JP3244774B2 - Automatic cooling / heating switching method and apparatus in absorption chiller / heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for efficiently and automatically switching an absorption chiller / heater from a hot water discharge operation to a cold water discharge operation or a simultaneous cold and hot water discharge operation without excessively increasing the temperature of the cooling water. About.

[0002]

2. Description of the Related Art Conventionally, an absorption chiller / heater using, for example, lithium bromide as an absorbent and water as a refrigerant is generally known. A conventional absorption chiller / heater has, for example, a configuration as shown in FIG. Reference numeral 1 denotes an upper low-temperature body, which is composed of a low-temperature regenerator 2 and a condenser 3, and further, a refrigerant reservoir 4 is provided in a lower part in the condenser 3. Reference numeral 5 denotes a lower low temperature body, which comprises an evaporator 6 and an absorber 7. Reference numeral 8 denotes a high-temperature regenerator, which includes a combustion chamber 9, a heat recovery unit 10, and a gas-liquid separator 1.
1, an exhaust stack 12 and a combustion device 13. In addition, the low-temperature heat exchanger 14, the high-temperature heat exchanger 15, and the like are constituent devices. The dilute solution in the lower sump 16 in the absorber 7 is
The low-temperature pump 17 sends the liquid to the low-temperature regenerator 2 via the absorption liquid lines 18 and 19, the low-temperature heat exchanger 14, and the line 20.
The rare liquid is heated by the high-temperature refrigerant vapor flowing from the refrigerant vapor line 21 and concentrated to an intermediate concentration. This intermediate concentration liquid is bisected. One of the two halves is
Pipes 23 and 24, high-temperature heat exchanger 1 by high-temperature pump 22
5. It is sent to the high temperature regenerator 8 via the pipe 25. This intermediate-concentration liquid is heated by the combustion device 13 and the heat recovery device 10
And enters the gas-liquid separator 11 where it is separated into refrigerant vapor and concentrated liquid. This concentrated liquid has a pressure of about 650 in the high-temperature regenerator 8.
Due to the pressure difference between mmHg and the pressure inside the lower low-temperature cylinder 5 of about 6 mmHg, the intermediate liquid (from the pipe 28 previously divided via the concentrated liquid pipe 26, the high-temperature heat exchanger 15 and the pipe 27) And mixed into the low-temperature heat exchanger 14 as a mixed concentrated liquid, and is sprayed on the heat transfer tube of the absorber 7 through the pipe 29 by the spraying device 30, and A return cycle is made.

On the other hand, the refrigerant vapor separated by the gas-liquid separator 11 enters the low-temperature regenerator 2 through the refrigerant vapor line 21, heats the liquid, condenses and liquefies the liquid, and the refrigerant flows through the refrigerant liquid line 46 through the condenser liquid line 46. 3
to go into. In the low-temperature regenerator 2, the refrigerant vapor generated when the rare liquid is concentrated to the intermediate concentration liquid enters the condenser 3 from the upper space and is condensed to be a refrigerant liquid. The condensed refrigerant water enters the evaporator 6 via the pipe 31 and is accumulated in the lower sump 32. This refrigerant water is passed through pipelines 34 and 35 by a refrigerant pump 33, and the evaporator 6 is
Sprayed on the heat transfer tubes. The cold water for cooling is
The refrigerant enters the evaporator 6 through the pipe 37, is cooled by the latent heat of evaporation of the dropped refrigerant, and flows out of the cold / hot water discharge pipe 38.
The cooling water flows out through the pipes 39, 40 and 41, and takes out the heat of absorption in the absorber 7 on the way and the heat of condensation in the condenser 3 and takes it out of the system. Further, by opening the manual cooling / heating switching valve 60 and further stopping the cooling water supplied to the cooling water pipe 39,
Hot water can be obtained from the cold / hot water outlet pipe 38. In the conventional absorption chiller / heater shown in FIG. 6, a cooling tower (not shown) is connected to the cooling water discharge pipe 41, and the cooling water heated by the cooling tower is cooled and then used again. ing.

[0004]

In the conventional absorption chiller / heater shown in FIG. 6, when switching from the hot water discharge operation to the cold water discharge operation, the temperature of the cooling water staying in the heat transfer pipe of the chiller / heater becomes high. If the cooling water pump is operated and the cooling water is circulated as it is, there is a problem that the filler filled in the cooling tower is dissolved and deteriorated. Further, in the conventional absorption chiller / heater shown in FIG. 6, when switching from the hot water removal operation to the chilled water removal operation, when the cooling water is passed while the temperature of the absorbing liquid in the chiller / hot water heater, particularly in the absorber is high. However, there is a problem that the pressure inside the water-cooled / hot-water machine body suddenly drops, the absorbing liquid inside the body suddenly boil, and the absorbing liquid jumps into a refrigerant system, for example, an evaporator or a condenser, so that the operation cannot be resumed as it is. The present invention has been made in view of the above points, and does not increase the cooling water temperature so much, and does not cause the internal absorbing liquid to boil, and switches from the hot water discharging operation to the cold water discharging operation or the cold and hot water simultaneous discharging operation. It is an object of the present invention to provide a method and an apparatus capable of performing the above-described operations.

[0005]

In order to achieve the above object, a method of automatically switching between cooling and heating in an absorption chiller / heater according to the present invention will be described with reference to the drawings. Alternatively, at the time of switching to the cold water / hot water simultaneous removal operation, the temperature of the absorption liquid extracted from the absorber 7 is measured, and when the temperature falls below a predetermined temperature (for example, about 40 ° C.), the cooling water is passed to start the cold water removal operation. It is characterized by: In another method of the present invention, when switching from the hot water discharge operation to the cold water discharge operation or the cold / hot water simultaneous discharge operation, the cooling water temperature of the absorber 7 and the condenser 3
Is characterized in that at least one of the cooling water temperatures is measured, and when the temperature falls below a predetermined temperature (for example, about 50 ° C.), the cooling water is passed. In this method, until the cooling water drops to a predetermined temperature (for example, about 50 ° C.)
It is desirable to open the cooling water blow valve 98 connected to the cooling water supply pipe 39 so as to lower the temperature of the cooling water in the absorber 7 and the condenser 3.

[0006] The apparatus of the present invention will be described with reference to the drawings in an absorption chiller / heater provided with an evaporator 6, an absorber 7, a condenser 3, a low-temperature regenerator 2 and a high-temperature regenerator 8.
A cooling water shutoff valve 104 or a cooling water pump is provided in the cooling water supply line 39, and the temperature detector 1 is connected to the absorption liquid line 19.
06, a temperature detector 108 in the cooling water supply pipe 39 near the absorber 7 and a temperature detector 110 in the cooling water discharge pipe 41 near the condenser 3 to provide a cooling water cutoff valve 104 or a cooling water pump. , And at least one of the temperature detectors 106, 108, 110 is connected via a controller 112. The temperature of the absorbing liquid is detected by the temperature detector 106, the temperature of the cooling water in the absorber 7 is detected by the temperature detector 108, and the temperature of the cooling water in the condenser 3 is detected by the temperature detector 110. When the temperature becomes equal to or lower than the predetermined temperature, control is performed such that the cooling water cutoff valve 104 is opened via the controller 112 or the cooling water pump is operated.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. However, the shapes of the components described in this embodiment, the relative arrangement thereof, and the like are not intended to limit the scope of the present invention to them only, unless otherwise specified, and are merely illustrative examples. It's just FIG. 1 shows an embodiment of a cooling / heating automatic switching device according to the present invention. The apparatus shown in FIG. 1 is different from the conventional absorption chiller / heater shown in FIG. 6 in that a cooling water cutoff valve 104 or a cooling water pump is provided in a cooling water supply pipe 39 and a temperature detector 106 is provided in an absorption liquid pipe 19. , Cooling water supply pipe 39 near absorber 7
And a temperature detector 110 in the cooling water discharge pipe 41 near the condenser 3, and a cooling water shutoff valve 104.
Alternatively, a cooling water pump and temperature detectors 106, 108, 110
Are connected via the adjuster 112. The temperature detector 108 may be connected to a cooling water pipe in the absorber 7,
Further, the temperature detector 110 may be connected to a cooling water pipe in the condenser 3. The same equipment and piping as in FIG.
With the same number. Other configurations and operations are the same as those in FIG.

FIG. 2 shows another example of the apparatus of the present invention. The apparatus shown in FIG. 2 is different from the apparatus shown in FIG. 1 in that a blow pipe 100 provided with a coolant blow valve 98 and a water quality detector 102 is connected to a coolant supply pipe. Then, the blow valve 98 is operated until the cooling water drops to a predetermined temperature.
Is opened to lower the temperature of the cooling water in the absorber 7 and the condenser 3.

In the absorption chiller / heater shown in FIG. 1 and FIG. 2, hot water can be taken out only from the cold / hot water take-out line 38 from the evaporator 6, and hot water of a different temperature is required. It cannot cope with a case where hot water for heating and hot water for heating are required. In view of this point, the present inventor attaches one or more water heaters to the low-temperature regenerator, introduces the refrigerant vapor that has passed through the low-temperature regenerator tube into the water heater, and turns off the evaporator in the heating operation mode. Other than hot water to take out,
The present invention has invented a hot water multi-circuit discharge absorption chiller / heater which can take out hot water at the same time or / and arbitrarily by the above-mentioned water heater, or can take out hot water from only one or a plurality of water heaters. Of course, at the time of taking out cold water, hot water can be taken out simultaneously or / and arbitrarily from one or more water heaters.

FIG. 3 shows an example of an absorption chiller / heater for taking out multiple circuits of hot water. The absorption chiller / heater shown in FIG. 3 is different from the absorption chiller / heater shown in FIG. 1 in that a water heater 64 is connected to the low temperature regenerator 2 and a heat exchanger 90 is provided in the low temperature drum 5. The same devices and pipes as those in FIG. 1 are given the same numbers as those in FIG. The absorption chiller / heater includes an evaporator 6, an absorber 7, a condenser 3, a low-temperature regenerator 2 and a high-temperature regenerator 8,
A state where cold water is taken out from the evaporator 6 via the pipe 38 in the cooling mode (at this time, the cooling / heating switching valve 60 is closed) and a state where hot water is taken out from the evaporator 6 via the pipe 38 in the heating mode (at this time, the cooling / heating switching valve) 60 is open). In the above configuration, the low-temperature regenerator 2
Of the water heater 6 through the refrigerant vapor line 62 to the refrigerant liquid line 46
4 are connected. A valve 96 of an orifice plate or a float type is provided in the refrigerant liquid pipeline 46 so as to seal the pressure on the high-temperature regenerator side with high pressure and the condenser side with low pressure. As shown in FIG. 4, two or three or more water heaters 64 can be installed. 3 and 4, the high-temperature regenerator 8 and the low-temperature regenerator 2 are connected via a refrigerant vapor line 21, and guide the high-temperature refrigerant vapor generated in the high-temperature regenerator 8 to the low-temperature regenerator 2. , To the water heater 64.

Also, the refrigerant drain line 6 of the water heater 64 is arranged so that the refrigerant drain condensed in the water heater 64 is returned to the refrigerant system.
6 is connected to the condenser 3 or the low-temperature regenerator. Therefore, the refrigerant drain condensed in the water heater 64 can be returned to the refrigerant system without returning to the absorption liquid side, and can be effectively used for cooling to save energy. Further, a heat exchanger 90 is provided in the low-temperature cylinder 5 composed of the evaporator 6 and the absorber 7, and a hot water inlet of the heat exchanger 90 and a hot water supply line 7 of the water heater 64 are provided.
8 is connected via a hot water supply branch pipe 92, and the hot water outlet of the heat exchanger 90 and the hot water extraction pipe 70 of the water heater 64 are connected via a hot water extraction branch pipe 94. The heat exchanger 90 may be provided outside the cylinder 5 and connected to the cylinder 5.
As described above, before hot water is put into one or a plurality of water heaters 64, or a part of the hot water is placed in the body 5 composed of the evaporator 6 and the absorber 7 or outside the body connected to the body 5. The pressure in the body 5 is lowered with low-temperature hot water so as to guide the absorbent to the heat exchanger 90 so that the absorbent can flow normally when the hot water is operated alone by the hot water device 64. If the heat exchanger 90 is not provided, the pressure in various places may be reversed from that in normal operation depending on the operating conditions (for example, the pressure in the lower low temperature cylinder 5 becomes higher than the pressure in the upper low temperature cylinder 1), and the liquid Flow may not be performed normally. When the heat exchanger 90 is provided, the refrigerant vapor in the body 5 is condensed by the heat exchanger 90 to lower the pressure, so that such an abnormality does not occur, and switching between the cold water operation, the hot water operation, and the simultaneous operation of the cold water and the hot water is performed. However, there is an advantage that operation can be performed without providing special valves and opening and closing these valves.

As shown in FIG. 5, a temperature detector 68 is provided in a cold / hot water outlet line 38 from the evaporator 6, and a temperature detector 72 is provided in a hot water outlet line 70 from the hot water device 64. These temperature detectors 68 and 72 and the fuel control valve 74 for the combustion device 13 of the high temperature regenerator 8 are connected via a deviation value judging device 76. When simultaneously taking out cold water and hot water or hot water from a plurality of water heaters 64, a temperature control deviation value of the cold water temperature and / or the hot water temperature is captured, and the larger the deviation value, the larger the capacity control (mainly the combustion control). ). A hot water supply pipe 78 to the water heater 64 is provided with a hot water three-way control valve 80, and the hot water supply pipe 78 and the hot water extraction pipe 70 are connected via a bypass pipe 82 passing through the hot water three-way control valve 80. ing. Further, the temperature detector 7 provided in the hot water three-way control valve 80 and the hot water discharge pipe 70 is provided.
2 is connected so that the hot water three-way control valve 80 can be controlled by the temperature of the extracted hot water. For this reason, the evaporator 6
When the capacity control is performed by the cold water temperature or the hot water temperature taken out from the water heater, the temperature of the hot water taken out from one or more water heaters 64 can be controlled by another control mechanism such as the hot water three-way control valve 80.

The absorption liquid line 19 from the absorber 7 and the refrigerant liquid line 31 from the condenser 3 are connected via an absorption liquid line 86 provided with a flow control valve 84, and the flow rate is controlled. The temperature detector 68 provided in the valve 84 and the cold water discharge line 38
Are connected so that the flow control valve 84 can be controlled by the temperature of the cold water. In this way, when the capacity control is performed by the temperature of the hot water taken out from one or more water heaters 64, the temperature of the cold water is controlled by another control mechanism such as putting the absorbing liquid into the refrigerant system. be able to. Further, the manual cooling / heating switching valve 60 provided in the refrigerant liquid line connecting the refrigerant liquid line 46 at the bottom of the low temperature regenerator 2 and the evaporator 6 is changed to a cooling / heating automatic switching valve 88, and this cooling / heating automatic switching is performed. The valve 88 and the temperature detector 68 provided in the cold / hot water discharge pipe 38 are connected so that the cooling / heating automatic switching valve 88 can be controlled by the cold water temperature. In this manner, when the capacity control is performed by the temperature of the hot water taken out from one or more water heaters 64, the temperature of the hot water taken out of the evaporator 6 is controlled by other means such as opening and closing the cooling / heating automatic switching valve 88. It can be controlled by a control mechanism.

In the above-described hot water multi-circuit removal absorption chiller / heater, the hot water alone operation for extracting hot water from the evaporator 6 or the hot water combined operation for extracting hot water from the water heater 64 is also used. When the operation is switched to the operation, by completely closing the cooling / heating automatic switching valve 88, it is possible to easily switch between the individual withdrawal of the hot water alone and the combination with the hot water.

In the hot water multi-circuit take-out absorption chiller / heater shown in FIGS. 3 to 5, the cooling water supply pipe 39 has a cooling water cutoff valve 104 or a cooling water pump as in the case of FIGS. And a temperature detector 106 in the cooling water supply pipe 39 near the absorber 7 and a temperature detector 110 in the cooling water discharge pipe 41 near the condenser 3. Is provided, and the cooling water shut-off valve 104 or the cooling water pump is connected to the temperature detectors 106, 108, 110 via the controller 112.

[0016]

As described above, the present invention has the following effects. (1) When switching from hot water discharge operation to cold water discharge operation or cold / hot water simultaneous discharge operation, the cooling water outlet temperature can be automatically lowered and switched to an appropriate temperature to prevent deterioration of the filler in the cooling tower. can do. Further, in the conventional absorption chiller / heater, when switching from the hot water removal operation to the chilled water removal operation, when the cooling water flows through the chiller / heater, particularly when the temperature of the absorbent in the absorber is high, the chiller / heater is operated. The pressure inside the body drops sharply, the absorbing liquid inside the body suddenly boil, and the absorbing liquid jumps into the refrigerant system, for example, the evaporator or the condenser, and it becomes impossible to start the cooling operation as it is. After the temperature is measured and the temperature becomes equal to or lower than the predetermined temperature, if the cooling water is passed, the operation can be smoothly shifted to the cooling operation.

[Brief description of the drawings]

FIG. 1 is a flow sheet showing an embodiment of an automatic cooling / heating switching device in an absorption chiller / heater of the present invention.

FIG. 2 is a flow sheet showing another embodiment of the apparatus of the present invention.

FIG. 3 is a flow sheet showing another embodiment of the apparatus of the present invention.

FIG. 4 is a flow sheet showing another embodiment of the apparatus of the present invention.

FIG. 5 is a flow sheet showing still another embodiment of the apparatus of the present invention.

FIG. 6 is a flow sheet showing an example of a conventional absorption chiller / heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper low temperature body 2 Low temperature regenerator 3 Condenser 5 Lower low temperature body 6 Evaporator 7 Absorber 8 High temperature regenerator 13 Combustion device 19 Absorbent liquid line 21 Refrigerant vapor line 31 Refrigerant liquid line 38 Cold and hot water extraction line 39 Cooling water supply line 41 Cooling water discharge line 46 Refrigerant liquid line 60 Manual cooling / heating switching valve 62 Refrigerant vapor line 64 Water heater 66 Refrigerant drain line 68 Temperature detector 70 Hot water discharge line 72 Temperature detector 74 Fuel control Valve 76 Deviation value judging device 80 Hot water three-way control valve 82 Bypass line 84 Flow rate control valve 86 Absorbent line 88 Cooling / heating automatic switching valve 90 Heat exchanger 92 Hot water supply branch line 94 Hot water extraction branch line 96 Orifice plate 98 Cooling Water blow valve 100 Blow pipe 102 Water quality detector 104 Flow control valve 106 Temperature detector 108 Temperature detector 110 Temperature detector 112 The amount adjuster

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-62-129662 (JP, A) JP-A-56-85668 (JP, A) JP-A-59-225265 (JP, A) JP-A-61-125265 186766 (JP, A) JP-A-5-248723 (JP, A) JP-A-52-9149 (JP, A) JP-A-3-5677 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25B 15/00 306

Claims (4)

(57) [Claims] When switching from a hot water discharge operation to a cold water discharge operation or a simultaneous cold and hot water discharge operation, the temperature of an absorbing liquid extracted from an absorber (7) is measured, and when the temperature falls below a predetermined temperature, cooling water is passed through. And an automatic cooling / heating switching method in the absorption chiller / heater, wherein a cooling water removal operation is started. 2. When switching from the hot water discharge operation to the cold water discharge operation or the cold / hot water simultaneous discharge operation, at least one of the cooling water temperature of the absorber (7) and the cooling water temperature of the condenser (3) is measured. Cooling / heating automatic switching method in an absorption chiller / heater, wherein the cooling water is passed when the temperature becomes equal to or lower than a predetermined temperature. 3. A cooling water blow valve (9) connected to a cooling water supply pipe (39) until the cooling water drops to a predetermined temperature.
3. The method according to claim 2, wherein the temperature of the cooling water in the absorber (7) and the condenser (3) is lowered. 4. An absorption chiller / heater comprising an evaporator (6), an absorber (7), a condenser (3), a low-temperature regenerator (2) and a high-temperature regenerator (8). A cooling water shut-off valve (104) or a cooling water pump is provided in (39), a temperature detector (106) is provided in the absorbing liquid pipe (19), and a cooling water supply pipe (39) near the absorber (7). The temperature detector (108) is connected to the cooling water discharge pipe (41) near the condenser (3).
10), a cooling water shutoff valve (104) or a cooling water pump, and temperature detectors (106), (108), (110).
A cooling / heating automatic switching device in the absorption chiller / heater, wherein at least one of the devices is connected via a controller (112).