JP6814071B2 - Absorption chiller system and absorption chiller using waste heat - Google Patents

Description

The present invention relates to a waste heat utilization absorption chiller system and an absorption chiller.

Conventionally, an absorption chilling system using waste heat has been proposed, which comprises a power generation device that generates power and an absorption chiller that uses the waste heat of the power generation device to heat a dilute solution in a regenerator. Here, the power generation device is planned so that the power generation load is relatively constant. On the other hand, the absorption chiller is designed to operate according to the load. Therefore, when the load of the absorption chiller is small, it is not necessary to utilize all the waste heat from the power generation device. Therefore, the system described in Patent Document 1 has been proposed.

In the system described in Patent Document 1, when the load of the absorption chiller becomes small, the absorption liquid of the absorber is supplied to the evaporator together with the refrigerant to raise the evaporation temperature and lower the cooling capacity, thereby reducing the load. I try to drive.

Japanese Patent No. 3851764

However, in the waste heat utilization absorption refrigeration system described in Patent Document 1, since the absorption liquid is supplied to the evaporator, the amount of the absorption liquid regenerated in the regenerator is greatly reduced, and the regenerator It causes a large decrease in the amount of heat required for heating. Therefore, in the waste heat absorption chilling system described in Patent Document 1, if the above operation is continued, there is a possibility that the power generation device may be abnormally stopped.

In addition, in order to avoid the above-mentioned abnormal stop state, the pump is operated excessively in order to increase the amount of the absorbent liquid returned to the regenerator and the amount of the cooling water flowing through the absorber and the condenser. If forced, power consumption will increase.

Further, the waste heat absorption absorption refrigeration system described in Patent Document 1 has a state in which a liquid refrigerant is accumulated in the lower part of the evaporator, and this is sprayed again to the heat transfer tube of the evaporator by a pump. ing. For this reason, if the load becomes small and the absorbing liquid is sent into the evaporator, the absorbing liquid will be mixed in the accumulated liquid refrigerant, and when returning from the low load operation to the rated operation, the absorbing liquid is used. It takes a long time to discharge from the evaporator, and it becomes impossible to immediately return to the rated operation state.

The present invention has been made to solve such a conventional problem, and an object of the present invention is to reduce the possibility of an abnormal stop state of a power generation device and to consume power required to avoid the abnormal stop state. It is an object of the present invention to provide a waste heat utilization absorption chilling system and an absorption chiller capable of more smoothly returning to the rated operation while suppressing the amount.

The present invention includes a second path for guiding the concentrated solution obtained by heating in the regenerator to the absorber without spraying it on the absorption heat transfer tube, and the control valve is provided according to the temperature of the cooling target liquid sent out from the evaporation heat transfer tube. By adjusting the opening degree and controlling the ratio of the concentrated solution flowing through the first path and the second path, the absorption capacity of the refrigerant vapor in the absorber is controlled , and the flow through the third path from the absorber to the regenerator. It is characterized in that the amount of the absorbed liquid returned is kept constant regardless of the opening degree of the control valve .

According to the present invention, for example, when the load on the absorption chiller side becomes small and the change in load is detected as the temperature change of the liquid to be cooled, the amount of concentrated solution reaching the absorber through the second path is determined. By increasing the amount and reducing the amount of the concentrated solution sprayed on the absorption heat transfer tube of the absorber, the absorption capacity of the absorber can be reduced, and the evaporation in the evaporator can also be suppressed. Then, by suppressing evaporation, it becomes difficult for the cooling target liquid flowing through the evaporation heat transfer tube in the evaporator to be cooled, and low-load operation can be performed. Moreover, since the concentrated solution that reaches the absorber through the second path is returned to the regenerator, the amount of the absorbent liquid regenerated by the regenerator is maintained, and a large decrease in the amount of heat required for heating the regenerator is suppressed. It becomes. As a result, there is no need to take measures to increase the amount of power consumption, such as increasing the amount of absorbent liquid returned to the regenerator or increasing the amount of cooling water flowing through the absorber or condenser, and the power generation device. Can be prevented from becoming an abnormal stop state.

In addition, since the absorbent liquid is not sprayed by the evaporator, even if the evaporator adopts a circulation type configuration in which the liquid refrigerant is circulated, the absorbent liquid is discharged from the liquid refrigerant when returning to the rated operation. It is also possible to prevent it from taking too long to discharge.

Therefore, it is possible to return to the rated operation more smoothly while reducing the possibility of the abnormal stop state of the power generation device and suppressing the power consumption required for avoiding the abnormal stop state.

According to the present invention, it is possible to more smoothly return to the rated operation while reducing the possibility of the abnormal stop state of the power generation device and suppressing the power consumption required for avoiding the abnormal stop state.

It is a schematic block diagram of the waste heat utilization absorption type refrigeration system which concerns on embodiment of this invention. It is a flowchart which shows the process of the control panel of the waste heat absorption type refrigeration system which concerns on this embodiment.

Hereinafter, the present invention will be described with reference to preferred embodiments. The present invention is not limited to the embodiments shown below, and can be appropriately modified without departing from the spirit of the present invention. Further, in the embodiments shown below, some parts of the configuration are omitted from the illustration and description, but the details of the omitted technology are within a range that does not cause any contradiction with the contents described below. Needless to say, publicly known or well-known techniques are appropriately applied.

FIG. 1 is a schematic configuration diagram of a waste heat absorption chilling system according to an embodiment of the present invention. As shown in FIG. 1, the waste heat utilization absorption chiller system 1 according to the present embodiment includes a power generation device 10, an absorption chiller 20, and a connecting device 30.

The power generation device 10 generates power, and is composed of, for example, a device in which an engine 11 and a generator 12 are combined. In the power generation device 10, the engine 11 operates to operate the generator 12 to generate electricity. The engine 11 is a water-cooled type that is cooled by water (liquid), and the heat generated by the engine 11 is removed by the cooling water. In the present embodiment, the power generation device 10 is not limited to a device in which the engine 11 and the generator 12 are combined, and may be another power generation device such as a fuel cell as long as it is a water-cooled device.

The absorption chiller 20 includes a regenerator 21, a condenser 22, an evaporator 23, and an absorber 24, and cools the cooling target liquid flowing through the evaporation heat transfer tube 23a in the evaporator 23 by a circulation cycle by these. .. Further, the absorption chiller 20 includes the first to third pumps P1 to P3, a cooling tower CT, a pipe 23b for the liquid to be cooled, a pipe 23c for returning the liquid to be cooled, and a concentrated solution pipe (first path) 25. And a heat exchanger 26. Hereinafter, the absorption chiller 20 will be described in detail.

The regenerator 21 contains, for example, water as a refrigerant (hereinafter, vaporized refrigerant is referred to as refrigerant vapor, and liquefied refrigerant is referred to as liquid refrigerant) and lithium bromide (LiBr) as an absorbing liquid. It heats a mixed dilute solution (a solution with a low concentration of absorption liquid). The regenerator 21 releases the refrigerant vapor from the dilute solution by this heating, and produces the refrigerant vapor and a concentrated solution (a solution having a high concentration of the absorbing liquid).

The condenser 22 liquefies the refrigerant vapor supplied from the regenerator 21. A condensed heat transfer tube 22a is inserted into the condenser 22. Cooling water (cooling liquid) is supplied to the condensed heat transfer tube 22a from the cooling tower CT by the power of the first pump P1, and the evaporated refrigerant vapor is cooled by the cooling water in the condensed heat transfer tube 22a and liquefied. Further, the liquid refrigerant liquefied in the condenser 22 is supplied to the evaporator 23.

The evaporator 23 evaporates the liquid refrigerant. An evaporation heat transfer tube 23a is provided in the evaporator 23. The evaporation heat transfer tube 23a is connected to, for example, the indoor unit IU via the cooling target liquid going pipe 23b and the cooling target liquid returning pipe 23c, and the cooling target liquid warmed by the cooling utilization by the indoor unit IU is the second pump. It is supplied by the power of P2. Further, the inside of the evaporator 23 is in a substantially vacuum state. Therefore, the evaporation temperature of water as a refrigerant is about 5 ° C. Therefore, the liquid refrigerant sprayed on the evaporation heat transfer tube 23a evaporates depending on the temperature of the evaporation heat transfer tube 23a. Further, the temperature of the cooling target liquid in the evaporation heat transfer tube 23a is deprived by the evaporation of the liquid refrigerant. As a result, the cooling target liquid of the evaporation heat transfer tube 23a is cooled and supplied to the indoor unit IU, and the indoor unit IU supplies cold air into the room by using the cooled cooling target liquid.

The absorber 24 absorbs the refrigerant evaporated in the evaporator 23. The concentrated solution from the regenerator 21 is supplied into the absorber 24 through the concentrated solution pipe 25. Further, an absorption heat transfer tube 24a is inserted through the absorber 24. The concentrated solution that has reached the regenerator 21 through the concentrated solution pipe 25 is sprayed on the absorption heat transfer tube 24a. As a result, the refrigerant vapor evaporated in the evaporator 23 is absorbed by the concentrated solution on the surface of the absorption heat transfer tube 24a, and a dilute solution is generated. Further, the cooling water from the cooling tower CT flows through the absorption heat transfer tube 24a, and the endothermic heat generated by the absorption of the refrigerant vapor of the concentrated solution is removed by the cooling water of the absorption heat transfer tube 24a. The absorption heat transfer tube 24a is connected to the condensation heat transfer tube 22a.

Further, in the present embodiment, the lower part of the evaporator 23 and the absorber 24 communicate with each other. Therefore, the dilute solution whose concentration has decreased due to the absorption of the refrigerant in the absorber 24 and the liquid refrigerant that could not be completely evaporated in the evaporator 23 are supplied to the regenerator 21 by the third pump P3.

Further, the heat exchanger 26 exchanges heat between the dilute solution and the liquid refrigerant supplied to the regenerator 21 by the third pump P3 and the concentrated solution supplied from the regenerator 21 to the absorber 24 by the concentrated solution pipe 25. Do.

The connection device 30 thermally connects the power generation device 10 and the absorption chiller 20 and includes an engine cooling pipe 31, a heat source water supply pipe 32, and a heat exchanger 33. The engine cooling pipe 31 is a pipe through which cooling water for cooling the engine 11 flows. The heat source water supply pipe 32 is a pipe that supplies heat source water to the regenerator 21 of the absorption chiller 20. The heat exchanger 33 cools the engine 11 and introduces the heated cooling water, and supplies the heat of the cooling water to the heat source water of the heat source water supply pipe 32. With such a configuration, the waste heat of the engine 11 is used for heating the dilute solution in the regenerator 21 of the absorption chiller 20.

Further, the connecting device 30 includes a fourth pump P4 and a first three-way valve V1. The fourth pump P4 is provided in the heat source water bound pipe 32a of the heat source water supply pipe 32, and serves as a power source for supplying the heat source water to the regenerator 21. The first three-way valve V1 is provided in the heat source water return pipe 32b of the heat source water supply pipe 32. The first three-way valve V1 passes through a route for supplying the heat source water returning from the regenerator 21 to the heat exchanger 33 and a bypass pipe 32c connected to the downstream side of the fourth pump P4 in the heat source water going pipe 32a. A route for returning the heat source water to the heat exchanger 33 can be selected.

Further, the waste heat absorption absorption chilling system 1 according to the present embodiment includes a second three-way valve V2 and a radiator R. The engine cooling pipe 31 is composed of a cooling water going pipe 31a and a cooling water return pipe 31b, and the second three-way valve V2 is provided on the cooling water return pipe 31b, and the cooling water returning from the heat exchanger 33 is provided. The route for supplying the radiator R to the radiator R and the route for returning the engine 11 to the engine 11 can be selected.

Here, the first and second three-way valves V1 and V2 and the radiator R are used, for example, during maintenance of the absorption chiller 20. At the time of maintenance, the waste heat of the engine 11 cannot be supplied to the absorption chiller 20. Therefore, the first three-way valve V1 selects a route for returning the heat source water discharged from the heat exchanger 33 to the heat exchanger 33 again via the bypass pipe 32c (normally, the other route is selected). Further, the second three-way valve V2 selects a route for supplying cooling water to the radiator R (normally, the other route is selected). As a result, maintenance of the absorption chiller 20 can be performed while avoiding abnormal stoppage of the engine 11. In addition, these configurations may be used other than at the time of maintenance.

Here, in the waste heat utilization absorption refrigeration system 1 according to the present embodiment, the power generation device 10 is planned so that the power generation load is relatively constant. On the other hand, the absorption chiller 20 is designed to operate according to the magnitude of the load. Therefore, when the load of the absorption chiller 20 is small, it is not necessary to utilize all the waste heat from the power generation device 10. On the other hand, the waste heat utilization absorption chilling system 1 according to the present embodiment further includes a concentrated solution bypass tube (second path) 27, a control valve 28, a temperature sensor (temperature detecting means) T, and a control panel (absorption). By providing the force control means) 29, the absorption capacity of the absorption chiller 20 is controlled, and the absorption chiller 20 is operated according to the load while supplying substantially the entire amount of waste heat to the absorption chiller 20. I'm trying to do it. At this time, it is basically unnecessary to use the radiator R in this embodiment. This point will be described below.

The concentrated solution bypass pipe 27 is a pipe having one end connected to the downstream side of the heat exchanger 26 of the concentrated solution pipe 25 and the other end of the absorber 24 located below the absorption heat transfer pipe 24a. That is, the concentrated solution reaching the absorber 24 through the concentrated solution bypass tube 27 is returned to the regenerator 21 by the third pump P3 without being sprayed on the absorption heat transfer tube 24a.

The control valve 28 is a valve provided on the concentrated solution bypass pipe 27 with an adjustable opening degree. Here, when the control valve 28 is fully opened (opening 100%), all of the concentrated solution from the regenerator 21 reaches the absorber 24 through the concentrated solution bypass pipe 27. On the other hand, when the control valve 28 is in the fully closed state (opening 0%), all the concentrated solution from the regenerator 21 is sprayed from the upper part of the absorber 24 to the absorption heat transfer tube 24a without passing through the concentrated solution bypass pipe 27. Will be done. Further, when the opening degree of the control valve 28 becomes 50%, the concentrated solution reaches the absorber 24 by half through both paths. In this way, the control valve 28 functions as adjusting the ratio of the concentrated solution flowing through both paths.

The temperature sensor T is provided on the pipe 23b for the cooling target liquid, and detects the temperature of the cooling target liquid sent from the evaporation heat transfer tube 23a in the evaporator 23 to the indoor unit IU. The control panel 29 controls the entire absorption chiller 20. In particular, in the present embodiment, the control panel 29 adjusts the opening degree of the control valve 28 according to the temperature detected by the temperature sensor T in the operating state of the absorption chiller 20. As a result, the control panel 29 controls the ratio of the concentrated solution reaching the absorber 24 via the concentrated solution bypass tube 27 and the concentrated solution reaching the absorber 24 via the concentrated solution bypass tube 27, and the absorber 24 controls the ratio. The absorption capacity of the refrigerant vapor will be controlled. Here, the concentrated solution absorbs the refrigerant vapor on the surface of the absorption heat transfer tube 24a. Therefore, by increasing the amount of the concentrated solution reaching the absorber 24 via the concentrated solution bypass tube 27, the absorbing power of the absorber 24 can be reduced, and the evaporation in the evaporator 23 can also be suppressed. As a result, it is difficult to lower the temperature of the liquid to be cooled, and low-load operation can be performed.

Specifically, when the temperature of the liquid to be cooled detected by the temperature sensor T becomes equal to or lower than the first predetermined temperature, the control panel 29 adjusts the opening degree of the control valve 28 to adjust the opening degree of the concentrated solution to flow through the concentrated solution bypass pipe 27. The amount of water is controlled to increase and the absorption capacity is reduced. On the other hand, when the temperature of the solution to be cooled detected by the temperature sensor T becomes equal to or higher than the second predetermined temperature (temperature equal to or higher than the first predetermined temperature), the control panel 29 adjusts the opening degree of the control valve 28 to absorb the temperature. The amount of the concentrated solution sprayed on the heat transfer tube 24a is controlled to increase to increase the absorption capacity. As a result, while keeping the temperature of the liquid to be cooled constant, the absorption capacity is changed to perform low load operation, rated operation, and the like.

In particular, in the present embodiment, unlike Patent Document 1, the amount of the absorbent liquid returned to the regenerator 21 does not decrease, so that the amount of the absorbent liquid regenerated by the regenerator 21 is maintained and the regenerator 21 is used. It is possible to suppress a large decrease in the amount of heat required for heating. As a result, it is possible to prevent the power generation device 10 from being in an abnormally stopped state.

In addition, since the amount of the absorbent liquid regenerated by the regenerator 21 is maintained, it is not necessary to take measures such as increasing the amount of the absorbent liquid returned to the regenerator 21 to increase the power consumption. Further, it is not necessary to take measures such as increasing the circulation amount of the cooling water.

Next, the operation of the waste heat absorption chilling system 1 according to the present embodiment will be described. FIG. 2 is a flowchart showing the processing of the control panel 29 of the waste heat absorption chilling system 1 according to the present embodiment. The process shown in FIG. 2 is repeatedly executed until the power of the absorption chiller 20 is turned off.

As shown in FIG. 2, the control panel 29 detects the temperature of the cooling target liquid sent from the evaporation heat transfer tube 23a to the indoor unit IU based on the signal from the temperature sensor T (S1). Next, the control panel 29 determines whether the temperature of the cooling target liquid detected in step S1 is equal to or lower than the first predetermined temperature (S2).

When it is determined that the temperature of the liquid to be cooled is equal to or lower than the first predetermined temperature (S2: YES), the control panel 29 increases the opening degree of the control valve 28 by a predetermined amount (S3). As a result, the control panel 29 increases the amount of the concentrated solution supplied to the absorber 24 without being sprayed on the absorption heat transfer tube 24a, and lowers the absorption capacity of the absorber 24. Then, the process shown in FIG. 2 is completed.

On the other hand, when it is determined that the temperature of the cooling target liquid is not equal to or lower than the first predetermined temperature (S2: NO), the control panel 29 determines whether the temperature of the cooling target liquid detected in step S1 is equal to or higher than the second predetermined temperature. (S4). When it is determined that the temperature of the liquid to be cooled is not equal to or higher than the second predetermined temperature (S4: NO), the process shown in FIG. 2 ends.

On the other hand, when it is determined that the temperature of the liquid to be cooled is equal to or higher than the second predetermined temperature (S4: YES), the control panel 29 reduces the opening degree of the control valve 28 by a predetermined amount (S5). As a result, the control panel 29 increases the amount of the concentrated solution sprayed on the absorption heat transfer tube 24a, and enhances the absorption capacity of the absorber 24. Then, the process shown in FIG. 2 is completed.

In this way, according to the waste heat utilization absorption chilling system 1 and the absorption chiller 20 according to the present embodiment, the concentrated solution obtained by heating in the regenerator 21 is absorbed without being sprayed on the absorption heat transfer tube 24a. A concentrated solution bypass pipe 27 leading to the vessel 24 is provided, and the opening degree of the control valve 28 is adjusted according to the temperature of the liquid to be cooled to flow through the concentrated solution bypass pipe 27 and the concentrated solution bypass pipe 27. By controlling the proportion of the concentrated solution flowing, the absorption capacity of the refrigerant vapor in the absorber 24 is controlled.

Therefore, for example, when the load on the absorption chiller 20 side becomes small and the change in load is detected as the temperature change of the liquid to be cooled, the amount of concentrated solution reaching the absorber 24 through the concentrated solution bypass pipe 27. By increasing the amount of the concentrated solution sprayed on the absorption heat transfer tube 24a of the absorber 24, the absorption capacity of the absorber 24 can be reduced, and the evaporation in the evaporator 23 can also be suppressed. Then, by suppressing evaporation, it becomes difficult for the cooling target liquid flowing through the evaporation heat transfer tube 23a in the evaporator 23 to be cooled, and a low load operation can be performed. Moreover, since the concentrated solution that has reached the absorber 24 through the concentrated solution bypass tube 27 is returned to the regenerator 21, the amount of the absorbent liquid regenerated by the regenerator 21 is maintained, and the amount of heat required for heating the regenerator 21 is maintained. Will suppress a large decrease in. As a result, it is not necessary to take measures such as increasing the amount of the absorbent liquid returned to the regenerator 21 or increasing the amount of cooling water flowing through the absorber 24 and the condenser 22 to increase the power consumption. , It is possible to prevent the power generation device 10 from being abnormally stopped.

Further, since the absorbing liquid is not sprayed by the evaporator 23, even if the evaporator 23 adopts a circulation type configuration in which the liquid refrigerant is circulated, it is absorbed from the liquid refrigerant when returning to the rated operation. It is also possible to prevent the liquid from taking too long to be discharged.

Therefore, it is possible to return to the rated operation more smoothly while reducing the possibility of the abnormal stop state of the power generation device 10 and suppressing the power consumption required for avoiding the abnormal stop state.

Further, when the temperature of the liquid to be cooled becomes equal to or lower than the first predetermined temperature, the amount of the concentrated solution flowing through the concentrated solution bypass tube 27 is controlled to increase to reduce the absorbing power of the absorber 24, so that the evaporator Evaporation in No. 23 is suppressed, and the temperature of the solution to be cooled is raised. On the other hand, when the temperature of the liquid to be cooled becomes equal to or higher than the second predetermined temperature, evaporation is performed in order to increase the absorption capacity of the absorber 24 by controlling the amount of the concentrated solution not via the concentrated solution bypass tube 27 to increase. The evaporation in the vessel 23 is increased, and the temperature of the solution to be cooled is lowered. In this way, low-load operation, rated operation, and the like can be performed while keeping the temperature of the liquid to be cooled constant.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the above-described embodiments, and changes may be made without departing from the spirit of the present invention, and other examples may be made as appropriate. Techniques may be combined.

For example, in the waste heat absorption chilling system 1 according to the present embodiment, the cooling water of the engine 11 is heat-exchanged with the heat source water, but the present invention is not limited to this, and the exhaust gas from the engine 11 is further heat-exchanged with the heat source water. You may do so.

Further, in the above embodiment, an absorption chiller-heater may be used as long as it has the function of the absorption chiller 20.

1: Absorption chiller system using waste heat 10: Power generation device 11: Engine 12: Generator 20: Absorption chiller 21: Regenerator 22: Condenser 22a: Condensation heat transfer tube 23: Evaporator 23a: Evaporation heat transfer tube 23b: Cooling target liquid going pipe 23c: Cooling target liquid return pipe 24: Absorber 24a: Absorption heat transfer pipe 25: Concentrated solution pipe (first path)
26: Heat exchanger 27: Concentrated solution bypass tube (second path)
28: Control valve 29: Control panel (absorption force control means)
30: Connection equipment 31: Engine cooling pipe 31a: Cooling water bound pipe 31b: Cooling water return pipe 32: Heat source water supply pipe 32a: Heat source water bound pipe 32b: Heat source water return pipe 32c: Bypass pipe 33: Heat exchanger CT: Cooling tower IU: Indoor unit P1 to P4: Pump R: Radiator T: Temperature sensor (temperature detecting means)
V1, V2: Three-way valve

Claims (3)

A power generation device that generates power and is cooled by a liquid, and an absorption chiller that cools the liquid to be cooled flowing through the evaporation heat transfer tube in the evaporator by a circulation cycle of a regenerator, a condenser, an evaporator, and an absorber. A waste heat absorption chilling system that heats a rare solution in the regenerator using a liquid that has been heated by cooling the power generation device.
The absorption chiller
A first path for guiding the concentrated solution obtained by heating in the regenerator to the absorber and spraying it on the absorption heat transfer tube through which the coolant flows in the absorber.
A second path that guides the concentrated solution obtained by heating in the regenerator to the absorber without spraying it on the absorption heat transfer tube.
A temperature detecting means for detecting the temperature of the liquid to be cooled sent from the evaporation heat transfer tube in the evaporator, and a temperature detecting means.
A control valve for adjusting the ratio of the concentrated solution flowing through the first path and the second path, and
In the operating state in which the dilute solution is heated by the regenerator, the opening degree of the control valve is adjusted according to the temperature of the cooling target liquid detected by the temperature detecting means, and the first path and the second path Absorption power control means for controlling the absorption power of the refrigerant vapor in the absorber by controlling the ratio of the concentrated solution flowing through the absorber.
A third path that guides the absorbent solution from the absorber to the regenerator,
In the operating state in which the dilute solution is heated by the regenerator, the amount of the absorbing liquid flowing through the third path and returned from the absorber to the regenerator is maintained constant regardless of the opening degree of the control valve. A waste heat absorption absorption refrigeration system characterized by being provided with an absorption liquid return amount control means . When the temperature of the cooling target liquid detected by the temperature detecting means becomes equal to or lower than the first predetermined temperature, the absorbing power controlling means adjusts the opening degree of the control valve to adjust the opening degree of the concentrated solution flowing through the second path. The control valve is controlled so that the amount is increased to reduce the absorption capacity, and when the temperature of the cooling target liquid detected by the temperature detecting means becomes equal to or higher than the first predetermined temperature or higher than the second predetermined temperature. The waste heat utilization absorption type refrigeration system according to claim 1, wherein the opening degree of the system is adjusted so that the amount of the concentrated solution flowing through the first path is controlled to increase the absorption capacity. Absorption that cools the liquid to be cooled flowing through the evaporation heat transfer tube in the evaporator by a circulation cycle by the regenerator, the condenser, the evaporator, and the absorber, and heats the dilute solution in the regenerator using the heat source water. It is a type refrigerator
A first path for guiding the concentrated solution obtained by heating in the regenerator to the absorber and spraying it on the absorption heat transfer tube through which the coolant flows in the absorber.
A second path that guides the concentrated solution obtained by heating in the regenerator to the absorber without spraying it on the absorption heat transfer tube.
A temperature detecting means for detecting the temperature of the liquid to be cooled sent from the evaporation heat transfer tube in the evaporator, and a temperature detecting means.
A control valve for adjusting the ratio of the concentrated solution flowing through the first path and the second path, and
In the operating state in which the dilute solution is heated by the regenerator, the opening degree of the control valve is adjusted according to the temperature of the cooling target liquid detected by the temperature detecting means, and the first path and the second path Absorption power control means for controlling the absorption power of the refrigerant vapor in the absorber by controlling the ratio of the concentrated solution flowing through the absorber.
A third path that guides the absorbent solution from the absorber to the regenerator,
In the operating state in which the dilute solution is heated by the regenerator, the amount of the absorbing liquid flowing through the third path and returned from the absorber to the regenerator is maintained constant regardless of the opening degree of the control valve. An absorption chiller characterized by being provided with an absorption liquid return amount control means .

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