JPH04263723A - Ice heat accumulator - Google Patents

Abstract

PURPOSE:To obtain the above accumulator whereby ice in an aqueous solution is prevented from flowing into an evaporator in a refrigerating machine and highly effective operation is stably performed. CONSTITUTION:A bypass circuit 20, in which one end thereof is connected between a condenser 3 and a first flow control valve 4 and the other end is connected between the first flow control valve 4 and an evaporator 5, is provided, and a heater 22 and a second flow control valve 23 are respectively connected midway on this bypass circuit 20. Furthermore, an ice-detecting means 24 for detecting whether ice exists in the inlet of the heater 22 is provided, and detects the existence of the ice in the inlet of a heater 22. Water or an aqueous solution in a heat-accumulating tank 6 is circulated by a circulating pump 11, and when it is detected at the inlet of the heater 22 that the ice is produced, heat-exchange is done between the water or aqueous solution containing the ice and a refrigerant, and it is heated thereby, following which it is circulated into the evaporator 5.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] This invention relates to an ice heat storage device.
For example, it relates to things used in air conditioning of buildings, etc., and in the production and processing of foods that are cooled and refrigerated at freezing temperatures.

0002

2. Description of the Related Art FIG. 5 is a block diagram showing a conventional ice heat storage device described in, for example, Japanese Patent Application No. 1-229519. In the figure, 1 is a refrigerator, a compressor 2, a condenser 3,
It is equipped with a first flow control valve 4 and an evaporator 5 as main components. 6 is a heat storage tank that stores ice and water, 7 is an aqueous solution containing additives such as potassium or sodium salts that can stably increase supercooling, 8 is ice floating in the aqueous solution 7, and 9 is a release of supercooling. For example, an ice block of a predetermined size is provided near the outlet of the supercooled aqueous solution. 10 is a filter that is an ice removing means for filtering ice 8 in the aqueous solution 7; 11 is a circulation pump that circulates the aqueous solution 7;
A water pipe 2 has one end connected to the heat storage tank 6, and a filter 10, a circulation pump 11, and an evaporator 5 connected in sequence to constitute a circulation path for guiding the aqueous solution 7 cooled by the evaporator 5 to the heat storage tank 6. It is. Note that the aqueous solution 7 may be simply water without adding any additives.

Next, the operation will be explained. The aqueous solution 7 is heated to several degrees below the freezing point (approximately -2℃) by the evaporator 5 of the refrigerator 1.
supercooled to. This aqueous solution 7 passes through a pipe 12 and is broken from its supercooled state by an ice cube 9 of a predetermined size provided above the heat storage tank 6, and becomes small pieces of ice 8 corresponding to the amount of supercooled heat. This ice 8 flows into the heat storage tank 6 together with the remaining aqueous solution 7 that has not turned into ice, and floats on top of the aqueous solution 7 at the freezing point temperature within the heat storage tank 6. The aqueous solution 7 in the lower part of the heat storage tank 6 passes through a filter 10 and is sent to the refrigerator 1 by a circulation pump 11 to form a cycle.

FIG. 6 is a pressure-enthalpy diagram showing the operation of this refrigerator 1. Graph A represents a saturation line, and graph B represents the operation of this refrigerator 1. The operating state changes in the direction of the arrow. In the refrigerator 1, the refrigerant at the outlet of the condenser 3 is a saturated liquid (point C), and the refrigerant at the outlet of the evaporator 5 is a saturated vapor (point C).
The flow rate is controlled by the first flow control valve 4 so that the flow rate reaches point D). The portion of straight line E represents the change in the evaporator 5.

[0005]

[Problems to be Solved by the Invention] The conventional ice heat storage device is constructed as described above, and the ice 8 in the aqueous solution flows into the evaporator 5 of the refrigerator, and this serves as a core, and the ice flows into the evaporator 5. In order to prevent this from occurring inside the device and destroying the device,
An ice filter 10 is provided in a water pipe 12 on the inlet side of the evaporator 5. However, this still has the following problems. (1) Ice crystals are small, ranging from tens of micrometers to hundreds of micrometers, and in order to capture this ice, it is necessary to make the filter of the ice filter quite fine. The flow resistance increases and the power of the circulation pump increases. (2) The filter of the filter becomes clogged, and maintenance is required to prevent the filter from clogging.

The present invention was made to solve the above-mentioned problems, and it prevents the ice 8 in the aqueous solution from flowing into the evaporator 5 of the refrigerator, thereby achieving stable and highly efficient operation. The purpose is to obtain an ice heat storage device that can perform

[0007]

[Means for Solving the Problems] An ice heat storage device according to the present invention is constructed by sequentially connecting a compressor, a condenser, a first flow control valve, and an evaporator, and includes water or an additive added to water. A refrigerator that supercools an aqueous solution, a supercooling release means that releases supercooling of the water or aqueous solution supercooled by the refrigerator and generates ice, and stores the ice and supercooled water generated by the supercooling release means. In an ice heat storage device that includes a heat storage tank, a circulation pump that supplies and circulates water or aqueous solution in the heat storage tank to an evaporator, and a circulation path that connects these in order and circulates the water or aqueous solution, one side is a condenser. A bypass circuit is provided that is connected between the first flow control valve and the other between the first flow control valve and the evaporator, and a heater and the second flow control valve are connected from the condenser side in the middle of this bypass circuit. The device is connected in sequence and includes a detection means for detecting the presence of ice in the water or aqueous solution fed from the heat storage tank to the evaporator, and configured to circulate the water or aqueous solution from the heat storage tank to the heater and the evaporator in order. This is what I did.

[0008]

[Operation] The water or aqueous solution of the ice heat storage device according to the present invention is cooled to a supercooled state of several degrees below freezing in the evaporator of the refrigerator. The supercooled state of this supercooled aqueous solution is released by the supercooling release means in the upper part of the heat storage tank, and ice corresponding to the amount of heat of supercooling is generated. The water or aqueous solution that has not turned into ice is sent from the heat storage tank to the heater of the refrigerator by a circulation pump, where it exchanges heat with a refrigerant that is higher than the temperature of the water or aqueous solution (0°C or higher), until the temperature of the water or aqueous solution reaches +0. After being heated to about 5°C, it flows into an evaporator and is cooled. Ice is accumulated in the heat storage tank while floating in water or an aqueous solution. As a means to prevent ice in water or aqueous solution from flowing into the evaporator of the refrigerator, a heater and a second flow control valve are provided to prevent ice in water or aqueous solution from flowing into the evaporator from the heat storage tank. A detection means for detecting the presence of the heater is provided so that the operating state of the heater can be controlled.

[0009]

[Example] Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an ice heat storage device according to an embodiment of the present invention. In the figure, 20 is a bypass circuit connected between the condenser 3 and the first flow control valve 4 and the other between the first flow control valve 4 and the evaporator 5, and 22 and 23 are the bypass circuits. A heater and a second flow control valve are provided in the middle of the circuit. 24 and 25 are heaters 22
First and second temperature sensors are provided at the inlet and outlet of the aqueous solution, respectively, to detect the temperature of the aqueous solution. These temperature sensors 24 and 25 can detect the presence of ice in the water or aqueous solution fed from the heat storage tank 6 to the evaporator 5. Note that the other configurations are the same as those of the prior art, so explanations will be omitted.

Next, the operation will be explained. The operation of the aqueous solution circulation system is exactly the same as that of the conventional apparatus, and only the operation of the refrigerator 1 is different, so the operation of only the refrigerator 1 will be described. The refrigerator 1 operates in a first operation mode when the temperature of the aqueous solution detected by the first temperature sensor 24 provided at the inlet of the heater 22 is 0°C or higher, and in a first operation mode when the temperature of the aqueous solution reaches 0°C. There is a second operation mode for when the limit is reached, and each operation mode will be explained below.

[0011] In the first operation mode, the first temperature sensor 2
This is the operation when the temperature of the aqueous solution in the pipe 12 detected in step 4 is 0° C. or higher. For example, this mode is entered when starting up the ice heat storage device. FIG. 2 is a pressure-enthalpy diagram showing the operation of the refrigerator in the first operation mode. In this mode, the second flow control valve 23 of the bypass circuit 20 is closed, the gas refrigerant discharged from the compressor 2 is cooled and liquefied in the condenser 3, and the pressure is reduced to a low pressure by the first flow control valve 4. This low-pressure refrigerant flows into the evaporator 5, exchanges heat with the aqueous solution, cools the aqueous solution, becomes a gas, and is sucked into the compressor 2 again. That is, in this first operation mode, the heater 22 does not operate as shown in FIG. The water or aqueous solution is cooled down to several degrees below freezing by the evaporator 5 and returned to the heat storage tank 6 .

When the temperature of the aqueous solution decreases due to operation in the first operation mode and ice nuclei become mixed into the aqueous solution, the first temperature sensor provided at the aqueous solution inlet of the heater 22 At 24, it is detected that the temperature of the aqueous solution has reached 0°C. At this time, the second operation mode is entered. FIG. 3 is a pressure-enthalpy diagram showing the operation of the refrigerator in the second operation mode. In this mode, the second flow control valve 23 of the bypass circuit 20 is opened and the heater 22 is operated as a condenser. The refrigerant gas discharged from the compressor 2 is cooled and liquefied in the condenser 3 to become a saturated liquid. A portion of this liquid refrigerant flows into the bypass circuit 20 and is heated by exchanging heat with water or an aqueous solution in the heater 22. This refrigerant is reduced in pressure to a low pressure by the second flow control valve 23, merges with the refrigerant reduced to low pressure by the first flow control valve 4, and flows into the evaporator 5. Here, the refrigerant exchanges heat with the aqueous solution to cool the aqueous solution, and is sucked into the compressor 2. At this time, the first flow control valve 4 is controlled so that the refrigerant at the outlet of the evaporator 5 is slightly overheated, and the second flow control valve 23
is the second temperature sensor 2 provided at the outlet of the heater 22
The temperature of the aqueous solution detected by 5 is controlled to be approximately +0.5°C. Therefore, in the second operation mode, the 0° C. aqueous solution 7 sent from the heat storage tank 6 by the circulation pump 11 is heated to +0°C where the ice cores are sufficiently melted by the heater 22.
．． After being heated to about 5° C., it is cooled to a supercooled state by the evaporator 5 and returned to the heat storage tank 6. Section F in FIG. 3 is the operating portion by the heater 22.

In this embodiment, ice crystal nuclei do not flow into the evaporator 5 and freeze, allowing stable continuous operation. Furthermore, since the water or aqueous solution is heated by the heat of the refrigerant of the refrigerator 1, the cooling capacity of the evaporator 5 increases. Furthermore, the filter of the conventional device is not required, the power of the circulation pump 11 can be reduced, and highly efficient operation is possible.

Example 2. In the first embodiment, in the first operation mode, the second flow control valve 23 is closed and the bypass circuit 2 is closed.
Embodiment 2 shown in FIG.
In this case, an on-off valve 21 is provided in a bypass circuit 20 between the condenser 3 and the heater 22. According to this second embodiment, in the first operation mode, the on-off valve 21 is closed and the bypass circuit 20 is closed.
By preventing the refrigerant from flowing into the heater 22, in addition to the effects of the embodiments described above, it is possible to prevent the refrigerant from staying inside the heater 22.

In the above embodiment, the heater 22 is installed between the circulation pump 11 and the evaporator 5, but the same effect can be obtained even if the heater 22 is installed between the heat storage tank 6 and the circulation pump 11. There is.

Furthermore, in the above embodiment, the first flow control valve 4 is controlled so that the refrigerant at the outlet of the evaporator 5 is slightly overheated in the second operation mode.
may be controlled so that the outlet refrigerant is slightly supercooled.

Further, in the above embodiment, the first temperature sensor 24 is provided at the entrance of the heater 22, but ice cores may be detected by detecting the amount of light transmitted.

Further, in the above embodiment, the supercooling canceling means is described as an ice block of a predetermined size provided near the outlet of the supercooled aqueous solution, but it may also be a plate-shaped object made of metal such as stainless steel.

[0019]

As described above, according to the present invention, the compressor, the condenser, the first flow control valve, and the evaporator are sequentially connected to each other, and it is possible to filtrate water or an aqueous solution of water with additives. A refrigerator for cooling, a supercooling release means for releasing supercooling of water or aqueous solution supercooled by the refrigerator to generate ice, a heat storage tank for storing ice and supercooled water generated by the supercooling release means, In an ice heat storage device equipped with a circulation pump that supplies and circulates the water or aqueous solution in the heat storage tank to the evaporator, and a circulation path that connects these in sequence and circulates the water or aqueous solution, one side is connected to the condenser and the other is connected to the first flow rate. A bypass circuit is provided that is connected between the control valves and the other is connected between the first flow control valve and the evaporator, and a heater and the second flow control valve are connected in sequence from the condenser side in the middle of this bypass circuit. With,
It is equipped with a detection means for detecting the presence of ice in the water or aqueous solution fed from the heat storage tank to the evaporator, and is configured to circulate the water or aqueous solution from the heat storage tank to the heater and the evaporator in order. By preventing the crystal nuclei from flowing into the evaporator, it is possible to obtain an ice heat storage device that can operate stably and with high efficiency.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an ice heat storage device according to a first embodiment of the present invention.

FIG. 2 is a pressure-enthalpy diagram showing the operation of the refrigerator in the first operation mode according to the first embodiment of the present invention.

FIG. 3 is a pressure-enthalpy diagram showing the operation of the refrigerator in the second operation mode according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram showing an ice heat storage device according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram showing a conventional ice heat storage device.

FIG. 6 is a pressure-enthalpy diagram showing the operation of a refrigerator of a conventional ice heat storage device.

[Explanation of symbols]

1 Refrigeration equipment 2 Compressor 3 Condenser 4 First flow control valve 5 Evaporator 6 Heat storage tank 7 Aqueous solution 8 Ice 9 Supercooling release means 11 Circulation pump 20 Bypass circuit 22 Heater 23 Second flow control valve 24 Ice detection means

Claims (1)

[Claims] Claim 1: A refrigerator configured by sequentially connecting a compressor, a condenser, a first flow control valve, and an evaporator, and supercools water or an aqueous solution of water with additives; A supercooling release means that releases the supercooling of the cooled water or aqueous solution to generate ice, a heat storage tank that stores the ice or supercooled water generated by the supercooling release means, and a heat storage tank that stores the water or aqueous solution in the heat storage tank. An ice heat storage device comprising a circulation pump that supplies and circulates the water or aqueous solution to the evaporator, and a circulation path that connects these in sequence and circulates the water or aqueous solution, one of which is connected between the condenser and the first flow control valve. A bypass circuit is provided in which the other side is connected between the first flow control valve and the evaporator, and a heater and a second flow control valve are sequentially connected from the condenser side to the middle of this bypass circuit, and the heat storage The apparatus includes a detection means for detecting the presence of ice in the water or aqueous solution fed from the tank to the evaporator, and is configured to circulate the water or aqueous solution from the heat storage tank to the heater and the evaporator in order. An ice heat storage device characterized by: