JPS61243261A - Air-conditioning system utilizing latent heat - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention aims to reduce heating and cooling costs by using cold storage and heat storage sources obtained using nighttime electricity as thermal energy for heating and cooling operations during the day. Regarding heating and cooling systems.

``Conventional technology'' The use of nighttime electricity for cooling during the summer is particularly encouraged as it helps level out the electricity load. The remaining heat is stored in a cold storage tank such as an ice bank using the latent heat of ice.
During daytime cooling operation, the cooling load is not directly transferred to the air conditioner, and cooling is mainly performed using ice latent heat.On the other hand, during winter heating, the air conditioner operates as a heat pump, producing hot water using nighttime electricity, which is then pumped underground. 2. Description of the Related Art A so-called late-night power-using type air-conditioning/heating system is known, which stores heat in a large heat storage tank installed in a large heat storage tank and performs daytime heating operation using the thermal energy in the heat storage tank.

``Problem to be solved by the invention'' However, unlike the cold storage tank used for summer cooling, the heat storage tank used for winter heating uses sensible heat, so it requires a considerably larger volume than the cold storage tank, and has a higher strength. In addition, since it is installed underground and isolated from mechanical equipment for heat retention, not only does the construction cost for installing an underground tank increase, but also the piping work cost to connect the compressor and other mechanical equipment. costs extra.

In addition, in the case of heating and cooling buildings, the mechanical equipment is generally placed on the rooftop, but if such a configuration is adopted, pump power for pumping water is required, and operating costs are also increased.

Also, if the mechanical equipment is placed below, the refrigerant piping becomes complicated and efficiency is not good.

On the other hand, if the cold storage tank could be used also as a heat storage tank in the winter, the above disadvantages would be solved, but the melting point of the cold storage tank is 0°C, and the temperature range (20 to 30°C) and cannot be used in combination due to insufficient heat capacity, and a heat storage tank capable of storing hot water at 20 to 30°C is required separately from the cold storage tank.

Also, in order to eliminate the above-mentioned drawbacks, it is possible to use both the cold storage tank and hot water storage, but with this configuration, the power and capacity of the refrigerator must be overestimated by that amount, After all, installation costs and operating costs will be high.

For this reason, a heating and cooling system that uses cold storage and heat storage sources obtained using nighttime electricity as thermal energy for heating and cooling operations during the day is advantageous from the standpoint of both heating and cooling costs and leveling out electricity usage. Despite meeting social demands, the current situation is that there has been little progress in converting from air-conditioning and heating systems that operate only during the day.

Next, for reference, let's examine the problem of air-conditioning systems that perform air-conditioning operations only during the day from the perspective of compression efficiency.Heating operation using a heat pump during winter heating requires that the evaporation temperature of the outside air heat source be below minus, e.g. When the outside temperature is 15℃, the evaporation temperature of the heat pump system (-1O℃
), and since the heated water temperature needs to be 50°C, the condensation temperature is 55°C, and the difference between the two is Δt 85°C, requiring a high compression ratio. On the other hand, during summer cooling, the evaporation temperature of the cooling system is 15°C, and the air cooling condensation temperature is 40°C, and the difference therebetween is Δt 45°C, so the compression ratio is smaller than during winter heating.

Therefore, when comparing the power when a single-stage compressor is used in the above-mentioned heating and cooling system, under the above conditions, the heating power is more than 20% greater than the cooling power, so the power of the refrigerator is the maximum compression ratio of the heat pump. As a result, the power factor of the compressor during cooling will decrease, resulting in an extra yearly contract and additional electricity costs.
Furthermore, there is a risk that excessive power will be generated due to power imbalance due to unbalanced compression ratio.

The present invention eliminates the drawbacks of the prior art, reduces costs by using late-night electricity, and uses latent heat for both cooling and heating, thereby reducing the size of the entire system. The objective is to provide a heating and cooling system that increases volume and significantly reduces construction costs. Another object of the present invention is to integrate the cold storage tank and the heat storage tank so that they can be used for both cold storage during cooling and heat storage during heating. The above-mentioned integrated cold storage/thermal tank is installed on the rooftop ring.
The object of the present invention is to provide an air-conditioning and heating system that can be installed as a single unit and packaged, and as a result, the volume is further reduced, piping work costs are reduced, and pump power and other operating costs are reduced.

"Means for Solving Problems" In order to achieve the above technical problem, the first invention aims to utilize a cold storage/heat storage source obtained using nighttime electricity as thermal energy for daytime air conditioning/heating operation. We propose an air conditioning/heating system characterized in that the thermal energy is stored as ice tank heat during summer cooling, and as latent heat around normal temperature of 15 to 30° C. during winter heating.

That is, according to the present invention, for example, when a heat storage tank capable of storing latent heat near room temperature of at least 10 to 30° C. is used as a heat storage tank of a heat pump device, and when the device performs winter heating, first, an outside air heat source is used. The heat pump is operated in a low-stage compression mode at night, and the heat energy is stored in the heat storage tank as latent heat near normal temperature, and during the day, the heat pump is operated in a high-stage compression mode using the thermal energy as a heat source. It is configured as a heating system that performs two-stage compression operation depending on the time difference.

On the other hand, during summer cooling, the refrigerator is operated mainly at night to store cold by using ice tank heat, and the cooling system is configured such that the thermal energy is mainly used for daytime cooling.

In this case, the ice tank heat used during winter heating is stored.

By filling a cold storage tank that uses ice tank heat, such as a cold storage tank, with a latent heat storage agent that has a melting point near room temperature and is used during winter heating, for example, a latent heat storage agent sealed in a resin capsule. Common use of cold storage and heat tanks will be planned.

The cold storage tank may be constructed by mixing or stacking capsules filled with a latent heat storage agent having a melting point near room temperature and capsules filled with fresh water. In this case, an antifreeze solution is provided between the cold storage tank and the chiller. It is preferable to configure it so that it circulates.

Furthermore, it is also possible to use a Nura water heater to store thermal energy during winter heating, and it is also possible to configure the cold storage heat tank and the Nura water heater to be connected.

Further, in the second invention, in view of the fact that the first invention requires high compression operation even if the compression ratio is low during daytime heating in winter, the outside air heat source is used at night in winter. A two-stage compression operation was carried out at night using a heat pump with a temperature of 40 to 60
An air-conditioning/heating system that stores the condensation temperature on the higher stage of °C as latent heat in a heat storage tank, and performs heating operation using the latent heat during daytime heating, thereby eliminating the need for compression operation during daytime heating in principle. Our goal is to provide the following.

"Function" According to the first invention, in order to store heat as latent heat near normal temperature of 15 to 30°C, especially during winter heating, the heat pump operation using outside air as the heat source is performed in the low-stage compression operation of the two-stage compressor. On the other hand, this heat storage is used as a heat source for the high-stage compressor during the day, and the temperature of the heated hot water used for heating is 5.
Since the temperature is raised to 0°C, it is essentially a two-stage compression operation with a time difference, and the compression efficiency and power cost can be significantly reduced. By using a single rE compressor twice, it is possible to perform two-stage pressure 'mrN rotation even with a single-stage compressor, making it possible to downsize the device.

Further, according to the present invention, since latent heat can be utilized in both winter and summer, it is possible to significantly downsize the heat storage tank especially during winter heating compared to the conventional technology. By filling the cold storage tank used for cooling with a latent heat storage agent with a melting point near room temperature, it becomes possible to perform heating and cooling using the nighttime electricity using a single cold storage tank, resulting in a smaller size. Even if a single cold storage heat tank is installed together with mechanical equipment such as the compressor on the roof of a building, there will be no problem with building strength, significantly reducing construction costs, eliminating the need for pump power for pumping water, Piping can be simplified, and operating costs and maintenance costs can be significantly reduced.

Further, according to the second invention, since there is no need to perform compression operation during daytime heating in principle, in addition to the effects of the first invention, late-night power can be used more effectively, and Similar to the first invention, a single unit compacted by filling a cold storage tank for storing ice latent heat with a member encapsulating a latent heat storage agent having a melting point near the condensation temperature on the higher stage side of the two-stage compression. It became possible to use a cold storage heat tank, and the first
It is possible to achieve the same effect as an invention.

"Embodiments" Hereinafter, preferred embodiments of the present invention will be described in detail by way of example with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, and relative arrangements of the components described in this example are not intended to limit the scope of this invention, but are merely illustrative examples. It's nothing more than that.

FIG. 3 shows a cold storage heat tank 5 used in the present invention. As is well known, in the tank 5, a coiled tube 7 which functions as an evaporator and a condenser is rotatably arranged in a hair bin shape. It is constructed by arranging a spray part 25 on the upper part of the tank 5.

Also, inside the tank 5 is a spherical pole 29 with a diameter of approximately 30 to 60+sm.
The inside of the pole 28 has a melting point of 20 to 2.
Cal 28H20 having a temperature of 2°C and a latent heat of fusion of 35 to 37 kcal/crn' is enclosed.

Incidentally, the above CaC12eH20 may be used alone, or it may be mixed with a catalyst to give a melting point of 20 to 22°C, 25 to 26°C, 2.
The spherical poles 29 formed to have a temperature of 8 to 29°C and filled with such a latent heat agent may be sequentially stacked and arranged in three stages. In this case, fresh water is sprayed from the spray part 25. , is configured to form ice on the outer surface of the coiled tube 7. (
1st embodiment) In addition, fresh water is sealed in the spherical pole 29,
The latent heat agent of Ca11 28H20 may be filled in half into the upper layer and the lower layer, respectively. In this case, the antifreeze solution is sprayed from the spray portion 25. (Second Embodiment) FIG. 1 shows an embodiment of the present invention using such a cold storage heat storage tank 5.

First, to explain the circulation route of fresh water or brine,
21 is a circulation pump that circulates brine made of fresh water or antifreeze, and 4 is a chiller 4 with a built-in heat exchanger.The chiller 4 provides primary cooling through piping 20 connected to the load, a three-way switching valve 27, and a return pipe 23. After the three-way switching valve 28
, and returns to the cold storage heat tank 5 via the piping 24, forming a circulation path during nighttime operation (low stage compression operation) during summer cooling and winter heating.

On the other hand, during daytime operation during winter heating (high-stage compression operation), the pump 22 and the bypass pipe 28 form a circulation path passing through the cold storage heat tank 5 and a circulation path passing through the chiller 4, respectively. The coil tube 7 is made to function as an evaporator on the tank 5 side, and as a condenser on the chiller 4 side.

In addition, 50 is a solar water heater, and the pipe 20 on the outlet side of the circulation pump 21 is branched and connected to the spray part 25, and when heating fresh water or brine in winter, the fresh water or brine is converted into solar hot water with the compressor l. The compressor 50 is used to heat the compressor 50, thereby reducing the load on the compressor 1 and reducing power costs.

Next, to explain the refrigerant circulation system, 1 is a rotary compressor, 2 is an outside air heat source type condenser and evaporator with a built-in heat exchanger 3, a four-way switching valve 17, a three-way switching valve 18, 18, The expansion valves 8, 8-1, 8-2 are connected to the coil tube 7 of the cold storage heat tank 5 and the heat exchanger 6 in the chiller 4 via piping 9-1G, and the four-way switching valve 17 and the three-way Switching valve 18.
19 as appropriate to configure a predetermined refrigerant circulation path to be described later.

The effects based on this configuration will be explained separately for summer cooling and winter heating.

A) During summer cooling A-1) Nighttime thermal energy storage First, the fresh water or brine circulation path of the cold storage heat tank 5 is connected to the pump 21. The bypass pipe 22 provides a bypass, and a refrigeration cycle is configured on the refrigerant side, and ice latent heat is stored in the cold storage heat tank 5.

That is, in the first embodiment, the fresh water circulating in the closed circuit that does not pass through the load side by the bypass pipe 22 is first cooled in the heat exchanger 6 (evaporator) in the chiller 4 to a primary chiller temperature of 0°C or higher, Sprinkling water from the spray part 25 in the cold storage heat tank 5 through the piping 24 cools the coiled tube 7 (evaporator) by immersion, and freezes on the outer surface of the coiled tube 7 at a temperature below the freezing point. do. In this case, the heat storage agent 2 in the capsule
CaC12e)I20 of No. 9 is in a solidified state and is kept cool at 0° C. or lower as sensible heat.

On the other hand, the heat-absorbed refrigerant inside the coil tube 7 is piped! After being compressed by the compressor 1 through the three-way switching valve 18, the four-way switching valve 17, and the three-way switching valve 18, it enters the heat exchanger 3 of the outside air heat source type condenser/evaporator 2, where it is condensed. After that, the fresh water is evaporated and vaporized by the coil tube 7 in the cold storage heat tank 5 and the heat exchanger 6 in the chiller 4 via the expansion valve 88-2, thereby cooling the fresh water. After that, repeat this process to cool the latent heat of the ice and use the spherical pole 29.
Performs sensible heat and cold storage.

In addition, since the outside air temperature at night is lower than the outside air temperature during the day, the electricity cost for the cold storage is low because late-night electricity is used, which requires a lower compression ratio than daytime cooling and is also cheaper.

Further, in the case of the second embodiment, not the antifreeze itself sprayed from the spray portion 25 but the fresh water sealed in the spherical pole 28 is stored as ice latent heat.

A-2) Daytime cooling operation During the daytime, the three-way switching valve 27 is switched to the load side, and the circulation pump 21 is configured to circulate fresh water or brine between the cold storage heat storage tank 5, the load, and the chiller 4, and the compressor 1 is operated during the daytime. make it stop.

And circulation pump 2! By operating the system, the fresh water used for cooling on the load side passes through the return pipe 23, the rechiller 4, and is sprayed directly from the upper part of the cold storage tank 5, where the latent heat of the ice and the sensible heat of the cold water and the spherical pole 29 are mixed. It is repeatedly cooled by the cold storage agent stored during the night, and a predetermined cooling operation is performed.

In this case, by stopping the operation of the compressor 1 during the day, in addition to reducing power costs, it is useful for leveling out power by cutting cooling peaks in the summer.

In addition, the compressor l' is not stopped and the heat exchanger 8 of the chiller 4 is
It is also possible to perform only cooling operation.

That is, after the fresh water or brine cooled in the cold storage heat tank 5 is cooled on the load side, it is primarily cooled by the chiller 4, and then returns to the cold storage heat tank 5 via the three-way switching valve 28 and the piping 24. Secondary cooling is performed by the latent heat of ice formed in the coiled tube 7, and this process is repeated thereafter to perform cooling operation.

Therefore, even in such a case, during daytime cooling, the compressor 1 side is used to perform secondary cooling using the ice latent heat of the fresh water frozen in the cold storage heat tank 5 (on the surface of the coil tube 7 or inside the spherical pole 29). The refrigeration cycle requires cooling only by the chiller 4, and since the chiller 4 performs primary cooling above 0°C,
A low compression ratio is sufficient, and power costs can be significantly reduced.

B) Storage of thermal energy at night during winter heating B- On the other hand, in winter heating operation, the compressor 1 is operated at night by heat pump operation, and the evaporator/condenser 2 is operated by the outside air heat source.
The refrigerant that has absorbed heat by the heat exchanger 3 (evaporator) is compressed by the compressor 1, and then is introduced into the coil tube 7 and the heat exchanger B through the piping 14.15 through the dotted line of the four-way switching valve 17. The heat of condensation is released by the fresh water or antifreeze circulating within 20-24.

Then, the fresh water or antifreeze heated by the heat of condensation is sprayed from the spray part 25, and the spherical pole 2
The above 20
Thermal energy is stored in the normal temperature range including latent heat and sensible heat around ~30°C.

B-2) Daytime heating operation During the day, the three-way switching valve 27 is switched to the load side, and the cold storage heat tank 5
The coiled pipe 7 is used as an evaporator, the heat exchanger 8 on the chiller 4 side is used as a condenser, the three-way switching valve 28 is switched, and the pump 21 and the bypass pipe 2B are used to cool the cold storage heat tank 5.
A circulation path passing through the chiller 4 and a circulation path passing through the chiller 4 are formed separately.

With the above configuration, thermal energy including latent heat and sensible heat of about 20 to 30°C accumulated during the nighttime operation is used as a heat source to heat the fresh water or antifreeze in the circulation path that circulates with the heating load on the chiller 4 side. The heat pump cycle is configured to heat the room to around 50℃, which is required for heating, and heating operation is possible with compression operation at a low pressure ratio.Therefore, it is a two-stage compression operation with a time difference that efficiently utilizes late-night electricity with low electricity costs. This greatly reduces daytime power consumption, enables power leveling, and reduces overall power costs.

FIG. 2 shows another embodiment using a two-stage compressor of the pound pound type.

The two-stage compressor is a low-stage compressor 1-1 and a high-stage compressor 12.
The discharge pipe 33 on the low stage compressor 1-1 side is connected to the cold storage heat tank 5.
On the other hand, the outlet side of the coiled tube 7 is branched and connected to the suction tube 14 on the high-stage compressor 1-2 side, and the heat inside the chiller 4 via the expansion valve 8-2. They communicate with the exchanger 6, respectively. Also, the discharge pipe 9 on the high-stage compressor 1-2 side is connected to the chiller 4.
It communicates with the other end of the heat exchanger 6 inside.

In this embodiment, the same effect as in the first embodiment can be obtained, but since the high-stage compressor 1 with a small piston displacement is used during daytime operation during winter heating, the compression efficiency and power are reduced. Balance will further improve.

FIG. 4 shows an embodiment of the second invention, which has almost the same configuration as the embodiment shown in FIG. 1, so the explanation will focus on the differences from FIG. 1. 28° spherical pole filled in 5° heat storage tank
A heat storage agent mainly composed of paraffin with a melting point of around 55° C. is sealed inside the compressor, and a compound-type two-stage compressor is used as the compressor 1°.

In such an embodiment, during summer cooling, the first
Thermal energy storage during the night and cooling operation during the day are carried out in exactly the same manner as in the embodiment.

On the other hand, during winter heating, first, the heat pump operation of the thermal energy storage two-stage compressor is performed at night, and the refrigerant that has been absorbed by the heat exchanger 3 (evaporator) of the evaporator/condenser 2 by the outside air heat source is transferred to the compressor 1. After being compressed in two stages, it is introduced into the coiled pipe 7 of the heat storage tank 5, and the condensation heat of around 60°C is sealed in the spherical pole 29' through fresh water or antifreeze that circulates in the pipes 20 to 24. The heat is transferred to the paraffin, liquefies the paraffin, and stores thermal energy including latent heat and sensible heat around 50 to 60°C.

In the daytime heating operation, the three-way switching valve 27 is switched to the load side during the day, and the circulation pump 21 is configured to circulate fresh water or brine between the cold storage heat tank 5, the load, and the chiller 4, and the two-stage compressor l By operating the circulation pump 21 in a stopped state, heating operation is performed by heat exchange between the heat storage agent 29' and the heating load using fresh water or antifreeze as a heat medium.

Therefore, in this embodiment, during winter heating as well as during summer cooling, the compressor is not used during the day, and only late-night power can be used, making it possible to use late-night power even further.

"Effects of the Invention" As described above, both the first and second inventions allow the use of latent heat in both winter and summer, so the heat storage tank, especially during winter heating, can be used significantly compared to the conventional technology. It is possible to downsize and install the heat storage tank on the roof instead of underground.
Significant reduction in construction costs.

It is possible to eliminate the need for pump power for pumping water, simplify piping, etc., and significantly reduce operating and maintenance costs.

Also, according to the present invention, it is possible to integrate the heat storage tank with the cold storage tank used for summer cooling, which enables further downsizing, and the cold storage heat tank of the chain wheel can be used for the compressor, etc. Even if it is installed on the roof of a building along with mechanical equipment, there will be no problem of exceeding the strength of the building, and existing buildings can be easily remodeled.

Further, according to the present invention, since the heat storage tank is made smaller, it becomes easier to put into practical use an air-conditioning system that performs substantial two-stage compression operation through a time difference, and as a result, compression efficiency and power cost are reduced. It has become possible to significantly reduce the

Furthermore, according to the second aspect of the invention, there is no need to operate the compressor during daytime cooling and heating in both winter and summer, and late-night power can be used more effectively.

It has various effects such as

[Brief explanation of the drawing]

FIG. 1 is a schematic illustration of a heating and cooling system according to an embodiment of the first invention, FIG. 2 is a schematic illustration of a heating and cooling system according to another embodiment, and FIG. 4 is a heating and cooling system according to an embodiment of the second invention. A schematic explanatory diagram of the system, FIG. 3 is a schematic sectional view of a cold storage heat tank used in each of the above embodiments. Procedural amendment (voluntary) July 4, 1985

Claims (1)

[Scope of Claims] 1) In a heating and cooling system that uses a cold storage/heat storage source obtained using nighttime electricity as thermal energy for heating and cooling operation during the day, the thermal energy is stored as ice latent heat during summer cooling; A heating and cooling system characterized in that heat is stored as latent heat around room temperature of 10 to 30°C during heating in winter.2) A heat pump having a heat storage tank capable of storing the thermal energy as latent heat around room temperature of at least 10 to 30°C. The device performs low-stage compression operation of a heat pump that uses outside air as a heat source at night, stores the thermal energy in the heat storage tank as latent heat near room temperature, and operates the heat pump using the thermal energy as a heat source during the day. The heating and cooling system according to claim 1, characterized in that the heating and cooling system operates in a high-stage compression mode and performs a two-stage compression mode based on a time difference. The heating and cooling system according to claim 1 or 2, characterized in that the heating and cooling system stores cold and the thermal energy is mainly used for cooling during the daytime. 5) A heating and cooling system according to any one of claims 1 to 3, characterized in that the latent heat storage agent is filled with a member encapsulating a latent heat storage agent having a melting point in the vicinity of 5) A resin-based capsule containing the latent heat storage agent 6) The air conditioning system according to any one of claims 1 to 4, characterized in that the cool storage tank is filled with latent heat storage having a melting point near normal temperature. The heating and cooling system according to any one of claims 1 to 5, characterized in that capsules encapsulating an agent and capsules encapsulating fresh water are mixed or stacked and filled in a cold storage tank. 7) The air conditioning system according to any one of claims 1 to 6, characterized in that antifreeze is circulated between the cold storage tank and the chiller. 8) The cold storage thermal tank and the solar water heater. 9) A method for operating a refrigeration and heat pump according to any one of claims 4 to 7, characterized in that In a heating and cooling system, the thermal energy is stored as ice latent heat during summer cooling, and during winter heating, a two-stage compression operation is performed at night using a heat pump using an outside air heat source. A heating and cooling system characterized in that the high-stage condensation temperature of 40 to 60°C obtained during operation is stored as latent heat in a heat storage tank, and during daytime heating, the latent heat is used to perform heating operation. 10) Ice latent heat The heating and cooling system according to claim 9, wherein a member enclosing a latent heat storage agent having a melting point near the condensation temperature on the high stage side is filled in a cold storage tank for storing cold.