JPH0886517A - Heat supplying facility - Google Patents

Abstract

PURPOSE: To provide a heat supplying facility, capable of supplying stabilized cold heat without destroying a thermal stratification in the heat storage tank of cold water/hot-water even during rise-up operation upon starting a heat pump, improving the thermal efficiency of cool storage, operating the heat pump at the highest efficient point and contriving energy saving. CONSTITUTION: A heat supplying facility is provided with a heat pump 1 and a thermal stratification type cold water/hot-water heat storage tank 12 and is constituted so as to supply hot-water and cold water, produced by the heat pump 1, to the demanding end of heat through the heat storage tank 12. The heat supplying facility is provided with a control means, reducing the flow rate of water, sent to the heat pump 1, during rise-up operation upon starting the heat pump 1 compared with the flow rate upon full-load operation while increasing the flow rate gradually when the outlet temperature of the heat pump 1 has arrived at a set temperature or a predetermined period of time has elapsed from the starting of the heat pump.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a heat pump and a temperature stratified cold water / hot water heat storage tank, and supplies heat to the heat demand end through the cold water / hot water heat storage tank. It relates to a method of operating equipment. In the present specification, the heat pump means not only a narrow sense heat pump for cold temperature manufacturing but also a broad sense heat pump including a refrigerator.

[0002]

Conventionally, heat pumps and temperature stratified cold water /
In a heat supply facility having a hot water heat storage tank and configured to supply hot water and cold water made by a heat pump to the heat demand end through the cold water / hot water heat storage tank, the heat pump can be operated from the heat pump even during startup operation at the time of starting the heat pump. The flow rate of water sent to the cold water / hot water heat storage tank and from the cold water / hot water heat storage tank to the heat pump was a predetermined flow rate close to that at full load operation.

[0003]

However, when a predetermined flow rate close to full load operation is supplied to the cold / hot water heat storage tank even during the startup operation at the time of starting the heat pump as in the above-mentioned conventional case,
There was a problem that the water having a temperature outside the specified range that did not reach the set temperature at the time of starting the heat pump was returned to the cold water / hot water heat storage tank as it was, and the temperature stratification of the cold water / hot water heat storage tank was destroyed.

The present invention has been made in view of the above points, and eliminates the above-mentioned problems and enables stable supply of cold heat without destroying the temperature stratification of a cold water / hot water heat storage tank even during startup operation at the time of starting a heat pump. Enable heat storage efficiency and improve heat storage efficiency, and operate the heat pump at the highest efficiency point,
It is an object to provide a heat supply facility that can save energy.

[0005]

In order to solve the above problems, the present invention comprises a heat pump and a thermal stratification type cold water / hot water heat storage tank, and heats hot water and cold water produced by the heat pump through the heat storage tank. In the heat supply equipment configured to supply to the demand end, the flow rate of water sent to the heat pump during the startup operation at the time of starting the heat pump is made smaller than that at full load operation, and when the outlet temperature of the heat pump reaches the set temperature or It is characterized in that a control means for gradually increasing the flow rate is provided after a lapse of a predetermined time from the activation of the heat pump.

In addition, heat pump and temperature stratified cold water /
In a heat supply facility having a hot water heat storage tank and configured to supply hot water and cold water made by a heat pump to the heat demand end through the heat storage tank, the heat storage tank is provided in a return pipe returning from the heat pump outlet to the heat storage tank. From the heat pump to the heat pump, or a branch pipe leading to a heat storage tank at the same height as the suction port of the feed pipe is provided. Water of temperature outside the specified range until the outlet temperature reaches the set temperature or until a predetermined time elapses from the start of the heat pump is returned via the branch pipe to the feed pipe or the heat storage tank at the same height as the suction port of the feed pipe. When the outlet temperature of the heat pump reaches the set temperature or when a predetermined time has elapsed from the start of the heat pump, it is returned to the heat storage tank through the return pipe, and then the flow Characterized in that a gradually increasing control means.

Further, the suction port of the feed pipe and the discharge port of the branch pipe are located at the same height in the heat storage tank, and the suction port and the discharge port are located in the same cough. Characterize.

[0008]

According to the present invention, by adopting the above configuration, the control means reduces the flow rate of water sent to the heat pump during the startup operation at the time of starting the heat pump as compared with the full load operation, and the outlet temperature of the heat pump reaches the set temperature. After the start of the heat pump or when the outlet temperature reaches the predetermined temperature after the start of the heat pump, the flow rate is gradually increased, so that the influence of the water outside the specified range on the temperature stratification of the heat storage tank can be minimized. The thermal stratification of the heat storage tank is not destroyed even during the startup operation of.

Further, a feed pipe for feeding water from the heat storage tank to the heat pump or a branch pipe reaching the heat storage tank at the same height as the suction port of the feed pipe is provided in the return pipe returning from the heat pump outlet to the heat storage tank, and the control means is During start-up operation at the time of starting the heat pump, reduce the flow rate from that at full load operation, and branch water with a temperature outside the specified range until the outlet temperature of the heat pump reaches the set temperature or until a predetermined time elapses from the start of the heat pump. Return to the feed pipe or the heat storage tank at the same height as the suction port of the feed pipe through the pipe, and when the outlet temperature of the heat pump reaches the set temperature or a predetermined time has elapsed from the start of the heat pump, the outlet temperature becomes the predetermined temperature. Then, since it is returned to the heat storage tank through the return pipe, the temperature stratification of the heat storage tank is not destroyed even during the startup operation at the time of starting the heat pump, as in the above case.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of heat supply equipment of the present invention. As shown in FIG. 1, the heat supply equipment of the present invention includes a heat pump 1 and a heat storage tank 12, operates the heat pump 1 as a cold heat pump, and heats the cold water produced by the heat pump 1 through the heat storage tank 12. It is configured to supply to the demand end.

The heat pump 1 comprises a compressor 1-1, heat exchangers 1-2 and 1-3, valves 1-4 to 1-11 and the like. The heat storage tank 12 is a temperature stratification type heat storage tank, and includes a water layer having a water temperature of 14 ° C. and a cold water layer having a water temperature of 4 ° C. Heat storage tank 12
The heat pump 1 is connected via the feed pipe 7 and the pump 6, and is also connected via the return pipe 8 and the valve 11. The return pipe 8 and the suction port connection portion of the feed pipe 7 of the heat storage tank 12 are connected to each other via a branch pipe 9 and a valve 10. The heat source water 2 and the heat pump 1 are connected to the pump 3 via the pipe 4 and the pipe 5. Reference numeral 15 in the figure denotes a temperature sensor that detects the water temperature at the outlet of the heat pump 1.

In the heat supply equipment having the above-mentioned structure, when the heat pump 1 is operated as a cold heat pump, the valves 1-4 to 1-7 are closed and the valves 1-8 to 1-11 are opened. The water having a water temperature of 14 ° C. in the heat storage tank 12 is sent by the pump 6 through the sending pipe 7 to the inlet of the heat pump 1, and the heat is absorbed by the heat exchanger 1-3 to become cold water having a water temperature of 4 ° C. The water is sent from the outlet 1 through the return pipe 8 and the valve 11 to the layer of the heat storage tank 12 having a water temperature of 4 ° C.

The heat source water 2 sent from the pump 3 to the heat pump 1 through the pipe 4 is heated by the heat exchanger 1-2 and returned to the heat source water 2 through the pipe 5. Cold water having a water temperature of 4 ° C. in the heat storage tank 12 is supplied to the heat demand end through the pipe 13 by the pump 14.

As shown in FIG. 4, the heat pump 1 has a start-up start-up characteristic of about 15 minutes before it can be operated at full load.
The flow rate of water at 4 ° C. is made as small as possible compared to the flow rate corresponding to the full load when cooling from 14 ° C. to 4 ° C., and the amount of breaking the temperature stratification of the heat storage tank 12 is made small.

When water having a water temperature outside the specified range which does not reach the water temperature of 4 ° C. when the heat pump 1 is started is returned to the lower layer of the heat storage tank 12 at the water temperature of 4 ° C. through the return pipe 8, the temperature stratification there. Is broken and the water temperature of the pipe 13 sent to the heat demand end is outside the specified range. Moreover, it also leads to a reduction in heat storage efficiency.

Therefore, when the heat pump 1 is started up, the water having a temperature outside the specified range is returned to the layer having the water temperature of 14 ° C. in the heat storage tank 12 through the branch pipe 9 and the valve 10. In this case, the temperature stratification at the water temperature of 14 ° C. is destroyed, but there is little influence on the temperature stratification at the water temperature of 4 ° C. supplied to the heat demand end, and stable heat supply becomes possible. Furthermore, if the return port of the branch pipe 9 to the heat storage tank 12 is in the same position as the suction port connection portion of the feed pipe 7, the disturbance of the temperature stratification of the heat storage tank 12 can be minimized.

When the water temperature at the outlet 1-12 of the heat pump 1 reaches a set temperature (a temperature close to 4 ° C.), the valve 11 is opened and the valve 10 is closed, and cold water from the heat pump 1 is passed through the return pipe 8 to the heat storage tank. Return to layer of water temperature 12 at 4 ° C. At this point in time, the flow rate of the water supplied to the heat pump 1 has been considerably reduced, and the state is in the partial load operation. Therefore, the flow rate of the supply water is gradually increased to shift to the full load operation.

In the above embodiment, when the water temperature at the outlet 1-12 of the heat pump 1 reaches the set temperature, the cold water from the heat pump 1 is returned to the layer of the heat storage tank 12 having the water temperature of 14 ° C. through the return pipe 8. Configured, heat pump 1
After a lapse of a predetermined time (for example, a rising time of about 15 minutes as shown in FIG. 4), the cold water from the heat pump 1 may be returned to the layer of the heat storage tank 12 having the water temperature of 4 ° C. through the return pipe 8. .

The control of the heat supply equipment having the above construction is performed by a control means equipped with a computer (not shown). FIG. 2 is a diagram showing a control flow of this control means. First, the valve 10 is opened and the valve 11 is closed (step ST1). Subsequently, the pump 6 is operated (step ST2) to start water flow. The flow rate q at the start of water flow should be minimized. The pump 3 is operated to start passing the heat source water 2 (step ST
3).

Then, the operation of the heat pump 1 is started (step ST4). From the output of the temperature sensor 15, wait until the water temperature at the outlet reaches a specified temperature (a temperature close to 4 ° C.) (step ST5), and when it reaches the specified temperature, the valve 1
0 is closed and the valve 11 is opened to enter the normal operation mode (step ST6). Subsequently, the flow rate q is gradually increased (step ST7), and when the flow rate q reaches the predetermined flow rate (step ST8), the heat pump 1 is set to full load operation (step ST9), and the operation is continued until a heat pump stop command is issued (step ST9). ST10).

When a heat pump stop command is issued, the heat pump 1 is stopped (step ST11), and it is judged whether or not the water temperature at the outlet of the heat pump 1 is the specified temperature (step ST).
12) If the temperature is not the specified temperature, the valve 10 is opened, the valve 11 is closed (step ST13), the pump 6 is stopped (step ST14), and the pump 3 is stopped (step ST15).

FIG. 3 is a diagram showing the construction of heat supply equipment when the heat pump 1 is operated as a hot heat pump and hot water produced by the heat pump 1 is supplied to the heat demand end through the heat storage tank 12.

The valves 1-4 to 1-7 of the heat pump 1 are opened and the valves 1-8 to 1-11 are closed. The water having a water temperature of 28 ° C. in the heat storage tank 12 is sent by the pump 6 through the feed pipe 7 to the inflow port of the heat pump 1 and heated by the heat exchanger 1-3, and as the hot water having a water temperature of 60 ° C, the outflow port of the heat pump 1. The water is sent to the layer of the heat storage tank 12 having a water temperature of 60 ° C. from the return pipe 8 and the valve 11.

The heat of the heat source water 2 sent to the heat pump 1 through the pipe 4 by the pump 3 is absorbed by the heat exchanger 1-2 and returned to the heat source water 2 through the pipe 5. Heat storage tank 12
The hot water having a water temperature of 60 ° C. is supplied to the demand end by the pump 14 through the pipe 13.

Since the heat pump 1 has a startup characteristic of about 15 minutes before it can be operated at full load,
During this time, the flow rate of the warm water of 28 ° C. sent to the heat pump 1 is made as small as possible compared to the flow rate corresponding to the full load when the temperature is raised from 28 ° C. to 60 ° C., and the amount of breaking the temperature stratification of the heat storage tank 12 is reduced.

Water temperature at the time of starting the heat pump 1 60 ° C.
If water having a temperature outside the specified range that does not reach the temperature is returned to the upper layer of the heat storage tank 12 at a water temperature of 60 ° C through the return pipe 8 as it is, the temperature stratification there is broken, and the pipe 13 for sending to the heat demand end is The water temperature will be outside the specified range. Moreover, it also leads to a reduction in heat storage efficiency.

Therefore, when the heat pump 1 is started up, water having a temperature outside the specified range is returned to the layer of the heat storage tank 12 having a water temperature of 28 ° C. through the branch pipe 9 and the valve 10. In this case, the temperature stratification at a water temperature of 28 ° C is destroyed, but the water temperature supplied to the demand end is 6
A stable heat supply is possible with little influence on the temperature stratification at 0 ° C. Furthermore, if the return port of the branch pipe 9 to the heat storage tank 12 is in the same position as the suction port connection portion of the feed pipe 7, the disturbance of the temperature stratification of the heat storage tank 12 can be minimized.

When the water temperature at the outlet 1-12 of the heat pump 1 reaches the set temperature (a temperature close to 60 ° C.), the valve 11
Is opened, the valve 10 is closed, and hot water from the heat pump 1 is returned to the heat storage tank 12 at a water temperature of 60 ° C. through the return pipe 8. At this point in time, the flow rate of the water supplied to the heat pump 1 has been considerably reduced, and the state is in the partial load operation. Therefore, the flow rate of the supply water is gradually increased to shift to the full load operation.

In the above embodiment, when the water temperature at the outlet 1-12 of the heat pump 1 reaches the set temperature, the cold water from the heat pump 1 is returned to the layer of the heat storage tank 12 at the water temperature of 60 ° C. through the return pipe 8. Configured, heat pump 1
After a lapse of a predetermined time from, the cold water from the heat pump 1 may be returned to the layer of the heat storage tank 12 having the water temperature of 60 ° C. through the return pipe 8.

The above-mentioned control is performed by the control means equipped with a computer (not shown), which is the same as the case where the heat pump 1 is operated as a cold heat pump, and the explanation of the control flow is omitted.

In the above embodiment, the heat supply equipment provided with the heat pump 1 has been described as an example, but it is naturally possible to use a plurality of heat pumps 1.

[0032]

As described above, according to the present invention, the following excellent effects can be obtained. (1) The flow rate at the time of starting the heat pump is reduced as much as possible, and the flow rate is gradually increased when the outlet temperature of the heat pump reaches the set temperature or when a predetermined time has elapsed after the start of the heat pump. The effect on the temperature stratification of the heat storage tank due to the temperature outside the specified range that has not reached is minimized, and stable heat supply to the heat demand end becomes possible.

(2) Further, a return pipe returning from the heat pump outlet to the heat storage tank is provided with a feed pipe for feeding water from the heat storage tank to the heat pump or a branch pipe leading to the heat storage tank at the same height as the suction port of the feed pipe. Water with a temperature outside the specified range until the outlet temperature reaches the set temperature or until a predetermined time elapses from the start of the heat pump is returned to the feed pipe through the branch pipe or the heat storage tank at the same height as the suction port of the feed pipe. Therefore, the influence on the temperature stratification of the heat storage tank can be further minimized, and stable heat supply to the heat demand end can be achieved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of heat supply equipment for operating the heat pump of the present invention as a cold heat pump.

FIG. 2 is a diagram showing a control flow of the heat supply equipment of the present invention.

FIG. 3 is a diagram showing a configuration of heat supply equipment for operating the heat pump of the present invention as a heat pump.

FIG. 4 is a diagram showing a rising characteristic of a heat pump.

[Explanation of symbols]

 1 Heat Pump 2 Heat Source Water 3 Pump 4 Piping 5 Piping 6 Pump 7 Feeding Piping 8 Return Piping 9 Branch Pipe 10 Valve 11 Valve 12 Heat Storage Tank 13 Piping 14 Pump 15 Temperature Sensor

Claims (3)

[Claims] 1. A heat supply facility comprising a heat pump and a thermal stratification type cold water / hot water heat storage tank, and configured to supply hot water and cold water produced by the heat pump to a heat demand end through the heat storage tank. In the above, during the startup operation at the time of starting the heat pump, the flow rate of water to be sent to the heat pump is made smaller than that at the time of full load operation, and when the outlet temperature of the heat pump reaches a set temperature or when a predetermined time has elapsed from the start of the heat pump, the flow rate is set A heat supply facility characterized by being provided with control means for gradually increasing it. 2. A heat supply facility comprising a heat pump and a thermal stratification type cold water / hot water heat storage tank, and configured to supply hot water and cold water produced by the heat pump to the heat demand end through the heat storage tank. In the return pipe returning from the heat pump outlet to the heat storage tank, a feed pipe for sending water from the heat storage tank to the heat pump or a branch pipe reaching the heat storage tank at the same height as the suction port of the feed pipe is provided, and when the heat pump is started, During start-up operation, the flow rate is made smaller than that during full-load operation, and water having a temperature outside the specified range until the outlet temperature of the heat pump reaches a set temperature or a predetermined time elapses from the start of the heat pump through the branch pipe. To the feed pipe or the heat storage tank at the same height as the suction port of the feed pipe, and when the outlet temperature of the heat pump reaches a set temperature or the heat pump is turned on. Predetermined time so as to return to the heat storage tank through said return Ri pipe after the lapse, heat supply facilities, characterized in that a control means of increasing then the flow gradually from. 3. The suction port of the feed pipe and the discharge port of the branch pipe are located at the same height of the heat storage tank, and the suction port and the discharge port are located in the same cough. The heat supply equipment according to claim 2, wherein: