JPS6346343B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solar heat collecting device that prevents flashing and freezing, and protects equipment within the system from corrosion.

In a solar system, a flashing (boiling) phenomenon may occur in the heat collector during periods when the amount of heat collected is large and the load is low, such as the mid-season, and during periods when the amount of heat collected is large and the load is low, such as during the summer and holidays during the mid-season. When this flushing occurs, retained water becomes concentrated and scale deposits occur, reducing the efficiency of the system and making it more susceptible to damage due to corrosion. The same applies to freezing, and if this occurs, it will lead to a serious accident.

The present invention has been made to prevent flashing and freezing in this solar system, as well as to prevent corrosion.

The present invention will be specifically explained according to the embodiment shown in the drawings. In the drawings, 1 is a group of solar heat collectors (hereinafter referred to as collectors), 2 is a heat storage tank,
Reference numeral 3 indicates a circulation pump, 4 indicates an outflow channel, and 5 indicates a return channel, and the collector 1 is arranged at the same height as the heat storage tank 2 or at a lower level. A circulation channel is formed between the collector 1 and the heat storage tank 2 by an outflow channel 4 and a return channel 5. A nitrogen gas introduction pipe 6 is connected to the return channel 5; A return water tank 7 is connected.

The nitrogen gas introduction pipe 6 is for receiving a supply of low pressure nitrogen gas from the low pressure nitrogen supply device 8 and pressurizing it into the system. The low pressure nitrogen supply device 8 is a high pressure
Consisting of an N ₂ cylinder 9, a low pressure container 10, a group of pressure control devices, etc., nitrogen is stored in the low pressure container 10 while maintaining a predetermined low pressure, and is transferred to the inlet pipe 6.
It is designed to supply water at a constant pressure. In addition,
11 indicates an automatic air bleed valve.

The return water tank 7 is installed at a lower level than the collector 1, and a solenoid valve 13 is interposed in a connecting path 12 with the outgoing pipe line 4. And this return water tank 7 and heat storage tank 2
A pipe line 14 is provided to connect the two, and a return water pump 15 is interposed in this pipe line 14. A liquid level controller 16 is also attached to the return water tank 7. The connection position of the return water tank 7 to the outflow channel 4 is on the discharge side of the circulation pump 3, and a solenoid valve 17 is interposed in the outflow channel 4 between the circulation pump 3 and the connection channel 12.

These solenoid valves 13 and 17, return water pump 15,
The circulation pump 3 and the liquid level controller 16 are automatically controlled by a control device 18. The control signal is transmitted to detectors 19 and 20 installed in the return waterway 5.
Receive from.

When the hot water reaches a high temperature close to the flushing temperature and the detected current value of the detector 20 exceeds the set threshold value, the control device 18 issues a control signal to stop the circulation pump 3 and close the electric valve 17. 13
Sends a control signal to open. As a result, the water in the collector 1 and the pipes enters the return water tank 7, but the return water pump 1 works in conjunction with the liquid level controller 16.
5, the water in the return water tank 7 is returned to the heat storage tank 2 while maintaining a predetermined water level. At this time, nitrogen gas is automatically introduced from the nitrogen gas introduction pipe 6 into the space inside the pipe line and the collector created by this water removal, and the water and nitrogen gas are replaced. Therefore, air is prevented from coming into contact with high-temperature parts within the system, effectively preventing corrosion due to oxygen, and heat is returned to the heat storage tank 2 via the water return tank 7 without escaping outside the system. Become.

Similarly, in the case of freezing, if the detector 19 detects a temperature close to the freezing temperature and this current value is outside the set range, the circulation pump 3 is stopped, the solenoid valve 17 is closed, and the solenoid valve 13 is closed. By opening the collector 1, water is drained from the collector 1, and the water is returned to the heat storage tank via the return tank 7. In this case as well, the inside of the system is replaced with nitrogen gas, and the heat retained within the system is stored in the heat storage tank 2.

To return to normal operation, reverse the operation and turn off collector 1.
The water in the heat storage tank 2 is fed into the system, and when the nitrogen gas in the system is compressed to a predetermined pressure or higher, it is discharged from the system through the automatic air bleed valve 11, creating a state in which virtually no oxygen enters the system. Operation continues under an inert atmosphere.

As described above, according to the present invention, flushing phenomenon and freezing can be prevented, air can be prevented from entering the system during draining, oxygen corrosion can be effectively prevented, and smooth operation can be achieved. The present invention provides a desirable solar heat collecting device that can minimize the progress of corrosion and can operate for a long period of time while avoiding abnormal situations throughout the year.

[Brief explanation of drawings]

FIG. 1 is an equipment layout system diagram showing an embodiment of the apparatus of the present invention. 1... Solar heat collector (collector), 2... Heat storage tank, 3... Circulation pump, 4... Outgoing channel, 5...
Return water channel, 6... Nitrogen gas introduction pipe, 7... Return water tank,
8...Low pressure nitrogen supply device, 13, 17... Solenoid valve, 15... Return water pump, 19, 20... Abnormal situation detector.

Claims (1)

[Claims] 1 In a solar system in which a circulation waterway is formed between a solar heat collector and a heat storage tank, a nitrogen gas introduction pipe is connected to the circulation road, and a water return tank is connected to the outgoing pipe line from the heat storage tank to the solar heat collector. At the same time, a pipe is installed to send water from the water return tank to the heat storage tank, and when or before an abnormal situation such as flushing or freezing occurs, the water in the solar heat collector is returned to the heat storage tank via the water return tank, and the system A solar heat collection device that replaces the space inside with nitrogen gas after draining water.