-pressure evaporator EH, is cooled, is further cooled by the low-pressure evaporator EL, and is supplied to the air conditioner. In the case of such a configuration, the high-pressure evaporator EH and the low-pressure evaporator EL operate at an evaporation temperature of, for example, 8 ° C., 5 ° C., etc., and operate in combination with the evaporator. Absorber AL allows the dilute solution concentration exiting the absorber to be significantly reduced.
As a result, the solution circulation amount can be reduced and the concentration difference between the dilute solution and the concentrated solution can be set large, so that the efficiency of the absorption refrigerator can be further increased.
[0010]
In this method, it is possible to further reduce the concentration of the dilute solution exiting the absorber A by designing the temperature difference of the cold water to be larger than the normal 5 ° C., for example, about 8 ° C.
In FIG. 2, the flow direction of the cooling water is shown to flow in the order of the high-pressure absorber AH, the low-pressure absorber AL, and the condenser C, but the flow is not limited to this. For example, the cooling water may be flown in parallel to the high-pressure absorber AH and the low-pressure absorber AL, or it may be flown from the condenser C to the absorber A side. By flowing the cooling water in parallel to the high-pressure absorber AH and the low-pressure absorber AL, the temperature of the dilute solution flowing out of the absorber A can be reduced, so that the heat recovery in the SC can be performed more effectively. Become.
[0011]
FIG. 3 shows a cross-sectional configuration diagram when the recovery heat exchanger SC is formed of a meandering tube (indicated by an arrow X in FIG. 1).
An inlet and an outlet for the dilute solution paths 20A and 20B are provided on the side plate 75 of the low-temperature regenerator and the condenser vessel 2, and the dilute solution introduced from the solution path 20A flows inside the meandering pipe constituting the SC, and After the heat exchange with the refrigerant vapor introduced into the outside of the pipe, the refrigerant flows out from the path 20B. With such a configuration, it is possible to simply and inexpensively configure the tube sheet without performing a large number of holes in the tube sheet as compared with the case where a large number of straight pipes are used.
Further, there is an advantage that the present invention can be implemented only by adding a simple change to the standard machine.
Further, in FIG. 3, only one meandering tube is shown, but a plurality of meandering tubes may be used.
[0012]
FIG. 4 is a cross-sectional configuration diagram when the recovery heat exchanger SC is configured by a plate heat exchanger (indicated by the arrow X in FIG. 2).
The inlet and outlet of the dilute solution paths 20A and 20B are provided on the side plate 75 of the low-temperature regenerator and condenser vessel 2, and the dilute solution introduced from the solution path 20A is supplied to each plate 80 of the plate heat exchanger constituting the SC. Flows through the inside of the plate and exchanges heat with the refrigerant vapor introduced outside the plate, and then flows out of the path 20B.
The function and effect are almost the same as those in the example of FIG. 3, but further downsizing by the plate heat exchanger can be expected.
Although the examples of the invention described above are described in the double-effect cycle, they are, of course, not limited thereto, and may be applied to a single-effect, a triple-effect, etc., and a single-double effect. Although FIGS. 1 and 2 show a steam type absorption refrigerator, the invention is also applied to a direct-fired absorption refrigerator and an absorption chiller / heater.
[0013]
【The invention's effect】
According to the present invention, by adopting the above configuration, it has become possible to provide a high-efficiency absorption refrigerator by an inexpensive and simple method capable of effectively recovering the heat of the internal cycle.
[Brief description of the drawings]
FIG. 1 is a flow configuration diagram showing an example of an absorption refrigerator of the present invention.
FIG. 2 is a flow configuration diagram showing another example of the absorption refrigerator of the present invention.
FIG. 3 is a cross-sectional configuration diagram showing one example of a recovery heat exchanger of the present invention.
FIG. 4 is a sectional view showing another example of the recovery heat exchanger of the present invention.
[Explanation of symbols]
GH: high temperature regenerator, GL: low temperature regenerator, SC: recovery heat exchanger, DX: drain heat exchanger, LX: low temperature solution heat exchanger, HX: high temperature solution heat exchanger, A: absorber, E: evaporation AH: High pressure absorber, AL: Low pressure absorber, EH: High pressure evaporator, EL: Low pressure evaporator, RP: Refrigerant pump, SP: Solution pump, V1: Control valve, 20-27: Absorption solution path, 30 33: refrigerant path, 70: temperature sensor

Claims (6)

In an absorption refrigerator having an evaporator, an absorber, a condenser, a regenerator, a solution heat exchanger, a solution pump, an absorption solution path connecting these devices, and a refrigerant path, the dilute solution exiting the absorber is regenerated. An absorption refrigerator comprising a recovery heat exchanger for exchanging heat with refrigerant vapor flowing into a condenser from a condenser. 2. The absorption refrigerator according to claim 1, wherein the recovery heat exchanger is disposed adjacent to a heat transfer section of the condenser, and is housed inside the regenerator and the condenser container. 3. The absorption refrigerator according to claim 1, wherein the recovery heat exchanger comprises a plate heat exchanger or a meandering tube. The absorption refrigerator according to claim 1, 2, or 3, wherein the absorption refrigerator includes a unit that controls a flow rate of the dilute solution supplied to the recovery heat exchanger. The absorption refrigerator according to any one of claims 1 to 4, wherein the evaporator and the absorber are configured in multiple stages to operate at a plurality of pressure stages. The absorption refrigerator according to any one of claims 1 to 5, wherein the absorption refrigerator is formed in a multiple effect cycle or a single effect cycle.

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