JPH05280822A - Absorption refrigeration system - Google Patents

Abstract

PURPOSE:To improve absorption efficiency within an absorber. CONSTITUTION:In an absorption refrigeration system including a generator 1, a condensor 2, an evaporator 3 and an absorber 4, wherein an ejector 28 is installed at an inlet side of the absorber 4, working liquid from the generator 1 is fed to the ejector 28 as a driving flow, and refrigerant vapor from the evaporator 3 is fed as a secondary flow, the working liquid and the refrigerant vapor are mixed with each other as vapor-liquid mixture flow and further supplied to the absorber, a vapor-liquid separator 30 is installed at the downstream side of the ejector 28 and the vapor-liquid mixture flow BR generated by the ejector 28 is separated again into the working liquid B and the refrigerant vapor R. In addition, the working liquid B and the refrigerant vapor R and supplied in such a manner that they may become an opposing flow within the absorber 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption refrigeration system.

[0002]

2. Description of the Related Art In an absorption refrigeration system, a generator for rectifying a mixed working fluid vapor of a refrigerant and an absorbing liquid generated from a working fluid obtained by mixing a refrigerant and an absorbing liquid to concentrate a refrigerant component,
A condenser for condensing the concentrated gas refrigerant, an evaporator for evaporating the liquid refrigerant condensed by the condenser, and an absorber for absorbing the refrigerant vapor evaporated by the evaporator into the working liquid supplied from the generator. In this case, in the evaporator, the lower the internal pressure of the evaporator is, the more the evaporation action is promoted. On the other hand, the higher the internal pressure of the absorber is, the more the absorption action is promoted.

An invention intended to improve the efficiency of an absorption refrigerating apparatus by applying the above principle is disclosed in, for example, Japanese Patent Laid-Open No. 62-225871.

The invention of this conventional example uses an ejector 128 as shown in FIG. 5 to drive a high-pressure hydraulic fluid B supplied from a generator as a driving flow, and, on the other hand, a low-pressure refrigerant vapor supplied from an evaporator. R is a secondary flow, both are supplied to the absorber as a mixed flow BR in the ejector 128, and the refrigerant vapor is absorbed in the working liquid in the absorber. In the case of this conventional example, the refrigerant vapor from the evaporator is sucked into the ejector 128 at a negative pressure, so that the internal pressure of the evaporator is reduced and the evaporation action is promoted, while the absorber is connected to the generator. The working fluid from is introduced while maintaining a relatively high pressure, which has the effect of increasing the internal pressure of the absorber and promoting the absorbing action.

[0005]

By the way, since the ejector has a gas-liquid mixing function, when such an ejector is used, the absorber is usually an in-vessel mixed absorption type absorber, and the countercurrent is generated. It cannot be configured as an absorption absorber.

In the in-vessel mixed absorption type absorber, the absorption action at the end of the absorber is inactive, and it is difficult to obtain high absorption efficiency as a whole. On the other hand, in the countercurrent absorption type absorber,
Since the refrigerant vapor from the evaporator is introduced at the end portion of the absorber where the absorption proceeds to some extent and the absorption is less likely to occur, the absorption efficiency is improved as a whole.

According to the present invention, the advantages of using the ejector in the absorption refrigerating apparatus are utilized, and further, the drawbacks (the absorber becomes the in-container mixed absorption type) when the ejector is used are attempted to be improved. It is a thing.

[0008]

In the present invention, in order to achieve the above object, as shown in FIG. 1, a mixture operation of a refrigerant and an absorption liquid generated from a working liquid in which a refrigerant and an absorption liquid are mixed. Generator 1 for rectifying liquid vapor to concentrate refrigerant components
A condenser 2 for condensing the concentrated gas refrigerant component; an evaporator 3 for evaporating the liquid refrigerant condensed by the condenser 2;
In an absorption type refrigeration system having an absorber 4 for absorbing the refrigerant vapor evaporated in the evaporator 3 into the working fluid supplied from the generator 1, the generator 1 is provided at the inlet side of the absorber 4.
From the evaporator 3 as a secondary flow, and the ejector 28 as a secondary flow, and the gas-liquid mixed flow BR mixed and produced by the ejector 28 as the working fluid B and the refrigerant vapor R.
And a gas-liquid separator 30 for separating the liquid and the refrigerant are provided, and the working liquid B and the refrigerant vapor R separated by the gas-liquid separator 30 are allowed to flow in the absorber 4 in opposition to each other. is there.

[0009]

In explaining the operation of the absorption refrigeration system according to the present invention, the absorption refrigeration system shown in FIG. 1 is used as an example of the absorption refrigeration system.

In FIG. 1, reference numeral 1 is a generator, 2 is a condenser, 3 is an evaporator, and 4 is an absorber.

In this absorption refrigeration system, when the working fluid (for example, aqueous ammonia solution) B (Ba) is heated in the generator 1, the working fluid (for example, ammonia) and the absorption fluid are removed from the working fluid.
A hydraulic fluid vapor Ga of (for example, water) is generated, and the hydraulic fluid vapor Ga rises through the rectifier section 13 formed in the container 11 of the generator 1.

In the rectifying section 13, the mixed working liquid vapor Ga of the refrigerant and the absorbing liquid rising from below comes into contact with the concentrated solution B (Bc) supplied from the absorber 4 to bring the refrigerant in the working liquid vapor into contact. The concentration rises and is concentrated in the rectifier section 13 (Gc),
Further, the gas refrigerant Ra _{1 that} has been subjected to partial condensation in the partial condenser unit (described later) 14 is supplied to the condenser 2. In the condenser 2, the refrigerant gas Ra ₁ is liquefied and becomes the liquid refrigerant Rb.

The liquid refrigerant Rb is evaporated in the evaporator 3 and becomes the gas refrigerant Ra ₂ again. The gas refrigerant Ra ₂ is fed to the absorber 4, and the gas refrigerant Ra ₂ is introduced into the absorber 4 via the ejector 28 and the gas-liquid separator 30 provided according to the present invention. It

This will be described in more detail below. The ejector 28 is supplied with a high-pressure working liquid (dilute solution) Ba from the generator 1 as a driving flow, while the evaporator 3 is supplied with a low-pressure gas refrigerant Ra. ₂ is supplied as a secondary stream. The gas-liquid mixed flow BR of the working liquid (diluted solution) and the gas refrigerant generated in the ejector 28 flows into the gas-liquid separator 30 in the subsequent stage, where it is separated into the working liquid B and the gas refrigerant R again. Then, one of the gas-liquid separated working fluid B is supplied to the upper stage of the absorber 4, and the other gas refrigerant R is supplied to the lower stage of the absorber 4 to be a counterflow in the absorber 4. , High efficiency absorption. The hydraulic fluid B (Bc) that has absorbed the gas refrigerant R is supplied to the generator 1 by the pump 51. As described above, the basic refrigeration cycle of the absorption refrigeration system to which the present invention is applied is executed.

[0015]

In the absorption type refrigerating apparatus to which the present invention is applied shown in FIG. 1, the ejector 28 forcibly sucks the gas refrigerant Ra ₂ in the evaporator 3, so that the internal pressure in the evaporator 3 decreases. Then, the evaporation of the refrigerant is promoted to enhance the cooling effect, and the pressure (static pressure) in the gas-liquid separator 30 is increased by the supply of the high-pressure hydraulic fluid from the generator 1, which causes the absorber 4 There is an effect that the pressure inside the container also rises and the absorption action of the refrigerant in the absorber 4 is enhanced. Further, by providing the gas-liquid separator, it becomes possible to configure the absorber as a counter flow absorption type absorber. As a result, it is possible to obtain a small-sized and high-capacity absorption refrigeration system as compared with the conventional absorption refrigeration system of the same type.

[0016]

2 and 3 show circuit configurations of a solution and a refrigerant in an absorption refrigerating apparatus for cooling and heating operation according to an embodiment of the present invention. In FIGS. 2 and 3, reference numeral 1 is a generator, 2 is a condenser during the cooling operation shown in FIG. 2, and is a first heat exchanger serving as an evaporator during the heating operation shown in FIG. The second heat exchanger 4 which serves as a heat exchanger and serves as a condenser during heating operation is an absorber.

By the way, since the principle of the absorption refrigeration cycle itself is already well known, how the refrigeration cycle is executed in the absorption refrigeration apparatus of FIGS. 2 and 3 will be briefly described below. ..

First, the cooling operation shown in FIG. 2 will be described. In the cooling operation, when the working fluid (ammonia aqueous solution in this embodiment) is heated by the heater (burner) 19 in the generator 1, the working fluid becomes a refrigerant ( A mixed vapor (working liquid vapor) Ga of (ammonia) and an absorption liquid (water) is generated, and this mixed vapor Ga rises through the rectifier section 13 formed in the container 11 of the generator 1.

In the rectification section 13, liquid storage sections D _{1 to} D ₅ having an appropriate number of stages (five in this embodiment) are formed, and the operation is to be supplied to the generator 1 from the side of the absorber 4 described later. Liquid (concentrated solution)
Bc is from the upper liquid storage D ₅ to the lower liquid storage D ₄ , D ₃ , D
It is designed to flow down to ₂ , D ₁ .

In the rectifier section 13, every time the mixed working fluid vapor of ammonia and water rising from below passes through each storage rack (D _{1 to} D ₅ ), a temperature drop and a concentrated solution from above are produced. The concentration of ammonia in the working fluid vapor increases due to the contact with the working fluid vapor, and the ammonia-water mixed vapor Gc concentrated in the rectifier portion 13 is further divided into the upper dephlegmator portion (details will be described later) 1
The water is separated in 4 to become about 99.8% ammonia gas (gas refrigerant). This gas refrigerant is indicated by arrows A ₁₁ and A in FIG.
_As indicated by ₁₂ , the gas is supplied to the first heat exchanger 2 serving as a condenser via the first four-way switching valve 31. In the first heat exchanger 2, the air is cooled by the fan 68 to release the heat of condensation and the ammonia gas is liquefied to become ammonia liquid (liquid refrigerant).

This liquid refrigerant is passed through an inter-refrigerant heat exchanger (details will be described later) 32 as shown by an arrow A ₁₃ in FIG. Circulating water from the indoor unit (circulating water piping 3
5 circulates and circulates in 5) to evaporate (circulating water is cooled and becomes a cooling heat source for cooling), and becomes a gas refrigerant (ammonia gas) again. This gas refrigerant is sent to the above-mentioned inter-refrigerant heat exchanger 32 through the second four-way switching valve 36 as shown by arrow A ₁₄ in FIG. 2, and the liquid refrigerant from the heat exchanger 2 is there.
After precooling (passing through the coil 32C), the first four-way switching valve 31 and the second four-way switching valve 36, the ejector 28 and the gas-liquid separator 30 (in FIG. 2) are pre-cooled. Arrow A
₁₅ , A ₁₆ , A ₁₇ ) and fed to the absorber 4.

In the absorption refrigeration system of this embodiment, an integral ejector 28 and a gas-liquid separator 30 as shown in FIG. 4 are used. In the example of FIG. 4, the container 9 of the gas-liquid separator 30
A refrigerant suction chamber 82 that introduces the refrigerant vapor Ra ₂ into the ejector 28 through a pipe 83 is attached to the side surface of No. 1, and the working fluid Ba from the generator 1 is passed through the center of the refrigerant suction chamber 82. The hydraulic fluid pipe 81 to be introduced is attached toward the inside of the gas-liquid separator container 91. The tip of the hydraulic fluid pipe 81 is a nozzle portion 84 having a small passage cross-sectional area. The refrigerant suction chamber 82 is opened toward the inside of the gas-liquid separator container 91, and the opening portion thereof is concentrically surrounded by the second nozzle portion 84 of the hydraulic fluid pipe 81.
The large-diameter nozzle portion 85 is provided.

The ejector 28 shown in FIG. 4 produces an accelerated and depressurized action in the first small-diameter nozzle portion 84 when the high-pressure (for example, 18ata) hydraulic fluid Ba is supplied from the generator 1 through the pipe 81, whereby The refrigerant vapor Ra ₂ supplied from the heat exchanger 3 is sucked through the pipe 83, and becomes the gas-liquid mixed flow BR from the second large diameter nozzle portion 85 to become the gas-liquid separator 3
It flows into 0.

The gas-liquid mixed flow BR introduced into the gas-liquid separator 30 collides with the inner surface of the front concave portion 92 to lose its kinetic energy (the dynamic pressure is converted to the static pressure), The working liquid component B of the gas-liquid mixed flow BR is separated downward, and the other refrigerant vapor component R is separated upward. In FIG. 4, reference numeral 94 is an eliminator for promoting the gas-liquid separation action.

The one working fluid B separated as described above is supplied to the upper stage portion of the absorber 4 as indicated by an arrow L ₁ in FIG. 2, and the other refrigerant vapor R is indicated by an arrow A in FIG.
It is supplied to the lower part of the absorber 4 as shown at ₁₇ . That is, in the absorber 4 of the illustrated embodiment, the working fluid B and the refrigerant vapor R are supplied as counter flows through the present invention.

The absorber 4 serves to absorb the gas refrigerant R into the working fluid B again, and carries out the same action in the following manner.

That is, a sprayer 42 for the working fluid B is provided at the uppermost stage in the container 41 of the absorber 4, and the gas-liquid separator 30 is provided to the sprayer 42 as indicated by an arrow L _1. The hydraulic fluid B is supplied from. This hydraulic fluid B is stored in the absorber container 4
The gas refrigerant R sprayed from the sprayer 42 and supplied into the absorber container 41 in 1 absorbs the gas refrigerant R to form a concentrated solution Bc, which falls into the container bottom liquid pool 49.

The working liquid (concentrated solution) Bc stored in the container bottom liquid pool 49 is pumped by the pump 51 as indicated by arrows L ₂ , L ₃ , L ₄ and L ₅ in FIG. After heat exchange (absorption) with the heat exchanger 29 in the partial condenser and the heat exchanger 46 in the first absorber, the heat is supplied to the uppermost liquid storage shelf D ₅ in the generator 1. In the absorber 4, in addition to the first heat exchanger 4 in the absorber (heat exchanger for recovering a part of absorption heat generated in the absorber 4 into working fluid), And a third two in-absorber heat exchangers 47, 48 are provided.
That is, the second heat exchanger 47 in the absorber in the upper stage is a heat exchanger that heats the water fed by the pump 54 as necessary, that is, acts as a hot water heater, and in the lower stage. A certain third heat exchanger in the absorber 48
Is for releasing the absorption heat generated in the absorber 4 to the atmosphere, and the third heat exchanger 48 in the absorber has an arrow from the air-cooled heat exchanger (radiator) 5 by the pump 53. S _{1 to} S ₃
Cooling water is supplied through the cooling water piping 60 as indicated by, and the residual absorption heat is released by this cooling water. The radiator 5 is blown by the fan 69 and air-cooled.

Incidentally, two three-way switching valves 62, 63 are provided in the cooling water piping 60, and by switching the three-way switching valves 62, 63, the radiator 5 and the third absorber The cooling water piping 60 with the heat exchanger 48 is opened and closed.

Next, the heating operation shown in FIG. 3 will be described. During the heating operation, first, the first and second four-way switching valves 31, 3 of the refrigeration circuit in the cooling operation shown in FIG.
6 is switched, and the flow direction of the gas refrigerant (ammonia gas) flowing through the refrigeration circuit is switched (arrows A _{21 to} A ₂₉ ).
At the same time, the two three-way switching valves 62, 63 in the cooling water pipe line 60 are switched, and the cooling water flow between the radiator 5 and the third heat exchanger 48 in the absorber is cut off. instead, by switching the three-way valve 61 in the circulation water pipe passage 35, the third absorber in the heat exchanger 48 is connected to the circulating water pipe passage 35 (arrow C ₂₂ ~C _23).

In the refrigerating circuit of FIG. 3, the gas refrigerant (concentration 99.8%) generated in the dephlegmator section 14 of the generator 1 has a first four-way switching valve as shown by arrows A _{21 to} A _23. 31 and second
Flows into the second heat exchanger 3 acting as a condenser through the four-way switching valve 36, and is condensed there by exchanging heat with the circulating water supplied from the indoor unit through the circulating water piping 35. .. The circulating water is heated by this and becomes a heat source for heating in the indoor unit. In this embodiment, the circulating water to the indoor units, three-way as the condenser by switching the switching valve 61, 62 and 63 arrows before entering the second heat exchanger 3 C _22, C ₂₃ As shown by, passes through the third heat exchanger 48 in the absorber. That is, in the absorption refrigeration system of FIG.
The absorption heat obtained in the absorber internal heat exchanger 48 and the condensation heat obtained in the second heat exchanger 3 are used as the heating heat source.

The refrigerant liquefied in the second heat exchanger 3 acting as a condenser is decompressed by the decompressor 33 as shown by an arrow A ₂₄ , and then the first heat exchanger 2 acting as an evaporator.
Is evaporated (air heat exchange evaporation by the fan 68) and further supplied to the ejector 28 via the first four-way switching valve 31, the inter-refrigerant heat exchanger 32, and the second four-way switching valve 36 (arrow A _{2 Five}
~ A ₂₈ ).

The gas-liquid mixing action of the working liquid and the refrigerant vapor in the ejector 28, the gas-liquid separating action of the gas-liquid separator 30, the generation, rectification and partial condensation of the water-ammonia mixed working liquid vapor in the generator 1. The action, the action of absorbing the ammonia gas refrigerant in the absorber 4, etc. are the same as in the case of the cooling operation shown in FIG. 2, and the flow of the working liquid (concentrated solution and dilute solution) during that time is the same as in the case of FIG. The description is omitted because it is similar.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of a basic circuit of an absorption refrigerating apparatus which is a target of the present invention.

FIG. 2 is a refrigeration circuit diagram of the absorption refrigeration apparatus for cooling and heating according to the embodiment of the present invention during a cooling operation.

FIG. 3 is an explanatory diagram of a changing state of the refrigeration circuit shown in FIG. 2 during heating operation.

FIG. 4 is an enlarged sectional view of an ejector and a gas-liquid separator used in the embodiments of FIGS. 2 and 3.

FIG. 5 is a longitudinal sectional view of an ejector used in a conventional absorption refrigeration system.

[Explanation of symbols]

1 is a generator, 2 and 3 are heat exchangers that are condensers or evaporators, 4 is an absorber, 5 is a radiator, 12 is a steam generator, 1
3 is a rectifier section, 14 is a partial condenser section, 19 is a heater, 28 is an ejector, and 30 is a gas-liquid separator.

Claims (1)

[Claims] 1. A generator (1) for rectifying a refrigerant component by rectifying a mixed working liquid vapor of a refrigerant and an absorbing liquid generated from a working liquid obtained by mixing a refrigerant and an absorbing liquid; and the concentrated gas refrigerant component. A condenser (2) for condensing the refrigerant, an evaporator (3) for evaporating the liquid refrigerant condensed by the condenser (2), and a refrigerant vapor evaporated by the evaporator (3) for the generator (1). An absorption type refrigerating device having an absorber (4) for absorbing the working fluid supplied from the generator, wherein the working fluid (Ba) from the generator (1) is provided at the inlet side of the absorber (4). Is used as a driving flow and a refrigerant vapor from the evaporator (3) is used as a secondary flow, and a gas-liquid mixed flow (BR) mixed and generated by the ejector (28) is used as a working fluid (B). Refrigerant vapor
(R) is provided with a gas-liquid separator (30) which separates the working liquid (B) and the refrigerant vapor (R) separated by the gas-liquid separator (30) in the absorber (4). An absorption type refrigeration system characterized in that they are made to flow in opposition.