JPH0854153A - Single and double effect absorption type refrigerating machine - Google Patents

Abstract

PURPOSE:To prevent condensating even when the cooling water of a generator is employed for a low-temperature heat source supplied to a low heat source regenerator and contrive the simplification of control of supplying amount of the low temperature heat source. CONSTITUTION:Circulation passages of absorbing liquid and refrigerant are formed by connecting an evaporator 1, an absorber 2, a low-temperature regenerator 6, a condenser 7, a low heat source regenerator 9 employing hot waste water and the like as a low temperature heat source, another condenser 10 and a high temperature regenerator 4 through pipelines while a three-way valve 29E is provided so as to communicate the supplying tube of a low-temperature heat source with the returning tube of the same. The heating amount of the high-temperature regenerator 4 is controlled based on the outlet temperature of cold water, taken out of the evaporator 1, while the three-way valve 29E is controlled based on the outlet temperature of the cold water. Controllers 30, 36, 38, increasing the set valve of the outlet temperature of the cold water for controlling the three-way valve when the returning temperature of the low-temperature heat source has become a predetermined temperature or less, are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption refrigerating machine, and more particularly to a single-effect double-effect absorption refrigerating machine having a low heat source regenerator condenser barrel containing a low heat source regenerator and a condenser.

[0002]

2. Description of the Related Art For example, in Japanese Unexamined Patent Publication (Kokai) No. 4-260760, an evaporator absorber body containing an evaporator and an absorber, a low temperature regenerator condenser body containing a low temperature regenerator and a condenser, and Low heat source regenerator that uses low temperature heat source such as waste water and a low heat source regenerator that contains a condenser. A single double-effect absorption type in which a condenser body and a high temperature regenerator are connected by piping to form a circulation path for absorbing liquid and refrigerant. A refrigerator is disclosed.

Further, as a control method of a single-double-effect absorption refrigerator, there is, for example, Japanese Patent Application No. 5-130686. These controls are for keeping the outlet temperature of the cold water taken out from the evaporator constant. For this reason, the temperature of the low-temperature heat source returning from the low heat source regenerator tends to decrease as the cold water load increases. Therefore, for example, when using cooling water such as a generator as a low-temperature heat source, if the temperature of the low-temperature heat source returning to the generator drops significantly,
Condensation may occur and the generator may be in trouble. Therefore, as shown in FIG. 5, the temperature sensor S1, the controller C1, and the flow rate control valve (three-way valve) 29E are provided to control the flow rate to the low heat source heat exchanger 29B according to the chilled water outlet temperature. A temperature sensor S5, a controller C4, and a flow control valve (three-way valve) 29F are provided so that the return temperature of the low temperature heat source is constant on the equipment side, and the low heat source supply pipe 29A supplies the low heat source heat exchanger 29B. It is controlled so that the return temperature of the low-temperature heat source that radiates heat therethrough and returns through the low-heat-source return pipe 29C is constant.

In FIG. 5, 1 is an evaporator, 2 is an absorber, 4 is a high temperature regenerator, 6 is a low temperature regenerator, 9 is a low heat source regenerator, 7 and 10 are condensers, and 12 is a low temperature heat exchange. , 13 is a high temperature heat exchanger, P1 is a rare absorption liquid pump, P2 is an intermediate absorption liquid pump, P3 is a refrigerant liquid pump, C1, C2, C
3 and C4 are controllers.

[0005]

In the conventional single-double-effect absorption type refrigerator as described above, two expensive valves such as a three-way valve are required in order to control the supply amount of the low temperature heat source. However, the solution to this problem has been an issue from the viewpoint of cost reduction.

[0006]

In order to solve the above-mentioned problems, the present invention provides, according to the invention as set forth in claim 1, an evaporator-absorber barrel containing an evaporator and an absorber, and a low-temperature regenerator. Low temperature regenerator containing a condenser and a low heat source regenerator containing a condenser body and a low heat source regenerator that uses hot waste water as a low temperature heat source And, forming a circulation path of the refrigerant, a three-way valve is provided so as to connect the supply pipe and the return pipe of the low temperature heat source, and while controlling the heating amount of the high temperature regenerator based on the outlet temperature of the cold water taken out from the evaporator, The three-way valve is controlled based on the outlet temperature of the cold water, and when the return temperature of the low temperature heat source falls below a predetermined temperature,
It is intended to provide a single-effect double-effect absorption refrigerator provided with a controller for increasing a set value of a cold water outlet temperature for controlling a three-way valve.

Further, according to the invention described in claim 2, an evaporator absorber body containing an evaporator and an absorber, a low temperature regenerator condenser body containing a low temperature regenerator and a condenser, and Low-heat-source regenerator that uses a low-temperature heat source such as waste water and a low-heat-source regenerator that houses a condenser, connecting the condenser body and the high-temperature regenerator to form a circulation path for absorbing liquid and refrigerant, and supplying a low-temperature heat source A three-way valve is provided so as to connect the return pipe and the return pipe, and the heating amount of the high temperature regenerator is controlled based on the outlet temperature of the cold water taken out from the evaporator, and the three-way valve is controlled based on the outlet temperature of the cold water, and Provided is a single-effect double-effect absorption refrigerator having a controller for gradually increasing the set value of the cold water outlet temperature for controlling the three-way valve as the return temperature of the low temperature heat source decreases below a predetermined temperature.

Further, according to the invention described in claim 3, an evaporator-absorber cylinder containing an evaporator and an absorber, a low-temperature regenerator condenser cylinder containing a low-temperature regenerator and a condenser, and Low-heat-source regenerator that uses a low-temperature heat source such as waste water and a low-heat-source regenerator that houses a condenser, connecting the condenser body and the high-temperature regenerator to form a circulation path for absorbing liquid and refrigerant, and supplying a low-temperature heat source A three-way valve is provided so as to connect the return pipe and the return pipe, and the heating amount of the high temperature regenerator is controlled based on the outlet temperature of the cold water taken out from the evaporator, and the three-way valve is controlled based on the outlet temperature of the cold water, and When a return temperature of the low temperature heat source is lower than a predetermined temperature, a single double-effect absorption refrigerator provided with a controller for reducing the amount of the low temperature heat source flowing into the low temperature heat source regenerator with the decrease Is.

[0009]

According to the invention of claim 1, since the heating amount of the high temperature regenerator and the three-way valve are controlled based on the outlet temperature of the cold water taken out from the evaporator, the responsiveness to load fluctuation can be improved and the low heat source regeneration The outlet temperature of the cold water can be maintained at the set value regardless of increase / decrease of the low temperature heat source supplied to the vessel and fluctuation of the load.

Further, when the return temperature of the low temperature heat source is lowered due to a change in load or the like, the set value of the outlet temperature of the cold water is increased and the amount of the low temperature heat source flowing into the low temperature heat source regenerator is decreased to return the low temperature heat source. Even if the cooling water of the generator can be used as a low temperature heat source, the temperature can be maintained above the specified temperature. Can be avoided.

Further, such an excellent effect can be obtained by operating a single three-way valve, and it is possible to provide a single-double-effect absorption refrigerating machine which is also excellent in cost. . Further, according to the invention of claim 2, when the return temperature of the low temperature heat source is lowered, the amount of the low temperature heat source flowing into the low temperature heat source regenerator is gradually reduced according to the degree of the reduction, and the discharge in the low temperature heat source regenerator is reduced. Gradually reduce the amount of heat,
The responsiveness to load fluctuations can be improved, the return temperature of the low-temperature heat source can be maintained above the specified temperature, and the return temperature of the low-temperature heat source decreases when the generator cooling water is used as the low-temperature heat source. Even in such a case, it is possible to avoid the trouble that dew condensation occurs when the generator is cooled by the low temperature heat source whose temperature has dropped significantly while effectively using the low temperature heat source.

Further, it is possible to prevent the regeneration temperature of the low heat source regenerator from being extremely lowered, and even when the heat quantity of the low temperature heat source changes, the heat of the low temperature heat source is more effectively utilized, and the regeneration of the refrigerant is effective. It is possible to improve COP. According to the invention of claim 3, the heating amount of the high temperature regenerator and the three-way valve are controlled based on the outlet temperature of the cold water taken out from the evaporator, and when the return temperature of the low temperature heat source is lower than a predetermined temperature, With this decrease, the amount of the low temperature heat source flowing into the low temperature heat source regenerator is reduced, and the outlet temperature of the cold water is maintained at the set value regardless of the fluctuation of the low temperature heat source supplied to the low heat source regenerator and the load. It becomes possible to improve the responsiveness to load fluctuations, and when the return temperature of the low temperature heat source decreases, the amount of low temperature heat source flowing into the low temperature heat source regenerator is reduced to reduce the amount of heat released by the low temperature heat source regenerator. Can be maintained and the return temperature of the low temperature heat source can be maintained above a predetermined temperature, and even when cooling water of the generator is used as the low temperature heat source, the generator is cooled by the low temperature heat source whose temperature has dropped significantly. Condensation when doing It becomes possible to avoid the trouble, such as say that.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows that the refrigerant is, for example, water or an absorbing liquid (solution)
FIG. 1 is a schematic configuration diagram of a single-double-effect absorption refrigerating machine using a lithium bromide (LiBr) solution as a solvent. 1 is an evaporator, 2 is an absorber, 3 is an evaporator containing an evaporator 1 and an absorber 2. An absorber cylinder (hereinafter, referred to as a lower cylinder) 4, a high temperature regenerator which is equipped with a gas burner 5 and is heated by a high temperature heat source, 5A is a fuel control valve for adjusting the amount of gas supplied to the gas burner 5, and 6 is a low temperature A regenerator, 7 is a condenser for the low-temperature regenerator 6 (hereinafter, referred to as a first condenser), 8 is a low-temperature regenerator condenser cylinder (hereinafter, referred to as a first condenser) accommodating the low-temperature regenerator 6 and the first condenser 7. 1
Upper body), 9 is a low heat source regenerator which uses warm wastewater of around 95 ° C. as a low temperature heat source, 10 is a condenser for the low temperature heat source regenerator 9 (hereinafter referred to as a second condenser), and 11 is A low heat source regenerator condenser barrel (hereinafter, referred to as a second upper barrel) accommodating the low heat source regenerator 9 and the second condenser 10, 12 is a low temperature heat exchanger,
13 is a high temperature heat exchanger.

Reference numeral 2A denotes a rare absorbent pool formed in the lower portion of the absorber 2, and the rare absorbent pool 2A and the low heat source regenerator 9 are provided.
The gas phase part is connected by a dilute absorption liquid pipe 14 equipped with a dilute absorption liquid pump P1 on the way. Further, the intermediate absorbent pool 9A formed in the lower part of the low heat source regenerator 9 and the gas phase portion of the high temperature regenerator 4 are connected to the intermediate absorbent pump P2 midway.
The pipe is connected by an intermediate absorption liquid pipe 15 provided with.

Reference numeral 4A denotes an intermediate absorption liquid pool formed in the high temperature regenerator 4, and the intermediate absorption liquid pool 4A and the low temperature regenerator 6 are provided.
The gas phase portion is connected to the gas phase portion by an intermediate absorption liquid pipe 16. Further, the concentrated absorbent pool 6A formed in the lower portion of the low temperature regenerator 6 and the concentrated absorbent spraying device 2B provided in the gas phase part of the absorber 2 are concentrated absorbent pipes composed of concentrated absorbent pipes 17A and 17B. It is connected by pipes by 17.

An intermediate absorption liquid pipe 15A on the suction side of the intermediate absorption liquid pump P2 and a concentrated absorption liquid pipe 17A on the upstream side of the low temperature heat exchanger 12 are connected by an absorption liquid pipe 18. The absorbing liquid pipe 18 is provided at a position lower than that of the first upper body 8, and even if there is a difference between the pressure in the second upper body 11 and the pressure in the first upper body 8, the distance between the respective bodies is increased. Is U-sealed by the absorbent.

Further, the intermediate absorption liquid pipe 16A on the upstream side of the high temperature heat exchanger 13 and the absorber 2 are connected by an intermediate absorption liquid pipe 19 having an opening / closing valve 10V in the middle thereof.
The on-off valve 19V is closed when cold water is supplied and opened when hot water is supplied. Reference numeral 20 denotes a refrigerant vapor pipe extending from the gas phase portion of the high temperature regenerator 4 to the first upper body 8, and opens at the bottom of the first condenser 7 via the inside of the low temperature regenerator 6. 21
Is a refrigerant vapor pipe that is provided with an on-off valve 21V on the way and connects the refrigerant vapor pipe 21A on the upstream side of the low temperature regenerator 6 and the vapor phase portion of the absorber 2. The on-off valve 21V is closed when cold water is supplied and opened when hot water is supplied.

Reference numeral 22 is a first refrigerant liquid pipe for connecting the bottom portion of the first condenser 7 and the vapor phase portion of the evaporator 1 by piping.
A U-seal portion 22A is formed in the middle of the refrigerant liquid pipe 22. Reference numeral 23 is a second refrigerant liquid pipe that connects the bottom portion of the second condenser 10 and the U-seal portion 22A of the first refrigerant liquid pipe 22 to the second refrigerant liquid pipe 23. A U-seal portion 23A is formed at a connection portion with 22.

Reference numeral 24 denotes a refrigerant liquid circulation pipe for connecting the refrigerant liquid reservoir 1A of the evaporator 1 and the refrigerant spraying device 1B, and a refrigerant liquid pump P3 is provided in the middle of the refrigerant liquid circulation pipe 24. Reference numeral 25 denotes a refrigerant liquid drain pipe connected between the refrigerant liquid reservoir 1A and the rare absorption liquid reservoir 2A, and an opening / closing valve 25V is provided in the refrigerant liquid drain pipe 25.

Reference numeral 26 is a cold / hot water pipe, and this cold / hot water pipe pipe 26 is composed of a cold / hot water pipe 26A, an evaporator heat exchanger 26B, and a cold / hot water pipe 26C. 27 is a cooling water pipe, and this cooling water pipe 27 passes from a cooling tower (not shown) through the absorber heat exchanger 27A, the first condenser heat exchanger 27B, and the second condenser heat exchanger 27C. A cooling water circulation path is formed. Further, 28 is the first condenser heat exchanger 2
Cooling water pipe 27 from 7B to the second condenser heat exchanger 27C
D is a cooling water pipe connected between the hot and cold water pipe 26, and an opening / closing valve 28V is provided in the middle of the cooling water pipe 28. The on-off valve 28V is opened when hot water is supplied,
Water is sent from the cold / hot water pipe 26C to the cooling water pipe 27 and stored.

Reference numeral 29 is a low heat source supply pipe for supplying warm waste water of about 95 ° C., for example, cooling water of a generator (not shown) as a low temperature heat source (hereinafter referred to as heat source hot water) to the low heat source regenerator 9. . The low heat source supply pipe 29 includes a low heat source supply pipe 29A, a low heat source heat exchanger 29B, a low heat source return pipe 29C, a bypass pipe 29D, and a three-way valve 29E.

Reference numeral 30 is a main controller, 31, 32, 33,
34 and 35 are temperature sensors, and the temperature sensor 31
Is the temperature T1 of the cold / hot water flowing through the hot / cold water pipe 26C, the temperature sensor 32 is the temperature T2 of the cooling water flowing into the absorber 2, and the temperature detector 33 is the temperature of the solution in the high temperature regenerator 4. The temperature detector 34 detects T3, the temperature detector 34 detects the temperature T4 of the intermediate absorption liquid flowing out from the low heat source regenerator 9 to the intermediate absorption liquid pipe 15, and the temperature sensor 35 detects the return temperature T5 of the heat source hot water. Further, the main controller 30 controls the temperature T1 of the cold / hot water detected by the temperature sensor 31 to the controllers 36, 3
Give to 7, 38.

The controller 36 controls the opening degree of the fuel control valve 5A based on the temperature of the cold / hot water obtained from the main controller 30, and compares, for example, the cold water temperature T1 with the set temperature of 7.0 ° C., for example. When the cold water temperature T1 is lower than the set temperature, a close signal is output to the fuel control valve 5A, and the opening degree of the fuel control valve 5A gradually decreases. When the cold water temperature T1 is higher than the set temperature, a close signal is output to the fuel control valve 5A, and the opening degree of the fuel control valve 5A gradually increases. The flow rate of gas supplied to the gas burner 5 changes as the opening of the fuel control valve 5A changes.

Further, the controller 36 controls the start / stop of the intermediate absorbent pump P2 based on the temperature of the cold / hot water obtained from the main controller 30, and further the temperature T2 of the cooling water detected by the temperature sensor 32. And the temperature T3 of the solution in the high temperature regenerator 4 detected by the temperature sensor 33, the frequency of the electric power supplied to the intermediate absorption liquid pump P2 is controlled. Then, the power of the frequency controlled by the controller 36 is supplied from the frequency converter 40 to the intermediate absorbent pump P2,
The rotation speed of the intermediate absorption liquid pump P2 is controlled.

The controller 37 instructs the rated operation of the diluted absorbent pump P1 based on the temperature T1 of the cold / hot water obtained from the main controller 30, and when the rated operation is not instructed, the temperature sensor 34 detects it. Intermediate absorption liquid temperature T4
The frequency of the electric power supplied to the diluted absorbent pump P1 is controlled based on the above. Then, the electric power of the frequency controlled by the controller 37 is supplied from the frequency converter 41 to the diluted absorbent pump P1.
And the rotational speed of the diluted absorbent pump P1 is controlled.

The controller 38 is a controller for controlling the opening of the flow control valve 29E. The controller 38 compares the temperature T1 of the cold / warm water obtained from the main controller 30 with the set temperature to control the flow rate. An open / close signal is output to the valve 29E, and the low heat source return pipe 2
The flow rate of the heat source hot water flowing back through 9C is controlled. Here, for example, when supplying cold water, the detected cold water temperature T1
And the set temperature of, for example, 6.5 ° C. are compared, and the flow control valve 2
Open / close signal is output to 9E. Further, the controller 38 changes the set temperature based on the return temperature T5 of the heat source hot water detected by the temperature sensor 35. For example, at the time of supplying the cold water, based on the cold water temperature T1 as shown by the solid line in FIG. The set temperature changes.

In the absorption refrigerating machine constructed as described above, the control at the time of supplying cold water to the load by closing the on-off valves 19V, 21V, 25V and 28V and supplying cold water to the load through the hot / cold water pipe 26C will be described. First, the temperature T1 of the cold water detected by the temperature sensor 34 is given from the main controller 30 to the controllers 36, 37 and 38.

The controller 36 controls the opening degree of the fuel control valve 5A based on the temperature T1 of the cold water, and controls the amount of gas supplied to the gas burner 5. Further, the heat source hot water supplied from the low heat source supply pipe 29 to the low heat source regenerator 9 controls the opening degree of the flow rate control valve 29E based on the temperature T1 of the cold water sent from the main controller 30 by the controller 38, Low heat source heat exchanger 29
The heat source hot water flow rate flowing to the E side is controlled. Therefore, the heating amount of the high temperature regenerator 4 increases and decreases as the heat amount of the heat source hot water increases and decreases, and the shortage amount of the heat source hot water is compensated by the high temperature regenerator 4.
From the low heat source supply pipe 29 to the low heat source regenerator 9 of the second upper body 11
The temperature T1 of the supplied cold water can be maintained at the set value regardless of the heat quantity of the heat source hot water supplied to the.

Further, in the controller 38, as shown in FIG. 2, the set value of the cold water temperature changes according to the return temperature T5 of the heat source hot water returning to the heat source through the low heat source return pipe 29C,
When the return temperature T5 of the heat source hot water falls below 82.5 ° C., for example, the set value of the cold water temperature gradually rises as the return temperature T5 falls. Even when the set value in the controller 38 becomes high, the heating amount of the high temperature regenerator 4 is controlled according to the temperature T1 of the cold water as described above, so that the temperature T1 of the cold water is almost the set temperature. Maintained at 7 ° C. When the temperature T1 of the cold water is substantially constant and the set value of the cold water temperature in the controller 38 rises, the controller 38 outputs a signal to the flow control valve 29E. Therefore, the opening degree of the flow control valve 29E on the low heat source heat exchanger 29B side is reduced, and the three-way valve heat source supply pipe 29
Amount of heat source hot water supplied to the low heat source regenerator 9 from
The opening degree of the bypass pipe 29D increases, the amount of heat source hot water supplied from the low heat source supply pipe 29A and flowing to the bypass pipe 29D increases, and the return temperature T5 rises.

Hereinafter, the case where a sufficient amount of heat is obtained from the heat source hot water with respect to the cold water load in the low temperature heat source regenerator 9 of the second upper case 11 and the case where an adequate amount of heat is not obtained are divided into specific cases. Another control example will be described. For example, when a sufficient amount of heat is obtained for the cold water load from the heat source hot water flowing from the heat source, the controller 38 determines the flow rate control valve 29E based on the temperature T1 of the cold water sent from the main controller 30. Control the opening of. Then, the amount of the heat source hot water flowing through the low heat source heat exchanger 29B changes according to the temperature of the cold water, whereby the temperature T1 of the cold water supplied to the load via the cold / hot water pipe 26C is maintained at the set temperature.

Therefore, when a sufficient amount of heat is obtained for the cold water load from the heat source hot water flowing through the low heat source supply pipe 29, the temperature of the cold water supplied to the load is for controlling the heating amount of the high temperature regenerator 4. It is lower than the set temperature of 7 ° C., for example. Therefore, the controller 36 does not control the fuel control valve 5A, the fuel control valve 5A remains closed, the gas burner 5 does not burn, and the high temperature regenerator 4 is stopped. Further, the controller 36 does not output a start signal to the intermediate absorbent pump P2, and the intermediate absorbent pump P2 is stopped.

The controller 37 determines that the temperature T1 of the cold water is equal to that of the controller 3
Main controller 30 when the temperature is lower than 7 ° C which is the set value of 6
The operation of the rare absorbent pump P1 is not controlled on the basis of the temperature signal from the above, but the frequency of the electric power supplied to the rare absorbent pump P1 is determined based on the temperature T4 of the intermediate absorbent detected by the temperature sensor 34. For example, control is performed as shown in FIG. 3 to control the rotation speed of the diluted absorbent pump P1.

For example, when the temperature of the intermediate absorption liquid is 80 ° C. or higher, the rare absorption liquid pump P1 is rated at 60.
When the temperature is 70 ° C. or lower, for example, the frequency is 30 Hz, which is half the rated frequency. Further, when the temperature of the intermediate absorption liquid is between 70 and 80 ° C., the operation is performed at a frequency proportional to the temperature, for example. For this reason, when the load is small, the amount of refrigerant regenerated is small, and the regeneration temperature is low, the circulation amount of the rare absorption liquid is reduced, sensible heat loss is reduced, and COP of the absorption chiller is improved.

The circulation of the refrigerant and the solution will be described below. The circulation of the refrigerant and the solution is the same as the circulation of the conventional single-double-effect absorption refrigerator, it is a cold water supply operation, and if a sufficient amount of heat is obtained from the heat source hot water to the cold water load, The absorption liquid pump P2 and the high temperature regenerator 4 are stopped, and the intermediate absorption liquid whose concentration has increased by evaporating and separating the refrigerant in the low temperature heat source regenerator 9 is the intermediate absorption liquid pipe 15A and the absorption liquid pipe 1
8, the concentrated absorbent liquid pipe 17A, the low temperature heat exchanger 12, and the concentrated absorbent liquid pipe 17B are sprayed from the concentrated absorbent liquid spraying device 2B of the absorber 2 to the absorber heat exchanger 27A.

The refrigerant separated by the low heat source regenerator 9 is
It flows into the second condenser 10 and is cooled and condensed. And
The refrigerant liquid flows down the second refrigerant liquid pipe 23, and the U seal portion 23
It collects in A and 22A. The refrigerant liquid accumulated in the U seal portions 23A and 22A overflows and flows into the evaporator 1. The refrigerant liquid that has flowed into the evaporator 1 and accumulated in the refrigerant liquid pool 1A flows through the refrigerant liquid circulation pipe 24 by the operation of the refrigerant liquid pump P3, and is sprayed from the refrigerant spraying device 1B to the cold / hot water heat exchanger 26B. Then, the cold water cooled by the latent heat when the refrigerant liquid is vaporized is supplied to the load from the cold / hot water heat exchanger 26B and the cold / hot water pipe 26C. Further, the refrigerant vaporized in the evaporator 1 flows to the absorber 2 and is absorbed by the concentrated absorbent spread from the concentrated absorbent dispersion device 2B.

The absorbing liquid which has become a dilute liquid by absorbing the refrigerant in the absorber 2 is sent to the low heat source regenerator 4 through the dilute absorbing liquid pipe 14 by the dilute absorbing liquid pump P1. Hereinafter, the control in the case where a sufficient amount of heat is not obtained from the heat source hot water against the cold water load during the cold water supply operation will be described. In this case as well, the temperature T1 of the cold water detected by the temperature sensor 34 is the temperature of each controller 3
6, 37, 38 respectively.

In this case, since a sufficient amount of heat for the cold water load cannot be given from the heat source hot water to the low heat source regenerator 9, the outlet temperature of the cold water cannot be lowered to the preset temperature of 6.5 ° C. Therefore, the controller 36, which has obtained the information from the main controller 30 that the temperature T1 of the cold water has not dropped to the predetermined set temperature, instructs the activation of the intermediate absorbent pump P2 and the ignition of the gas sonar 5, and The opening degree of the fuel control valve 5A is controlled based on the temperature T1 of the cold water obtained from the main controller 30. Therefore, the flow rate of the gas supplied to the gas burner 5 is controlled according to the temperature T1 of the cold water, the absorbing liquid is heated in the high temperature regenerator 4, and the refrigerant vapor is separated from the absorbing liquid.

Based on the temperature T2 of the cooling water detected by the temperature sensor 32 and the solution temperature T3 in the high temperature regenerator 4 detected by the temperature sensor 33, the controller 36 determines the intermediate absorption liquid pump P2.
The frequency of the electric power supplied to the intermediate absorber pump P2 is controlled by the frequency converter 40 as shown in FIG. 4, for example.
Control the rotation speed of. That is, the rated frequency is 6
In the case of 0 Hz, the lowest frequency is, for example, 28 Hz, which is half or less of the rated value, and the lower the cooling water temperature T2 is between the rated frequency and the lower frequency, the higher the temperature T3 of the solution in the high temperature regenerator 4, The conversion is performed so as to increase the frequency, and control is performed to increase the rotation speed of the intermediate absorption liquid pump P2.

The controller 37 gives an instruction to continue the rated operation of the dilute absorbent pump P1 based on the temperature information that the temperature T1 of the cold water obtained from the main controller 30 has not dropped to the set temperature of 7 ° C. To do. Therefore, the absorber 2, the low heat source regenerator 9, the high temperature regenerator 4, the high temperature heat exchanger 13, the low temperature regenerator 6,
The low-temperature heat exchanger 12, the first condenser 7, the second condenser 10, and the evaporator 1 form a single-double-effect refrigeration cycle, and can quickly cope with an increase in cold water load.

In the above-mentioned single-double-effect refrigeration cycle configuration, the controller 38 becomes the set value of the cold water outlet temperature T1 shown in FIG. 2 based on the return temperature T5 of the heat source hot water obtained from the temperature sensor 35. The flow rate control valve 29E is controlled as described above. That is, when the return temperature T5 of the heat source hot water falls below 82.5 ° C., the set value of the outlet temperature T1 of the cold water becomes high, and the controller 38 controls the flow control valve based on the detected outlet temperature T1 of the cold water and the set value. A signal for increasing the opening degree on the bypass pipe 29D side and decreasing the opening degree on the low heat source heat exchanger 29B side is output to 29E. Then, the opening degree of the flow control valve 29E on the bypass pipe 29D side increases, the heat source hot water flowing through the bypass pipe 29D increases, and the heat source hot water flowing toward the low heat source heat exchanger 29B side decreases. Therefore, the return temperature T5 of the heat source hot water rises. When the return temperature T5 of the heat source hot water exceeds 82.5 ° C,
The set value of the outlet temperature T1 of the cold water becomes low, and the controller 38 reduces the opening degree of the side passage pipe 29D to the flow control valve 29E based on the detected outlet temperature T1 of the cold water and the set value, and the low heat source heat A signal for increasing the opening on the side of the exchanger 29B is output.
Then, based on the signal from the controller 38, the flow control valve 2
The opening degree of 9E on the bypass pipe 29D side decreases, the heat source hot water flowing on the bypass pipe 29D decreases, and the heat source hot water flowing on the low heat source heat exchanger 29B side increases. Therefore, the return temperature T5 of the heat source hot water decreases.

As described above, the set value of the outlet temperature of the cold water for controlling the flow rate control valve 29E of the controller 38 changes based on the return temperature T5 of the heat source hot water, and the controller 38 controls the flow rate control valve 29E. Therefore, the temperature of the heat source hot water returning through the low heat source return pipe 29C is maintained at approximately 82.5 ° C. or higher. Thus, even when the heat quantity of the heat source hot water is insufficient with respect to the cold water load, the return temperature T5 of the heat source hot water does not drop significantly below a predetermined temperature, 82.5 ° C. in the embodiment. Even if the heat source hot water is returned to, for example, a generator and used for cooling, dew condensation does not occur, and the operation of the heat source hot water supply source can be stabilized.

Further, the return temperature T5 of the heat source hot water is about 8
Since it is stable at 2.5 ° C. or higher, the regeneration temperature of the low heat source regenerator 9 does not drop extremely, and is always maintained at the temperature required for refrigerant regeneration. Therefore, the heat source hot water is effective for refrigerant regeneration. It can also be used to improve COP. In the single-double effect refrigeration cycle described above, the intermediate absorption liquid from which a part of the refrigerant is separated in the low heat source regenerator 9 is the intermediate absorption liquid pump P2.
Is sent to the high temperature regenerator 4. In the high temperature regenerator 4,
The intermediate burner is heated by the gas burner 5 to evaporate and separate the refrigerant. The intermediate absorption liquid whose refrigerant has been separated in the high-temperature regenerator 4 and whose concentration has increased is sent to the low-temperature regenerator 6 via the high-temperature heat exchanger 13. The intermediate absorbing liquid is heated in the low temperature regenerator 6 by the refrigerant vapor sent through the refrigerant vapor pipe 20, and the refrigerant is evaporated and separated from the intermediate absorbing liquid. Then, the concentrated absorbent having a higher concentration is sent from the low temperature regenerator 6 through the low temperature heat exchanger 12 to the absorber 2, and is sprayed from the concentrated absorbent spraying device 2B.

The refrigerant vapor separated by the low heat source regenerator 9 is condensed by the second condenser 10, and the refrigerant vapor separated by the low temperature regenerator 6 is condensed by the first condenser 7. Then, the refrigerant liquid flows from the first condenser 7 and the second condenser 10 to the evaporator 1 via the first refrigerant pipe 22 and the second refrigerant pipe 23, and is sprayed from the refrigerant distributor 1B. In the evaporator 1, the cold water cooled by the cold / hot water heat exchanger 26B is supplied to the cold water load by latent heat when the refrigerant evaporates. Further, the refrigerant vapor that is vaporized in the evaporator 1 flows to the absorber 2 and is absorbed by the concentrated absorbent that is sprayed from the concentrated absorbent dispersion device 2B. The rare absorbent that has absorbed the refrigerant in the absorber 2 and has a reduced concentration is sent to the low heat source regenerator 9 by the rare absorbent pump P1.

When hot water is supplied to the load, the on-off valves 19V, 21V, 25V and 28V are opened and the high temperature refrigerant vapor generated in the high temperature regenerator 4 is transferred to the refrigerant vapor pipe 20A.
It is guided to the lower body 3 via the refrigerant vapor pipe 21. The water flowing through the cold / hot water heat exchanger 26B is heated by the refrigerant vapor sent to the lower case 3 and supplied to the load. In addition, the cold / hot water heat exchanger 2
The refrigerant liquid condensing by touching 6B and accumulated in the refrigerant liquid pool 1A is guided to the rare absorption liquid pool 2A through the refrigerant liquid drain pipe 25. Then, the rare absorption liquid is sent from the absorber 2 to the high temperature regenerator 4 through the low heat source regenerator 9 by the operation of the rare absorption liquid pump P1 and the intermediate absorption liquid pump P2.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the claims. For example, as shown by the alternate long and short dash line in FIG. 2, when the return temperature of the heat source hot water becomes lower than 80 ° C., which is a lower temperature than the above-mentioned embodiment, for example, the set value of the outlet temperature of the cold water is gradually increased. Similar to the example, set the return temperature of the heat source hot water to about 8
It can be maintained at 0 ° C or higher. Further, since the set value of the outlet temperature of the cold water is not changed to a temperature lower than that in the above-mentioned embodiment, the heat source hot water can be used more effectively even at a low temperature, and the COP of the absorption chiller can be further improved. .

Further, as indicated by the chain double-dashed line in FIG. 2, when the return temperature of the heat source hot water becomes lower than 80 ° C., the set value of the outlet temperature of the cold water of the controller 36 becomes high, for example 7.5 ° C. As a result, the return temperature of the heat source hot water can be maintained at approximately 80 ° C. or higher, as in the above embodiment. further,
Since the set value of the outlet temperature of the cold water is not changed to a temperature lower than that in the above-mentioned embodiment, the heat source hot water can be used more effectively to a lower temperature, and the COP of the absorption chiller can be further improved, and It is only necessary to change the set value of the outlet temperature of the cold water at 80 ° C., and the control can be simplified.

[0047]

The present invention is a single-double-effect absorption refrigerator constructed as in the above embodiment, and according to the invention of claim 1, the supply pipe and the return pipe of the low temperature heat source are communicated with each other. Is equipped with a three-way valve to control the heating amount of the high temperature regenerator based on the outlet temperature of the cold water extracted from the evaporator, the three-way valve is controlled based on the outlet temperature of the cold water, and the return temperature of the low temperature heat source is set to a predetermined value. When the temperature falls below the temperature, the set value of the chilled water outlet temperature for three-way valve control is increased, so the responsiveness to load fluctuations can be improved, regardless of the increase / decrease in low temperature heat source supplied to the low heat source regenerator and load fluctuations. The outlet temperature of cold water can be maintained at the set value.

When the return temperature of the low temperature heat source is lowered, the set value of the outlet temperature of the cold water is increased, the amount of the low temperature heat source flowing into the low temperature heat source regenerator is decreased, and the return temperature of the low temperature heat source is set to a predetermined temperature or higher. Therefore, even when the cooling water of the generator is used as a low-temperature heat source, it is possible to avoid troubles such as dew condensation when the generator is cooled by the low-temperature heat source whose temperature has dropped significantly. .

Further, it is possible to avoid the regeneration temperature of the low heat source regenerator from being extremely lowered, always maintain the temperature required for the regeneration of the refrigerant, and effectively perform the regeneration of the refrigerant to improve the COP. . Moreover, such an excellent effect can be obtained by operating a single three-way valve, and it is possible to provide a single-double-effect absorption refrigerator with excellent cost performance.

According to the second aspect of the invention, a three-way valve is provided so as to connect the supply pipe and the return pipe of the low temperature heat source, and the high temperature regenerator is based on the outlet temperature of the cold water taken out from the evaporator. Control the three-way valve based on the outlet temperature of the cold water, and when the return temperature of the low temperature heat source falls below a predetermined temperature, the set value of the cold water outlet temperature for controlling the three-way valve The responsiveness to load changes can be improved, and the outlet temperature of the cold water can be maintained at the set value regardless of the amount of low-temperature heat source supplied to the low heat source regenerator and the load changes.

When the return temperature of the low temperature heat source decreases, the amount of the low temperature heat source flowing into the low temperature heat source regenerator is gradually decreased according to the degree of the decrease, and the heat radiation amount in the low temperature heat source regenerator is decreased gradually. It is possible to maintain the return temperature of the low temperature heat source above a predetermined temperature regardless of load fluctuations, etc.
Even when the cooling water or the like of the generator is used as the low temperature heat source, it is possible to avoid a trouble such as dew condensation when the generator is cooled by the low temperature heat source whose temperature is significantly lowered.

Further, it is possible to prevent the regeneration temperature of the low heat source regenerator from dropping extremely, and to effectively utilize the heat of the low temperature heat source even when the amount of heat of the low temperature heat source changes, and to effectively regenerate the refrigerant. The COP can be improved. Further, according to the invention described in claim 3, a three-way valve is provided so as to connect the supply pipe and the return pipe of the low temperature heat source, and the heating amount of the high temperature regenerator is based on the outlet temperature of the cold water taken out from the evaporator. Control the three-way valve based on the outlet temperature of the cold water, and when the return temperature of the low temperature heat source falls below a predetermined temperature, the amount of the low temperature heat source flowing into the low temperature heat source regenerator is reduced with this decrease. As a result, the responsiveness to load changes can be improved, and the outlet temperature of cold water can be maintained at the set value regardless of the amount of low-temperature heat sources supplied to the low heat source regenerator and load changes.

When the return temperature of the low temperature heat source is lowered, the amount of low temperature heat source flowing into the low temperature heat source regenerator is reduced to reduce the amount of heat radiation in the low temperature heat source regenerator, and the return temperature of the low temperature heat source is set to a predetermined value. It is possible to maintain the temperature above the temperature, and even when the cooling water of the generator is used as a low temperature heat source, avoid troubles such as dew condensation when cooling the generator by the low temperature heat source whose temperature has dropped significantly. You can

Further, the regeneration temperature of the low heat source regenerator can be prevented from being extremely lowered, the temperature is always maintained at the temperature required for the regeneration of the refrigerant, and the refrigerant can be effectively regenerated to improve the COP. .

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a single-double-effect absorption refrigerator.

FIG. 2 is an explanatory diagram showing a relationship between a return temperature of heat source hot water and a cold water outlet temperature set value.

FIG. 3 is an explanatory diagram showing an example of control of a rare absorbent pump.

FIG. 4 is an explanatory diagram showing an example of control of an intermediate absorbent pump.

FIG. 5 is a schematic configuration diagram of a conventional single-double-effect absorption refrigerator.

[Explanation of symbols]

 1 Evaporator 2 Absorber 3 Lower body (Evaporator absorber body) 4 High temperature regenerator 6 Low temperature regenerator 7 First condenser 8 Low heat source regenerator Condenser body 9 Low heat source regenerator 10 Second condenser 11 Low temperature regeneration Condenser body 12 Low temperature heat exchanger 13 High temperature heat exchanger 26 Hot / cold water pipe 29D Side passage pipe 29E Flow control valve (three-way valve) 30 Main controller 38 Controller

Claims (3)

[Claims] 1. An evaporator absorber body containing an evaporator and an absorber, a low temperature regenerator condenser body containing a low temperature regenerator and a condenser, and a low heat source regenerator using hot wastewater as a low temperature heat source. A low heat source regenerator containing a condenser and a high temperature regenerator are connected by piping to form a circulation path for absorbing liquid and refrigerant, and a three-way valve is connected to connect the supply pipe and the return pipe of the low temperature heat source. It controls the heating amount of the high temperature regenerator based on the outlet temperature of the cold water extracted from the evaporator, controls the three-way valve based on the outlet temperature of the cold water, and the return temperature of the low temperature heat source is below a predetermined temperature. The single-double-effect absorption refrigerator is provided with a controller for increasing the set value of the cold water outlet temperature for controlling the three-way valve at the time of opening. 2. An evaporator absorber body containing an evaporator and an absorber, a low temperature regenerator condenser body containing a low temperature regenerator and a condenser, and a low heat source regenerator using hot wastewater as a low temperature heat source. A low heat source regenerator containing a condenser and a high temperature regenerator are connected by piping to form a circulation path for absorbing liquid and refrigerant, and a three-way valve is connected to connect the supply pipe and the return pipe of the low temperature heat source. The heating amount of the high temperature regenerator is controlled on the basis of the outlet temperature of the cold water taken out from the evaporator, the three-way valve is controlled on the basis of the outlet temperature of the cold water, and the return temperature of the low temperature heat source is lower than the predetermined temperature. A single-double-effect absorption refrigerating machine is provided with a controller for gradually increasing the set value of the cold water outlet temperature for controlling the three-way valve. 3. An evaporator absorber cylinder containing an evaporator and an absorber, a low temperature regenerator condenser cylinder containing a low temperature regenerator and a condenser, and a low heat source regenerator using hot wastewater as a low temperature heat source. A low heat source regenerator containing a condenser and a high temperature regenerator are connected by piping to form a circulation path for absorbing liquid and refrigerant, and a three-way valve is connected to connect the supply pipe and the return pipe of the low temperature heat source. The heating amount of the high temperature regenerator is controlled based on the outlet temperature of the cold water extracted from the evaporator, the three-way valve is controlled based on the outlet temperature of the cold water, and the return temperature of the low temperature heat source is lower than the predetermined temperature. At times, with this decrease, a single-double-effect absorption refrigerator is provided with a controller that reduces the amount of the low-temperature heat source flowing into the low-temperature heat source regenerator.