JP4384147B2 - Static ice storage system - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a static ice heat storage system that makes ice on the surface of a cooling coil (brine tube) in an ice heat storage tank, and in particular, operates with an inner melting type that melts ice from the inside during a large daytime load, and outside during a nighttime small load. The present invention relates to a combined ice heat storage system that melts ice from the outside and supplies cold water to the load side to handle small loads.

  There are two types of ice heat storage systems: a static type that makes ice in a heat storage tank, and a dynamic type that pumps sherbet-like ice made in the ice making unit to the ice storage unit. There are an inner melting type that melts ice and an outer melting type that melts ice from the outside of the coil tube. The present invention is a static type ice heat storage system that operates with an inner melting type that melts ice from the inside during daytime heavy loads, and supplies cold water to the load side with an outer melting type that melts ice from the outside during small loads at night. The present invention relates to a composite ice heat storage system that handles a small load. The following technologies are known as static type ice heat storage systems.

Japanese Patent Laid-Open No. 8-152162 “Inner melting ice storage tank” shows a typical structure of a static inner melting ice storage system, and a metal support member is attached to a heat transfer tube (cooling coil). A blower and an air diffuser that send air to the bottom of the ice storage tank are provided to increase the speed of ice storage and to lower the temperature of the ice storage.

In Japanese Patent Laid-Open No. 10-288436 “Static ice making device in ice heat storage system”, a cooling plate extending in the vertical direction is added adjacent to the cooling pipe, and means for spraying water is further added to increase ice making capacity. Yes.

As in the present invention, it operates with an inner melting type that melts ice from the inside during heavy loads in the daytime, and supplies cold water to the load side with an outer melting type that melts ice from the outside during small loads at night to handle small loads. The combined ice heat storage system enables energy-saving and high-efficiency operation, but the temperature of the chilled water supplied to the load side at the start of light load operation at night becomes supercooled below 0 ° C, and the chilled water pump It has been found that there is a possibility that chilling may occur in the cold water pump due to freezing inside the piping on the suction side. If it demonstrates referring FIG. 4 , the brine from a refrigerator (not shown) will be supplied to the cooling coil 12 inside the ice thermal storage water tank 10, and it will ice around a cooling coil. Since it is operated by an inner melting type that melts ice from the inside during a large daytime load, brine is supplied to the large load side to execute a cooling operation. At this time, by releasing the air from the blower 14 into the heat storage tank, the inside of the water tank is agitated, and a lower temperature brine can be sent to the large load side.

  On the other hand, at the time of a light load at night, the cold water pump 16 is operated to take out cold water from the position B near the bottom of the water tank and supply it to the small load E through the cold water pipe 18 and the on-off valves 20, 21, 22 to save energy. Cooling operation of the type is performed. Air mixed in the pipe is sent to the air vent valve C. The reflux water that has finished the cooling operation is returned from the cold water inlet A into the heat storage tank 10.

  Such a small load operation reaches a steady state after about 2 hours from the start of operation, and a stable operation is possible. However, when the small load operation is started, a part of the water in the heat storage tank is supercooled. Since it is in a state (less than 0 ° C.), the supercooling water around the cooling coil 12 flows in the diagonal direction, and the supercooling water flows into the cold water pipe 18. The supercooled water undergoes a physical change at the position of the on-off valves 20 and 21 to cancel the supercooled state and freezes. If freezing occurs here, the suction-side pipe line of the cold water pump 16 is closed, and a phenomenon such as cavitation occurs in the cold water pump 16 so that the stable operation cannot be performed, and the heat exchanger (not shown) that handles the load becomes unusable. It was found that not only the supply of cold water could be disabled, but also abnormal noise and piping damage could occur.

The main object of the present invention is to prevent the cooling water supply pipe from being frozen by supplying supercooling water when performing an externally melted cold water supply operation for processing a small load at night, and providing a stable cold water supply. It is to enable driving.
Another object of the present invention is to realize an energy-saving ice heat storage system by enabling a combined operation of an inner melting type and an outer melting type.

  In order to solve the above-described problems, in the first aspect of the present invention, a chilled water pipeline and a chilled water pump for processing a nighttime small load are arranged, and a tank chamber is provided at a side portion in the ice heat storage water tank. The tank chamber is provided with an outlet pipe on one side, a water tank water suction port on the other side, and a bypass pipe connection port at a position adjacent to the suction port. Water in the water tank is supplied from the outlet pipe to the cold water. An outlet pipe for supplying the pipe, a reflux pipe for introducing cold water after the small load treatment from the cold water pipe to the inlet opening of the water tank, and cold water from the middle of the reflux pipe in the chamber in the tank. A static ice heat storage system is provided, comprising: a bypass conduit that flows into the bypass conduit connection port.

  In the ice heat storage system of the present invention, a tank chamber is provided on the side of the water tank and an outlet pipe is disposed on one side thereof, and cold water from the bypass pipe is introduced into the tank chamber to reduce the temperature of the water tank. By mixing with cold water, water having a temperature relatively higher than the temperature in the water tank is supplied to the cold water supply pipe, eliminating the possibility of supplying supercooled water to the cold water supply pipe. Thus, it is possible to stably carry out the small load operation at night.

As a further preferred aspect of the present invention, a temperature sensor that detects a temperature of cold water from the outlet pipe, and a control that controls the flow rate of the reflux pipe line and the flow rate of the bypass pipe line based on a signal from the temperature sensor. And the control unit can control so that the temperature of the cold water from the outlet pipe is 0 ° C or higher, and preferably around 1 ° C. Thereby, when the temperature in a water tank is 1 degreeC or more, there is no amount of bypass, and it becomes possible to further reduce the increase in the energy consumption of a cold water pump.

According to another preferred embodiment of the present invention, a resistor can be provided in the bypass line so that the flow rate of the bypass line is in the range of 25 to 40% of the flow rate of the outlet line. It is possible to reduce the amount of bypass, and to reduce the capacity of the chilled water pump and the increase in energy consumption.

  1 and 2 show the most preferable embodiment of the static ice heat storage system according to the present invention, and brine from a refrigerator (not shown) is supplied to the cooling coil 12 inside the ice heat storage water tank 10, Freezes around the cooling coil. When the daytime is a heavy load, it is operated by an inner melting type that melts ice from the inside, and brine is supplied to the large load side to execute a cooling operation. Although omitted in FIG. 1, by releasing air from the blower 14 as shown in FIG. 3 into the heat storage tank, the inside of the water tank is agitated, and lower temperature brine can be sent to the large load side. .

  The ice heat storage system of the present invention is a composite ice heat storage system that supplies cold water to the load side and processes the small load by an external melting type that melts the ice icing around the cooling coil 12 from the outside when the load is small at night. Therefore, a circuit for processing a small load is provided. That is, a chilled water pipe 30 and an externally melted chilled water pump 32 for processing a small load at night are arranged, and chilled water is sent to the water / water heat exchanger 36, and the night load side through the heat exchanger 36. Is supplied with cold heat. Flow control valves 34 and 57 and a temperature sensor 62 are provided so as to make the supply temperature to the night load side constant.

  In accordance with the characteristics of the present invention, a tank chamber 40 made of a heat insulating material is provided at a side portion in the ice heat storage water tank 10. The tank chamber 40 has an outlet pipe 42 on one side, a water tank water suction port 44 on the other side, and a further suction. A bypass pipe connection port 46 is provided at an opposed position in the vicinity of the port 44, and the other surfaces are sealed. As an example, the width W of the in-vessel chamber 40 can be set to 3000 mm, the height H to 450 mm, the depth D to 180 mm, and the suction port height S to 500 mm. In FIG. 1, the tank chamber 40 is installed horizontally along the inner wall surface at the bottom of the ice heat storage tank 10, but the tank chamber 40 may be installed standing up along the inner wall surface as a vertical shape. it can.

  An outlet pipe 50 for supplying the water in the water tank to the cold water pipe 30 is connected to the outlet pipe 42 of the tank chamber 40. Furthermore, the cold water after the small load treatment is introduced from the cold water pipe 30 to the inlet opening 11 of the water tank 10, the flow control valve 53, and the cold water is supplied from the middle of the reflux pipe 52 to the bypass pipe of the in-chamber chamber 40. A bypass conduit 54 and a flow rate control valve 55 are provided to flow into the passage connection port 46.

  Thus, according to the basic aspect of the ice heat storage system of the present invention, the cold water from the bypass pipe 54 is introduced into the tank chamber 40 provided in the ice heat storage water tank 10, and the cold water in the water tank is cooled. As a result of mixing, water having a temperature relatively higher than the temperature in the water tank is supplied to the cold water supply pipe 30, eliminating the possibility of supplying supercooled water to the cold water supply pipe 30 at night. It is possible to stably perform the small load operation.

FIG. 3 shows another preferred embodiment of the present invention in which a resistor 58 (throttle, orifice, manual valve, etc.) is provided in the middle of the bypass line 54. This resistance is preferably set so that the flow rate passing through the bypass line 54 is in the range of 25 to 40% of the flow rate of the outlet pipe. As a result, a wasteful amount of bypass can be reduced, and an increase in the capacity and energy consumption of the chilled water pump can be reduced.

  As described above, the object of the present invention is to prevent the supercooled water from being supplied to the chilled water supply circuit. Therefore, as an optimal mode, the chilled water temperature of the outlet pipe 42 of the tank chamber 40 is detected. Therefore, a control unit 70 can be provided which controls the flow rate of the reflux line 52 and the flow rate of the bypass line 54 based on a signal from the temperature sensor 60. The control unit 70 controls the temperature of the chilled water from the outlet pipe 42 to be 0 ° C. or higher, and preferably near 1 ° C. In addition, the control unit 70 outputs a signal from the temperature sensor 62 provided at the cold water supply position to the small load side. Based on this, the flow control valve 57 of the chilled water supply circuit can be controlled so that the optimum chilled water is supplied to the small load side.

  As described above in detail, according to the present invention, when performing an externally melted chilled water supply operation to handle a small night load, supercooled water is supplied to the chilled water supply pipe and freezes. Thus, a stable cold water supply operation is possible, and an energy-saving ice heat storage system is realized. Furthermore, the technical effect is extremely remarkable, such as an increase in energy consumption of the cold water pump can be minimized.

Schematic showing the ice thermal storage system by this invention. The schematic perspective view showing the chamber in a tank in the present invention. Schematic showing the ice thermal storage system by this invention. Schematic showing the conventional ice thermal storage system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ice thermal storage tank 11 Inlet opening 12 Cooling coil 30 Chilled water pipe 32 Chilled water pump 34,53,55,57 Flow control valve 40 In-chamber chamber 42 Outlet pipe 44 Suction port 46 Bypass pipe connection port 50 Outlet pipe 52 Reflux pipe 54 Bypass line 58 Resistance 60 Temperature sensor 70 Control unit

Claims (3)

A static ice heat storage system that makes ice on the surface of the cooling coil in the ice heat storage water tank. It operates with an internal melting system that melts ice from the inside during daytime heavy loads, and an external melting system that melts ice from the outside during small nighttime loads. A combined ice heat storage system that supplies cold water to the load side to handle small loads,
Chilled water pipes and chilled water pumps are arranged to handle small loads at night,
A tank chamber is provided on the side of the ice heat storage water tank,
This tank chamber is provided with an outlet pipe on one side, a water tank water suction port on the other side, and a bypass pipe connection port at a position adjacent to the suction port,
An outlet pipe for supplying water in the water tank from the outlet pipe to the cold water pipe;
A reflux line for introducing cold water after the small load treatment from the cold water line to the inlet opening of the water tank;
A static ice heat storage system comprising: a bypass pipe for allowing cold water to flow into the bypass pipe connection port of the in-tank chamber from the middle of the reflux pipe.   A temperature sensor that detects a temperature of the cold water from the outlet pipe, and a control unit that controls a flow rate of the reflux pipe and a flow rate of the bypass pipe based on a signal from the temperature sensor, and the outlet pipe 2. The static ice heat storage system according to claim 1, wherein the control unit controls the temperature of the cold water from the temperature to 0 ° C. or higher, preferably about 1 ° C. 3. The static ice heat storage system according to claim 1, wherein a resistance is provided in the bypass pipe so that a flow rate of the bypass pipe is in a range of 25 to 40% of a flow rate of the outlet pipe.

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