JP7599283B2 - High-temperature water supply equipment - Google Patents

Description

This disclosure relates to a high-temperature water supply system that supplies high-temperature water (including steam).

As an example of equipment that supplies steam, which is a form of high-temperature water, to a steam turbine, there is equipment described in the following Patent Document 1. This equipment includes a heat collector that collects sunlight to heat a heat medium, and a heat storage tank that stores the heat medium heated by the heat collector. One end of a water supply line and one end of a steam line are connected to the heat storage tank. The other end of this steam line is connected to the steam turbine. The water that flows through the water supply line is heated by heat exchange with the heat medium in the heat storage tank and becomes steam. This steam is supplied to the steam turbine via the steam line.

As described above, the equipment described in Patent Document 1 can effectively utilize solar energy, which is a type of renewable energy.

JP 2014-092086 A

As described above, the equipment described in Patent Document 1 can effectively utilize solar energy, which is a type of renewable energy.

In chemical, paper, steel and other factories that require large amounts of process steam as well as electricity, boilers, steam turbines and generators are installed in the factory to generate electricity and supply steam to the factory at the same time. This steam may be supplied directly to the factory process that uses steam after leaving the boiler without passing through the steam turbine. In other cases, this steam may be supplied to the steam turbine, and then extracted as extraction steam and exhaust from the steam turbine and supplied to the factory process. In either case, the amount of steam supplied to the factory process is adjusted according to the amount of steam required by the factory, which fluctuates from moment to moment. Since the steam extracted as process steam is not used to generate electricity, the amount of electricity that can be supplied to the factory also fluctuates from moment to moment. The electricity required by the factory also fluctuates. If the factory cannot supply the electricity required by the factory through its own power generation alone, it purchases the shortfall from an external power company, and conversely, if there is a surplus of electricity, it sells the surplus to an external party to adjust the supply and demand of electricity within the factory.

Recently, the installed capacity of renewable energy sources with variable output, such as solar and wind power, has been expanding. As a result, depending on the season, day of the week, time of day, etc., the amount of electricity generated by renewable energy sources can increase too much, and in order to ensure the stability of the grid, it may be necessary to reduce private generation.

Therefore, the purpose of this disclosure is to provide a high-temperature water supply system that can effectively utilize surplus energy.

In order to achieve the above object, a high-temperature water supply system according to one aspect of the present invention comprises:
The system includes a plurality of heat accumulators each having a heat accumulator, a heater for heating the heat accumulator for each of the plurality of heat accumulators, a high-temperature water line through which gaseous or liquid water flows, and a generator. The high-temperature water line passes through the plurality of heat accumulators so as to be in contact with the heat accumulator, and connects the plurality of heat accumulators in series. Among the plurality of heat accumulators, the heater of a first heat accumulator is a solar heater that uses solar light to heat the heat accumulator of the first heat accumulator. The heater of a second heat accumulator, which is disposed upstream of the first heat accumulator in the flow direction of water in the high-temperature water line, has an excess power heater that uses excess power of the power generated by the generator to heat the heat accumulator of the second heat accumulator. The heater of a third heat accumulator, which is disposed upstream of the second heat accumulator in the flow direction of water in the high-temperature water line, has an excess steam heater that uses steam or steam drain from a steam utilization facility to heat the heat accumulator of the third heat accumulator.

In this embodiment, the heat storage of the first heat storage device is heated by sunlight, which is a type of renewable energy. The heat storage of the upstream heat storage device is heated by excess steam, which is steam or steam drain from the steam utilization facility, or by excess electricity. However, the amount of energy generated fluctuates greatly for sunlight, which is a type of renewable energy, and excess steam and excess electricity, which are types of excess energy. For this reason, there are cases where the heat storage of the first heat storage device is not heated by sunlight, and cases where the heat storage of the upstream heat storage device is not heated by excess energy. Water flowing through the high-temperature water line can be heated by the heat storage of at least one of the multiple heat storage devices as it passes through the multiple heat storage devices. For this reason, in this embodiment, water with a higher temperature than the water flowing in from the upstream end of the high-temperature water line can be supplied to the high-temperature water utilization facility.

In addition, in this embodiment, the energy described above is stored in the heat storage device and used to heat the water, so fluctuations in the amount of heating of the water can be mitigated in response to fluctuations in the amount of energy generated. Furthermore, even if one of these energies cannot be used, if the other energy is available, the water can be heated with the other energy. Therefore, in the high-temperature water supply system of this embodiment, heated water can be supplied to the high-temperature water utilization system for a long period of time even when energy with large fluctuations in the amount of generation is used. In other words, in the high-temperature water supply system of this embodiment, the energy of sunlight R and surplus energy, which have large fluctuations in the amount of generation, can be effectively utilized.

According to one aspect of the present disclosure, surplus energy can be effectively utilized to supply high-temperature water.

1 is an overall system diagram of a high-temperature water supply facility according to an embodiment of the present disclosure; FIG. 11 is a cross-sectional view of a first heat storage unit in a first modified example according to the present disclosure. FIG. 11 is a cross-sectional view of a first heat storage unit in a second modified example according to the present disclosure. FIG. 11 is an overall system diagram of a high-temperature water supply facility in a modified example of an embodiment according to the present disclosure.

Below, one embodiment of the high-temperature water supply system according to the present disclosure and various modified examples thereof will be described in detail with reference to the drawings.

"Embodiment"
An embodiment of a high-temperature water supply facility according to the present disclosure will be described with reference to Fig. 1. The high-temperature water supply facility of this embodiment is a facility that supplies steam to a steam utilization facility (high-temperature water utilization facility) that utilizes steam, which is high-temperature water. Note that, hereinafter, when simply referred to as water, this includes liquid water and steam, which is gaseous water.

The high-temperature water supply system of this embodiment includes a steam power generation system 10, a plurality of heat storage units 21, 22, and 23 each having a heat storage body 24, a heater 30 for heating the heat storage body 24 for each of the plurality of heat storage units 21, 22, and 23, a high-temperature water line 50 through which gaseous or liquid water flows, and a control device 60.

The steam power generation facility 10 includes a boiler 11 that generates steam, a steam turbine 12 that is driven by the steam, a generator 15 that generates electricity by driving the steam turbine 12, a condenser 13 that converts the steam exhausted from the steam turbine 12 back into liquid water, and a pump 14 that sends the liquid water in the condenser 13 to the boiler 11.

The generator 15 is connected to a main power path 16. This main power path 16 is connected to an external system 18 and an on-site system 19.

One end of the high-temperature water line 50 is connected to the steam turbine 12 so that extracted steam (or exhaust steam; the same applies below) from the steam turbine 12 can be introduced into the high-temperature water line 50. The other end of the high-temperature water line 50 is connected to a steam utilization facility (high-temperature water utilization facility) 70. In the following, the upstream side of the high-temperature water line 50 in the direction of water flow, in other words, the side of one end relative to the other end, will be referred to simply as the upstream side Du. In the following, the downstream side of the high-temperature water line 50 in the direction of water flow, in other words, the side of the other end relative to the one end, will be referred to simply as the downstream side Dd.

One end of a steam drain recovery line 55 is connected to the steam utilization equipment 70. The other end of this steam drain recovery line 55 is connected to the condenser 13. The steam supplied to the steam utilization equipment 70 becomes steam drain, i.e., liquid water, within the steam utilization equipment 70. This steam drain flows into the condenser 13 via the steam drain recovery line 55.

The high-temperature water line 50 passes through the heat storage units 21, 22, and 23 and is in contact with the heat storage unit 24. That is, the portion of the high-temperature water line 50 that passes through the heat storage units 21, 22, and 23 functions as a heat transfer tube that exchanges heat between the water passing through the high-temperature water line 50 and the heat storage unit 24. This high-temperature water line 50 connects the heat storage units 21, 22, and 23 in series. In this embodiment, the heat storage units 21, 22, and 23 include three heat storage units: the first heat storage unit 21, the second heat storage unit 22, and the third heat storage unit 23. Of the three heat storage units 21, 22, and 23, the first heat storage unit 21 is located on the most downstream side Dd. Therefore, the second heat storage unit 22 and the third heat storage unit 23 are the upstream heat storage units 22 and 23 that are located upstream Du of the first heat storage unit 21. The third heat storage device 23 is disposed upstream Du of the second heat storage device 22.

The high-temperature water line 50 may be branched into multiple lines downstream Dd of the first heat accumulator 21. For example, when the high-temperature water line 50 is branched into two lines, one line forms a high-heated water line 51 and the other line forms a low-heated water line 52. The high-heated water line 51 is connected to a high-heated water utilization section 71 that utilizes high-heated water (high-temperature steam) in the steam utilization equipment 70. The low-heated water line 52 is connected to a low-heated water utilization section 72 that utilizes low-heated water (low-temperature steam) in the steam utilization equipment 70. Each of the high-heated water line 51 and the low-heated water line 52 is provided with a device or the like that reduces the temperature of the water flowing through these lines 51, 52 to the temperature required by the heated water utilization sections 71, 72.

Each of the heat storage devices 21, 22, and 23 has a heat storage body 24, a case 26 that covers the heat storage body 24, and a dispersion plate 26d. The dispersion plate 26d is a plate that divides the inside of the case 26 into a fluidized bed chamber 26f and a gas chamber 26g. In this embodiment, the heat storage body 24 is a plurality of heat storage material particles. The heat storage material particles are made of silica sand. The fluidized bed chamber 26f is the upper chamber based on the dispersion plate 26d. A plurality of heat storage material particles are arranged in this fluidized bed chamber 26f. A plurality of holes are formed in the dispersion plate 26d, which penetrate from the gas chamber 26g to the fluidized bed chamber 26f. In the case 26, a gas inlet 26i that introduces gas into the gas chamber 26g is formed in the part below the dispersion plate 26d. The gas that flows into the gas chamber 26g from the gas inlet 26i flows through the multiple holes in the dispersion plate 26d into the fluidized bed chamber 26f, fluidizing the multiple heat storage material particles in the fluidized bed chamber 26f. That is, the gas turns the multiple heat storage material particles in the fluidized bed chamber 26f into a fluidized bed 25. In the case 26, a gas exhaust port 26o for exhausting the gas is formed at the top of the fluidized bed chamber 26f. A portion of the high-temperature water line 50 that functions as a heat transfer tube is disposed in the fluidized bed 25.

In the above, the inside of the case 26 is divided by the dispersion plate 26d. However, the inside of the case 26 does not have to be divided by the dispersion plate 26d. In this case, a tube with multiple holes formed therein may be provided inside the case 26, and this tube may be connected to the gas inlet 26i so that air is blown into the case from the multiple holes of the tube. The inside of this tube functions as a gas chamber.

The case 26a of the first heat storage device 21 is provided with a thermometer 69 that detects the temperature of the fluidized bed 25. The case 26a has a top plate 26t. The top plate 26t has a top plate body 26tb and a window 26tw. The top plate body 26tb has an opening. The window 26tw is formed of a light-transmitting material and closes the opening. An example of a light-transmitting material is quartz glass.

The heater 30 of the first heat storage device 21 has a solar heater 31 that uses solar light R to heat the heat storage material particles of the first heat storage device 21. This solar heater 31 is a solar guide device that guides solar light R to the first heat storage device 21. The solar guide device has one or more heliostats 32 that guide solar light R to a target position, and a fixed reflector 35 that is arranged at the target position. The heliostat 32 has a reflector 33 that reflects solar light R, and a reflector driver 34 that changes the orientation of the reflector 33. The reflector driver 34 is a device that changes the orientation of the reflector 33 in accordance with the diurnal motion of the sun to guide the solar light R to the target position. The fixed reflector 35 guides the solar light R from all the heliostats 32 to the first heat storage device 21. The solar light R from the fixed reflector 35 is irradiated to the fluidized bed 25 through the window 26tw of the first heat storage device 21.

The heater 30 of the second heat storage device 22 has a surplus power heater 41 that uses surplus power generated by the generator 15 to heat the heat storage material particles of the second heat storage device 22. The surplus power heater 41 has an electric heater 42 that heats the heat storage material particles with surplus power, and a heat pump 43 that operates with the surplus power. The electric heater 42 has an electric heater main body 42a that is a heating body, and a heater drive circuit 42b that supplies power to the electric heater main body 42a. The heat pump 43 has an evaporator 44 that evaporates a liquid medium to make it a gas medium, a compressor 45 that compresses the gas medium, a condenser 46 that condenses the gas medium compressed by the compressor 45 to make it a liquid medium, an expander 47 that expands the liquid medium, and a drive 48 that drives the expander 47 and the compressor 45. The evaporator 44 is, for example, a heat exchanger that exchanges heat between the outside air and the liquid medium to cool the outside air while heating and evaporating the liquid medium. The condenser 46 is, for example, a heat exchanger that exchanges heat between the gaseous medium and the heat storage material particles to cool and condense the gaseous medium while heating the heat storage material particles. The expander 47 is, for example, a turbine or an expansion valve. The driver 48 has a motor 48a and a motor drive circuit 48b that supplies power to the motor 48a. The electric heater body 42a and the condenser 46 are arranged in the fluidized bed chamber 26f of the second heat accumulator 22.

The heater 30 of the third heat storage device 23 has a surplus power heater 41 that uses surplus power to heat the heat storage material particles of the third heat storage device 23, and a surplus steam heater 49 that uses steam or steam drain from the steam utilization equipment 70 to heat the heat storage material particles of the third heat storage device 23. The surplus power heater 41 has an electric heater 42 that heats the heat storage material particles with surplus power. The electric heater 42 has an electric heater main body 42a that is a heating body, and a heater drive circuit 42b that supplies power to the electric heater 42. The surplus steam heater 49 is a heat exchanger that exchanges heat between the steam or steam drain (hereinafter referred to as surplus steam) from the steam utilization equipment 70 and the heat storage material particles to heat the heat storage material particles. The electric heater 42 and the surplus steam heater 49 are arranged in the fluidized bed chamber 26f of the third heat storage device 23. The surplus steam heater 49 has an inlet and an outlet. The inlet is connected to an excess steam line 56 extending from the steam utilization equipment 70. The outlet is connected to an excess steam recovery line 57 extending from the condenser 13. Excess steam that is left over or no longer needed in the steam utilization equipment 70 flows into the surplus steam heater 49 from the steam utilization equipment 70 via the excess steam line 56. The temperature of this excess steam is higher than the temperature of the extracted steam from the steam turbine 12. The excess steam flowing out of the surplus steam heater 49 flows into the condenser 13 via the excess steam recovery line 57.

The heater drive circuit 42b and the motor drive circuit 48b of the surplus power heater 41 described above are both connected to the in-house system 19.

The control device 60 has a heating controller 61. The heating controller 61 gives various instructions to the heater drive circuit 42b and motor drive circuit 48b of the surplus power heater 41, and further to the reflector drive mechanism 34 of the solar heater 31. The heating controller 61 judges whether the generator 15 can generate surplus power. The heating controller 61 judges whether there is surplus power from the difference between the power generated by the generator 15 and the power required by the on-site system 19. When the heating controller 61 judges that the generator 15 can generate surplus power, it instructs the heater drive circuit 42b of the surplus power heater 41 to supply power to the electric heater main body 42a, and instructs the motor drive circuit 48b of the surplus power heater 41 to supply power to the motor 48a.

Next, we will explain the operation of the high-temperature water supply equipment described above.

When the boiler 11 of the steam power generation equipment 10 generates steam, this steam is supplied to the steam turbine 12, which drives the steam turbine 12. The generator 15 generates electricity by driving this steam turbine 12. The steam exhausted from the steam turbine 12 is returned to liquid water by the condenser 13. The liquid water in the condenser 13 is sent to the boiler 11 by the pump 14. A portion of the steam supplied to the steam turbine 12 is extracted as extracted steam and sent to the third heat accumulator 23 via the high-temperature water line 50.

Next, the operation of the high-temperature water supply facility when any one of the following conditions 1 to 5 is satisfied will be described.
Condition 1: The steam utilization equipment 70 generates excess steam having a higher temperature than the extracted steam, the generator 15 is capable of generating excess electricity, and the temperature of the fluidized bed 25 in the first heat accumulator 21 is equal to or higher than a predetermined temperature.
Condition 2: The steam utilization equipment 70 generates excess steam having a higher temperature than the extracted steam, the generator 15 is not capable of generating excess electricity, and the temperature of the fluidized bed 25 in the first heat accumulator 21 is equal to or higher than a predetermined temperature.
Condition 3: The steam utilization equipment 70 generates excess steam having a higher temperature than the extracted steam, the generator 15 is capable of generating excess electricity, and the temperature of the fluidized bed 25 in the first heat accumulator 21 is lower than a predetermined temperature.
Condition 4: The steam utilization equipment 70 does not generate excess steam having a temperature higher than that of the extracted steam, the generator 15 is capable of generating excess electricity, and the temperature of the fluidized bed 25 in the first heat accumulator 21 is equal to or higher than a predetermined temperature.
Condition 5: The steam utilization equipment 70 does not generate excess steam having a temperature higher than the extracted steam, the generator 15 is not capable of generating excess electricity, and the temperature of the fluidized bed 25 in the first heat accumulator 21 is equal to or higher than a predetermined temperature.

Even if sunlight R has reached the heliostat 32 and the fluidized bed 25 has been heated by the sunlight R, the temperature of the fluidized bed 25 in the first heat accumulator 21 may be below a predetermined temperature immediately after the heating of the fluidized bed 25 by the sunlight R begins. Conversely, even if sunlight R has not reached the heliostat 32 and the fluidized bed 25 has not been heated by the sunlight R, the temperature of the fluidized bed 25 in the first heat accumulator 21 may be equal to or higher than a predetermined temperature immediately after the heating of the fluidized bed 25 by the sunlight R ends.

First, the operation of the high-temperature water supply equipment when condition 1 is satisfied will be described. In this case, the multiple heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are heated by the excess steam flowing in the excess steam heater 49 and the electric heater 42 of the excess power heater 41. Therefore, a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the third heat accumulator 23 exchanges heat between the multiple heat storage material particles forming the fluidized bed 25 and the extracted steam flowing through this part of the high-temperature water line 50, heating this extracted steam. The steam heated in the third heat accumulator 23 flows into a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat accumulator 22.

When condition 1 is satisfied, the heat storage material particles forming the fluidized bed 25 of the second heat storage device 22 are heated by the electric heater 42 of the surplus power heater 41 and the condenser 46 of the heat pump 43. Therefore, a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat storage device 22 exchanges heat between the heat storage material particles forming the fluidized bed 25 and the steam flowing through this part of the high-temperature water line 50, heating this steam. The steam heated in the second heat storage device 22 flows into a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26a of the first heat storage device 21.

When condition 1 is satisfied, a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26a of the first heat accumulator 21 exchanges heat between the heat storage material particles forming the fluidized bed 25 and the steam flowing through the part of the high-temperature water line 50, heating the steam. The heated water, which is the steam heated in the first heat accumulator 21, flows into the steam utilization equipment 70 after being adjusted to an appropriate temperature. This steam (heated water) is used in the steam utilization equipment 70 and becomes steam with a reduced temperature or steam drain. A part of the steam or steam drain flows into the surplus steam heater 49 of the third heat accumulator 23 as surplus steam through the surplus steam line 56. Then, this surplus steam flows into the condenser 13 through the surplus steam recovery line 57. The remainder of the steam or steam drain flows into the condenser 13 through the steam drain recovery line 55.

Next, the operation of the high-temperature water supply equipment when condition 2 is satisfied will be described. In this case, the plurality of heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are heated by the surplus steam flowing in the surplus steam heater 49. However, when condition 2 is satisfied, since there is no surplus power, the plurality of heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are not heated by the electric heater 42 of the surplus power heater 41. A part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the third heat accumulator 23 exchanges heat between the plurality of heat storage material particles forming the fluidized bed 25 and the extracted steam flowing through this part of the high-temperature water line 50, and heats this extracted steam. The steam heated in the third heat accumulator 23 flows into a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat accumulator 22.

When condition 2 is met, as described above, since there is no surplus power, the plurality of heat storage material particles forming the fluidized bed 25 of the second heat accumulator 22 are not heated by the electric heater 42 of the surplus power heater 41 and the condenser 46 of the heat pump 43. Therefore, the part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat accumulator 22 hardly heats the steam even when heat is exchanged between the plurality of heat storage material particles forming the fluidized bed 25 and the steam flowing through this part of the high-temperature water line 50. The steam that is hardly heated in the second heat accumulator 22 flows into the part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26a of the first heat accumulator 21.

When condition 2 is met, a portion of the high-temperature water line 50 that functions as a heat transfer tube within the case 26a of the first heat storage device 21 exchanges heat between the multiple heat storage material particles that form the fluidized bed 25 and the steam flowing through this portion of the high-temperature water line 50, heating the steam. Thereafter, the heated water, which is the steam heated in the first heat storage device 21, flows in the same manner as in the first condition.

Next, the operation of the high-temperature water supply equipment when condition 3 is satisfied will be described. In this case, the multiple heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are heated by the excess steam flowing in the excess steam heater 49 and the electric heater 42 of the excess power heater 41. Therefore, a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the third heat accumulator 23 exchanges heat between the multiple heat storage material particles forming the fluidized bed 25 and the extracted steam flowing through this part of the high-temperature water line 50, heating this extracted steam. The steam heated in the third heat accumulator 23 flows into a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat accumulator 22.

When condition 3 is satisfied, the heat storage material particles forming the fluidized bed 25 of the second heat storage device 22 are heated by the electric heater 42 of the surplus power heater 41 and the condenser 46 of the heat pump 43. Therefore, a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat storage device 22 exchanges heat between the heat storage material particles forming the fluidized bed 25 and the steam flowing through this part of the high-temperature water line 50, heating this steam. The steam heated in the second heat storage device 22 flows into a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26a of the first heat storage device 21.

When condition 3 is met, the part of the high-temperature water line 50 that functions as a heat transfer tube in the case 26a of the first heat storage device 21 hardly heats the steam even when heat exchange is performed between the multiple heat storage material particles that form the fluidized bed 25 and the steam flowing through this part of the high-temperature water line 50. This steam flows in the same manner as in the first condition.

Next, the operation of the high-temperature water supply equipment when condition 4 is satisfied will be described. In this case, the heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are heated by the electric heater 42 of the surplus power heater 41. However, since there is no surplus steam, the heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are not heated by the surplus steam heater 49. A part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the third heat accumulator 23 exchanges heat between the heat storage material particles forming the fluidized bed 25 and the extracted steam flowing through this part of the high-temperature water line 50, and heats this extracted steam. The steam heated in the third heat accumulator 23 flows into a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat accumulator 22.

When condition 4 is satisfied, the heat storage material particles forming the fluidized bed 25 of the second heat storage device 22 are heated by the electric heater 42 of the surplus power heater 41 and the condenser 46 of the heat pump 43. Therefore, a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat storage device 22 exchanges heat between the heat storage material particles forming the fluidized bed 25 and the steam flowing through this part of the high-temperature water line 50, heating this steam. The steam heated in the second heat storage device 22 flows into a part of the high-temperature water line 50 functioning as a heat transfer tube in the case 26a of the first heat storage device 21.

When condition 4 is satisfied, a portion of the high-temperature water line 50 that functions as a heat transfer tube in the case 26a of the first heat storage device 21 exchanges heat between the multiple heat storage material particles that form the fluidized bed 25 and the steam flowing through this portion of the high-temperature water line 50, heating the steam. This steam flows in the same manner as in the first condition.

Next, the operation of the high-temperature water supply equipment when condition 5 is satisfied will be described. In this case, since there is no surplus steam, the plurality of heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are not heated by the surplus steam heater 49. Also, since there is no surplus power in this case, the plurality of heat storage material particles forming the fluidized bed 25 of the third heat accumulator 23 are not heated by the electric heater 42 of the surplus power heater 41. Therefore, even if the plurality of heat storage material particles forming the fluidized bed 25 and the extracted steam flowing through this part of the high-temperature water line 50, which functions as a heat transfer tube in the case 26 of the third heat accumulator 23, are heat exchanged, this extracted steam hardly heats this extracted steam. The steam that is hardly heated in the third heat accumulator 23 flows into the part of the high-temperature water line 50 which functions as a heat transfer tube in the case 26 of the second heat accumulator 22.

When condition 5 is satisfied, as described above, since there is no surplus power, the plurality of heat storage material particles forming the fluidized bed 25 of the second heat storage device 22 are not heated by the electric heater 42 of the surplus power heater 41 and the condenser 46 of the heat pump 43. Therefore, even if the heat storage material particles forming the fluidized bed 25 are heat exchanged with the steam flowing through the portion of the high-temperature water line 50, the portion of the high-temperature water line 50 functioning as a heat transfer tube in the case 26 of the second heat storage device 22 hardly heats the steam. The steam that is not heated in the second heat storage device 22 flows into the portion of the high-temperature water line 50 functioning as a heat transfer tube in the case 26a of the first heat storage device 21.

When condition 5 is met, a portion of the high-temperature water line 50 functioning as a heat transfer tube within the case 26a of the first heat accumulator 21 exchanges heat between the heat storage material particles forming the fluidized bed 25 and the steam flowing through this portion of the high-temperature water line 50, heating the steam. This steam flows in the same manner as in the first condition. Note that the temperature of the steam flowing out from the first heat accumulator 21 to the high-temperature water line differs under each of conditions 1 to 5, and therefore the amount of heat loss as the steam flows into the steam utilization facility 70 also differs under each of conditions 1 to 5.

As described above, in the high-temperature water supply system of this embodiment, extracted steam heated in at least one of the multiple heat accumulators 21, 22, and 23, i.e., extracted steam having a higher temperature than the extracted steam immediately after flowing out of the steam turbine 12, can be supplied to the steam utilization system (high-temperature water utilization system) 70.

The energy of sunlight R is a type of renewable energy. Moreover, surplus steam or surplus electricity is a type of surplus energy. The energy of sunlight R and surplus energy both fluctuate greatly in the amount of energy generated. In this embodiment, these energies are stored in the heat storage devices 21, 22, and 23 and used to heat the extracted steam, so that the fluctuation in the amount of heat of the extracted steam can be mitigated in response to the fluctuation in the amount of generation of these energies. Furthermore, even if one of these energies cannot be used, if the other energy is available, the extracted steam can be heated with the other energy. Therefore, in the high-temperature water supply system of this embodiment, even if an energy whose generation amount fluctuates greatly is used, heated extracted steam can be supplied to the steam utilization system 70 for a long period of time. In other words, in the high-temperature water supply system of this embodiment, the energy of sunlight R and surplus energy whose generation amount fluctuates greatly can be effectively utilized.

The heat storage body 24 of the first heat storage device 21 may or may not be heated by sunlight R, which is a type of renewable energy. The heat storage body 24 of the second heat storage device 22 and the heat storage body 24 of the third heat storage device 23 may or may not be heated by surplus steam or surplus electricity. Therefore, the temperature of the water that has passed through all of the heat storage devices 21, 22, and 23 changes depending on these cases. In this embodiment, by adjusting the temperature of the water that has passed through all of the heat storage devices 21, 22, and 23 depending on the supply destination, the heated water can be effectively used at the supply destination.

"Variations"
The first heat storage device 21A of the first modification will be described with reference to FIG. 2. The first heat storage device 21A of this modification has a heat storage body 24, a case 26A, and a dispersion plate 26d, similar to the first heat storage device 21 in the above embodiment. However, the case 26A of the first heat storage device 21A of this modification is different from the case 26a of the first heat storage device 21 in the above embodiment. The case 26A of the first heat storage device 21A of this modification has a top plate 26tA having an opening and a lid 28 that closes the opening. The lid 28 is provided so that the opening can be opened and closed. In this modification, when sunlight R reaches the heliostat 32, the lid 28 is in an open state. On the other hand, when sunlight R does not reach the heliostat 32, the lid 28 is in a closed state, suppressing heat dissipation from the heat storage body 24 in the case 26.

The first heat storage device 21B of the second modified example will be described with reference to FIG. 3. The first heat storage device 21B of this modified example has a heat storage body 24, a case 26B, and a dispersion plate 26d, similar to the first heat storage device 21 in the above-mentioned embodiment. However, the case 26B of the first heat storage device 21B of this modified example is different from the case 26a of the first heat storage device 21 in the above-mentioned embodiment. The case 26B of the first heat storage device 21B of this modified example has a top plate 26tB having an opening, and a light receiving portion 29 that closes this opening. The light receiving portion has a conical portion 29a whose inner diameter gradually decreases as it goes downward, and a cylindrical portion 29b connected to the lower end of the conical portion 29a. The upper and lower ends of the conical portion 29a are open. The upper end of the cylindrical portion 29b is open and connected to the lower end opening of the conical portion 29a. The lower end of the cylindrical portion 29b is closed. The cylindrical portion 29b is disposed within the fluidized bed 25. Sunlight R enters the light-receiving portion 29 from the upper end opening of the conical portion 29a. A portion of the sunlight R that enters the light-receiving portion 29 reaches the inner surface of the cylindrical portion 29b and heats the cylindrical portion 29b. Another portion of the sunlight R that enters the light-receiving portion 29 is reflected by the inner surface of the conical portion 29a and then reaches the inner surface of the cylindrical portion 29b and heats the cylindrical portion 29b. The cylindrical portion 29b heated by the sunlight R heats the multiple heat storage material particles that form the fluidized bed 25.

The heat storage material particles in the above embodiment are silica sand. However, the heat storage material particles do not have to be silica sand. For example, the heat storage material particles may be made of iron oxide or silicon carbide. The heat storage material particles may also be a mixture of two or more of silica sand, iron oxide, and silicon carbide. The heat storage body does not have to be a plurality of heat storage material particles. Specifically, the heat storage body 24 may be, for example, sodium nitrate, sodium nitrite, potassium nitrate, or a molten salt that is a mixture of these.

When a plurality of heat storage particles made of at least one of silica sand, iron oxide, and silicon carbide are used as the heat storage body, the purchase cost of the heat storage body can be reduced compared to when molten salt is used as the heat storage body. Furthermore, in this case, the heat storage body is easy to handle, and there is no need to strictly control the leakage of the heat storage body from the case 26. Therefore, as in the above-mentioned embodiment, when a plurality of heat storage particles made of at least one of silica sand, iron oxide, and silicon carbide are used as the heat storage body, the manufacturing cost of the high-temperature water supply equipment can be reduced.

In the above embodiment, the high-temperature water line 50 branches into two lines downstream Dd of the first heat accumulator 21. However, this high-temperature water line 50 does not have to branch.

The heater 30 of the second heat storage device 22 in the above embodiment has two types of surplus power heaters 41, an electric heater 42 and a heat pump 43. However, the heater 30 of the second heat storage device 22 may be one type of surplus power heater 41, an electric heater 42 or a heat pump 43. The surplus power heater 41 of the third heat storage device 23 is an electric heater 42, but may be a heat pump 43. In addition, the heater 30 of the third heat storage device 23 has a surplus power heater 41 and a surplus steam heater 49, but may be only a surplus steam heater 49.

In the above embodiment, the number of heat accumulators in the high-temperature water supply facility is three. However, the number of heat accumulators in the high-temperature water supply facility may be two. In this case, of the two heat accumulators, the heater for the first heat accumulator is the solar heater 31, and the heater for the second heat accumulator is at least one of the surplus power heater 41 and the surplus steam heater 49. The number of heat accumulators in the high-temperature water supply facility may be four or more.

The high-temperature water supply equipment in the above embodiment heats the extracted steam extracted from the steam turbine 12 constituting a part of the steam power generation equipment 10. However, the high-temperature water supply equipment may heat steam or steam drain from the steam utilization equipment 70 as shown in FIG. 4. In this case, one end of the high-temperature water line 50 is connected to the steam utilization equipment 70. In this high-temperature water line 50, the line between the steam utilization equipment 70 and the third heat accumulator 23 is also a steam drain recovery line 55 through which the steam drain from the steam utilization equipment 70 flows. In this case, a condenser 58 and a feed water pump 59 are provided in the steam drain recovery line 55, so that the steam drain is condensed and then sent to the third heat accumulator 23. In addition, the excess steam recovery line 57 extending from the excess steam heater 49 is connected to this steam drain recovery line 55. Therefore, in the high-temperature water supply system shown in FIG. 4, the water circulating in the steam utilization system 70 and the multiple heat accumulators 21, 22, and 23 is independent of the water circulating in the steam power generation system 10.

"Additional Notes"
The high-temperature water supply facility in the above embodiment can be understood, for example, as follows.
(1) The high-temperature water supply equipment in the first aspect includes:
The system includes a plurality of heat accumulators 21, 22, 23 each having a heat storage body 24, a heater 30 for heating the heat storage body 24, a high-temperature water line 50 through which gaseous or liquid water flows, and a generator 15 for each of the plurality of heat accumulators 21, 22, 23. The high-temperature water line 50 passes through the plurality of heat accumulators 21, 22, 23 so as to be in contact with the heat storage body 24, and connects the plurality of heat accumulators 21, 22, 23 in series. Of the plurality of heat accumulators 21, 22, 23, the heater 30 of the first heat accumulator 21 is a solar heater 31 that utilizes solar light R to heat the heat storage body 24 of the first heat accumulator 21. The heater 30 of the upstream heat accumulators 22, 23, which are located upstream Du of the first heat accumulator 21 in the flow direction of water in the high-temperature water line 50, has at least one of the heaters 41, 49: a surplus power heater 41 that uses surplus power generated by the generator 15 to heat the heat accumulator 24 of the upstream heat accumulators 22, 23, and a surplus steam heater 49 that uses steam or steam drain from a steam utilization equipment to heat the heat accumulator 24 of the upstream heat accumulators 22, 23.

In this embodiment, the heat storage body 24 of the first heat storage device 21 is heated by sunlight R, which is a type of renewable energy. The heat storage body 24 of the upstream heat storage devices 22 and 23 is heated by excess steam, which is steam or steam drain from the steam utilization facility, or by excess electricity. However, the amount of energy generated varies greatly for sunlight R, which is a type of renewable energy, and excess steam and excess electricity, which are types of excess energy. For this reason, there are cases where the heat storage body 24 of the first heat storage device 21 is not heated by sunlight R, and cases where the heat storage body 24 of the upstream heat storage devices 22 and 23 is not heated by excess energy. The water flowing through the high-temperature water line 50 can be heated by the heat storage body 24 of at least one of the multiple heat storage devices 21, 22, and 23 during the process of passing through the multiple heat storage devices 21, 22, and 23. For this reason, in this embodiment, water with a higher temperature than the water flowing in from the upstream end of the high-temperature water line 50 can be supplied to the high-temperature water utilization facility.

In addition, in this embodiment, the energy described above is stored in the heat storage devices 21, 22, and 23 and used to heat water, so that fluctuations in the amount of water heated can be mitigated in response to fluctuations in the amount of energy generated. Furthermore, even if one of these energies cannot be used, if the other energy is available, the water can be heated with this other energy. Therefore, in the high-temperature water supply system of this embodiment, heated water can be supplied to the high-temperature water utilization system for a long period of time even when energy whose generation amount fluctuates greatly is used. In other words, in the high-temperature water supply system of this embodiment, the energy of sunlight R and surplus energy, whose generation amount fluctuates greatly, can be effectively utilized.

(2) The high-temperature water supply equipment in the second method is as follows:
In the high-temperature water supply facility of the first aspect, the heater 30 of the upstream heat accumulators 22, 23 has the surplus power heater 41. The facility further includes a heating controller 61 that determines whether the generator 15 can generate surplus power and drives the surplus power heater 41 with the surplus power when the generator 15 can generate the surplus power.

(3) The high-temperature water supply equipment in the third aspect includes:
In the high-temperature water supply facility of the second embodiment, the surplus power heater 41 has at least one of an electric heater 42 that heats the heat storage body 24 with the surplus power and a heat pump 43 that operates with the surplus power. The heat pump 43 has an evaporator 44 that evaporates a liquid medium to make a gaseous medium, a compressor 45 that compresses the gaseous medium, a condenser 46 that condenses the gaseous medium compressed by the compressor 45 to make a liquid medium, an expander 47 that expands the liquid medium, and a driver 48 that is driven by the surplus power to operate the compressor 45. The condenser 46 is a heat exchanger that exchanges heat between the gaseous medium and the heat storage body 24 of the upstream heat storage devices 22 and 23 to cool the gaseous medium while heating the heat storage body 24.

(4) The high-temperature water supply equipment in the fourth aspect includes:
In the high-temperature water supply facility according to any one of the first to third aspects, the upstream heat accumulators 22, 23 include a second heat accumulator 22 and a third heat accumulator 23 disposed on the upstream side Du of the second heat accumulator 22. The heater 30 of the second heat accumulator 22 includes at least the surplus power heater 41. The heater 30 of the third heat accumulator 23 includes at least the surplus steam heater 49.

In this embodiment, the surplus energy that heats the heat storage body 24 of the second heat storage device 22 is different from the surplus energy that heats the heat storage body 24 of the third heat storage device 23. Therefore, in this embodiment, even if one of these surplus energies cannot be used, if the other surplus energy is available, water can be heated with the other surplus energy.

(5) The high-temperature water supply equipment in the fifth aspect includes:
In the high-temperature water supply equipment of any of the first to fourth aspects, the solar heater 31 is a solar guide device having one or more heliostats 32 that guide solar light R to a target position, and a reflector that is arranged at the target position and guides the solar light R from the one or more heliostats 32 to the first heat storage device 21.

(6) The high-temperature water supply equipment in the sixth aspect includes:
In the high-temperature water supply facility according to any one of the first to fifth aspects, the first heat accumulator 21 is disposed on the most downstream side Dd of the plurality of heat accumulators 21, 22, 23 in the water flow direction.

The heat storage body 24 of the first heat storage device 21 is heated by the solar heater 31. Heating the heat storage body 24 with the solar heater 31 makes it easier to heat the heat storage body 24 to a high temperature than heating the heat storage body 24 with the surplus steam heater 49 or the surplus power heater 41. Therefore, if the first heat storage device 21 is arranged on the most downstream side Dd in the water flow direction among the multiple heat storage devices 21, 22, and 23, high-temperature water can be efficiently supplied to the high-temperature water utilization facility.

(7) The high-temperature water supply equipment in the seventh aspect includes:
In the high-temperature water supply facility according to any one of the first to sixth aspects, the heat accumulators 21, 22, and 23 have a plurality of heat storage material particles as the heat storage body 24, and a case 26 that covers the plurality of heat storage material particles. The case 26 has a gas inlet 26i that introduces a gas that circulates the plurality of heat storage material particles within the case 26.

(8) The high-temperature water supply equipment in the eighth aspect includes:
In the high-temperature water supply facility of the seventh aspect, the plurality of heat storage material particles are formed of at least one material selected from the group consisting of silica sand, iron oxide, and silicon carbide.

When a plurality of heat storage particles made of at least one of silica sand, iron oxide, and silicon carbide are used as the heat storage body 24, the purchase cost of the heat storage body 24 can be reduced compared to when molten salt is used as the heat storage body 24. Furthermore, in this case, the heat storage body 24 is easy to handle, and there is no need to strictly control leakage of the heat storage body 24 from the case 26. Therefore, in this embodiment, the manufacturing cost of the high-temperature water supply equipment can be reduced.

(9) In a ninth aspect, the high-temperature water supply equipment comprises:
In the high-temperature water supply facility of any of the first to eighth aspects, a high-temperature water utilization facility is connected to an end of the high-temperature water line 50 on the downstream side Dd in the water flow direction.

(10) In a tenth aspect, the high-temperature water supply equipment comprises:
The high-temperature water supply facility of the ninth aspect further includes a boiler 11 that generates steam, and a steam turbine 12 that is driven by the steam from the boiler 11. The steam turbine 12 is connected to an end of the upstream side Du of the high-temperature water line 50 so that extracted steam from the steam turbine 12 can be introduced into the high-temperature water line 50. The high-temperature water utilization facility is a steam utilization facility 70 that utilizes steam.

10: Steam power generation equipment 11: Boiler 12: Steam turbine 13, 58: Condenser 14, 59: Pump 15: Generator 16: Main power path 18: External system 19: In-house system 21, 21A, 21B: First heat accumulator 22: Second heat accumulator (upstream heat accumulator)
23: Third heat storage device (upstream heat storage device)
24: Heat storage body 25: Fluidized bed 26, 26a, 26A, 26B: Case 26d: Dispersion plate 26t, 26tA, 26tB: Top plate 26tb: Top plate body 26tw: Window 26g: Gas chamber 26f: Fluidized bed chamber 26i: Gas inlet 26o: Gas exhaust port 28: Lid 29: Light receiving section 29a: Cone section 29b: Cylindrical section 30: Heater 31: Solar heater 32: Heliostat 33: Reflector 34: Reflector driver 35: Fixed reflector 41: Surplus power heater 42: Electric heater 42a: Electric heater main body 42b: Heater drive circuit 43: Heat pump 44: Evaporator 45: Compressor 46: Condenser 47: Expander 48: Drive machine 48a: Motor 48b: Motor drive circuit 49: Excess steam heater 50: High temperature water line 51: High heating water line 52: Low heating water line 55: Steam drain recovery line 56: Excess steam line 57: Excess steam recovery line 60: Control device 61: Heating controller 69: Thermometer 70: High temperature water utilization equipment (steam utilization equipment)
71: High heating water usage section 72: Low heating water usage section Du: Upstream side Dd: Downstream side R: Sunlight

Claims (9)

A plurality of heat accumulators each having a heat accumulator;
a heater for heating the heat storage body for each of the plurality of heat storage bodies;
a hot water line through which gaseous or liquid water flows;
A generator,
Equipped with
The high-temperature water line passes through the plurality of heat accumulators so as to be in contact with the heat accumulator, and connects the plurality of heat accumulators in series;
Among the plurality of heat storage devices, the heater of a first heat storage device is a solar heater that uses solar light to heat the heat storage body of the first heat storage device,
the heater of the second heat accumulator, which is disposed upstream of the first heat accumulator in the flow direction of water in the high-temperature water line, has a surplus power heater that uses surplus power of the power generated by the generator to heat the heat accumulator of the second heat accumulator,
The heater of the third heat accumulator, which is disposed upstream of the second heat accumulator in the flow direction of water in the high-temperature water line, has a surplus steam heater that uses steam or steam drain from a steam utilization facility to heat the heat accumulator of the third heat accumulator.
High temperature water supply equipment. The high-temperature water supply system according to claim 1,
The heater of the third heat accumulator includes, together with the surplus steam heater, a surplus power heater that uses surplus power among the power generated by the generator to heat the heat storage body of the third heat accumulator.
High temperature water supply equipment. In the high-temperature water supply system according to claim 1 or 2 ,
The power generating device further includes a heating controller that determines whether the generator can generate the surplus power and drives the surplus power heater with the surplus power if the generator can generate the surplus power.
High temperature water supply equipment. In the high-temperature water supply system according to any one of claims 1 to 3 ,
the surplus power heater has at least one of an electric heater that heats the heat storage body with the surplus power and a heat pump that operates with the surplus power,
The heat pump includes an evaporator that evaporates a liquid medium to form a gaseous medium, a compressor that compresses the gaseous medium, a condenser that condenses the gaseous medium compressed by the compressor to form a liquid medium, an expander that expands the liquid medium, and a driver that is driven by the surplus power to operate the compressor, and the condenser is a heat exchanger that exchanges heat between the gaseous medium and the heat storage body of the upstream heat storage device to cool the gaseous medium while heating the heat storage body.
High temperature water supply equipment. In the high-temperature water supply system according to any one of claims 1 to 4,
The solar heater is a solar guide device having one or more heliostats that guide solar light to a target position, and a reflector that is arranged at the target position and guides solar light from the one or more heliostats to the first heat storage device.
High temperature water supply equipment. In the high-temperature water supply system according to any one of claims 1 to 5 ,
The heat accumulator includes a plurality of heat storage material particles as the heat storage body, and a case that covers the plurality of heat storage material particles,
The case has a gas inlet port for introducing a gas that circulates the plurality of heat storage material particles within the case.
High temperature water supply equipment. The high-temperature water supply system according to claim 6 ,
The plurality of heat storage material particles are formed of at least one material selected from the group consisting of silica sand, iron oxide, and silicon carbide.
High temperature water supply equipment. In the high-temperature water supply system according to any one of claims 1 to 7 ,
A high-temperature water utilization facility is connected to the downstream end of the high-temperature water line in the water flow direction.
High temperature water supply equipment. The high-temperature water supply system according to claim 8 ,
Further comprising a boiler that generates steam and a steam turbine that is driven by steam from the boiler;
The steam turbine is connected to an upstream end of the high-temperature water line so that extraction steam from the steam turbine can be introduced into the high-temperature water line;
The high-temperature water utilization facility is a steam utilization facility that utilizes steam.
High temperature water supply equipment.

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