JPH063329B2 - Absorption refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an absorption refrigerating machine used for taking out cold water for cooling, ice making or a heat pump by an absorption refrigerating cycle, and particularly to a rectifier and a dephlegmator. The present invention relates to an improvement of an absorption refrigerator provided.

(B) Conventional technology The combination of refrigerant and absorbent is Freon 22-tetraethyl glycol dimethyl ether type, trifluoroethanol-
In an absorption refrigerator having an organic type such as N-methyl-2-pyrrolide type, the absorbent gas is mixed in the refrigerant gas generated in the generator. Further, when the refrigerant gas is liquefied as it is and supplied to the evaporator, the function of the absorption refrigerator is not sufficiently exerted because the purity of the refrigerant is low.

Therefore, as disclosed in, for example, Japanese Patent Laid-Open No. 58-221357, absorption refrigeration having a rectifier and a partial condenser between a generator and a condenser is a conventional technique for increasing the purity of a refrigerant. A machine (hereinafter referred to as an absorption refrigerator of this type) is used.

(C) Problems to be Solved by the Invention In the conventional absorption refrigerator of this kind as described above, the refrigerant having a higher purity is supplied to the evaporator as compared with the absorption refrigerator having no rectifier and separator. Although it can be supplied, when the heat exchange between the refrigerant gas and the cooling fluid of this gas in the dephlegmator is insufficient, the reflux amount of the refrigerant liquefied in the dephlegmator to the rectifier tends to be insufficient. At the same time, the saturated vapor pressure and temperature of the refrigerant gas at the uppermost part of the rectifier become high, so that there is a problem that the rectification efficiency of the rectifier decreases and the purity of the refrigerant cannot be kept high.

The present invention has been made in view of the above problems, and an object thereof is to provide an absorption refrigerator of this type capable of maintaining a high purity of the refrigerant.

(D) Means for solving the problems The present invention, as a means for solving the above problems, in this type of absorption refrigerator, the refrigerant gas temperature near the top of the rectifier and the refrigerant in the condenser While detecting the liquid temperature, the amount of heat exchanged between the refrigerant and the cooling fluid in the dephlegmator is adjusted so that the refrigerant gas temperature approaches the refrigerant liquid temperature.

(E) Action In this main absorption refrigerator according to the present invention, the temperature of the refrigerant gas in the uppermost portion of the rectifier is kept low close to the refrigerant liquid temperature value in the condenser, and the refrigerant is liquefied by the partial condenser. Since it has the action (function) of preventing the shortage of the reflux amount of the rectifier to the rectifier, it prevents the deterioration of the rectification efficiency of the rectifier, and the refrigerant gas at the top of the rectifier and the refrigerant liquid in the condenser. It becomes possible to maintain a substantially equilibrium state, and the purity of the refrigerant supplied to the evaporator side can be kept high.

(F) Embodiments FIG. 1 is a schematic configuration explanatory view showing an embodiment of an absorption refrigerator of this type according to the present invention.

In FIG. 1, (1) has a combustion heating chamber (2) for kerosene, city gas, etc., and absorbs a large amount of refrigerant (hereinafter referred to as “concentrated liquid”) A gas generator for gasification and separation, (3) a rectifier for separating the absorbent component from the rising refrigerant gas stream, and (4) a gas stream sent from the rectifier (3). This is a partial condenser for cooling the heat exchanger (5) and finally separating the absorbent component. (6)
Has a heat exchanger (7), is liquefied in the condenser (8), and is a pressure reducing valve.
An evaporator that heats and vaporizes the liquid refrigerant that is stepped down and sprayed in (9) from the heat exchanger (7), and (10) is the absorption in which the refrigerant is separated in the generator (1) and the refrigerant concentration becomes low. A liquid (hereinafter referred to as a dilute liquid) is decompressed by a pressure reducing valve (11) and sprayed from a disperser (12) to absorb the vaporized refrigerant gas in an evaporator (6),
This continuously absorbs heat from the fluid flowing through the heat exchanger (7), and supplies the heated fluid to the outside of the machine via the heat exchangers (13) (14) (5) (operating as an absorption heat pump). Alternatively, it is an absorber capable of supplying the fluid cooled when flowing through the heat exchanger (7) to the outside of the machine (operating as an absorption refrigerator), and the concentrated liquid that has absorbed the refrigerant in this absorber (10) is The gas flow rising from the generator (1) is sprayed from the liquid disperser (17) through the solution heat exchanger (16) to the packing material (18) below the rectifier by the absorption liquid pump (15). While flowing in contact with, it flows down to the generator (1) and the refrigerant is separated again. In addition, (19) is a generator
It is a liquid receiver placed above (1). Further, (20) is a packing material above the rectifier (3), and the refrigerant liquefied in the separator (4) is sprinkled on this packing material. And (2
1), (22), (23) are pipes for flowing dilute liquid, (24), (25), (26) Pipes for flowing concentrated liquid, (27) is a pipe line for flowing absorbing liquid and refrigerant, (28)
Is a pipe through which the absorption liquid flows, (29) and (30) pipes through which the refrigerant gas flows, (31) and (32) are pipes through which the refrigerant liquid flows down, and (33) is a pipe through which the refrigerant liquid flows back.

Further, (34) and (35) are tubes connected to the heat exchanger (7), (36),
(37), (38), (39) are pipes connected in series with the heat exchangers (10), (14, (5), and (40) is a pipe (38) via a three-way valve (V). , (3
It is a bypass pipe connected to 9).

(S ₁ ) and (S ₂ ) are near the top of the rectifier (3) and the condenser, respectively.
It is a temperature detector provided at the bottom of (8), and (C) controls the opening of the three-way valve (V) while receiving signals from the temperature detectors (S ₁ ) and (S ₂ ). By adjusting the amount of heat exchanged between the refrigerant gas in the compressor (4) and the fluid in the heat exchanger (5) (for example, cooling water), the difference between the temperature detected by the temperature detectors (S ₁ ) and (S ₂ ) Is a controller that adjusts so that it approaches zero.

Next, an operation example of the absorption refrigerating machine (hereinafter referred to as this machine) configured as described above will be described. Here, it is assumed that this machine is used as a refrigerator and cooling water is sequentially circulated through the heat exchangers (10), (14) and (5).

If the temperature of the cooling water flowing into the heat exchanger (5) of the dephlegmator (4) rises while the outside air temperature rises while the machine is operating, the refrigerant in the dephlegmator (4) As the amount of liquefaction begins to decrease, the vapor pressure near the top of the dephlegmator (4) and rectifier (3) begins to rise. Then, the reflux amount of the refrigerant liquid from the dephlegmator (4) to the rectifier (3), that is, the amount of the refrigerant liquid sprayed to the filler (20) is reduced, and the rectification efficiency of the rectifier (3) is reduced. As it begins to decrease, the difference between the saturation temperature of the refrigerant gas near the top of the rectifier (3) and the temperature of the refrigerant liquid in the condenser (8) becomes large, and its equilibrium state begins to break down, leading to the evaporator (6). The purity of the refrigerant flowing down decreases.

In such a case, the temperature detector (S ₁ ), (S
₂ ) signal, via the controller (C), the opening on the three-way valve (V) bypass pipe (40) side is decreased, while the opening on the heat exchanger (5) side is increased and the decompressor (4 The amount of heat exchanged between the refrigerant and the cooling water in) is controlled so as to increase. As a result, the demultiplexer (4)
As the amount of liquefied refrigerant increases, the vapor pressure near the top of the rectifier (3) also drops. Then, the difference between the temperature of the refrigerant gas in the vicinity of the top of the rectifier (3) and the temperature of the refrigerant liquid in the condenser (8) is returned to the original amount of the reflux amount of the refrigerant to the rectifier (3). When was close to zero as before, the three-way valve
The opening of (V) is fixed.

In this way, in this machine, the temperature of the refrigerant gas in the uppermost portion of the rectifier (3) and the temperature of the refrigerant liquid in the condenser (8) are made substantially equal to maintain a gas-liquid equilibrium state, and Since the heat exchange amount between the refrigerant and the cooling water in the dephlegmator (4) is adjusted so as to prevent the refrigerant liquid from flowing back from the separator (4) to the rectifier (3) insufficiently, the evaporator is adjusted. The purity of the refrigerant flowing down to (6) is almost 1
Can be kept close to 00%.

When the absorption refrigerator of this type is started, the wetting of the packing material (20) is insufficient and the rectification efficiency of the rectifier (3) is low, and the gas-liquid has not reached the equilibrium state. Detector (S ₁ ), (S
There is a large difference in the temperature detected in ₂ ). Therefore, when the machine is started up, the three-way valve (V) is controlled via the controller (C). Then, increase the liquefaction amount of the refrigerant in the partial condenser (4),
Since (20) is quickly wetted and the gas-liquid equilibrium state is brought about in a short time, the performance at the time of starting this machine is improved.

FIG. 2 is a diagram showing a schematic configuration of a partial condenser in another embodiment of the absorption refrigerating machine according to the present invention, and the same components as those in FIG. 1 are designated by the same reference numerals. . In this embodiment, instead of the heat exchanger (5) shown in FIG. 1, the heat exchangers (H ₁ ), (H ₂ ), (H ₃ ) and (H ₄ ) are replaced by a decompressor (4). Further, instead of the cooling water from the heat exchanger (14), cooling water from another water source is supplied to these heat exchangers. (P ₁ ), (P ₂ ), (P ₃ ) and (P ₄ ) are tubes connected to heat exchangers (H ₁ ), (H ₂ ), (H ₃ ) and (H ₄ ), respectively. (V ₁ ), (V ₂ ), (V ₃ ), and (V _{series 4} ) are tubes (P ₁ ),
An on-off valve provided for (P ₂ ), (P ₃ ) and (P ₄ ). And
These on-off valves are connected to the temperature detector (S ₁ ) via the controller (C),
The amount of heat exchanged between the refrigerant gas and the cooling water in the dephlegmator (4) is controlled by opening / closing control by a signal from (S ₂ ). The temperature detector (S ₂ ) is a decompressor (4).
You may prepare for the bottom.

(G) Effect of the Invention As described above, in the absorption refrigerator of this type according to the present invention, the temperature of the refrigerant gas in the vicinity of the uppermost portion of the rectifier is set close to the temperature of the refrigerant liquid in the condenser. A control mechanism is provided for adjusting the amount of heat exchanged between the refrigerant and the cooling fluid in the dephlegmator so as to maintain the liquid equilibrium state and prevent the insufficient amount of the refrigerant liquefied by the dephlegmizer from flowing back to the rectifier. Because
The purity of the refrigerant sent to the evaporator can be kept high, and the performance of this type of absorption refrigerator can be satisfactorily exhibited.

Further, according to the present invention, the performance at the time of starting up this type of absorption refrigerator can also be improved.

[Brief description of drawings]

FIG. 1 is a schematic structural explanatory view showing an embodiment of an absorption refrigerator of this type according to the present invention, and FIG. 2 is a schematic structure of a partial condenser in another embodiment of the absorption refrigerator of the present invention. FIG. (1) ... Generator, (3) ... Rectifier, (4) ... Decompressor, (5) ... Heat exchanger, (6) ... Evaporator, (8) ... Condenser, (10) ... Absorption Bowl, (20) ...
Filler, (29), (30), (31), (32), (33) ... Pipe, (36), (3
7), (38), (39) ... Pipe, (40) ... Bypass pipe, (C) ... Controller, (H ₁ ), (H ₂ ), (H ₃ ), (H ₄ ) ... Heat exchanger , (P ₁ ), (P ₂ ),
(P ₃ ), (P ₄ ) ... tube, (S ₁ ), (S ₂ ) ... temperature detector, (V) ... three-way valve, (V ₁ ), (V ₂ ), (V ₃ ), (V ₄ )… Open / close valve.

Claims (1)

[Claims] 1. An absorption refrigerator comprising a generator, a rectifier, a partial condenser, a condenser, an evaporator and an absorber connected by piping.
Refrigerant gas temperature near the top of the rectifier by adjusting the amount of heat exchanged between the refrigerant and the cooling fluid in the separator while detecting the refrigerant gas temperature near the top of the rectifier and the refrigerant liquid temperature in the condenser An absorption refrigerating machine comprising a control mechanism for keeping the temperature of the refrigerant close to the temperature of the refrigerant in the condenser.