JPH06323686A - Heat pump type concentration difference heat accumulator and operation thereof - Google Patents

Abstract

PURPOSE:To contribute to the energy saving at the time of heat accumulation type air conditioning and at the time of heat accumulation by a hot water supplying device, improve the rising property and power saving at the time of heat radiation and unify the power load between daytime and nighttime by an increase of transfer rate of power use from the day time to the nighttime. CONSTITUTION:A heat pump type concentration difference heat accumulator is constituted of a combination of a compression type heat pump device including a compressor 1, a condenser 2, an expansion valve 3, an evaporator 4 and a preheater 16, and a concentration difference heat accumulator including a condensing container 5, a diluting container 6, a heat accumulating liquid storing tank 7 and a condensed liquid storing tank 8. A heat exchanger 16 is provided between a high temperature refrigerant gas system and a system to supply heat accumulating liquid from the heat accumulating liquid storing tank 7 to the condensing container 5 of the compression type heat pump device. Further, a cooler 11 is provided in a system to supply condensed heat accumulating liquid from the condensing container 5 to the condensed liquid storing tank 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for storing heat by night-time electric power and cooling during the daytime for the purpose of leveling an electric power load during the day and night, and more particularly to a heat storage type cooling system suitable for power saving.

[0002]

2. Description of the Related Art As a measure for stabilizing the operating rate of day and night of power generation equipment, it is desired to level the electric load during the day and night. Especially in the current situation where the load fluctuation of electric power during the summer cooling period is large and the capacity of the power supply side in the daytime is close to the limit, the cooling device is operated to store heat at night when the load on the power generation facility is small. There is a demand for a heat storage type cooling device that takes out cold heat during the daytime when a heavy load is placed on the power generation equipment.

As an example of such a heat storage type cooling device,
The present applicants previously combined a compression heat pump device and a concentration difference heat storage device, used the former condenser as the latter heater, and used the former evaporator as the latter condenser heat pump concentration difference heat storage device. (Japanese Patent Laid-Open No. 4-260)
759). FIG. 5 is a system diagram thereof.

The compression heat pump device includes a compressor 1 for compressing a refrigerant, an air heat exchange type condenser (which serves as an evaporator during heating operation) 2, an expansion valve 3 for adiabatically expanding the refrigerant, and a medium of an indoor air conditioner 10. A water-heat exchange type evaporator (which serves as a condenser during heating operation) 4 for exchanging heat between the refrigerant and the refrigerant, a four-way switching valve 1000, and a system (hereinafter, referred to as a system) 100, 110, 140, which connects them. , 190.

On the other hand, the concentration difference heat storage device includes a concentrating container 5 for concentrating the heat storage liquid, a diluting container 6 for diluting the heat storage liquid, a heat storage liquid storage tank 7, a condensate storage tank 8, a heat recovery unit 11, and a heat storage liquid storage tank 7. A pump 15 that sends the heat storage liquid to the heat recovery device 11, a pump 14 that sends the condensate in the condensate storage tank 8 to the dilution container 6, and a system 360, 370, ... .

The concentrating container 5 and the diluting container 6 respectively have heat storage liquid chambers 55 and 65 for temporarily storing a heat storage liquid and condensate liquid chambers 56 and 66 for storing a condensate liquid. They are connected so that steam can move between them. In addition, a device (not shown) such as an eliminator for removing mist (fine droplets) accompanying the moving vapor is provided at the communicating point. Further, in the concentrated heat storage liquid chamber 55 of the concentration container 5, a heater 51 and a liquid sprayer 53 for spraying the heat storage liquid to the heater are housed, and the condensed liquid chamber 5
A condenser 52 for condensing the vapor is housed in the inside of the container 6. Further, in the heat storage liquid chamber 65 of the dilution container 6, the absorber 6
1 and a liquid sprayer 63 for spraying a heat storage liquid to the absorber
In the condensate chamber 66, an evaporator 62 and a liquid sprayer 64 for spraying the condensate to the evaporator are housed.

At the tip of the upper nozzle and the lower nozzle of the heat storage liquid storage tank 7, a three-way valve (hereinafter referred to as a valve) 1120,
1100 is connected. In addition, these valves 112
The heat storage liquid return lines 430, 0, 1100,
The heat storage liquid discharge lines 360 and 370 are connected to each other. As other components, a cold water tower 9, an indoor air conditioner 10, and a hot water supply heat exchanger 12 are provided.

[0008]

In the concentration difference heat storage device, if the concentrated heat storage liquid concentrated at the time of concentrating the heat storage liquid is stored at a high temperature, it is necessary to cool this high temperature heat storage liquid at the time of cooling, that is, at the time of dilution operation. Therefore, until the cooling of the heat storage liquid is completed, chilled water having a temperature that can be used for cooling is not generated, so that the cooling activation time becomes long. Therefore, in the conventional example shown in FIG. 5, a method is adopted in which heat is exchanged between the concentrated high-temperature heat storage liquid and the low-temperature heat storage liquid in the heat recovery device 11, and the temperature is reduced as much as possible and stored.

However, there is a drawback that the temperature of the stored liquid gradually rises with the lapse of the heat storage operation time, and the cooling effect of the high temperature stored heat liquid after concentration is lowered. A method of generating cold water while cooling the high temperature heat storage liquid may be considered for the purpose of shortening the start-up time, but this method has a drawback in that the cooling heat amount decreases. Further, in the conventional concentration difference heat storage device, due to the difference between the heat of condensation of the heat pump refrigerant and the heat of vaporization during the concentration, a part of the heat of condensation is inevitably released to the outside of the system,
As a result, part of the electric energy required to drive the heat pump is wasted.

The present invention has been made in view of the above-mentioned drawbacks of the prior art. Firstly, it is intended to save electric power during heat storage of the heat storage type cooling device, and secondly, start at the time of heat output from cooling. The purpose is to shorten the time, and thirdly to increase the nighttime power utilization rate and contribute to the leveling of the power load during the day and night.

[0011]

According to the present invention, in a heat pump type concentration difference heat storage device in which a compression heat pump device and a concentration difference heat storage device are combined, a refrigerant of the compression heat pump device at the time of concentrating the heat storage liquid in the concentration difference heat storage device. The object is achieved by preheating the heat storage liquid with heat of condensation and by cooling and storing the concentrated heat storage liquid.

Further, according to the present invention, in the heat pump type concentration difference heat storage device in which the compression type heat pump device and the concentration difference heat storage device are combined, the heat storage liquid is stored from the heat storage liquid storage tank to the high temperature refrigerant gas system and the concentration container of the compression heat pump device. The above-described operation is enabled by providing a heat exchanger between the system for supplying the concentrated heat storage liquid and the system for supplying the concentrated heat storage liquid from the concentration container to the concentrate storage tank by means for cooling the concentrated heat storage liquid. .

[0013]

The heat storage operation in the concentration difference heat storage device is to heat and evaporate the heat storage liquid with the heat of condensation of the heat pump refrigerant, and to condense the generated vapor with the heat of evaporation of the refrigerant. Here, in principle, the amount of heat of condensation of the heat pump refrigerant is larger than the amount of heat of evaporation, so by utilizing a part of the heat of condensation for preheating the heat storage liquid, the above-mentioned difference in the amount of heat is eliminated and the heat efficiency is also improved.

Further, by cooling and storing the concentrated heat storage liquid at the time of heat storage, it is possible to improve the starting characteristics in the cooling heat output operation and also to save power. That is, at the time of heat output from cooling, the vapor pressure is lowered by cooling the concentrated heat storage liquid at the ambient temperature (usually the cooling water obtained in the cold water tower), and a low temperature is obtained by utilizing the phenomenon of absorbing vapor. is there. Therefore, the lower the temperature of the concentrated heat storage liquid is, the stronger its absorption capacity is, and the environment for obtaining a low temperature is prepared. According to the present invention, the heat storage liquid is concentrated and then stored in the heat storage liquid storage tank while being cooled, so that the cooling heat output can be promptly executed, and as a result, the cooling start time can be shortened.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a system of a heat pump type concentration difference heat storage device which is an embodiment of the present invention. In FIG. 1, portions having the same functions as those of the conventional example shown in FIG.

In this embodiment, a preheater 16 is provided in the system 380, and a cooler 11 connected to the cooling tower 9 is provided in the system 410 instead of the heat recovery device 11 in FIG. In the following description, R-22 is used as the refrigerant circulating in the heat pump device, and water is used as the medium passing through the cold water tower 9, the indoor air conditioner 10, the hot water supply heat exchanger 12, etc., but is not limited to this. Not a thing. The condenser 2 and the evaporator 4 are not limited to the illustrated air heat exchange type or water heat exchange type. Further, as the heat storage liquid, an aqueous salt solution such as an LiBr aqueous solution is generally used, and therefore the condensate becomes water.

A cooling operation, a heating operation, and a hot water supply operation carried out by the above device configuration and system will be described with reference to FIG.
In FIG. 2, only the systems related to the heat storage operation among the systems shown in FIG. 1 are numbered and shown. The gas of R-22, which has been compressed by the compressor 1 and whose temperature and pressure have risen, flows through the system 100, the four-way switching valve 1000, and the system 110, and by the valve 1010,
Flows to system 120. The non-condensable gas such as air in the concentration container 5 of the concentration difference heat storage device is removed by bleeding, and the above system is provided in the heat transfer tube of the heat exchanger of the heater 51 housed in the concentration container 5. R-22 gas from 120 flows in. At this time, the heat storage liquid is transferred from the storage tank to the system 3 by the pump 15.
After passing through 80 to the preheater 16 and being preheated by the heat of condensation of the R-22 gas, it is introduced into the liquid distributor 53 of the concentrating container via the system 400 and sprayed outside the heat exchanger heat transfer tube of the heater. To be done. By this operation, the heat storage liquid is heated and steam is generated. On the other hand, the R-22 gas becomes a wet gas, and passes through the system 130, the valve 1020, the systems 140, 141, and the preheater 1
6 is introduced.

In the preheater 16, the heat storage liquid is supplied to the concentration container by the system 380 as described above, and the heat storage liquid and R-
The 22 moist gas exchanges heat, the temperature of the heat storage liquid rises, the R-22 moist gas is liquefied, and further supercooled. Then system 14
2 and 150 flow to the expansion valve 3 and adiabatically expand to a low-temperature low-pressure wet gas, and the system 160, the valve 1030, the system 2
It is introduced into the heat exchange heat transfer tube of the condenser 52 via 10.

Since the above-mentioned water vapor is in contact with the outside of the heat transfer tube of the condenser 52, R-22 becomes saturated gas and the water vapor is cooled to be condensed water. R-22
The gas is introduced into the compressor 1 again through the system 220, the valve 1040, the system 190, the four-way switching valve 1000, and the system 200. On the other hand, the condensed water is introduced into the storage tank 8 through the system 510, the valve 1150, and the system 500.

The evaporatively concentrated heat storage liquid passes through a system 410,
In the cooler 11, the cooling water system 241 from the cold water tower 9 cools the valve 1130, the systems 430 and 460, and the valve 110.
It is introduced into the bottom of the heat storage liquid storage tank 7 via 0. As described above, the heat storage liquid is concentrated and then cooled and stored. As will be described later, this concentrated heat storage liquid has an enhanced property of absorbing water vapor, and as a result, it stores heat.

Next, the heat output for cooling will be described with reference to FIG. In FIG. 3, only the systems related to the cooling operation among the systems shown in FIG. 1 are numbered and shown. The R-22 gas, which has been compressed by the compressor 1 and whose temperature and pressure have increased, reaches the valve 1010 in the same flow as in the heat storage operation, and is further introduced into the condenser 2 via the valve 1020 and the system 140. The heat transfer tube 21 of the condenser 2 is cooled by air or the like, and R-2
The two gases are liquefied and then pass through the system 150 and undergo adiabatic expansion when passing through the expansion valve 3 to become low-temperature low-pressure wet gas. Then, it is introduced into the evaporator 4 via the valve 1030 and the system 170.

In the heat transfer tube of the heat exchanger 41 of the evaporator 4,
As will be described later, cold water cooled in the evaporator 62 of the concentration difference heat storage device (for example, to about 10 ° C.) is introduced from the system 280, and this cold water is further cooled (for example, to about 7 ° C.) in the evaporator 4. System 310, 330, valve 1090, system 3
After 50, it is introduced into the heat transfer tube 101 of the indoor air conditioner 10.

By this action, R-22 evaporates to a state near saturated gas, and the system 180, valve 1040, system 19
0, the four-way switching valve 1000, and the system 200, and is again introduced into the compressor 1. On the other hand, the cooling water from the cooling tower 9 is circulated in the pipe by the pump 12 in the absorber 61 of the dilution container 6 (not shown, the non-condensable gas is removed by the extraction system) of the concentration difference heat storage device. Since the concentrated heat storage liquid is sprayed outside the pipe from the bottom of the heat storage liquid storage tank 7 by the pump 15, the liquid sprayer 63, etc., the inside of the dilution container 6 is kept at a low pressure.

Further, the evaporator 62 is provided with the heat output exchanger 101 of the indoor air conditioner 10 (for example, about 12 ° C.).
Up to the cold water that has been heated up to the system 340, valve 1080, system 3
20, the valve 1070, the system 300, the pump 13, and the system 290 are introduced, and the outside of the pipe is from the condensed water storage tank 8 to the pump 1
4. Condensed water is sprayed by the liquid sprayer 64 and the like. With such an action, the condensed water evaporates at a low temperature, the latent heat of vaporization lowers the temperature of the cold water introduced from the system 290, and the cooled cold water flows from the system 280 to the evaporator 4 described above.

As described above, in the cooling heat output operation, the cold water that has taken heat from the room to raise its temperature (for example, about 12 ° C.) is first cooled in the dilution container 6 of the concentration difference heat storage device (for example, to about 10 ° C.). Then, the temperature is further lowered in the evaporator 4 of the compression cycle to obtain cold water having a predetermined temperature (for example, about 7 ° C.). Here, the operation of the preheater 16 will be described with reference to FIGS. 2 and 4.

FIG. 4 shows the state of the refrigerant in a typical heat pump cycle. The horizontal axis shows the enthalpy,
The pressure is plotted on the vertical axis, and the saturated liquid line with temperature as a parameter,
The saturated vapor line and the wetness line are shown. As shown in FIG. 2, the R-22 compressed by the compressor 1 becomes high-temperature and high-pressure superheated steam (indicated by “a” in FIG. 4, hereinafter referred to as “a”), and is stored in the heat exchanger 51 of the concentration container 5. It is introduced and condenses into moist steam. It is the position of b of FIG. 4, and this position is (dc ')
= (Ab). This moist steam is preheater 1
6 is introduced into the saturated liquid b ′ or the supercooled liquid b ″ and then flows to the expansion valve 3. The expansion valve 3 adiabatically expands and lowers the temperature to obtain low-temperature low-pressure wet steam c ″ or c ′. R-
22 is introduced into the heat exchanger 52 of the concentrator 5 and evaporated to become saturated vapor d, which is again introduced into the compressor 1 via the system 220, the valve 1040, the system 190 and the like. In this cycle, as described above, (d-
Since the heat quantity of c ′) is almost equal to the heat quantity of (ab), it is necessary to cool b to b ′ by some means in order to establish this cycle. This cooling is performed by a cooling source (air in FIG. 5) outside the system as seen in the conventional example of FIG. Therefore, the heat from b to b'is discharged to the outside of the system, and as a result, the electric power required for the compression of R-22 is to be discarded to the outside of the system.

On the other hand, in the present invention, by providing the preheater 16 and the systems 141 and 142, it becomes possible to utilize the heat from b to b ′ described above for raising the temperature of the heat storage liquid, and as a result, the electric power. Waste of money can be eliminated. Furthermore, when the heat storage liquid is at a lower temperature, it is possible to supercool R-22 to the position of b ″. In this case, the condensation heat quantity is (dc) as shown in FIG. As a result, the heat of condensation increases more than the conventional (dc '), and as a result, the coefficient of performance of the heat pump (generally referred to as COP, COP is the heat of condensation required for compression (a-c-)). (represented by the value divided by b)) is improved, resulting in power saving.

Further, in the present invention, the cold water tower 9 as shown in FIG. 2 is used as an example of the method for cooling the concentrated heat storage liquid during heat storage. Electric power is, of course, required to operate the cold water tower, but heat storage (concentration) is generally performed at night, and cooling can be performed with inexpensive nighttime power. Further, since the outside air temperature is lower at night than in the daytime, it is possible to reduce power consumption such as reduction of pump power and cooling water tower fan power by reducing cooling water circulation flow rate.

In this embodiment, the case where the low temperature generated by the concentration difference heat storage device and the low temperature generated by the compression type heat pump device are connected to the cascade has been described, but either one of the low temperatures is used independently. Of course, you can Furthermore, by connecting the system 280 and the system 330,
When the low temperature generated by the compression heat pump device and the low temperature generated by the concentration difference heat storage device are set to the same level, both low temperatures can be connected in parallel and used.

[0030]

As described above, according to the present invention, in the heat pump type concentration difference heat storage device in which the compression type heat pump device and the concentration difference heat storage device are combined, the concentrating container is formed by the excess heat of the refrigerant condensation heat used as the heat source of the heat storage liquid. A system that preheats the heat storage liquid that is introduced into the heat storage liquid is provided, and a part of the refrigerant condensation heat is used for the residual heat of the heat storage liquid when the heat is stored.
Can be improved to save power. In addition, by providing a system for cooling the concentrated heat storage liquid that has been evaporated and concentrated, and cooling and storing the concentrated heat storage liquid during heat storage, it is possible to improve the start-up characteristics during cooling heat output and also to conserve power. it can. In addition, it has the effect of increasing the rate of shifting the power load to the nighttime and contributing to the leveling of the power load during the day and night.

[Brief description of drawings]

FIG. 1 is a diagram showing components and a piping system of an embodiment of the present invention.

FIG. 2 is a diagram in which only devices and systems related to heat storage operation in FIG. 1 are numbered.

FIG. 3 is a diagram in which only the devices and systems related to the cooling heat output operation in FIG. 1 are numbered.

FIG. 4 is a refrigerant state diagram of a typical heat pump cycle.

FIG. 5 is a diagram showing components and a piping system of a conventional example.

[Explanation of symbols]

1 ・ ・ Compressor, 2 ・ ・ Condenser (evaporator in heating / hot water supply operation), 3 ・ ・ Expansion valve, 4 ・ ・ Evaporator (condenser in heating / hot water supply operation), 5 ・ ・ Concentration Container, 6 ... Diluting container, 7 ... Heat storage liquid storage tank, 8 ... Condensed water storage tank, 9 ... Cold water tower, 10 ... Indoor heat exchanger, 11 ... Cooler, 12 ...
・ Hot water heat exchanger, 16 ・ ・ Preheater, 100-510 ・
・ Piping system, 1000 ・ ・ 4-way switching valve, 1010
1170 ... Switching valve

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Katsuya Ehara 4-6 Kanda Surugadai, Chiyoda-ku, Tokyo Inside Hitachi, Ltd. (72) Inventor Shuzo Sano 3-11-20 Wakaoji, Amagasaki City, Hyogo Prefecture Kansai Electric Power Company (72) Inventor Hisataka Enomoto 3-11-20 Wakaoji, Amagasaki City, Hyogo Prefecture Kansai Electric Power Co., Inc.

Claims (4)

[Claims] 1. A compression type heat pump device comprising a compressor, an expansion valve, a condenser part and an evaporation part which are connected to form a closed circuit in which a refrigerant is sealed, and a heat storage liquid is heated by a high temperature part of the compression heat pump device. Concentration container for evaporating and concentrating and cooling and condensing the vaporized vapor at a low temperature part, dilution container for generating a low temperature by a process including a process of absorbing condensed liquid vapor in a concentrated heat storage liquid, respectively connected to the concentration container and the dilution container In a heat pump type concentration difference heat storage device in which a concentration difference heat storage device including a stored heat storage liquid storage tank and a condensed liquid storage tank is combined, a heat storage liquid is supplied from the heat storage liquid storage tank to the high temperature refrigerant gas system of the compression heat pump device and the concentration container. A heat pump type concentration difference heat storage device, characterized in that a heat exchanger is provided between the heat pump type and the system. 2. The heat pump type concentration difference heat storage device according to claim 1, wherein a means for cooling the concentrated heat storage liquid is provided in a system for supplying the concentrated heat storage liquid from the concentration container to a concentrated liquid storage tank. 3. A compression heat pump device that generates a high temperature by adiabatic compression of the refrigerant and a low temperature by adiabatic expansion of the refrigerant, and the compression heat pump that heats and evaporates the heat storage liquid at the high temperature generated by the compression heat pump device. By a process including a process of storing the heat storage liquid as a concentrated heat storage liquid and a condensed liquid by cooling and condensing the evaporative vapor at a low temperature generated in an apparatus, and allowing the concentrated heat storage liquid to absorb the vapor of the condensed liquid. In combination with a concentration difference heat storage device that generates a low temperature, the low temperature generated by the compression type heat pump device and the low temperature generated by the concentration difference heat storage device are used alone or connected in parallel or in cascade to be used as a cold heat source. In a method of operating a heat pump type concentration difference heat storage device, the pressure is applied when the heat storage liquid is concentrated in the concentration difference heat storage device. Operation method of a heat pump type density difference thermal storage apparatus characterized by preheating the thermal storage fluid by refrigerant condensing heat equation heat pump apparatus. 4. The method of operating a heat pump type concentration difference heat storage device according to claim 3, wherein the concentrated heat storage liquid is cooled and stored.