Title of the invention: Boiler system, power plant, and method of operating the boiler system
Technical field
[0001]
　The present invention relates to a boiler system, a power plant, and a method of operating the boiler system.
Background technology
[0002]
　The heat medium is heated by using the condensed heat of sunlight, which is a natural energy, and the heated heat medium is effectively used to heat the boiler feed water of the thermal power generation device to reduce the boiler fuel supplied to the thermal power generation device. Power plants that reduce carbon dioxide emissions are known.
[0003]
　Since such a power plant uses the condensed heat of sunlight, when the amount of solar radiation changes, the amount of heating of the boiler supply water also changes, and the temperature of the supply water supplied to the boiler also changes. There is a problem of closing it. When the temperature of the supply water supplied to the boiler changes, the temperature of the steam supplied from the boiler to the steam turbine also changes, so that the amount of power generation changes, and there is a possibility that electric power cannot be stably supplied. For this reason, a power plant has been considered in which measures are taken so that the temperature of the supply water supplied to the boiler does not change even if the amount of solar radiation changes (for example, Patent Document 1 and Patent Document 2).
[0004]
　In the plant described in Patent Document 1, a temperature measuring device for measuring the temperature of water discharged from a feed water heater using solar heat is provided, and water using solar heat is supplied based on the temperature of water measured by the temperature measuring device. It controls the flow rate of water flowing into the inlet of the heater.
[0005]
　In the plant described in Patent Document 2, a solar heat heater is provided in which heat exchange is performed between a heat medium heated by sunlight by a heat collector and the inflowing water supply. Further, by adjusting the output of the pump that distributes the heat medium, the flow rate of the heat medium is adjusted, and the temperature of the supply water flowing into the boiler is adjusted.
Prior art literature
Patent documents
[0006]
Patent Document 1: Japanese Patent No. 5723220
Patent Document 2: Japanese Patent No. 6178169
Outline of the invention
Problems to be solved by the invention
[0007]
　However, when the flow rate of the feed water flowing into the inlet of the feed water heater using solar heat is controlled to keep the temperature of the feed water supplied to the boiler constant as in the plant of Patent Document 1, the water supply and heat The temperature of the heat medium to be replaced fluctuates. Therefore, the absorption efficiency of solar heat by the heat medium flowing through the condenser fluctuates, which may reduce the utilization efficiency of solar energy. Therefore, in order to supply the steam generated by the boiler to a steam turbine or the like to obtain a predetermined power generation output, it is necessary to increase the amount of fuel used in the boiler by the amount that the utilization efficiency of solar energy is reduced. Therefore, the running cost may increase.
[0008]
　Further, even when the temperature of the supply water flowing into the boiler is adjusted by adjusting the flow rate of the heat medium heated by sunlight as in the plant of Patent Document 2, the amount of solar energy that can be used depends on the amount of the heat medium. As it changes, it may reduce the efficiency of solar energy utilization. Therefore, as in the case of the plant of Patent Document 1, in order to supply the steam generated by the boiler to a steam turbine or the like to obtain a predetermined power generation output, it is used in the boiler because the utilization efficiency of solar energy is reduced. Since the amount of fuel needs to be increased, the running cost may increase.
[0009]
　The present invention has been made in view of such circumstances, and even when the amount of solar radiation changes, the temperature of steam generated by the boiler can be set to a desired temperature. It is an object of the present invention to provide a possible boiler system, a power plant, and a method of operating the boiler system.
　Another object of the present invention is to provide a boiler system, a power plant, and a method of operating the boiler system, which can reduce the fuel used for heating the water supply in the boiler.
Means to solve problems
[0010]
　In order to solve the above problems, the boiler system, the power plant, and the operation method of the boiler system of the present invention adopt the following means.
　The boiler system according to the first aspect of the present invention utilizes a boiler that generates steam from water supply, a water supply flow path through which the water supply supplied to the boiler flows, and heat generated by condensing sunlight. A solar heating unit that heats the heat medium, a circulation flow path that is provided with the solar heat heating unit and circulates the heat medium at a predetermined constant flow rate, the water supply that flows through the water supply flow path, and the circulation flow path. It is provided with a first heat exchange unit for heat exchange with the heat medium flowing through the boiler, and an adjusting means provided in the boiler and adjusting the temperature of the steam generated by the boiler.
[0011]
　The amount of heat generated by condensing light in the solar heating unit changes according to the change in the amount of solar radiation. When the amount of heat generated in the solar heating section changes, the heating amount of the heat medium in the solar heating section also changes. Further, since the temperature of the circulating heat medium changes as the heating amount of the heat medium changes, the amount of heat exchanged between the heat medium and the water supply also changes in the first heat exchange section. Therefore, the temperature of the water supply supplied to the boiler from the water supply flow path also changes. As the temperature of the supply water supplied to the boiler changes, so does the temperature of the steam generated by the boiler. In this way, when the amount of solar radiation changes, the temperature of the steam generated by the boiler also changes accordingly.
[0012]
　In the above configuration, the boiler is provided with adjusting means for adjusting the temperature of the steam generated by the boiler. As a result, even if the temperature of the water supply changes due to a change in the amount of solar radiation, the temperature of the steam generated by the boiler can be adjusted by the adjusting means provided in the boiler. Therefore, even when the amount of solar radiation changes, the temperature of the steam generated by the boiler can be set to a desired temperature. The temperature of the steam generated by the boiler includes, for example, the temperature of the steam supplied from the boiler to the steam turbine.
[0013]
　Further, in the above configuration, the boiler is provided with an adjusting means for adjusting the temperature of the steam generated by the boiler. That is, the circulation flow path for circulating the heat medium is not provided with an adjusting means for adjusting the temperature of the heat medium. As a result, in order to adjust the temperature of the circulation flow path, such as a configuration in which the temperature of the heat medium is positively reduced in order to maintain the temperature of the heat medium after heating when the amount of solar radiation changes. The configuration does not exist. Therefore, substantially all of the heat obtained by heating the heat medium from the energy generated by condensing sunlight in the solar heating unit can be used for heating the supply water supplied to the boiler. In this way, even if the amount of solar radiation changes, almost all of the heat obtained by heating the heat medium from the energy generated by condensing the sunlight can be used for heating the water supply. Therefore, compared to the case where the energy obtained from sunlight is positively reduced when the amount of solar radiation changes to maintain the temperature of the heat medium after heating, the water supply to the boiler is increased. The amount of heat transfer can be increased to raise the temperature of the water supply. Therefore, it is possible to suppress a decrease in the utilization efficiency of solar energy and reduce the fuel used for heating the water supply in the boiler.
　The configuration provided with a device or the like that positively reduces the heat obtained from sunlight includes, for example, a configuration provided with an adjusting means for adjusting the temperature of the heat medium by changing the circulation flow rate of the heat medium, or the heat medium. An example is a configuration in which an adjusting means for adjusting the amount of water supplied for heat exchange is provided.
　Further, in the above configuration, the circulation flow rate of the heat medium is set to a predetermined constant flow rate. For a predetermined constant flow rate, for example, under the condition where the solar energy is the highest, the temperature of the heat medium obtained by heating the heat medium from the energy generated by condensing sunlight in the solar heating unit is the temperature of the solar heating unit. It may be the flow rate that reaches the design temperature of.
[0014]
　Further, in the boiler system according to the first aspect of the present invention, in the circulation flow path, all of the heat medium heated by the solar heat heating unit is supplied to the first heat exchange unit, and the first heat exchange unit is supplied. All of the heat mediums heat-exchanged in the above may be supplied to the solar heating unit.
[0015]
　In the above configuration, all of the heat medium heated by the solar heat exchange unit is supplied to the first heat exchange unit, and all of the heat exchange heat exchanged by the first heat exchange unit is supplied to the solar heat exchange unit. This ensures that there is no configuration in the circulation flow path that positively reduces the heat obtained by heating the heat medium with the energy generated by condensing sunlight in the solar heating unit. Can be done. Therefore, substantially all of the heat obtained by heating the heat medium from the solar energy in the solar heat heating unit can be reliably used for heating the water supply in the first heat exchange unit.
[0016]
　Further, in the boiler system according to the first aspect of the present invention, the boiler includes a downstream superheater that superheats the steam, an upstream superheater provided on the upstream side of the downstream superheater and superheats the steam, and the above. A superheater that is provided between the downstream boiler and the upstream boiler to reduce the temperature of the steam supplied, and the water supply on the upstream side of the upstream boiler is extracted to the superheater. A spray water adjusting means for adjusting the amount of the water supplied to the superheater in the spray water supply flow path, which comprises a spray water supply flow path for supplying fuel and a fuel supply path for supplying fuel to the burner. Is provided, and the fuel supply path is provided with fuel adjusting means for adjusting the amount of fuel supplied to the burner, and the adjusting means includes the spray water adjusting means and the fuel adjusting means.
[0017]
　In the above configuration, the temperature of the steam generated in the boiler is adjusted by controlling the spray water adjusting means and the fuel adjusting means. As a result, even when the amount of solar radiation changes and the temperature of the water supply changes, the temperature of the steam generated by the boiler can be surely adjusted in the boiler.
　It is more preferable that the spray water adjusting means is controlled so that the temperature of the steam generated by the boiler becomes a desired temperature based on the temperature of the steam heated by the downstream superheater. Further, it is more preferable that the fuel adjusting means is controlled so that the temperature of the steam generated by the boiler becomes a desired temperature based on the temperature of the steam supplied to the superheat reducer.
[0018]
　Further, in the boiler system according to the first aspect of the present invention, the boiler is supplied to the water supply heating unit and the water supply heating unit which are provided on the upstream side of the upstream superheater and heat the supplied water. The fuel adjusting means may be controlled based on the water supply thermometer side means for measuring the temperature of the water supply and the water supply temperature measured by the water supply thermometer side means.
[0019]
　In the above configuration, the water supply thermometer side means for measuring the temperature of the supply water supplied to the water supply heating unit is provided, and the fuel adjusting means is controlled based on the temperature of the water supply measured by the water supply thermometer side means. The water supply heating unit is provided on the upstream side of the downstream superheater, the upstream superheater, and the like. That is, the water supply heating unit is provided at a position closer to the first heat exchange unit than the downstream superheater, the upstream superheater, and the like. As a result, when the amount of solar radiation changes, the temperature of the water supplied to the water supply heating unit changes faster than the configuration provided on the downstream side of the upstream superheater 34 or the like. Therefore, by controlling the fuel adjusting means based on the temperature of the supply water supplied to the water supply heating unit, it is possible to respond to the change in the amount of solar radiation more quickly. Therefore, the fuel adjusting means can be controlled more accurately so that the temperature of the steam generated by the boiler becomes a desired temperature.
[0020]
　Further, the boiler system according to the first aspect of the present invention includes a heat medium temperature measuring means for measuring the temperature of the heat medium supplied from the solar heating unit to the first heat exchange unit, and measures the heat medium temperature. The fuel adjusting means may be controlled based on the temperature of the heat medium measured by the means.
[0021]
　In the above configuration, a heat medium temperature measuring means for measuring the temperature of the heat medium supplied from the solar heat heating unit to the first heat exchange part is provided, and the fuel is based on the temperature of the heat medium measured by the heat medium temperature measuring means. It controls the adjustment means. When the amount of solar radiation changes, the amount of heating of the heat medium by the heat generated by condensing sunlight in the solar heating unit changes. Therefore, the temperature of the heat medium supplied from the solar heat heating unit to the first heat exchange unit also changes. Therefore, the temperature of the heat medium supplied from the solar heat heating unit to the first heat exchange unit changes rapidly with respect to the change in the amount of solar radiation. Therefore, by controlling the fuel adjusting means based on the temperature of the heat medium supplied from the solar heat heating unit to the first heat exchange unit, it is possible to respond to the change in the amount of solar radiation more quickly. Therefore, the fuel adjusting means can be controlled more accurately so that the temperature of the steam generated by the boiler becomes a desired temperature.
[0022]
　Further, the boiler system according to the first aspect of the present invention has a first bypass flow path that bypasses the water supply flow path, and whether the water supply flows through the water supply flow path or the first bypass flow path. The first heat exchange unit includes a switching means for switching and a heat medium temperature measuring means for measuring the temperature of the heat medium supplied from the solar heat heating unit to the first heat exchange unit. The switching means is provided in the bypass flow path so that the water supply does not flow into the first bypass flow path when the temperature of the heat medium measured by the heat medium temperature measuring means is lower than a predetermined value. May be controlled.
[0023]
　In the above configuration, when the temperature of the heat medium supplied to the first heat exchange unit is lower than a predetermined value, the switching means is controlled so that the water supply does not flow into the first bypass flow path. That is, when the temperature of the heat medium is lower than a predetermined value, water is not supplied to the first heat exchange section. As a result, when the temperature of the heat medium is lower than a predetermined value and the water supply cannot be suitably heated by the heat medium, the water supply can be prevented from being supplied to the first heat exchange unit. The predetermined value includes, for example, the temperature of the water supply supplied to the first heat exchange unit. If the temperature of the heat medium supplied to the first heat exchange unit is lower than the temperature of the water supply supplied to the first heat exchange unit, the heat medium may cool the water supply. Therefore, in such a case, cooling of the water supply can be suppressed by preventing the water supply from being supplied to the first heat exchange unit.
[0024]
　In addition, the boiler system according to the first aspect of the present invention is provided in the water supply flow path and exchanges heat between the steam extracted from the steam turbine driven by the steam generated by the boiler and the water supply. A heat exchange unit and a second bypass flow path provided so as to bypass the second heat exchange unit and provided with the first heat exchange unit are provided, and the second bypass flow path is provided in the boiler. A part of the supplied water may be distributed.
[0025]
　In the above configuration, the first heat exchange section is provided in the second bypass flow path provided so as to bypass the second heat exchange section that heats the water supply by the steam extracted from the steam turbine, and the second bypass flow path is provided. Part of the water supply is distributed. That is, the water supply is heated by the first heat exchange unit and the second heat exchange unit provided in parallel with the first heat exchange unit. As a result, the amount of water supplied to be heated by the second heat exchange unit can be reduced, so that the amount of steam extracted from the steam turbine can be reduced. Therefore, the energy obtained by the steam turbine can be increased.
[0026]
　Further, the boiler system according to the first aspect of the present invention includes an air-water separator provided between the solar heat heating unit and the first heat exchange unit, and the heat medium is water or steam. The steam separator may separate the supplied water and steam, and may supply the separated steam to the first heat exchange section.
[0027]
　In the above configuration, inexpensive water or steam is used as the heat medium. Therefore, the cost of the heat medium can be reduced.
　Further, a steam separator is provided, and only steam is supplied from the steam separator to the first heat exchange unit. As a result, in the first heat exchange section, the water supply can be heated only by the high-temperature steam, so that the water supply can be suitably heated.
[0028]
　The power plant according to the first aspect of the present invention includes the boiler system according to any one of the above, and a power generation unit that generates power from the steam generated by the boiler.
[0029]
　In the above configuration, the temperature of the steam generated by the boiler can be set to a desired temperature, so that the amount of power generated by the power generation unit can be set to the desired amount of power generation. Further, when the temperature of the steam generated by the boiler is constant, the amount of power generated by the power generation unit can be constant, so that the electric power can be stably supplied.
[0030]
　The operation method of the boiler system according to the first aspect of the present invention utilizes a steam generation step of generating steam from water supplied via a water supply flow path and heat generated by condensing sunlight in the boiler. Then, a heat medium heating step of heating a heat medium that circulates in the circulation flow path at a predetermined constant flow rate, heat exchange between the water supply that flows through the water supply flow path and the heat medium that flows through the circulation flow path. It is provided with a heat exchange step for adjusting the temperature of the steam generated in the boiler by an adjusting means provided in the boiler.
Effect of the invention
[0031]
　According to the present invention, the temperature of the steam generated by the boiler can be set to a desired temperature even when the amount of solar radiation is changed.
　Also, the fuel used to heat the water supply in the boiler can be reduced.
A brief description of the drawing
[0032]
FIG. 1 is a schematic configuration diagram of a power plant according to the first embodiment of the present invention.
FIG. 2 is a flowchart showing a process performed by a control device provided in a power plant according to the first embodiment of the present invention.
FIG. 3 is a flowchart showing a process performed by a control device provided in a power plant according to the first embodiment of the present invention, and is a flowchart showing a continuation of FIG.
FIG. 4 is a schematic configuration diagram of a power plant according to a second embodiment of the present invention.
FIG. 5 is a schematic configuration diagram of a solar heat-utilizing feed water heater provided in a power plant according to a third embodiment of the present invention.
Mode for carrying out the invention
[0033]
　Hereinafter, an embodiment of the boiler system and the power plant according to the present invention and the operation method of the boiler system will be described with reference to the drawings.
[0034]
[First Embodiment]
　Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. 1 to 3.
　The power plant 100 includes a boiler system 1 that generates steam, and a power generation unit 2 that generates power by rotating a steam turbine 7 with the steam generated by the boiler system 1.
　The boiler system 1 heats the boiler 3 that generates steam from the water supply, the water supply preheating unit (second heat exchange unit) 4 that heats the water supply to the boiler 3 by the steam extracted from the steam turbine 7 described later, and sunlight. A solar heat utilization heating unit 5 that heats the water supply supplied to the boiler 3 by exchanging heat with a heated heat medium using the energy generated by condensing the energy, and a control device (not shown) that controls various devices. , Is equipped.
　The power generation unit 2 includes a steam turbine 7 that is rotationally driven by the steam generated by the boiler 3, and a generator 8 that generates electricity by the rotational driving force of the steam turbine 7.
[0035]
　The boiler 3 includes a fireplace 30, a burner 31 provided on the wall of the fireplace 30, and a flue 32 through which the combustion gas generated by the fireplace 30 flows.
　The burner 31 forms a flame in the furnace 30 by burning the fuel supplied through the fuel pipe (fuel supply path) 33. The fuel pipe 33 is provided with a fuel flow rate adjusting valve (fuel adjusting means) 33a for adjusting the flow rate of the fuel flowing through the inside. The fuel flow rate adjusting valve 33a can adjust the flow rate of the fuel supplied to the burner 31 by adjusting the opening degree.
[0036]
　In the flue 32, in the example of the present embodiment, in order from the upstream side of the combustion gas flow, at least the upstream side superheater (upstream superheater) 34, the final superheater (superheater) 35, and the final superheater A (downstream superheater) 36, a reheater 37, and an economizer (water supply heating unit) 38 are provided. In addition, other heat exchangers may be provided at appropriate positions. The upstream superheater 34, the final superheater 36, the reheater 37, and the economizer 38 function as heat exchangers that use the heat recovered from the combustion gas to heat the water supply (or steam) circulating inside. To do.
[0037]
　In water supply or steam flow, the economizer 38 is provided on the most upstream side of the heat exchangers provided in the boiler 3. The downstream end of the economizer 38 is connected to the upstream end of the upstream superheater 34 via the fifth water supply pipe 24. The water supplied through the fifth water supply pipe 24 becomes saturated steam due to the heat from the fireplace 30, and is supplied to the upstream superheater 34. The fifth water supply pipe 24 is provided with a second water supply temperature measuring instrument 24a that measures the temperature Te of the water supply flowing in the fifth water supply pipe 24. The second water supply temperature measuring device 24a transmits the measured temperature to the control device. A spray water pipe (spray water supply flow path) 39 branches from an intermediate position of the fifth water supply pipe 24. The spray water pipe 39 extracts a part of the water supply flowing through the fifth water supply pipe 24 and supplies the extracted water into the final overheat reducer 35. The spray water pipe 39 is provided with a spray water amount adjusting valve (spray water adjusting means) 39a for adjusting the flow rate of water flowing through the inside. The amount of water supplied to the final overheat reducer 35 can be adjusted by adjusting the opening degree of the spray water amount adjusting valve 39a. A heat exchanger (evaporator) (not shown) may be provided in the middle of the fifth water supply pipe 24 to evaporate the water supply by the heat from the fireplace 30. Further, the spray water pipe 39 may supply the extracted water to the pipe on the upstream side of the final overheat reducer 35 (that is, the first steam pipe 11).
[0038]
　The downstream end of the upstream superheater 34 is connected to the final superheater 35 via the first steam pipe 11. The first steam pipe 11 is provided with a first steam temperature measuring instrument 11a for measuring the temperature Ts of steam flowing in the first steam pipe 11. The first steam temperature measuring instrument 11a transmits the measured temperature to the control device.
[0039]
　The final superheater 35 is connected to the upstream end of the final superheater 36 via a second steam pipe 12. The downstream end of the final superheater 36 is connected to a high-pressure steam turbine (steam turbine) 70, which will be described later, via a third steam pipe 13. The third steam pipe 13 is provided with a third steam temperature measuring instrument 13a for measuring the temperature Tm of the steam flowing in the third steam pipe 13. Further, the third steam pipe 13 is provided with a steam pressure measuring instrument 13b for measuring the pressure Pm of the steam flowing in the third steam pipe 13. The third steam temperature measuring instrument 13a and the steam pressure measuring instrument 13b transmit the measured temperature or pressure to the control device. Further, the third steam pipe 13 is provided with a steam flow rate adjusting valve 13c on the downstream side of the third steam temperature measuring instrument 13a and the steam pressure measuring instrument 13b. The steam flow rate adjusting valve 13c adjusts the flow rate of steam flowing through the inside and supplied to the high-pressure steam turbine 70 by adjusting the opening degree.
[0040]
　The upstream end of the reheater 37 is connected to the downstream end of the high-pressure steam turbine 70 via a fourth steam pipe 14. Further, the downstream end of the reheater 37 is connected to the medium pressure steam turbine 71, which will be described later, via the fifth steam pipe 15.
[0041]
　In the present embodiment, the steam turbine 7 includes, for example, a high-pressure steam turbine 70, a medium-pressure steam turbine 71, and a low-pressure steam turbine 72 that are coaxially connected. The high-pressure steam turbine 70, the medium-pressure steam turbine 71, and the low-pressure steam turbine 72 are each rotationally driven by the steam supplied from the boiler 3. The downstream end of the medium-pressure steam turbine 71 is connected to the low-pressure steam turbine 72 via a sixth steam pipe 16. Further, the downstream end of the low-pressure steam turbine 72 is connected to the condenser 73 via the seventh steam pipe 17. In the condenser 73, the supplied steam is condensed to condense the water.
[0042]
　The generator 8 is connected to a rotating shaft 74 shared by the high-pressure steam turbine 70, the medium-pressure steam turbine 71, and the low-pressure steam turbine 72. The generator 8 generates electric power by converting the rotational driving force transmitted from each steam turbine via the rotary shaft 74 into electric power.
[0043]
　The water supply preheating unit 4 includes a low-pressure water supply heater 40 that heats the water supply with the steam extracted from the low-pressure steam turbine 72, a medium-pressure water supply heater 41 that heats the water supply with the steam extracted from the medium-pressure steam turbine 71, and a high-pressure steam turbine 70. It is provided with a high-pressure water supply heater 42 that heats the water supply with the steam extracted from the turbine.
[0044]
　The low-pressure water supply heater 40 is arranged at the most upstream side of the water supply flow among the three water supply heaters 40, 41, and 42. The upstream end of the low-pressure water supply heater 40 is connected to the condenser 73 via the first water supply pipe 20. The first water supply pipe 20 is provided with a condensate pump 20a for circulating water supply. Further, the low-pressure water supply heater 40 is connected to the low-pressure steam turbine 72 via the first bleeding pipe 25. The low-pressure water supply heater 40 exchanges heat between the water supply and the steam supplied via the first bleed air pipe 25.
[0045]
　The low-pressure water supply heater 40 and the medium-pressure water supply heater 41 are connected via a second water supply pipe 21. The second water supply pipe 21 is provided with a water supply pump 21a that boosts and distributes the water supply. The medium-pressure water supply heater 41 and the high-pressure water supply heater 42 are connected via a third water supply pipe 22. Further, the medium pressure water supply heater 41 is connected to the medium pressure steam turbine 71 via the second bleeding pipe 26. The medium-pressure water supply heater 41 exchanges heat between the water supply and the steam supplied via the second bleed air pipe 26.
[0046]
　The downstream end of the high-pressure water supply heater 42 is connected to the upstream end of the economizer 38 via the fourth water supply pipe (water supply flow path) 23. A first water supply on-off valve (switching means) 23a is provided at an intermediate position of the fourth water supply pipe 23. The first water supply on-off valve 23a is an on-off valve. Further, a bypass pipe (first bypass flow path) 43 is provided so as to bypass the first water supply on-off valve 23a from an intermediate position of the fourth water supply pipe 23. That is, the upstream end of the bypass pipe 43 is connected to the upstream side of the first water supply on-off valve 23a of the fourth water supply pipe 23. Further, the downstream end of the bypass pipe 43 is connected to the downstream side of the first water supply on-off valve 23a of the fourth water supply pipe 23. The bypass pipe 43 is provided with a second water supply on-off valve (switching means) 43a. The second water supply on-off valve 43a is an on-off valve. Further, the fourth water supply pipe 23 is provided with a first water supply temperature measuring instrument (water supply thermometer side means) 23b. The first water supply temperature measuring instrument 23b is provided on the downstream side of the fourth water supply pipe 23 with respect to the connection portion with the downstream end of the bypass pipe 43. The first water supply temperature measuring instrument 23b measures the temperature Th of the water supply flowing inside the fourth water supply pipe 23 on the downstream side of the connection portion with the downstream end of the bypass pipe 43. That is, the temperature of the water supply immediately before being supplied to the economizer 38 is measured. The first water supply temperature measuring instrument 23b transmits the measured temperature to the control device.
　Further, the high-pressure water supply heater 42 is connected to the high-pressure steam turbine 70 via the third bleeding pipe 27. The high-pressure water supply heater 42 exchanges heat between the water supply and the steam supplied via the third bleed air pipe 27.
[0047]
　The solar heat utilization heating unit 5 includes a circulation flow path 50 in which a heat medium circulates, a solar heat collector (solar heat heating unit) 51 provided in the circulation flow path 50, and a solar heat utilization water supply heater (solar heat utilization heating unit) provided in the circulation flow path 50. First heat exchange unit) 52 and. Further, in the circulation flow path 50, a heat medium temperature measuring instrument (heat medium temperature measurement) provided between the downstream end of the heat medium pump 53 for circulating the heat medium and the solar heat-utilizing feed water heater 52 and the solar heat collector 51 is provided. Means) 54 is provided. The heat medium temperature measuring instrument 54 transmits the measured temperature to the control device. As the heat medium that circulates in the circulation flow path 50, for example, in the present embodiment, an oil-based heat medium that maintains the liquid phase even when the temperature rises and does not easily change the phase is used. The heat medium is not limited to this, and may be, for example, a molten salt-based heat medium or the like.
[0048]
　The solar heat collector 51 heats the heat medium by utilizing the energy generated by condensing sunlight. The solar heat collector 51 may be, for example, a Fresnel type (a method of heating a heat medium with a flat surface or a small curved surface reflector) or a trough type (a method of heating a heat medium with a curved surface reflector). Good. Moreover, it may be a tower type. In the present embodiment, for example, a plurality of solar heat collectors 51 are provided in parallel, and three solar heat collectors 51 are provided. The number of solar heat collectors 51 is not limited to this. It may be one or two. Further, there may be a plurality of 4 or more units.
[0049]
　The solar heat utilization feed water heater 52 is provided between the solar heat collector 51 and the heat medium pump 53. The feed water heater 52 using solar heat exchanges heat between the heat medium heated by the solar heat collector 51 and the feed water flowing through the bypass pipe 43.
　The heat medium temperature measuring instrument 54 measures the temperature Tо of the heat medium immediately after being heated by the solar heat collector 51 among the heat media circulating in the circulation flow path 50.
[0050]
　The circulation flow path 50 is not provided with a device for adjusting the flow rate of the heat medium. In the circulation flow path 50, all of the heat medium heated by the solar heat collector 51 is supplied to the solar heat-utilizing feed water heater 52 and circulates at a predetermined constant flow rate. Further, all of the heat media exchanged by the solar heat-utilizing feed water heater 52 are introduced into the heat medium pump 53. Further, all the heat medium discharged from the heat medium pump 53 is supplied to the solar heat collector 51. That is, the circulation flow path 50 is a closed circuit.
[0051]
　The control device includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a computer-readable storage medium, and the like. Then, as an example, a series of processes for realizing various functions are stored in a storage medium or the like in the form of a program, and the CPU reads this program into a RAM or the like to execute information processing / arithmetic processing. As a result, various functions are realized. The program is installed in a ROM or other storage medium in advance, is provided in a state of being stored in a computer-readable storage medium, or is distributed via a wired or wireless communication means. Etc. may be applied. Computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, semiconductor memories, and the like.
[0052]
　The control device controls the open / closed state or opening degree of each valve. The control device controls the drive and stop of each pump. The control device performs steam temperature control processing so that the temperature of the steam supplied from the final superheater 36 to the high-pressure steam turbine 70 becomes a predetermined temperature based on the temperature measured by each temperature measuring device.
[0053]
　The steam temperature control process performed by the control device will be described below with reference to the flowcharts of FIGS. 2 and 3.
　When the steam temperature control process is started, the control device is first discharged from the target temperature of the steam temperature Tm of the steam discharged from the final superheater 36 (that is, the steam discharged from the boiler 3) and from the final superheater 36. A target pressure of steam pressure Pm of steam (that is, steam discharged from the boiler 3) is set (S1). The target temperature of the steam temperature Tm and the target pressure of the steam pressure Pm are set to, for example, the temperature and pressure when the high-pressure steam turbine 70 rotates at a rated value. Next, the control device proceeds to S2 to determine whether or not the temperature Th of the water supply immediately before being supplied to the economizer 38 has changed, and the heat medium immediately after being heated by the solar heat collector 51. It is determined whether or not the temperature Tо of the above is changing. If it is determined that either one has changed, the control device determines that the amount of solar radiation has changed and proceeds to S3. If it is determined that neither value has changed, it is determined that there is no change in the amount of solar radiation, and S2 is repeated again after a predetermined time.
[0054]
　In S3, the control device determines whether or not the water supply temperature Th is smaller than the first predetermined value, and also determines whether or not the heat medium temperature Tо is smaller than the second predetermined value. If it is determined that either one is smaller than the predetermined value, it is determined that the amount of solar radiation is reduced and the water supply is not properly heated by the heat medium, and the process proceeds to S4. If it is determined that both of them are larger than the predetermined values, the control device determines that the heating of the water supply by the heat medium is preferably performed, and proceeds to S7. The first predetermined value and the second predetermined value are different from each other when, for example, heat exchange is performed by the solar heat utilization feed water heater 52 and the power generation unit 2 performs a predetermined minimum power generation output (for example, 25% load). The temperature Th of the feed water immediately before being supplied to the economizer 38 and the temperature Tо of the heat medium immediately after being heated by the solar heat collector 51 can be used. Further, in order to suppress the cooling of the feed water by the heat medium in the feed water heater 52 using solar heat, the first predetermined value and the second predetermined value are, for example, the temperature of the feed water immediately before the heat exchange is performed in the feed water heater 52 using solar heat. May be used.
[0055]
　In S4, the control device sets the first water supply on-off valve 23a from the closed state to the open state and the second water supply on-off valve 43a from the open state to the closed state. Next, the control device stops the heat medium pump 53 (S5). When the heat medium pump 53 is stopped, the control device then proceeds to S6 and determines whether or not the heat medium temperature Tо is equal to or higher than the second predetermined value by α (second predetermined value + α). When it is determined that the value is equal to or greater than the second predetermined value + α, it is determined that the amount of solar radiation increases and the amount of solar radiation is such that the water supply can be heated by the heat medium. Then, first, the heat medium pump 53 is started. Next, the second water supply on-off valve 43a is changed from the closed state to the open state, and the first water supply on-off valve 23a is changed from the open state to the closed state. Then, proceed to S7. If it is determined in S6 that it is smaller than the second predetermined value + α, it is determined that the amount of solar radiation is not suitable for heating the water supply with the heat medium, and S6 is repeated again after a predetermined time. In this way, by setting the temperature at which the heating of the water supply water by the heat medium is restarted to a temperature α minutes higher than the second predetermined value, hysteresis can be provided, so that chattering can be suppressed. For example, α may use an appropriate value between 0.5 and 10 ° C.
[0056]
　Proceeding to S7, the control device calculates an estimated amount of the flow rate of the fuel to be charged into the boiler 3 based on the water supply temperature Th. Next, the process proceeds to S8, and the opening degree of the fuel flow rate adjusting valve 33a is controlled so that the fuel flow rate estimated in S7 is used as the preceding control, and the flow rate of the fuel supplied to the burner 31 is adjusted. The estimated amount of the flow rate of the fuel input to the boiler 3 may be set as an internal function based on, for example, the steam supply flow rate to the high-pressure steam turbine 70 (or the power generation output of the power generation unit 2) or the water supply temperature Th. Since the opening degree of the fuel flow rate adjusting valve 33a is also controlled in S10 described later, the control of the opening degree of the fuel flow rate adjusting valve 33a performed in S8 is a preceding control with respect to the control in S10.
[0057]
　When the advance control of the fuel flow rate adjusting valve 33a is completed, the control device executes the control process of the steam temperature in the boiler 3 (adjustment step). Specifically, first, in S9, the opening degree of the spray water amount adjusting valve 39a is controlled to adjust the amount of spray water supplied to the final overheat reducer 35. Specifically, in S9, the control device controls the opening degree of the spray water amount adjusting valve 39a so that the steam temperature Tm becomes the target temperature.
　Next, the control device proceeds to S10, controls the opening degree of the fuel flow rate adjusting valve 33a, and adjusts the flow rate of the fuel supplied to the burner 31. Specifically, in S10, the control device controls the opening degree of the fuel flow rate adjusting valve 33a so that the steam temperature Ts immediately before the final superheat reducing device 35 becomes a predetermined temperature.
[0058]
　Next, the control device proceeds to S11 and determines whether or not the steam temperature Tm output from the boiler 3 is the target steam temperature. If it is determined that the steam temperature Tm is the target steam temperature, the process proceeds to S12. If it is determined that the steam temperature Tm is not the target steam temperature, the process returns to S9. In S12, the control device determines whether or not the water supply temperature Th is smaller than the third predetermined value. The third predetermined value is set to, for example, the value of the temperature at which the water supply evaporates in the economizer 38. If it is determined that the value is equal to or higher than the third predetermined value, it is determined that the water supply is vaporized in the economizer 38, and the process returns to S3. It is determined again whether or not the temperature Tо is smaller than the second predetermined value, and the necessary steps are performed. If it is determined that the value is smaller than the third predetermined value, the process proceeds to S13. In S13, since the steam temperature Tm and the steam pressure Pm are maintained, the opening degree of the steam flow rate adjusting valve 13c can be maintained so as not to change. When the opening degree of the steam flow rate adjusting valve 13c is maintained, the control device ends this process.
[0059]
　Next, the flow of water and steam in this embodiment will be described.
　The water supply discharged from the condenser 73 is supplied to the condenser pump 20a. The water supply discharged from the condensate pump 20a is first introduced into the low-pressure water supply heater 40. In the low-pressure water supply heater 40, the water supply is heated by heat exchange between the water supply introduced through the first water supply pipe 20 and the steam introduced from the low-pressure turbine via the first bleeding pipe 25. The water supply heated by the low-pressure water supply heater 40 is discharged from the low-pressure water supply heater 40 and supplied to the water supply pump 21a to boost the pressure. The water supply discharged from the water supply pump 21a is introduced into the medium pressure water supply heater 41. In the medium-pressure water supply heater 41, the water supply is heated by heat exchange between the water supply introduced through the second water supply pipe 21 and the steam introduced from the medium-pressure turbine via the second bleeding pipe 26. .. The water supply heated by the medium-pressure water supply heater 41 is discharged from the medium-pressure water supply heater 41 and introduced into the high-pressure water supply heater 42. In the high-pressure water supply heater 42, the water supply is heated by heat exchange between the water supply introduced through the third water supply pipe 22 and the steam introduced from the high-pressure turbine via the third air extraction pipe 27. The water supply heated by the high-pressure water supply heater 42 is discharged from the high-pressure water supply heater 42 to the fourth water supply pipe 23. The water supply circulating in the fourth water supply pipe 23 has been raised to about 290 to 300 ° C. (the temperature is an example of this embodiment and is not limited to this).
[0060]
　When the first water supply on-off valve 23a is in the open state and the second water supply on-off valve 43a is in the closed state, the water supplied through the fourth water supply pipe 23 is directly sent to the economizer 38 provided in the boiler 3. Be supplied. On the other hand, in the water supply flowing through the fourth water supply pipe 23, when the first water supply on-off valve 23a is in the closed state and the second water supply on-off valve 43a is in the open state, the entire flow rate flows into the bypass pipe 43. The feed water flowing through the bypass pipe 43 is introduced into the feed water heater 52 using solar heat. In the feed water heater 52 utilizing solar heat, the feed water is heated by heat exchange between the feed water and the heat medium flowing through the circulation flow path 50 (heat exchange step). The water supply heated by the solar heat-utilizing feed water heater 52 is discharged from the solar heat-utilizing feed water heater 52 and flows into the fourth water supply pipe 23 again via the bypass pipe 43. The water supplied to the fourth pipe is supplied to the economizer 38 provided in the boiler 3. The water supply temperature Th at this time has been raised to about 300 to 310 ° C. (the temperature is an example of this embodiment and is not limited to this).
[0061]
　The water supplied to the economizer 38 is heated by exchanging heat with the combustion gas in the boiler 3 in the economizer 38. The water supplied heated by the economizer 38 is discharged from the economizer 38 and supplied to the upstream superheater 34 via the fifth water supply pipe 24. The water supplied through the fifth water supply pipe 24 becomes saturated steam due to the heat from the fireplace 30, and is supplied to the upstream superheater 34. A heat exchanger (evaporator) (not shown) may be provided in the middle of the fifth water supply pipe 24 to evaporate the water supply. In the upstream superheater 34, the steam is superheated by heat exchange between the steam introduced through the fifth water supply pipe 24 and the combustion gas. The steam superheated by the upstream superheater 34 is discharged from the upstream superheater 34 and introduced into the final superheater 35. In the final overheat reducer 35, the temperature of the steam is adjusted by spraying the spray water extracted from the fifth water supply pipe 24 onto the steam. The steam discharged from the final superheater 35 is introduced into the final superheater 36 via the second steam pipe 12. In the final superheater 36, the steam is superheated by heat exchange between the steam introduced through the second steam pipe 12 and the combustion gas. The steam superheated by the final superheater 36 is discharged from the final superheater 36 and output from the boiler 3 (steam generation step).
[0062]
　The steam discharged from the final superheater 36 is supplied to the high-pressure steam turbine 70 via the third steam pipe 13. The steam supplied to the high-pressure steam turbine 70 rotates the high-pressure steam turbine 70 and is discharged from the high-pressure steam turbine 70. The steam discharged from the high-pressure steam turbine 70 is supplied to the reheater 37 via the fourth steam pipe 14. That is, it is introduced into the boiler 3 again. In the reheater 37, the steam is heated by heat exchange between the steam introduced through the fourth steam pipe 14 and the combustion gas. The steam heated by the reheater 37 is discharged from the reheater 37 and is output again from the boiler 3.
[0063]
　The steam output from the reheater 37 is supplied to the medium pressure steam turbine 71 via the fifth steam pipe 15. The steam supplied to the medium-pressure steam turbine 71 rotates the medium-pressure steam turbine 71 and is discharged from the medium-pressure steam turbine 71. The steam discharged from the medium-pressure steam turbine 71 is supplied to the low-pressure steam turbine 72 via the sixth steam pipe 16. The steam supplied to the low-pressure steam turbine 72 rotates the low-pressure steam turbine 72 and is discharged from the low-pressure steam turbine 72. The steam discharged from the low-pressure steam turbine 72 is supplied to the condenser 73 via the seventh steam pipe 17. The steam supplied to the condenser 73 is condensed by being cooled. The condensed steam (that is, water) becomes water supply and is introduced into the condensate pump 20a.
[0064]
　Next, the flow of the heat medium in this embodiment will be described.
　The heat medium discharged from the heat medium pump 53 passes through the circulation flow path 50 and is introduced into the solar heat collector 51. The solar heat collector 51 heats the heat medium from the energy generated by condensing sunlight (heat medium heating step). The heat medium discharged from the solar heat collector 51 flows through the circulation flow path 50 and is introduced into the solar heat-utilizing feed water heater 52. In the solar heat utilization feed water heater 52, heat exchange between the heat medium and the feed water is performed (heat exchange step). The heat medium temperature To at this time is raised to about 320 to 350 ° C. (the temperature is an example of this embodiment and is not limited to this). The heat medium discharged from the solar heat utilization feed water heater 52 is supplied to the heat medium pump 53.
[0065]
　According to this embodiment, the following effects are exhibited.
[0066]
　The amount of energy generated by condensing with the solar heat collector 51 changes according to the change in the amount of solar radiation. When the amount of energy generated by the solar heat collector 51 changes, the amount of heat of the heat medium in the solar heat collector 51 also changes. Further, since the temperature of the circulating heat medium changes as the heating amount of the heat medium changes, the amount of heat exchanged between the heat medium and the feed water in the solar heat-utilizing feed water heater 52 also changes. Therefore, the temperature of the supply water supplied from the fourth water supply pipe 23 to the boiler 3 also changes. In the conventional boiler, the temperature of the steam generated by the boiler 3 also changes as the temperature of the supply water supplied to the boiler 3 changes. In this way, when the amount of solar radiation changes, the temperature of the steam generated in the conventional boiler 3 also changes accordingly.
[0067]
　In the present embodiment, the temperature of the steam generated in the boiler 3 is adjusted by adjusting both the amount of spray water supplied to the final overheat reducer 35 and the amount of fuel supplied to the boiler 3 by the control device. Is adjusted by suppressing the occurrence of time delay.
　The temperature of the steam generated in the boiler 3 is controlled by the amount of spray water supplied to the final superheat reducer 35, and is controlled with little time delay and excellent responsiveness. When the amount of spray water increases, the steam flow rate introduced into the upstream superheater 34 decreases and the steam temperature at the inlet of the final superheater 35 also fluctuates. By adjusting the amount, the essential heat balance in the boiler 3 is performed, and the steam temperature generated can be controlled by controlling the long-term balance fluctuation.
　As a result, even if the amount of solar radiation changes and the temperature of the supply water supplied to the boiler 3 changes, the temperature of the steam generated by the boiler 3 is quickly set to a desired temperature, and the temperature of the steam generated by the boiler 3 is quickly changed to a desired temperature from the boiler 3. Can be output. Further, since the temperature of the steam can be set to a desired temperature, the pressure of the steam generated by the boiler 3 can also be stabilized at a desired pressure.
　Further, in the present embodiment, since the temperature and pressure of the steam generated by the boiler 3 can be set to a desired temperature and pressure, the amount of power generated by the generator 8 can be set to the desired amount of power generation. Further, since the amount of power generated by the generator 8 can be kept constant, the power can be stably supplied. That is, even if the amount of solar radiation changes, the electric power output from the power plant 100 can be stably supplied with a desired amount of electric power.
[0068]
　Further, in the present embodiment, the temperature of the steam generated in the boiler 3 is adjusted by adjusting the amount of spray water supplied to the final overheat reducer 35 and the amount of fuel supplied to the boiler 3. There is. That is, the boiler 3 is provided with adjusting means for adjusting the temperature of the steam generated by the boiler 3. In other words, the solar heat utilization heating unit 5 is not provided with an adjusting means for adjusting the temperature of the heat medium, and the circulation flow rate of the heat medium may be a predetermined constant flow rate. As a result, the solar heat utilization heating unit 5 does not have a configuration for adjusting the temperature of the heat medium by heating the heat medium with the energy generated by condensing sunlight. Therefore, almost all of the heat obtained from sunlight can be used to heat the water supply supplied to the boiler 3. In this way, even if the amount of solar radiation changes, almost all of the heat obtained by heating the heat medium from the energy generated by condensing the sunlight can be used for heating the water supply. Therefore, the amount of heat transferred to the water supply supplied to the boiler 3 is increased as compared with the configuration in which the temperature is adjusted, such as the configuration in which the device for positively reducing the heat obtained from sunlight is provided. Therefore, the temperature of the water supply can be raised. Therefore, the fuel used to heat the water supply in the boiler 3 can be reduced.
　It should be noted that the configuration in which the temperature is adjusted, such as the configuration in which a device for positively reducing the heat obtained from sunlight is provided, is, for example, obtained from sunlight when the amount of solar radiation changes. Examples thereof include a configuration in which the energy is positively reduced to maintain the temperature of the heat medium after heating, and the heat obtained from sunlight is positively reduced. Further, for example, there is a configuration in which an adjusting means for adjusting the temperature of the heat medium by changing the circulation flow rate of the heat medium is provided, and a configuration in which an adjusting means for adjusting the amount of water supplied for heat exchange with the heat medium is provided.
[0069]
　In the present embodiment, the fuel supply amount is controlled in advance based on the temperature Th of the water supply immediately before being supplied to the economizer 38. The economizer 38 is provided on the upstream side in the above flow with respect to the final superheater 36 and the upstream superheater 34. That is, the economizer 38 is provided at a position closer to the solar heat-utilizing feed water heater 52 than the final superheater 36 and the upstream superheater 34. As a result, when the amount of solar radiation changes, the temperature of the water supplied to the economizer 38 changes faster than the water supply or steam supplied to the heat exchanger provided on the downstream side. Therefore, by controlling the fuel supply amount in advance based on the temperature Th of the water supply immediately before being supplied to the economizer 38, it is possible to respond to the change in the solar radiation amount more quickly. Therefore, by adjusting both the amount of spray water supplied to the final overheat reducer 35 and the amount of fuel supplied to the boiler 3, the fuel is prepared before the temperature of the steam generated by the boiler 3 is adjusted. The supply amount can be controlled in advance. Therefore, more accurately and quickly, the time delay to settling due to the time constant of the overall control system is suppressed, and the fuel supply amount is controlled so that the steam temperature Tm generated by the boiler 3 becomes a desired temperature. Can be done.
[0070]
　The advance control of the fuel supply amount may be performed based on the temperature Tо of the heat medium supplied from the solar heat collector 51 to the solar heat feed water heater 52.
　When the amount of solar radiation changes, the amount of heat of the heat medium in the solar heat collector 51 changes. Therefore, the heat medium temperature Tо supplied from the solar heat collector 51 to the feed water heater 52 utilizing solar heat also changes. Therefore, the heat medium temperature To changes rapidly with respect to the change in the amount of solar radiation. Therefore, by controlling the fuel supply amount in advance based on the heat medium temperature Tо, it is possible to respond to the change in the amount of solar radiation more quickly. Therefore, since it is possible to give more time margin to the setting by the time constant of the entire control system, the steam temperature Tm generated by the boiler 3 is more accurately set to the desired temperature by suppressing the time delay to the setting. The fuel supply amount can be controlled so as to be.
[0071]
　In the present embodiment, when the water supply temperature Th is lower than the first predetermined value or when the heat medium temperature Tо is lower than the second predetermined value, the first water supply on-off valve is prevented from flowing into the bypass pipe 43. It controls 23a and the second water supply on-off valve 43a. That is, when the feed water temperature Th or the heat medium temperature Tо is lower than a predetermined value, the feed water heater 52 using solar heat is not supplied with water. As a result, it is possible to prevent the feed water from being supplied to the feed water heater 52 using solar heat when the feed water cannot be suitably heated by the heat medium. Therefore, the solar heat utilization feed water heater 52 can suppress the cooling of the feed water by the heat medium. Even if the water supply does not flow into the bypass pipe 43, the water supply heaters 40, 41, and 42 can heat the water supply and control the temperature of the steam output by the boiler 3, so that the boiler can be controlled. The operation of 3 can be continued.
[0072]
　Further, in the present embodiment, as a heat medium that circulates in the solar heat utilization unit, for example, an oil-based heat medium is used as a heat medium that maintains the liquid phase even when the temperature rises and does not easily change the phase. As a result, the circulating pressurization of the heat medium can be lowered, so that the pressure resistance requirement of the heat collecting tube of the solar heat collector 51 and the like is lowered, so that the manufacturing cost of the solar heat collector 51 and the like can be suppressed.
[0073]
[Second Embodiment]
　Next, the second embodiment according to the present embodiment will be described with reference to FIG.
　The power plant 200 according to the second embodiment is different from the first embodiment in the position where the bypass pipe is provided. Therefore, the same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.
[0074]
　The bypass pipe (second bypass flow path) 82 of the boiler system 81 according to the present embodiment has an upstream end connected to a second water supply pipe 21 between the water supply pump 21a and the medium pressure water supply heater 41. That is, the bypass pipe 82 is provided so as to bypass the medium pressure water supply heater (second heat exchange section) 41 and the high pressure water supply heater (second heat exchange section) 42 from the wake side of the water supply pump 21a.
[0075]
　Further, in the present embodiment, the first water supply on-off valve 83 is provided between the branch portion of the bypass pipe 82 and the medium pressure water supply heater 41. The first water supply on-off valve 83 is an on-off valve. Further, the bypass pipe 82 is provided with a second water supply on-off valve 43a which is an on-off valve and a third water supply flow rate adjusting valve 84 which is a flow rate adjusting valve. The third water supply flow rate adjusting valve 84 is provided on the downstream side of the second water supply on-off valve 43a. Further, the third water supply flow rate adjusting valve 84 can adjust the flow rate of the water supply flowing inside the bypass pipe 82 by adjusting the opening degree.
　The opening degree of the third water supply flow rate adjusting valve 84 is set so that the amount of water supplied to the bypass pipe 82 is, for example, about 10% to 50% in the present embodiment with respect to the total flow rate of water supply. There is. That is, in the present embodiment, the medium-pressure feed water heater 41, the high-pressure feed water heater 42, and the solar heat-utilizing feed water heater 52 are provided in parallel, and both of them heat the feed water.
[0076]
　According to this embodiment, the following effects are exhibited.
　In the present embodiment, the medium-pressure feed water heater 41, the high-pressure feed water heater 42, and the solar heat-utilizing feed water heater 52 are provided in parallel, and both of them heat the feed water. As a result, the amount of water supplied by the medium-pressure water supply heater 41 and the high-pressure water supply heater 42 can be reduced, so that the amount of steam extracted through the second bleeding pipe 26 of the medium-pressure steam turbine 71 and the high-pressure steam turbine 70 The amount of steam extracted through the third bleeding pipe 27 can be reduced. Therefore, the energy obtained by the steam turbine 7 can be increased, the amount of steam supplied to the steam turbine 7 can be reduced, and the fuel used for heating the water supply in the boiler 3 can be reduced.
[0077]
[Third Embodiment]
　Next, the third embodiment according to the present invention will be described with reference to FIG.
　In the power plant 300 according to the third embodiment, the configuration of the solar heat utilization heating unit is different from that of the first embodiment. Therefore, the same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.
[0078]
　The solar heat utilization heating unit 91 according to the present embodiment uses water as a heat medium. In addition to the solar heat collector 51 and the solar heat feed water heater 52, the solar heat utilization heating unit 91 includes an air-water separator 92 provided between the solar heat collector 51 and the solar heat feed water heater 52. The condenser 93 provided between the solar heat-utilizing feed water heater 52 and the heat medium pump 53 (hereinafter referred to as "first heat medium pump 53"), the air-water separator 92, and the circulation flow path 50 are connected. It is provided with a water pipe 94. A second heat medium pump 95 is provided in the water pipe 94.
　The gas-water separator 92 separates the heat medium heated by the solar heat collector 51 into a gas-liquid two-phase into water and steam. Further, the separated steam is supplied to the feed water heater 52 utilizing solar heat via the circulation flow path 50. Further, the separated water is supplied to the circulation flow path 50 between the first heat medium pump 53 and the solar heat collector 51 via the water pipe 94. The condenser 93 condenses the heat medium (steam) obtained by heating the feed water with the solar heat-utilizing feed water heater 52 into water.
[0079]
　According to this embodiment, the following effects are exhibited.
　In this embodiment, inexpensive water or steam is used as the heat medium. Therefore, the cost of the heat medium can be reduced. Further, a steam separator 92 is provided, and only steam is supplied from the steam separator 92 to the feed water heater 52 using solar heat. As a result, the feed water heater 52 using solar heat can heat the feed water only with high-temperature steam, so that the feed water supplied from the bypass pipe 43 can be preferably heated.
[0080]
　The present invention is not limited to the invention according to each of the above embodiments, and can be appropriately modified as long as the gist of the present invention is not deviated.
　For example, in each of the above embodiments, the fuel supply amount is controlled in advance based on the temperature change of the temperature Th of the water supply immediately before being supplied to the economizer 38, but the present invention is not limited to this. For example, the fuel supply amount may be controlled in advance based on the temperature change of the temperature Te of the supply water discharged from the economizer 38.
Code description
[0081]
1: Boiler system
2: Power generation unit
3: Boiler
4: Water supply preheating unit (second heat exchange unit)
5: Solar heat utilization heating unit
7: Steam turbine
8: Generator
11: First steam pipe
11a: First steam temperature measurement Vessel
12: 2nd steam pipe
13: 3rd steam pipe
13a: 3rd steam temperature measuring instrument
13b: Steam pressure measuring instrument
13c: Steam flow rate adjusting valve
14: 4th steam pipe
15: 5th steam pipe
16: 6th steam Pipe
17: 7th steam pipe
20: 1st water supply pipe
20a: Recovery pump
21: 2nd water supply pipe
21a: Water supply pump
22: 3rd water supply pipe
23: 4th water supply pipe (water supply flow path)
23a: 1st water supply On-off valve (switching means)
23b: First water supply temperature measuring instrument (water supply thermometer side means)
24: 5th water supply pipe
24a: 2nd water supply temperature measuring instrument
25: 1st air extraction pipe
26: 2nd air extraction pipe
27: 3rd air extraction pipe
30: Fire furnace
31: Burner
32: Smoke path
33: Fuel pipe (fuel supply path) )
33a: Fuel flow control valve (fuel adjustment means)
34: Upstream superheater (upstream superheater)
35: Final superheater (superheater)
36: Final superheater (downstream superheater)
37: Reheater
38 : Coal saving device (water supply heater)
39: Spray water piping (spray water supply flow path)
39a: Spray water amount adjusting valve (spray water adjusting means)
40: Low pressure water supply heater
41: Medium pressure water supply heater
42: High pressure water supply heater
43 : Bypass piping (first bypass flow path)
43a: Second water supply on-off valve (switching means)
50: Circulation flow path
51: Solar heat collector (solar heat heating section)
52: Solar heat-utilizing feed water heater (first heat exchange unit)
53: Heat medium pump
54: Heat medium temperature measuring device (heat medium temperature measuring means)
70: High-pressure steam turbine (steam turbine)
71: Medium- pressure steam turbine
72: Low-pressure steam turbine
73: Condenser
74: Rotating shaft
81: Boiler system
82: Bypass piping (second bypass flow path)
83: First feed water on-off valve
84: Third feed water flow control valve
91: Solar heat utilization heating unit
92: Steam separator
93: Condenser
94: Water pipe
95: Second heat medium pump
100: Power plant
200: Power plant
300: Power plant
The scope of the claims
[Claim 1]
　A boiler that generates steam from
　water supply, a water supply flow path through which the water supply supplied to the boiler flows, a
　solar heat heating unit that heats a heat medium by using heat generated by condensing sunlight, and the
　above. A first, which is provided with a solar heat heating unit,
　exchanges heat between a circulation flow path that circulates the heat medium at a predetermined constant flow rate, the water supply that flows through the water supply flow path, and the heat medium that flows through the circulation flow path. 1 A
　boiler system including a heat exchange unit and adjusting means provided in the boiler to adjust the temperature of the steam generated by the boiler.
[Claim 2]
　In the circulation flow path, all of the heat medium heated by the solar heat heating unit is supplied to the first heat exchange unit, and all of the heat media exchanged by the first heat exchange unit are all of the solar heat exchange unit. The boiler system according to claim 1, which is supplied to.
[Claim 3]
　The boiler is provided between a downstream superheater that superheats the steam, an upstream superheater that is provided on the upstream side of the downstream superheater and superheats the steam, and between the downstream superheater and the upstream superheater. A superheat reducer that reduces the temperature of the steam supplied, a spray water supply flow path that extracts the water supply on the upstream side of the upstream superheater and supplies it to the superheater, and supplies fuel to the burner. The
　spray water supply flow path is provided with a spray water adjusting means for adjusting the amount of the water supplied to the superheater, and the
　fuel supply path is provided with the burner.
　The boiler system according to claim 1 or 2 , wherein a fuel adjusting means for adjusting the amount of fuel to be supplied is provided, and the adjusting means includes the spray water adjusting means and the fuel adjusting means.
[Claim 4]
　The boiler includes a water supply heating unit provided upstream of the upstream superheater to heat the supplied water, and a water supply thermometer side means for measuring the temperature of the water supply supplied to the water supply heating unit. the equipped,
　boiler system of claim 3, wherein the water thermometer side means on the basis of the feedwater temperature measuring, controlling said fuel regulating means.
[Claim 5]
　The heat medium temperature measuring means for measuring the temperature of the heat medium supplied from the solar heat heating unit to the first heat exchange unit is provided, and the
　heat medium temperature measuring means measures the temperature of the heat medium. The boiler system according to claim 3 or 4, which controls the fuel adjusting means.
[Claim 6]
　A first bypass flow path that bypasses from the
　water supply flow path, a switching means for switching whether the water supply flows through the water supply flow path or the first bypass flow path, and
　the first heat from the solar heat heating unit. A heat medium temperature measuring means for measuring the temperature of the heat medium supplied to the exchange unit is provided, and
　the first heat exchange part is provided in the first bypass flow path and
　is measured by the heat medium temperature measuring means. The method according to any one of claims 1 to 5, which controls the switching means so that the water supply does not flow into the first bypass flow path when the temperature of the heat medium is lower than a predetermined value. Boiler system.
[Claim 7]

　Bypasses a second heat exchange unit 　provided in the water supply flow path and exchanging heat between the steam extracted from the steam turbine generated by the boiler and the water supply, and the second heat exchange unit. 1. A second bypass flow path provided with the first heat exchange unit is provided, and
　a part of the water supply supplied to the boiler flows through the second bypass flow path. The boiler system according to any one of claims 5.
[Claim 8]
　A
　steam separator provided between the solar heating unit and the first heat exchange unit is provided, the heat medium is water or steam,
　and the steam separator is the supplied water and steam. The boiler system according to any one of claims 1 to 7, wherein the separated steam is supplied to the first heat exchange unit.
[Claim 9]

　A power plant comprising 　the boiler system according to any one of claims 1 to 8 and a power generation unit that generates electricity from the steam generated by the boiler.
[Claim 10]
　In a boiler,
　heat that circulates in a circulation flow path at a predetermined constant flow rate by utilizing the steam generation process that generates steam from the water supply supplied through the water supply flow path and the heat generated by condensing sunlight. By a heat medium heating step of heating the medium,
　a heat exchange step of heat exchange between the water supply flowing through the water supply flow path and the heat medium flowing through the circulation flow path, and
　an adjusting means provided in the boiler. , A method of operating a boiler system, comprising an adjusting step of adjusting the temperature of the steam generated by the boiler.