JPH0130062B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention operates a condensing unit (refrigeration device) to produce ice and puts the ice into a heat storage tank to cool the water in the heat storage tank. The present invention relates to an ice heat storage device for air conditioning and other systems that perform air conditioning and cooling using chilled water and ice.

BACKGROUND ART Air conditioning systems that use late-night electricity to operate a refrigerator, store cold water and ice in a heat storage tank, and use this for daytime cooling are already well known. In this air conditioning system, the refrigerant (or brine) from the refrigerator is introduced into the heat storage tank through a pipe, and the refrigerant (or brine) pipe is arranged in a coiled or U-shaped meandering shape to function as a cooler. It has a heat storage tank cooling device in which the refrigerant (or brine) that has passed through the cooler returns to the refrigerator again. This heat storage tank cooling device causes ice to form on the outer surface of the cooler fixed inside the heat storage tank, creating a coexisting state of ice and water inside the heat storage tank, but the ice formed on the cooler remains constant. When ice grows to a thickness of 20 to 30 mm, the cooling capacity of the cooler decreases, resulting in a significant drop in ice growth and the drawback that the amount of ice produced cannot be increased. In order to increase the amount of ice produced, it is necessary to periodically peel off the ice that has adhered to the cooler, and operations such as switching the refrigerator to a defrost cycle (removal of frost) are performed, but the disadvantage is that the efficiency of the heat storage tank decreases. It was hot.

In addition, even in ice-making plants, such as plants that supply ice to ice condensers used in nuclear power plants, the actual operating hours for producing ice are limited, and the capacity of the equipment is not fully utilized. There was a problem.

JP-A No. 58-164937 proposes an ice heat storage system that uses outside air below 0°C in winter to form ice blocks in a water storage tank, and stores this ice until summer to use it for cooling. However, it is easy to obtain ice in the winter, and it is more difficult to store ice until the summer, so it cannot be considered an efficient system.

Problems to be Solved by the Invention The purpose of the present invention is to improve the efficiency of the ice heat storage tank and reduce the equipment cost and operating cost of the entire system by increasing the operating rate of the refrigeration equipment, which conventionally had a lot of idle time. It's about letting people know.

Means for Solving the Problems and Their Effects The above-mentioned object of the present invention is to make one condensing unit (a refrigeration system connected to a condenser, compressor, motor, etc.) ice when there is no load, and to make ice when the load is low. This is achieved by making it possible to switch between ice making and cold water production, and only cold water production at maximum load.

In the ice heat storage device according to the present invention, the piping on the refrigerant outlet side of the condensing unit is branched into two, a brine cooler is connected to one side, and a cold water cooler is connected to the other side, and the piping is connected to the refrigerant outlet sides of the brine cooler and the cold water cooler. A refrigerant circulation circuit formed by connecting pipes individually or combined to the refrigerant inlet side of the condensing unit, a brine circulation circuit formed by connecting a brine pump, the brine cooler, and an ice maker, a cold water pump, and the cold water. It consists of a cooler, an ice heat storage tank that receives ice made by the ice maker, and a cold water circulation circuit connected to an air conditioner and other loads.

For example, the refrigerant evaporation temperature in a brine cooler is -30
℃, and set lower than the refrigerant evaporation temperature (for example, 0℃) in the cold water cooler.

The condensing unit operates in a first mode in which the cold water pump is stopped and only the brine pump is operated, and in a second mode in which both the chilled water pump and the brine pump are operated, depending on the size of the air conditioner and other loads.
mode and a third mode in which the brine pump is stopped and only the cold water pump is operated.

According to the above configuration, one condensing unit can operate the ice maker and also produce cold water, so there is no need to install two independent refrigerators as in the past, reducing equipment costs. Ru. Furthermore, since the operating method can be selected according to the load, operating costs can be reduced. Furthermore, by putting ice cubes made by an ice maker into an ice heat storage tank, the packing density of ice can be increased, the same effect as the ice making rate has been improved, and the heat storage efficiency is increased.

Other characteristics and advantages of the invention will become apparent from the following description with reference to the embodiments of the accompanying drawings.

Embodiment FIG. 1 is a circuit diagram representing an ice heat storage device according to the present invention, which circuit includes a condensing unit 1.
A refrigerant circulation circuit 40 consisting of a refrigerant pipe R connected to 0, a brine tank 16 and a brine pump 1
8. Brine circulation circuit 50 consisting of brine piping B connecting brine cooler 12 and ice maker 20
and a cold water circulation circuit 60 consisting of a cold water pipe C connecting a cold water pump 22, a cold water cooler 14, an ice heat storage tank pipe 24, an air conditioner, and other loads 26.

The refrigerant outlet side piping of the condensing unit 10 is branched into two parts, one of which enters the brine cooler 12 and the other of which enters the cold water cooler 14. Preferably, the refrigerant is R-22 and the brine is 50wt% ethylene glycol (or R-11). The evaporation pressure at the expansion valve is adjusted so that the evaporation temperature of the refrigerant when it passes through the brine cooler 12 is -30°C. On the other hand, the evaporation pressure at the expansion valve is adjusted so that the evaporation temperature of the refrigerant when it passes through the cold water cooler 14 is 0°C. The refrigerant outlet pipes of the brine cooler and cold water cooler are connected to the refrigerant inlet side of the condensing unit after merging. These pipes may be individually connected to the condensing unit without merging.

The brine cooled by the brine cooler 12 enters the ice maker 20 to produce ice blocks or ice pieces. Various types of ice makers can be used, but ice makers with a thickness of 3 mm and a width, for example, are recommended to make it easier to fill the heat storage tank.
An ice maker that can produce plate-shaped (flake-shaped) ice of 200 to 250 mm is desirable. As an example, the ice maker 20 shown in FIG. 2 is used in the emergency containment cooling system of a nuclear power plant, and includes a brine inlet 62, a liquid level gauge 64, a brine circulation pump 66, a drip pan 68, An ice discharge port 70 is provided, and ribbon-shaped (flake-shaped) ice 72 is sent out.

In the apparatus shown in FIG. 1, ice cubes made by the ice maker fall into the ice box 28 at the bottom, and are then transported by various ice conveyors 30, such as screw conveyors, bucket conveyors, pneumatic conveyors, etc. Transferred to an ice heat storage tank. If the ice making machine 20 can be attached to the upper part of the ice storage tank 24, the ice blocks can be dropped into the storage tank as they are, and an ice box and an ice conveyor are not required.

The cold water cooled by the cold water cooler 14 is transferred to the ice heat storage tank 2.
4 and is further sucked in by the cold water pump 22 to perform the action of cooling the air conditioner and other loads 26. After cooling the load, the return piping branches into two, one to the cold water cooler 14 and the other to the ice storage tank 24, similar to conventional ice storage systems.

Note that a motor-driven or manual valve is installed in the middle of the piping route for operation control.

The ice heat storage device according to the present invention is configured as described above, and is operated by selecting the following three modes by switching the operating circuit depending on the magnitude of the load on the air conditioner or other equipment.

(1) When there is no load: The chilled water pump is stopped, only the brine pump is operated, the refrigerant circulation circuit and the brine circulation circuit are operated, and only ice is made.

(2) At low load, both the chilled water pump and brine pump are operated to operate the refrigerant circulation circuit, brine circulation circuit, and chilled water circulation circuit to produce ice and chilled water.

(3) At maximum load: Stop the brine pump, operate only the chilled water pump, operate the refrigerant circulation circuit and chilled water circulation circuit, and only produce chilled water.

It is thus possible to perform both ice making and chilled water production with one condensing unit.

Effects of the Invention As explained in detail above, according to the present invention, it is possible to reduce the number of refrigerators, and equipment costs are reduced. Additionally, since the operating method can be selected according to the load, operating costs can be reduced. In particular, by using late-night electricity, it is possible to reduce the equipment capacity and further reduce operating costs by improving the equipment operating rate. Furthermore, as a result of the use of an ice maker, the packing density of ice is increased, and as a result, the thermal efficiency of the ice heat storage tank is increased, and its effects are extremely remarkable.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing the entire ice heat storage device according to the present invention, and FIG. 2 is a perspective view showing an example of an ice making machine. 10... Condensing unit, 12... Brine cooler, 14... Cold water cooler, 18... Brine pump, 20... Ice maker, 22... Cold water pump, 24... Ice heat storage tank, 26... Air conditioner, 40
... Refrigerant circulation circuit, 50 ... Brine circulation circuit,
60...Cold water circulation circuit.

Claims (1)

[Scope of Claims] 1. The refrigerant outlet side piping of the condensing unit is branched into two, a brine cooler is connected to one side, and a cold water cooler is connected to the other side, and the refrigerant outlet side piping of the brine cooler and the cold water cooler are connected to each other. a refrigerant circulation circuit connected to the refrigerant inlet side of the condensing unit, each singly or combined; a brine circulation circuit comprising a brine pump, the brine cooler and the ice maker connected; a cold water pump, the cold water cooler; It is equipped with an ice heat storage tank that receives ice made by the ice maker, and a cold water circulation circuit connected to an air conditioner and other loads, so that the refrigerant evaporation temperature in the brine cooler is lower than the refrigerant evaporation temperature in the cold water cooler. The first mode stops the cold water pump and operates only the brine pump, the second mode operates both the cold water pump and brine pump, and the second mode stops the brine pump, depending on the size of the air conditioner and other loads. An ice heat storage device characterized by being switchable between three operating states including a third mode in which only the cold water pump is operated. 2. The apparatus according to claim 1, wherein the ice maker is installed above the ice heat storage tank, and ice blocks made by the ice maker fall into the ice heat storage tank. 3. The apparatus according to claim 1, wherein the ice making machine is provided with an ice box, and is further provided with an ice conveying machine for transferring ice blocks in the ice box to the ice heat storage tank.