JPS6157985B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating device that utilizes waste heat from freezing and refrigeration.

For example, large-scale retail stores called supermarkets handle large quantities of fresh and frozen foods, so they are equipped with freezing and refrigeration equipment, and are also equipped with air conditioning equipment to air-condition the store. is normal. Conventionally, in such stores, freezing and refrigeration equipment and air conditioning equipment were installed independently, and waste heat from freezing and refrigeration was radiated to the atmosphere, while when heating was performed using a heat pump, evaporation heat was absorbed from the atmosphere. It was composed of However, in such equipment configurations, when performing heating, the evaporation temperature of the refrigerant in the evaporator (evaporation coil) that constitutes a part of the heat pump is
In order to keep the temperature difference with the atmosphere above a certain level, the temperature must be set to a low temperature of, for example, -5 to -10 degrees Celsius, so the temperature difference between the condensing temperature and the evaporation temperature becomes large. has a high compression ratio,
This has led to problems such as a considerable increase in power consumption.

Conventionally, therefore, a heat dissipation coil is interposed between the discharge port of a refrigeration or refrigeration compressor and a condenser connected to the discharge port, and the heat dissipation coil is placed, for example, in an air conditioning duct. The interior of the store is heated by heating.
However, in order to sufficiently heat the inside of a store using waste heat from freezing or refrigeration, the condensing temperature of the refrigerant must be raised considerably (e.g. 40 to 50 degrees Celsius), so even if heating is performed only during the daytime, the required power will be reduced. There are problems such as increasing the size of the compressor, resulting in increased power consumption, and the need to increase the compression ratio to increase the condensing temperature, which shortens the service life of the compressor. The current situation is that the capacity of refrigeration equipment is not very large, and part of the total heat required for heating is used as waste heat from refrigeration, and the insufficient amount of heat is supplemented by other heat sources for heating.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a heating device that can effectively utilize waste heat from freezing and refrigeration and reduce power consumption.

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows the principle of an embodiment of the present invention. First, the system for air conditioning or heating will be explained. An air conditioning compressor 1 is connected to the discharge port side via a four-way switching valve 2. An air conditioning coil 3 is connected to the air conditioning coil 3, and a liquid receiver 6 is connected to the air conditioning coil 3 via a check valve 4 and a condensing valve 5. The condensing temperature Tc of the product name)) is set to a predetermined temperature required for heating, and the air conditioning coil 3
The condensed and liquefied refrigerant is made to flow into the receiver 6 by dissipating sensible heat and latent heat. A heat exchange coil 8 provided in an accumulator 7 is connected to the liquid receiver 6 via a check valve 9, and the heat exchange coil 8 is connected to a heat recovery coil 11 via an expansion valve 10. Further, the heat recovery coil 11 is connected to a suction pressure valve 13 via a check valve 12 and the four-way switching valve 2. The heat recovery coil 11 is arranged in a predetermined duct 14, and as described later, it exchanges heat with the refrigeration and refrigeration side heat radiation coils similarly arranged in the duct 14 through the air. The evaporation temperature Te of the refrigerant is set to a predetermined upper limit temperature by the suction pressure valve 13. The suction pressure valve 13 is connected to the accumulator 7 and the accumulator 7 is connected to the suction port side of the air conditioning compressor 1. Therefore, in the accumulator 7, the expansion valve 10 and the heat recovery coil The liquid refrigerant in the heat exchange coil 8 is cooled by the refrigerant evaporated through the refrigerant 11, and at the same time, the temperature of the intake gas of the air conditioning compressor 1 is raised. In addition, the outflow side pipe line of the heat exchange coil 8 branches in the middle and is connected to a liquid supercooling heat exchanger 16 via an expansion valve 15, so that the refrigerant on the freezing and refrigerating side is supercooled here. and its liquid supercooling heat converter 16
is connected to the suction pressure valve 13.

Next, the refrigeration system and the refrigeration system will be explained. A heat exhaust coil 18, a condensing pressure valve 19, and a condenser 20 are sequentially connected to the discharge port side of the refrigeration compressor 17. The heat exhaust coil 1
8 is placed near the heat recovery coil 11 in the duct 14, and sets the temperature of the hot gas to a predetermined temperature tc with the condensing pressure valve 19, and transfers the heat of the hot gas to the air flowing in the duct 14. The heat of evaporation is given to the refrigerant gas in the heat recovery coil 11 through the heat recovery coil 11. The condenser 20 is connected to a liquid receiver 21, and a liquid supercooling coil 22 disposed in the liquid supercooling heat exchanger 16 is connected to the liquid receiver 21. The cooling coil 22 is connected to the suction port side of the refrigeration compressor 17 via an expansion valve 23 and a cooling coil 24 in this order.

On the other hand, the refrigeration system is configured similarly to the above-mentioned refrigeration system, and a heat recovery coil 11 in the duct 14 is disposed on the discharge port side of the refrigeration compressor 25.
A heat exhaust coil 26 disposed near the hot gas and a condensing pressure valve 27 for setting the temperature of the hot gas to a predetermined temperature tc' are connected in sequence, and the condensing pressure valve 27 is connected to the liquid receiver via a condenser 28. 29
Further, a liquid supercooling coil 30 disposed in the liquid supercooling heat exchanger 16 is connected to the liquid receiver 29, and the liquid supercooling coil 30 is connected to an expansion valve 31. and cooling coil 32
It is connected to the suction port side of the refrigeration compressor 25 through sequentially.

Figure 2 shows the air conditioning coil 3, heat recovery coil 11, duct 14, heat exhaust coils 18,
26 and each condenser 20, 28, etc., and is a schematic diagram showing an example of the arrangement position of the air conditioning coil 3.
is housed in a package cage 34 installed in the sales floor 33, which is a heated room.
An air conditioning duct 35 is connected to the air conditioning duct 35, and the air inside the sales floor 33 is circulated through the air conditioning duct 35 by a fan 36 to heat the interior of the sales floor 33. Further, the duct 14 accommodating the heat recovery coil 11 and each of the heat exhaust coils 18 and 26 is disposed in a machine room 37, and a fan 38 provided in the duct 14 is used to cool the machine room 37.
7 is made to flow through the duct 14 from the heat exhaust coils 18 and 26 side toward the heat recovery coil 11 side. Further, the machine room 37 and the air conditioning duct 35 are connected by a communication duct 39, and the warm air in the machine room 37 is transferred to the air conditioning duct 35 through a one-way damper 40 and a fan 41 provided in the communication duct 39. In other words, the sales floor 33 and the machine room 37 are connected by a return duct 42, and the air in the sales floor 33 is fed into the return duct 42 by a fan 43 and a one-way damper 44. It is configured to be returned into the machine room 37 via. Therefore, the heat recovery coil 11 and each heat exhaust coil 18, 2
A circulating air supply path is formed between the machine room 37 in which the air conditioner 6 is arranged and the sales floor 33. Note that each of the condensers 20 and 28 is installed outdoors to absorb condensation heat from the atmosphere. Further, a ventilation fan 45 is attached to the machine room 37, and is configured to activate the ventilation fan 45 to take outside air into the machine room 37 when the outside air temperature becomes higher than the inside of the machine room 37 during heating. has been done.

Next, to explain the operation of the above device, first, each condensing pressure valve 19, 27 on the freezing side and the refrigeration side
are set so that the hot gas temperatures tc and tc' are higher than the outside air temperature in winter by a certain degree, and the compression ratios of the refrigeration and refrigeration compressors 17 and 25 are not too high (for example, 15 to 20 degrees Celsius). death,
On the other hand, the condensing pressure valve 5 on the air conditioning side is set so that the temperature of the hot gas in the air conditioning coil 3 is the temperature required for heating (for example, 40 to 45 DEG C.). In this case, if the heat of evaporation of the refrigerant on the air conditioning side is absorbed from the atmosphere like in conventional equipment, it is necessary to assume that the outside air temperature in winter is around 0°C, so the evaporation temperature of the refrigerant should be around -5 to -10°C. However, in the above device, the air flowing around the heat recovery coil 11 is set to a low temperature of the heat exhaust coil 1.
8 and 26, the suction pressure valve 13 on the air conditioning side can be set so that the suction gas temperature is about 10°C.

After setting each of the valves 5, 13, 19, and 27 as described above, when each compressor 1, 17, and 25 is started, first, the refrigerant gas compressed by the air conditioning compressor 1 flows through the four-way switching valve 2. The refrigerant gas reaches the air conditioning coil 3 via path D-E, and in this case, the refrigerant gas is heated to the temperature Tc set by the condensing pressure valve 5, and
The air-conditioning coil 3 radiates sensible heat and latent heat to the air flowing around it, condenses and liquefies the air, and as a result, the inside of the sales floor 33 is heated. A part of the liquefied refrigerant is transferred to the heat exchange coil 8 in the accumulator 7.
to the expansion valve 10, where it is decompressed and expanded,
At that time, the heat exhaust coils 18, 26 on the freezing and refrigeration side
Since the temperature of the refrigerant gas inside has been raised to the temperature tc, tc' set by the condensing pressure valves 19, 27, the waste heat from the freezing and refrigeration side is absorbed as heat of evaporation by the heat recovery coil 11 and is then inhaled. It evaporates at a temperature Te set by the pressure valve 13. Then, the vaporized refrigerant gas reaches the suction pressure valve 13 via the flow path C-S of the four-way switching valve 2, and then supercools the liquid refrigerant in the heat exchange coil 8 in the accumulator 7, and at the same time slightly raises the temperature. The air is then sucked into the air conditioning compressor 1. On the other hand, the other part of the liquid refrigerant supercooled in the heat exchange coil 8 passes through the other expansion valve 15 and evaporates in the liquid supercooling heat exchanger 16. 16, and the vaporized refrigerant flows through the suction pressure valve 13 and the accumulator 7.
The air is sucked into the air conditioning compressor 1 through the air conditioning compressor 1.

Further, the refrigerant gas compressed by the refrigeration compressor 17 and heated to the temperature tc set by the condensing pressure valve 19 is liquefied after condensing and dissipating heat in the heat exhaust coil 18, and is supercooled by outside air in the condenser 20. It reaches the liquid receiver 21. Then, the liquefied refrigerant is supercooled by the liquid supercooling coil 22 provided in the liquid supercooling heat exchanger 16, and then evaporated through the expansion valve 23 and the cooling coil 24, and then evaporated into the refrigeration compressor 17. is inhaled.

Furthermore, the condensing pressure valve 27 in the refrigeration compressor 25
The refrigerant gas compressed to the temperature tc′ set in
After condensing and dissipating heat in the heat exhaust coil 26, the liquid refrigerant is liquefied, supercooled by outside air in the condenser 28, and supercooled by the liquid supercooling coil 30. The liquid refrigerant passes through the expansion valve 31 and the cooling coil 32 and is evaporated. Thereafter, it is sucked into the refrigeration compressor 25.

According to the above device, waste heat from freezing and refrigeration is transferred to each of the waste heat coils 18, 26 and the heat recovery coil 1.
1 to the refrigerant on the air conditioning side,
The evaporation temperature Te of the refrigerant on the air conditioning side can be set much higher (for example, about 10 degrees Celsius) compared to conventional equipment that absorbs heat from outside air, and as a result, the compression ratio decreases, so the power and power consumption required for heating can be reduced compared to conventional equipment. This can be significantly reduced compared to other devices. In addition, since the condensation temperatures tc and tc' of the refrigerant on the freezing and refrigeration side can be set to a relatively low temperature of about 20 to 25 degrees Celsius,
The refrigeration capacity per kW is improved, reducing power consumption, and the lower compression ratio extends the compressor's service life and makes maintenance easier. Furthermore, since the air passing around the heat exhaust coils 18 and 26 is circulated within the sales floor 33 building as shown in Figure 2, when the heating system is turned off at night, the waste heat from freezing and refrigeration can be removed. Since heat can be stored inside the building, the temperature inside the building can be quickly raised to the desired temperature when heating is restarted, and the heating system can therefore start up quickly and reduce energy loss. . Furthermore, if the condensation pressure is increased by the condensation pressure valves 19 and 27 on the freezing and refrigeration side, the temperature of the hot gas will rise,
Accordingly, the amount of exhaust heat, in other words, the amount of heat recovered on the air conditioning side increases, so that the capacity of the heating device can be increased to the maximum in a short time.

Note that if the refrigerant compressed by the air conditioning compressor 1 and further condensed and liquefied is sent to the air conditioning coil 3 via an expansion valve, the above device can be used for cooling purposes. Of course.

As is clear from the above explanation, according to the heating device of the present invention, the waste heat from freezing and refrigeration is applied to the refrigerant on the air conditioning side, so the evaporation temperature of the refrigerant can be considerably increased, and therefore the load is small,
Since it can be operated with a large product coefficient, power consumption can be significantly reduced compared to conventional methods. In addition, the condensation temperature of the refrigerant on the freezing and refrigeration side can be set to a relatively low temperature of about 20°C, which improves the freezing and refrigeration capacity and reduces power consumption.At the same time, the compression ratio can be increased. Since it can be made smaller, the life of the compressor can be extended and maintenance can be made easier. Furthermore, in this invention, the exhaust heat from the constantly operating refrigeration system is sent to heated rooms that are used only during human activities such as when opening a store, through the circulating air supply path. Since exhaust heat can be stored as heat for heating even when it is not particularly needed, such as at night, heat can be recovered more efficiently, and
This can improve the heating start-up. Therefore, according to the heating device of the present invention, it is possible to heat a wide space with a small capacity, and since it is possible to use heat effectively, it is possible to reduce power consumption, etc. .

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing the principle of an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the installation positions of an air conditioning coil, a heat recovery coil, a heat exhaust coil, and a condenser. 1... Air conditioning compressor, 3... Air conditioning coil, 5
... Condensing pressure valve, 6 ... Liquid receiver, 10 ... Expansion valve, 11 ... Heat recovery coil, 17 ... Refrigeration compressor, 18, 26 ... Exhaust heat coil, 19, 27 ...
Condensing pressure valve, 20, 28...Condenser, 25
...Refrigerating compressor.

Claims (1)

[Claims] 1 Connect a heating coil placed in the air supply path into the room to be heated to the discharge port side of the air conditioning compressor, connect a liquid receiver to the heating coil via a condensing pressure valve, and connect the liquid receiver to the heating coil via a condensing pressure valve. A heat recovery coil is connected to the air conditioner via an expansion valve, and the heat recovery coil is connected to the suction port side of the air conditioning compressor, and a discharge port of the refrigeration or refrigeration compressor is connected near the heat recovery coil. A heat exhaust coil is interposed between the heat recovery coil and the condenser, and is arranged so that heat can be exchanged between the heat recovery coil and the condenser, and a condensation pressure is maintained between the heat recovery coil and the condenser. Interpose a valve,
A heating device characterized in that the heat recovery coil and the exhaust heat coil are disposed in a circulating air supply path to the heated room.