JP3133538B2 - Absorption refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption type refrigerator such as an absorption refrigerator or an absorption chiller / heater which performs a heat exchange operation by a required heat pump action using an absorption liquid in which a heat absorber is mixed with a vaporizable refrigerant. It relates to a refrigerator.

[0002]

2. Description of the Related Art As an apparatus of this type, for example, an absorption refrigerator using an absorption liquid such as an aqueous solution of lithium bromide in which an absorbent is mixed with lithium bromide and water is used. Is configured as the absorption chiller / heater 100 of the first embodiment.

In FIG. 3, a thick solid line indicates a liquid conduit for a refrigerant liquid, an absorbing liquid, cooling water and the like, and a double line indicates a vapor line for a refrigerant vapor. 1
Low concentration absorbing solution stored at the bottom of
A description will be made with reference to FIG.

[0004] The dilute solution 2a enters the high temperature regenerator 5 via the pipe 3 by the pump P1. Since the high temperature regenerator 5 is heated from below by a heater 6 such as a burner, the diluted liquid 2a
The refrigerant contained therein evaporates and separates into a high-temperature, medium-concentration absorbent, that is, the intermediate liquid 2b and the refrigerant vapor 7a.

[0005] The high-temperature intermediate liquid 2 b enters a high-temperature-side heat exchanger 9 via a pipe 8. In the heat exchanger 9, the high-temperature intermediate liquid 2
b gives heat to the dilute solution 2a passing through the pipe 3 to radiate heat, and after the temperature drops, enters the low-temperature regenerator 11 via the pipe 10.

In the low-temperature regenerator 11, the refrigerant vapor 7 a is sent to the radiating pipe 11 A in the low-temperature regenerator 11 for heating the intermediate liquid 2 b via the pipe 21 and is heated.
The refrigerant contained in b evaporates and separates into a high-temperature, high-concentration absorbent, that is, a concentrated liquid 2c, and refrigerant vapor 7b.

The high-temperature concentrated liquid 2 c enters the low-temperature heat exchanger 13 via the pipe 12. In the heat exchanger 13, the high-temperature concentrated liquid 2 c gives heat to the diluted liquid 2 a passing through the pipe 3, radiates heat, and after reaching a medium temperature, passes through the pipe 14 and spreads the sprayer 1 in the absorber 1.
A, and sprays from many holes of the sprayer 1A.

The sprayed concentrated liquid 2c is cooled by cooling water 32a flowing through a cooling pipe 1B in the absorber 1. When flowing down the outside of the cooling pipe 1B, the concentrated liquid 2c absorbs and dilutes the refrigerant vapor 7c entering from the adjacent evaporator 26, returns to the low-temperature diluted liquid 2a, and completes the absorption liquid. The absorption liquid circulation is repeated.

Next, the refrigerant circulation system will be described with the refrigerant vapor 7C entering the absorber 1 as a starting point. The refrigerant vapor 7c is
As described in the above-described absorbent circulation system, the concentrated liquid 2c dispersed from the sprayer 1A in the absorber 1 absorbs the diluted liquid 2a.
Into the refrigerant vapor 7a in the high-temperature regenerator 5.

The refrigerant vapor 7a enters the radiating pipe 11A of the low-temperature regenerator 11 via the pipe 21, gives heat to the intermediate liquid 2b to radiate heat, condenses into the refrigerant liquid 24a, and then changes to the pipe 22.
And enters the bottom of the condenser 23.

The condenser 23 is provided with a refrigerant vapor 7b which enters through a number of passages 11B between the adjacent low-temperature regenerators 11b.
To the cooling water 32a passing through the cooling pipe 23A in the condenser 23.
And condenses the refrigerant vapor 7b to produce a low-temperature refrigerant liquid 24a.
To The refrigerant liquid 24a passes through a pipe 25 and passes through an evaporator 26.
, And accumulates in the lower part of the evaporator 26 to become the refrigerant liquid 24b.

The pump P2 supplies the refrigerant liquid 24b to the pipe 28
Is sent to the sprayer 26A, and the spraying from a number of holes of the sprayer 26A is repeated. Sprayed refrigerant liquid 24b
Is a fluid to be heated which passes through a heat exchange pipe 26B in the evaporator 26,
That is, the cold / warm water 35a is cooled. During this cooling, the refrigerant liquid 24b absorbs heat from the cold / warm water 35a and evaporates to become refrigerant vapor 7c.
Then, the refrigerant returns to the absorber 1 through a large number of passages 26C, and the circulation of the refrigerant is completed.

As described above, by the double regeneration operation of the high-temperature regenerator 5 and the low-temperature regenerator 11, the heat exchange pipe 2 in the evaporator 26 is circulated while circulating the absorbing liquid and the refrigerant, that is, the heat operating fluid.
6B, that is, the heat-operated fluid supplied from the pipe 36, that is, the cooling / rewarming water 35a, is cooled by the heat exchange pipe, and the chilled water 35b is cooled from the pipe 37 to the cooling target device such as an indoor cooling device (FIG. (Not shown) as a heat-receiving operation fluid for cooling is referred to as a double-effect cooling operation, and is also referred to as a cooling operation because it is mainly used for cooling.

On the other hand, the refrigerant vapor 7a evaporated in the high-temperature regenerator 5 and the high-temperature intermediate liquid 2b to be put in the high-temperature heat exchanger 9 are provided in the pipelines 41 and 42 which are bypassed to the evaporator 26. The open / close valves V1 and V2 are opened to return directly to the evaporator 26 and the absorber 1, and the refrigerant liquid 24b to be sprayed from the sprayer 26A is bypassed between the pipe 28 and the pipe 4. The on-off valve V3 provided in the passage 43 is opened to mix the refrigerant liquid 24b into the absorbing liquid 2a, and the operation of only the high-temperature regenerator 5 without using the low-temperature regenerator 11 allows the absorption liquid circulation and the refrigerant circulation to be performed. While performing, the heat exchange pipe 26B in the evaporator 26, that is, the heat exchange pipe, that is, the heat-operated fluid provided from the pipe 36, that is, the cold / warm water 35a is heated, and the hot water 35b is supplied from the pipe 37. Heating equipment (not shown) such as indoor heating equipment The operation given as use the heat operation fluid, say warming operation (boiler operation), mainly due to the use for heating, and also said heating operation.

During the heating operation, that is, during the heating operation, the cooling of the absorber 1 and the condenser 23 is not necessary.
By stopping the operation of the pump P3, the supply of the cooling water 32a from the pipeline 31 is stopped.

The control section 50 is a control section for controlling and processing the above operation of the absorption chiller / heater 100. As described above, the control section 50 opens and closes the on-off valves V1, V2, V3, and operates the pumps P1, P2.
By controlling the operation / stop of the second, switching operation between the cooling operation and the heating operation is performed, and during each operation,
Cold / hot water 35 to be given to the equipment to be cooled or to be heated
In order to maintain b at a predetermined temperature, necessary operation signals given from a setting operation device (not shown) or the like, and cold / hot return water 3
Temperature detector S for detecting the temperature of 5a and cold / hot water 35b
1. S2, a heating controller 6A for adjusting the heating amount of the heater 6 and the like based on each detection signal given from the temperature detectors S3 and S4 for detecting the temperatures of the cooling water 32a and the cooling return water 32b. By controlling, a steady temperature control operation is performed. For this reason, the equipment to be controlled is of an electric type.

In the absorption chiller / heater 100 configured to circulate the absorption liquids 2a, 2b, and 2c, when the double-effect operation is stopped, a portion of the absorption liquid that has become the concentrated liquid 2d, that is, If the absorbent between the pipe 12, the heat exchanger 13 and the pipe 14 is left in a high-concentration state, the components of the absorbent crystallize and precipitate, and the pipe is blocked, causing a failure. Before stopping completely,
In a state in which the heating controller 6A is closed and the heating by the heater 6 is stopped, the pump P1 is operated to circulate the absorbing liquid while opening the on-off valve V3 and mixing the refrigerant liquid 24b into the diluted liquid 2a, thereby absorbing the absorbing liquid. The operation is stopped after the dilution operation for diluting the concentration of the whole liquid, particularly the concentration of the portion of concentration 2a, is performed. In addition, since this dilution operation is usually performed with a load, if the pump P1 is operated with heating stopped without opening the on-off valve V3, the evaporator 2 can be operated.
Since the refrigerant evaporates at 6, the concentration of the entire absorbent can be reduced, so that the dilution operation does not necessarily have to be performed with no load. The configuration of the absorption chiller 100 provided with this type of dilution operation was published in July 1990 by the assignee of the present applicant, Sanyo Electric Co., Ltd., “Absorption chiller / heater / absorption chiller C series catalog '90 -7”, February 1989. Published by Tsuki Ohm “Knowledge of Air Conditioning Equipment Business” or Japanese Patent Laid-Open No. 57-202.
465 and the like.

Further, as shown in FIG. 1, for example, a high-temperature regenerator 5 in the above absorption refrigerator is provided with a heating tank 5A for heating only the diluted liquid 2a, and a refrigerant vapor from the heated diluted liquid 2a. 7a and a separation tank 5C for separation into an intermediate liquid 2b, and a pipe 5B between the heating tank 5A and the separation tank 5C.
The construction of the absorption refrigerator 100 provided with
0940 and the like.

[0019]

In the above-described absorption chiller / heater 100, when the operation is switched from the cooling operation to the heating operation or when the cooling operation is stopped, troubles such as crystallization of the absorbing solution may occur. In order to prevent this, it is necessary to perform a dilution operation for diluting the absorbent.

In this dilution operation, the heater 6 is stopped and the pump P1 is operated to circulate the absorbing liquid while the load side is in an operating state by passing the cold / hot water 35b through the heat exchange pipe 26B in the evaporator 26. Therefore, the refrigerant liquid is supplied to the heat exchange tube 26 of the evaporator 26.
It flows down to B and removes heat from the loaded cold / warm water 35a to evaporate, lowering the concentration of the dilute solution, so that the concentration of the entire absorbing solution is reduced. .

However, in such a configuration of the dilution operation, first, during the dilution operation, it is necessary to prevent the temperature of the cold / hot water 35b from dropping excessively and to cause freezing damage to each part, and to promote the evaporation of the refrigerant liquid. Therefore, it is necessary to keep the load side in the operating state, and there is a disadvantage that the dilution operation cannot be performed by the independent operation of only the absorption refrigerator 100 side.

Secondly, since the cooling capacity during the cooling operation remains in each part, it takes a considerably long time, for example, about 6 to 7 minutes, until the concentration of the concentrated liquid 2c is sufficiently reduced. There is an inconvenience of cost. For this reason, there is a problem that provision of such an inconvenient device is desired.

[0023]

According to the present invention, there is provided an absorbent circulating system for circulating an absorbent obtained by mixing the above-mentioned absorbent into a refrigerant through heat exchange equipment such as a high-temperature regenerator and an absorber.
A refrigerant circulation system that circulates the refrigerant vapor and the refrigerant liquid by the above refrigerant through heat exchangers such as condensers and evaporators, and cooling that passes cooling water to required heat exchangers such as absorbers and condensers. A system is provided, and the operation target fluid passing through the heat exchange pipe in the evaporator is switched between a heating operation for heating and a cooling operation for cooling, and the cooling operation is stopped, or
An absorption refrigerator having a dilution operation for diluting the concentration of an absorbent in an absorption liquid during a switching operation from a cooling operation, wherein a portion of the refrigerant vapor in the condenser and a refrigerant in the evaporator are provided. Refrigerant vapor bypass means for providing a bypass connecting the steam portion, bypass valve means for providing an on-off valve interposed in the bypass, and dilution operation means for performing a dilution operation by opening the on-off valve. A first configuration to be provided, and in addition to this configuration, the above-described side path is a first side path, and the above-mentioned on-off valve is a first on-off valve. Refrigerant-liquid-absorbing-liquid-side-pass means for providing a second bypass connecting the portion of the absorbing liquid in the inside; second-side-pass valve means for providing a second on-off valve interposed in the second bypass; Opening the first on-off valve and the second on-off valve and stopping the flow of the cooling water to perform the dilution operation. By a second configuration in which the operation unit is obtained by adapted to solve the above problems.

[0024]

At the beginning of the dilution operation, since the cooling capacity during the cooling operation still remains in the refrigerant vapor in the condenser, the refrigerant vapor in the evaporator removes the cold / hot water in the heat exchange pipe in the evaporator. Although cooling causes supercooling, in the first configuration, the pressure / temperature in the evaporator is increased by opening a bypass connecting the refrigerant vapor portion in the condenser and the refrigerant vapor portion in the evaporator. To prevent evaporation of the refrigerant liquid, and to equalize the pressure in the refrigerant condenser and the pressure in the evaporator to reduce the amount of refrigerant liquid flowing from the condenser to the evaporator. The supercooling of certain cold / hot water can be suppressed. Therefore, it works so that the dilution operation can be performed even when the operation on the load side is stopped.

Further, according to the second configuration, in addition to suppressing the supercooling of the cold / hot water by equalizing the pressure, the flow of the cooling water is stopped to suppress the condensation of the refrigerant vapor in the condenser. Then, the amount of the refrigerant liquid flowing from the condenser to the evaporator is further reduced to suppress the supercooling of the cold / hot water, and the side path connecting the refrigerant liquid in the evaporator and the absorption liquid in the absorber is opened. In addition, the refrigerant liquid is forcibly mixed into the absorbing liquid to promote a decrease in the concentration of the absorbing liquid. Therefore, it works so that the dilution operation can be completed in a short time.

[0026]

An embodiment will be described below with reference to FIGS.
In these figures, the portions denoted by the same reference numerals as those in FIG. 3 are portions having the same functions as the portions denoted by the same reference numerals described with reference to FIG.

Since FIGS. 1 and 2 show the construction of the absorption refrigerator, the cold / hot water 35a / 35b in FIG. 3 is the cold water 35a / 35b. Further, in the case of being configured as an absorption chiller / heater that switches between cooling and heating, a portion corresponding to the pipeline 41 and the on-off valve V1 bypassing between the separator 5C and the evaporator 26 in FIG. Must be provided also in the configurations of FIGS.

[First Structure] The first structure shown in FIG. 1 is similar to the structure shown in FIG.
a ・ 2b ・ 2c ・ 2d circulating through the heat exchange equipment such as the high temperature regenerator 5 / absorber 1, the refrigerant vapor 7a ・ 7b and the refrigerant liquid 24a ・ 24b by the above refrigerant
And a cooling system that circulates cooling water 32a to required heat exchange devices such as the absorber 1 and the condenser 23. The operation to be heated, which passes through the heat exchange pipe 26B in the evaporator 26, ie, the cold / hot water 35a / 35b, is switched between a heating operation for heating and a cooling operation for cooling, and the cooling operation is performed. In the absorption refrigerating machine 100 configured to perform the diluting operation for diluting the concentration of the absorbent in the absorbing liquid during the stop operation or the switching operation from the cooling operation, the refrigerant vapor 7b in the condenser 23 and Refrigerant vapor bypass means for providing a bypass 61 connecting the portion of the refrigerant vapor 7c in the evaporator 26, bypass valve means for providing an on-off valve V4 interposed in the bypass 61, and control operation of the control unit 50 Open the above on-off valve It has become one provided the dilution operation means for performing operation.

Hereinafter, a specific description will be given.
Is configured by a heating tank 5A, a pipeline 5B, and a separation tank 5C instead of the high-temperature regenerator 5 in FIG. 3 as described above.

In the part of the conduit 28 attached to the evaporator 26, a bubble pump 63 having a heat exchange radiating tube 62 is provided instead of the pump P2 in FIG.
Is circulating.

Further, a pipe 61 is provided for connecting the refrigerant vapor 7b in the condenser 23 and the refrigerant vapor 7C in the evaporator 26, and is provided in the middle of the pipe 61.
An electric open / close valve V4, for example, an electromagnetic valve is interposed, and the control signal from the control unit 50 controls the open / close valve V4 to open only during the dilution operation.

This control signal is output when a control processing function provided in the control unit 50, for example, a program stored in a microcomputer, enters a control processing stage of the dilution operation.

By this control, during the dilution operation, the pressure in the condenser 23 and the pressure in the evaporator 26 are equalized through the pipe line 61, and the refrigerant liquid 24a in the condenser 23 is discharged to the evaporator 2
The flow given to the sprayer 26A in 6 is reduced,
Since the refrigerant liquid in the evaporator 26 is suppressed, the heat exchange pipe 2
The operation is performed so as to suppress cooling of the cold / hot water 35a and 35b in 6B.

[Second Configuration] The second configuration shown in FIG. 2 is similar to the first configuration shown in FIG. Path means, first side path valve means using the on-off valve V4 as a first on-off valve, a portion of the refrigerant liquid 24b in the evaporator 26, and the absorbing liquid 2 in the absorber 1.
a means for providing a second bypass 43 connecting to the portion a, and a second on-off valve V interposed in the second bypass 43
3, a second bypass valve means, a first on-off valve V4 and a second
And a dilution operation means for performing the dilution operation by stopping the flow of the cooling water 32a while opening the on-off valve V3.

To be more specific, in FIG. 2, the portions indicated by the same reference numerals as those in FIG. 1 have the same functions as the portions denoted by the same reference numerals in FIG. The portion of the valve V3 and the pump P3 has the same function as the portion of the same reference numeral in FIG. 3, and opens and closes the on-off valve V4 and the on-off valve V3 during the dilution operation by the control signal from the control unit 50. Control is performed to stop P3.

With this control, during the dilution operation, the pressure in the condenser 23 and the pressure in the evaporator 26 are equalized through the pipe 61 and the cooling pipe in the condenser 23 is stopped by stopping the pump P3. Since the cooling of 23A is stopped, they act synergistically to reduce the flow of the refrigerant liquid 24a in the condenser 23 to the sprayer 26A in the evaporator 26, and to reduce the cooling / cooling in the heat exchange pipe 26B. The operation is performed so as to suppress the cooling of the warm waters 35a and 35b.

At the same time, the refrigerant liquid 24b in the evaporator 26 is mixed into the dilute liquid 2a or the flow in the absorber 1 via the pipe line 43, so that the intermediate liquids 2b and 2c and the concentrated liquid 2d are mixed. In order to promote the reduction of the concentration, the dilution operation will be performed in a short time.

[Modified Embodiment] The present invention can be implemented with the following modifications.

(1) In the first configuration and the second configuration, the high temperature regenerator 5 is configured in the same manner as the high temperature regenerator 5 in FIG.

(2) In the first configuration and the second configuration, the on-off valve V4 operates the refrigerant liquid 24 in the condenser 23 for a predetermined time from the start of the dilution operation, for example, at the start of the dilution operation.
It is configured to open for a time proportional to the amount of a.

(3) In the first configuration, the pump P3 is stopped simultaneously with opening the on-off valve V4.

(4) In the first configuration and the second configuration, the portion of the bubble pump 63 is modified similarly to the portion by the pump P2 in FIG.

[0043]

As described above, according to the present invention, during the dilution operation, in the first configuration, the pressure in the condenser and the pressure in the evaporator are equalized, and the pressure in the evaporator is reduced from the condenser. In order to reduce the amount of the refrigerant liquid flowing into the evaporator and to suppress the evaporation of the refrigerant liquid in the evaporator, the cooling / hot water in the heat exchange tube in the evaporator, that is, the superheated working fluid is not supercooled. Even if the operation on the load side is stopped, the dilution operation can be performed safely without causing freezing damage.

In the second configuration, the pressure in the condenser and the pressure in the evaporator are equalized, and the suppression of the condensation in the condenser by stopping the cooling water operates synergistically. In order to further reduce the amount of refrigerant liquid flowing from the condenser to the evaporator and to suppress evaporation of the refrigerant liquid in the evaporator,
Even if the operation on the load side is stopped, the dilution operation can be performed more safely without causing freezing damage.In addition, since the side path connecting the refrigerant liquid in the evaporator and the absorbent in the absorber is opened, absorption is performed. It has features such as accelerating the concentration reduction of the liquid and completing the dilution operation in a short time.

[Brief description of the drawings]

1 and 2 show an embodiment of the present invention, and FIG. 3 shows a conventional technique. The contents of each figure are as follows.

FIG. 1 is a specific configuration diagram of a main part.

FIG. 2 is a specific configuration diagram of a main part.

FIG. 3 is a schematic diagram of a block configuration.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Absorber 1A Sprayer 1B Cooling pipe 2a Rare liquid 2b Intermediate liquid 2c Concentrated liquid 3 Pipeline 5 High temperature regenerator 5A Heating tank 5B Pipeline 5C Separation tank 6 Heater 6A Heating regulator 7a Refrigerant vapor 7b Refrigerant vapor 7c Refrigerant vapor 8 Pipeline 9 Heat exchanger 10 Pipeline 11 Low temperature regenerator 11A Heat radiator pipe 11B Passage 12 Pipeline 13 Heat exchanger 14 Pipeline 21 Pipeline 22 Pipeline 23 Condenser 23A Cooling pipe 24a Refrigerant liquid 24b Refrigerant liquid 25 Pipeline 26 Evaporator 26A Sprayer 26B Cooling pipe 28 Pipeline 31 Pipeline 32a Cooling water 32b Cooling return water 33 Pipeline 34 Pipeline 35a Cold / hot return water 35b Cold / hot water 36 Pipeline 37 Pipeline 41 Pipeline 42 Pipeline 43 pipeline 50 control unit 61 pipeline 62 radiator tube 63 auxiliary evaporator 100 absorption refrigerator P1 pump P2 pump P3 pump S1 temperature detector S2 temperature Degree detector S3 Temperature detector S4 Temperature detector V1 On-off valve V2 On-off valve V3 On-off valve V4 On-off valve

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-51-118143 (JP, A) Jiko 60-23649 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25B 15/00 306

Claims (2)

(57) [Claims] 1. An absorbent circulating system for circulating an absorbent mixed with an absorbent into a refrigerant through heat exchangers such as a high-temperature regenerator and an absorber, and a condenser / evaporation of a refrigerant vapor and a refrigerant liquid by the refrigerant. A refrigerant circulation system that circulates through heat exchange devices such as a heat exchanger, and a cooling system that passes cooling water to required heat exchange devices such as the absorber and the condenser are provided for heat exchange in the evaporator. The operation fluid to be heated passing through the pipe is switched between a heating operation for heating and a cooling operation for cooling, and the cooling operation is stopped, or at the time of the switching operation from the cooling operation, An absorption refrigerator configured to perform a dilution operation for diluting the concentration of the absorbent, comprising: a bypass connecting a part of the refrigerant vapor in the condenser and a part of the refrigerant vapor in the evaporator. Refrigerant vapor bypass means provided; Absorption refrigerating machine characterized by comprising a bypass valve means for providing an on-off valve which, the dilution operation means for performing the dilution operation by opening the on-off valve. 2. An absorbent circulating system for circulating an absorbent in which an absorbent is mixed in a refrigerant through heat exchangers such as a high-temperature regenerator and an absorber, and a condenser and an evaporator for evaporating refrigerant vapor and refrigerant liquid by the refrigerant. A refrigerant circulation system that circulates through heat exchange devices such as a heat exchanger, and a cooling system that passes cooling water to required heat exchange devices such as the absorber and the condenser are provided for heat exchange in the evaporator. The operation fluid to be heated passing through the pipe is switched between a heating operation for heating and a cooling operation for cooling, and the cooling operation is stopped, or at the time of the switching operation from the cooling operation, An absorption type refrigerator configured to perform a dilution operation for diluting a concentration of the absorbent, wherein a first portion connecting a portion of the refrigerant vapor in the condenser and a portion of the refrigerant vapor in the evaporator is connected. Refrigerant vapor bypass means for providing a bypass, First bypass valve means for providing a first opening / closing valve interposed in the bypass, and a second bypass connecting a portion of the refrigerant liquid in the evaporator and a portion of the absorbent in the absorber. A second bypass valve means for providing a second on-off valve interposed on the second bypass path; a first on-off valve and the second on-off valve; A dilution operation means for performing the dilution operation by opening the cooling water and stopping the flow of the cooling water.