JPH0424368Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a dual-effect absorption refrigerator, and is particularly suitable for cooling water in a chilled water coil by circulating a mixture of water and lithium salt. This invention relates to a dual-effect absorption refrigerator.

[Prior Art] As shown in FIG. 5, a conventional refrigerator of this type includes a high-temperature regenerator 2 that heats a dilute solution that has absorbed a refrigerant, and a refrigerant that converts the heated solution in the high-temperature regenerator 2 into a refrigerant. A separator 4 separates vapor into an intermediate concentrated solution, and the intermediate concentrated solution separated by this separator 4 is heated to a high temperature and then introduced, and the refrigerant vapor obtained in the separator 4 A low-temperature regenerator 6 that heats and condenses an intermediate concentrated solution, a condenser 8 that condenses the refrigerant vapor led through the low-temperature regenerator 6, and a condenser 8 that evaporates the liquid refrigerant condensed in the condenser 8 to produce load chilled water. an evaporator 10 that exchanges heat with the evaporator 10, and an absorber 14 to which the concentrated solution obtained in the low-temperature regenerator 6 is guided and which absorbs the refrigerant vapor evaporated in the evaporator 10 into the concentrated solution;
A pump 16 that pumps the dilute solution obtained in the absorber 14 to the high temperature regenerator 2 constitutes one circulation system, and the water in the coil 10a in the evaporator 10 is cooled. Also, separator 4
The cooling/heating switching valve 22a provided in the middle of the pipe 22 communicating with the absorber 14 is opened, and the steam from the high temperature regenerator 2 and the intermediate concentrated solution are guided to the evaporator 10 via the separator 4, and the coil The water inside 10a can also be heated.

In FIG. 5, reference numeral 18 denotes pipes 5, 5a, 5 which lead the intermediate concentrated solution from the separator 4 to the low temperature regenerator 6.
A high-temperature heat exchanger provided in the middle of b, and reference numeral 20 is a low-temperature heat exchanger provided in the middle of the pipes 7, 7a, and 7b leading the concentrated solution obtained in the low-temperature regenerator 6 to the absorber 14.

[Problem that the invention attempts to solve]

In a conventional dual-effect absorption refrigerator as shown in FIG. Yes, this allows pipe 5
a, 5b, there was a problem that the corrosion conditions of the high temperature heat exchanger 18 were worsened. In addition, the more refrigerant vapor generated in the high temperature regenerator 2 enters the intermediate concentrated solution circuit, the more effectively it is not used, and the amount of heat input to the low temperature regenerator 6 also decreases, reducing the operating efficiency of the refrigerator. The point was hot.

To deal with this problem, an orifice, capillary, or module control valve is installed in the middle of the pipe 5 to control the flow rate of the intermediate concentrated solution, thereby preventing refrigerant vapor from entering the pipe. I was getting used to it.

[Problem that the invention attempts to solve]

However, among the conventional techniques, those in which an orifice is provided in the pipe line 5 are effective in preventing refrigerant vapor from entering the pipe line 5 when the load and cooling water temperature are constant; When there were fluctuations in the water temperature, it was not possible to prevent refrigerant vapor from entering the pipe line 5. Further, even if the intrusion of refrigerant vapor could be prevented, there was a problem in that the intermediate concentrated solution would accumulate in the separator 4 more than necessary.

In addition, a capillary installed in the conduit 5 is effective for load fluctuations with a certain range or fluctuations in cooling water temperature, but in case of large load fluctuations where the refrigerating capacity fluctuates by 100% to 25%. It was not possible to adequately respond to large fluctuations in cooling water temperature, such as temperatures between 20°C and 34°C.

Furthermore, although a module equipped with a module control valve in the conduit 5 can handle large fluctuations to some extent, the control becomes complicated and the running cost increases due to increased electrical energy consumption, and furthermore, the module control valve itself is expensive. Therefore, there was a problem that the product cost was extremely high.

The present invention was devised in view of the problems of the prior art described above, and its purpose is to provide a double-effect absorption refrigerating machine that has a simple structure and is effective in preventing refrigerant vapor in the separator from penetrating into the intermediate concentrated solution feed pipe. Our goal is to provide the following.

[Means for solving problems]

The dual-effect absorption refrigerator according to the present invention includes a high-temperature regenerator that heats a dilute solution that has absorbed a refrigerant, and a separator that separates the solution heated by the high-temperature regenerator into refrigerant vapor and an intermediate concentrated solution. A low-temperature regenerator into which the intermediate concentrated solution separated by the separator is cooled and then heated and concentrated by the refrigerant vapor obtained in the separator; a condenser that condenses the refrigerant vapor guided through the
An evaporator that evaporates the liquid refrigerant condensed in this condenser and exchanges heat with the load chilled water, and a concentrated solution obtained in the low-temperature regenerator is introduced, and the refrigerant vapor evaporated in the evaporator is absorbed into this concentrated solution. In a dual-effect absorption refrigerating machine, an absorber for transporting an intermediate concentrated solution to the low-temperature regenerator and a pump for pumping the solution obtained in the absorber to the high-temperature regenerator constitute one circulation system. The present invention is characterized in that a flow rate regulator is provided in the leading pipe line for adjusting the opening area in proportion to the pressure in the separator and inversely proportional to the pressure in the condenser.

[Effect]

According to the present invention, the pipe opening area by the flow regulator is adjusted so that it is proportional to the pressure (absolute pressure) inside the separator and inversely proportional to the pressure (absolute pressure) inside the condenser. In other words, if the pressure inside the separator decreases significantly, the flow rate regulator will greatly reduce the flow path opening area, suppressing the intrusion of refrigerant vapor into the intermediate concentrated solution supply circuit, and causing the pressure inside the condenser to decrease significantly. For example, the flow rate regulator opens the flow path opening area to a large extent, making it easier for the intermediate concentrated solution in the separator to flow. [Example] Next, an example of the present invention will be described based on the drawings.

Fig. 1 is a system diagram showing an embodiment of the refrigerator of the present invention. Reference numeral 2 is a high-temperature regenerator equipped with a heating means such as a burner, and the dilute solution that has absorbed the refrigerant introduced into the regenerator is It is heated in the high-temperature regenerator, turns into steam, and is guided to the separator 4, where it is separated into refrigerant vapor and intermediate concentrated solution. The high-temperature intermediate concentrated solution obtained in the separator 2 is led to the high-temperature heat exchanger 18 through the pipe 5a, where it is cooled by heat exchange with the low-temperature dilute solution, and then passed through the pipe 5b. , a flow rate regulator 30, which will be described later, and a pipe line 5.
c and is introduced into the low temperature regenerator 6 sequentially. High-temperature refrigerant vapor is introduced from the separator 2 into the coil 6a disposed in the low-temperature regenerator 6, and the intermediate concentrated solution whose temperature has been lowered once in the high-temperature heat exchanger 18 becomes the high-temperature refrigerant flowing inside the coil 6a. Reheated by steam. That is, in the low-temperature regenerator 6, the refrigerant is evaporated from the intermediate concentrated solution to concentrate the solution, and the vapor generated at this time is introduced into the condenser 8, which is connected to the low-temperature regenerator 6 and is provided in communication. Further, the refrigerant vapor in the coil 6a is condensed by heat exchange with the intermediate concentrated solution, and this is also introduced into the condenser 8.

Inside the condenser 8 is a coil 8 through which cooling water flows.
a is provided, and the refrigerant guided into the condenser 8 from the coil 6a is further condensed by this cooling water and becomes liquid refrigerant. The liquid refrigerant obtained in the condenser 8 is introduced into the evaporator 10 and is spread onto the evaporator coil 10a by a spreader 10b. Cold water is flowing inside the coil 10a, and the sprayed liquid refrigerant takes evaporation heat from the cold water and evaporates, thereby further cooling the cold water inside the coil 10a.

On the other hand, the concentrated solution obtained by condensing in the low temperature regenerator 6 is transferred to the pipe 7a, the low temperature heat exchanger 20, and the pipe 7b.
through the absorber 14, which is in communication with the evaporator 10. In the absorber 14, there is an absorber coil 1 connected to the coil 8a disposed in the condenser 8.
4a is disposed, and the concentrated solution introduced into the absorber 14 is sprayed onto this coil 14a by a sprayer 14b. The concentrated solution obtained in the low-temperature regenerator 6 exchanges heat with the dilute solution circulating in the low-temperature heat exchanger 20 to become high temperature, and in the absorber 14,
The refrigerant vapor evaporated in the evaporator 10 is sufficiently absorbed to form a dilute solution. The absorption heat generated when this concentrated solution absorbs the refrigerant is absorbed by the cooling water flowing inside the coil 14a. The dilute solution obtained in the absorber 14 is transferred to a low temperature heat exchanger 2 by a pump 16.
0, is sent to the high temperature regenerator 2 via the high temperature heat exchanger 18.

Reference numeral 22 is a pipe that communicates the separator 4 and the absorber 14, reference numeral 22a is a cooling/heating switching valve provided in the middle of the communication pipe 22 for switching between heating operation and freezing operation, reference numeral 24 is a flow rate control valve, Reference numeral 26 denotes a fuel control valve that controls the fuel supply to the burner of the high-temperature regenerator 2, which detects the temperature of the cold water flowing in the coil 10a in the evaporator 10, and controls the flow rate control valve 24 according to the temperature. and fuel control valve 2
By operating 6, the amount of solution circulation and the amount of heat input to the high temperature regenerator 2 are controlled. As shown in FIG. 2, the flow rate regulator 30 provided between the conduit 5b and the conduit 5c has a container 32 divided into two chambers 31a and 3 by a diaphragm 34.
1b. The first chamber 31a communicates with the inside of the condenser 8 through a passage 33, and a spring 36 is interposed between the diaphragm 34 and the inner wall of the container in the first chamber 31a. Room 31
b, pipes 5b and 5c are connected in a communicating state;
A nozzle 40 provided at the end of the conduit 5b opens into the second chamber 31b, and the diaphragm 34
A valve body 38 attached to the nozzle 40 is provided at a position facing the nozzle 40. and the first chamber 3
The opening area of the nozzle 40 is adjusted based on the pressure difference between the chambers 1a and 31b. That is, when the amount of heating in the high-temperature regenerator 2 is changed by the fuel control valve 26, the temperature and pressure of the solution in the high-temperature regenerator 2 and the amount of refrigerant generated change, and at the same time, the pressure inside the separator 4 changes. Furthermore, the amount of heat released in the condenser 8 and absorber 14 changes,
The heat radiation temperature of the cooling water changes. That is, separator 4
As the pressure inside the condenser 8 changes, the pressure inside the condenser 8 also changes. On the other hand, a coil 14a in the absorber 14,
When the temperature of the cooling water flowing through the coil 8a in the condenser 8 changes, the pressure in the condenser 8 changes, and at the same time, the pressure in the separator 4 also changes. This pressure change in the condenser 8 is transmitted to the first chamber 31a of the flow rate regulator 30 through the passage 33, whereby the valve body 38 is actuated together with the diaphragm 34 to increase the opening area of the nozzle 40. It's starting to change.

The action of the flow rate regulator 30 is shown in Fig. 1 when controlling the refrigerating capacity of a refrigerator in the range of 25% to 100%, and when the refrigerating capacity is constant but the temperature of the cooling water changes greatly. I will explain about it.

FIG. 3 is a diagram showing the relationship between the refrigerating capacity of the refrigerator and the pressure inside the separator 4. As is clear from this figure, the refrigerating capacity and the pressure inside the separator 4 (absolute pressure)
There is a proportional relationship. If the temperature of the cooling water is now constant at 32℃, if the refrigeration capacity is lowered from 100% to 25%, the pressure inside separator 4 will decrease from 650mmHg to 300mmHg.
It changes greatly to mmHg. The second of the flow regulator 30
The pressure inside the separator 4 (650 mmHg → 300
mmHg), while the pressure in the first chamber 31a is equal to the pressure in the condenser 8 due to the passage 33, and the pressure change in the condenser 8 is only a few mmHg. Therefore, the spring 36 acts to move the diaphragm 34 to the right in FIG. 2, and as a result, the valve body 3
The opening area formed by the nozzle 8 and the nozzle 40 is narrowed. At the same time, the flow control valve 24 also operates to narrow its opening area, and adjusts the solution circulation amount to a value suitable for the refrigeration capacity of 25%. As a result, refrigerant vapor generated in the separator 4 is prevented from entering the intermediate solution circuit constituted by the pipe 5a, the high temperature heat exchanger 18, and the pipes 5b and 5c.

FIG. 4 is a diagram showing the relationship between the temperature of the cooling water of the coils 8a and 14a and the pressure inside the condenser 8, and the temperature of the cooling water and the pressure inside the condenser are in a proportional relationship. If the temperature of the cooling water in the coils 8a and 14a drops from, for example, 34°C to 20°C while the refrigerating capacity is constant, the pressure in the condenser 8 will be 60 mmHg (absolute) as shown in Figure 4. pressure) to 28mmHg (absolute pressure). Therefore, the first
The pressure inside the chamber 31a decreases, and the diaphragm 34 moves to the left in FIG. 2 against the force of the spring 36. As a result, the opening area between the valve body 38 and the nozzle 40 is expanded, and the intermediate concentrated solution in the separator 4 can be smoothly supplied to the low-temperature regenerator 6. As a result, the intermediate concentrated solution does not accumulate in the separator 4, and there is no possibility that the refrigerant will freeze or the solution will crystallize due to concentration of the absorbed concentrated solution.

As described above, according to this embodiment, the opening area of the pipe line 5 is adjusted by using the flow rate regulator 30 according to the refrigerating capacity of the refrigerator or the temperature of the cooling water. The vapor refrigerant does not enter the intermediate concentrated solution supply circuit constituted by the high-temperature heat exchanger 18, and corrosion problems due to vapor entry do not occur. In addition, all the steam generated in the high temperature regenerator 2 and separator 4 is reliably transferred to the coil 6 in the low temperature regenerator.
Since the heat energy is sent to A, there is less loss of thermal energy and operational efficiency can be improved. Furthermore, since the intermediate concentrated solution can be smoothly supplied by the flow rate regulator 30, the problem of storing an excessive amount of intermediate concentrated solution in the separator 4 is eliminated. Further, even when the temperature of the cooling water is low, the absorbent concentrated solution is not excessively concentrated, so freezing of the refrigerant and crystallization of the solution can be prevented. Furthermore, the structure is very simple and manufacturing costs can be reduced.

〔effect〕

As is clear from the above description, according to the present invention, corrosion in the intermediate concentrated solution circuit can be reliably prevented, and operating efficiency can be improved by effectively utilizing thermal energy.

[Brief explanation of drawings]

Fig. 1 is a system diagram of an embodiment of the present invention, Fig. 2 is an explanatory diagram of the main part configuration of the invention, and Fig. 3 shows the relationship between the refrigerating capacity of the refrigerator and the pressure of the separator according to the present embodiment. 4 is a diagram showing the relationship between the cooling water temperature and the pressure inside the condenser, and FIG. 5 is a system diagram of a conventional dual-effect absorption refrigerator. 2...High temperature regenerator, 4...Separator, 6...Low temperature regenerator, 8...Condenser, 14...Absorber, 16...
... pump, 18 ... high temperature heat exchanger, 20 ... low temperature heat exchanger, 24 ... flow control valve, 30 ... flow regulator, 33 ... passage, 34 ... diaphragm, 3
6... Spring, 38... Valve body, 40... Nozzle.

Claims (1)

[Scope of utility model registration request] A high-temperature regenerator that heats a dilute solution that has absorbed refrigerant, a separator that separates the solution heated by the high-temperature regenerator into refrigerant vapor and an intermediate concentrated solution, and an intermediate concentrated solution separated by the separator. a low-temperature regenerator that is introduced after the temperature has been lowered and that heats and concentrates this intermediate concentrated solution using the refrigerant vapor obtained in the separator; and a condenser that condenses the refrigerant vapor that has been led through the low-temperature regenerator. an evaporator that evaporates the liquid refrigerant condensed in the condenser and exchanges heat with the load chilled water, and a concentrated solution obtained in the low-temperature regenerator is introduced, and the refrigerant vapor evaporated in the evaporator is converted into the concentrated solution. In a dual-effect absorption refrigerator in which an absorber that absorbs a solution and a pump that pumps the dilute solution obtained in this absorber to the high-temperature regenerator constitute one circulation system, A double-effect absorption refrigeration system, characterized in that a flow rate regulator is provided in the middle of the pipe for guiding the intermediate concentrated solution, the flow rate regulator adjusting the opening area in proportion to the pressure in the separation container and inversely proportional to the pressure in the condenser. Machine.