JP7330690B2 - Boiler system, power plant, and method of operating boiler system - Google Patents

Description

The present invention relates to a boiler system, a power plant, and a method of operating the boiler system.

The heat medium is heated using the concentrated heat of sunlight, which is natural energy, and the heated heat medium is effectively used to heat the boiler feed water of the thermal power plant, thereby reducing the boiler fuel supplied to the thermal power plant, Power plants that reduce carbon dioxide emissions are known.

In such power plants, the concentrated heat of sunlight is used, so when the amount of solar radiation changes, the amount of heating of the boiler feed water also changes, and the temperature of the feed water supplied to the boiler also changes. There is a problem of stowing. When the temperature of the feed water supplied to the boiler changes, the temperature of the steam supplied from the boiler to the steam turbine also changes. For this reason, power plants have been considered that take measures so that the temperature of the feed water supplied to the boiler does not change even if the amount of solar radiation changes (for example, Patent Documents 1 and 2).

In the plant described in Patent Document 1, a temperature measuring instrument for measuring the temperature of water discharged from a solar feed water heater is provided, and based on the temperature of the water measured by the temperature measuring instrument, the solar thermal feed water is It controls the flow rate of water entering the inlet of the heater.

In the plant described in Patent Document 2, a solar heater is provided in which heat is exchanged between a heat medium heated by sunlight in a heat collector and incoming feed water. In addition, by adjusting the output of the pump for circulating the heat medium, the flow rate of the heat medium is adjusted, and the temperature of the feed water flowing into the boiler is adjusted.

Japanese Patent No. 5723220 Japanese Patent No. 6178169

However, as in the plant of Patent Document 1, by controlling the flow rate of the feed water flowing into the inlet of the feed water heater using solar heat, when control is performed to keep the temperature of the feed water to the boiler constant, the feed water and the heat The temperature of the heat medium to be exchanged fluctuates. Therefore, there is a possibility that the efficiency of solar heat absorption by the heat medium that flows through the collector fluctuates, resulting in a reduction in the utilization efficiency of solar energy. Therefore, in order to supply the steam generated in the boiler to a steam turbine or the like to obtain a predetermined power output, it is necessary to increase the amount of fuel used in the boiler to compensate for the decrease in the utilization efficiency of solar energy. Therefore, the running cost may increase.

In addition, as in the plant of Patent Document 2, even when the temperature of the feed water flowing into the boiler is adjusted by adjusting the flow rate of the heat medium heated by sunlight, the solar energy that can be used depends on the amount of the heat medium. Since it changes, there is a possibility that the utilization efficiency of solar energy will be lowered. For this reason, as in 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, the reduced utilization efficiency of solar energy must be used by the boiler. Since it is necessary to increase the amount of fuel, running costs may increase.

The present invention has been made in view of such circumstances, and is capable of keeping the temperature of steam generated in a boiler at a desired temperature even when the amount of solar radiation changes. An object of the present invention is to provide a 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 that can reduce the amount of fuel used to heat feedwater in the boiler.

In order to solve the above problems, the boiler system, the power plant, and the boiler system operating method of the present invention employ the following means.
A boiler system according to a first aspect of the present invention uses a boiler that generates steam from feed water, a water supply channel through which the feed water supplied to the boiler flows, and heat generated by concentrating sunlight. a solar heating unit that heats a heat medium by means of a heat source; a circulation flow path that circulates the heat medium at a predetermined constant flow rate; and a first heat exchange section that exchanges heat with the heat medium that flows through the steam, and an adjustment means that is provided in the boiler and adjusts the temperature of the steam generated in the boiler.

The amount of heat generated by condensing light in the solar heating unit changes according to changes in the amount of solar radiation. When the amount of heat generated by the solar heating unit changes, the heating amount of the heat medium in the solar heating unit also changes. Moreover, since the temperature of the circulating heat medium changes due to the change in the heating amount of the heat medium, the amount of heat exchanged between the heat medium and the feed water in the first heat exchange section also changes. Therefore, the temperature of the feed water supplied to the boiler from the feed water channel also changes. As the temperature of the feed water supplied to the boiler changes, the temperature of the steam generated by the boiler also changes. Thus, when the amount of solar radiation changes, the temperature of the steam generated by the boiler also changes accordingly.

In the above configuration, the boiler is provided with the adjusting means for adjusting the temperature of the steam generated by the boiler. Accordingly, even when the temperature of the feed water changes due to changes 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 if the amount of solar radiation changes, the temperature of the steam generated by the boiler can be kept at a desired temperature. Note that the temperature of steam generated by the boiler includes, for example, the temperature of steam supplied from the boiler to the steam turbine.

Further, in the above configuration, the boiler is provided with the 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 adjustment means for adjusting the temperature of the heat medium. As a result, in the circulation flow path, there is a structure for adjusting the temperature, such as a configuration for actively reducing the temperature of the heat medium in order to maintain the temperature of the heat medium after heating when the amount of solar radiation changes. It becomes a configuration in which there is no configuration or the like. Therefore, substantially all of the heat obtained by heating the heat medium from the energy generated by condensing the sunlight in the solar heating unit can be used for heating the feed water supplied to the boiler. In this way, almost all of the heat obtained by heating the heat medium from the energy generated by condensing the sunlight can be used to heat the feed water even if the amount of sunlight changes. Therefore, when the amount of solar radiation changes, the energy obtained from sunlight is actively reduced to maintain the temperature of the heat medium after heating. By increasing the amount of heat transfer, the temperature of the feed water can be raised. Therefore, it is possible to reduce the fuel used to heat the feed water in the boiler by suppressing the decrease in the utilization efficiency of the solar energy.
Note that the configuration in which a device or the like is provided to actively reduce the heat obtained from sunlight includes, for example, a configuration in which an adjustment means is provided to adjust the temperature of the heat medium by changing the circulation flow rate of the heat medium, or a configuration in which the temperature of the heat medium is adjusted A configuration in which an adjusting means for adjusting the amount of water to be heat-exchanged is provided may be mentioned.
Further, in the above configuration, the circulation flow rate of the heat medium is set at a predetermined constant flow rate. The predetermined constant flow rate is, for example, the temperature of the heat medium obtained by heating the heat medium from the energy generated by concentrating the sunlight in the solar heat heating section under the condition that the solar energy is the highest. It is also possible to set the flow rate at which the design temperature of

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 heating unit is supplied to the first heat exchange unit, and may be supplied to the solar heating unit.

In the above configuration, all of the heat medium heated by the solar heating section is supplied to the first heat exchange section, and all of the heat medium heat-exchanged by the first heat exchange section is supplied to the solar heating section. As a result, it is ensured that the circulation flow path does not have a structure for actively reducing the heat obtained by heating the heat medium with the energy generated by condensing the sunlight in the solar heating unit. can be done. Therefore, substantially all of the heat obtained by heating the heat medium in the solar heat heating section from the solar energy can be reliably used for heating the feed water in the first heat exchange section.

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 that is provided upstream of the downstream superheater and superheats the steam, and a desuperheater provided between the downstream superheater and the upstream superheater to reduce the temperature of the supplied steam; and a fuel supply passage for supplying fuel to the burner. Spray water adjusting means for adjusting the amount of water supplied to the desuperheater in the spray water supply passage. and the fuel supply passage is provided with fuel adjusting means for adjusting the amount of fuel supplied to the burner, and the adjusting means has the spray water adjusting means and the fuel adjusting means.

In the above configuration, the temperature of the steam generated by the boiler is adjusted by controlling the spray water adjusting means and the fuel adjusting means. As a result, even if the temperature of the feed water changes due to a change in the amount of solar radiation, the temperature of the steam generated in the boiler can be reliably adjusted within the boiler.
It is more preferable that the spray water adjustment means is controlled so that the temperature of the steam generated by the boiler reaches a desired temperature based on the temperature of the steam heated by the downstream superheater. Further, it is more preferable that the fuel adjustment means is controlled based on the temperature of the steam supplied to the desuperheater so that the temperature of the steam generated by the boiler reaches a desired temperature.

Further, in the boiler system according to the first aspect of the present invention, the boiler includes a feed water heating unit that is provided upstream of the upstream superheater and heats the supplied feed water, and the feed water heating unit. a feedwater thermometer side means for measuring the temperature of the feedwater, and the fuel adjustment means may be controlled based on the temperature of the feedwater measured by the feedwater thermometer side means.

In the above configuration, the feedwater thermometer side means for measuring the temperature of the feedwater supplied to the feedwater heating section is provided, and the fuel adjustment means is controlled based on the temperature of the feedwater measured by the feedwater thermometer side means. The feed water heating unit is provided upstream of the downstream superheater, the upstream superheater, and the like. That is, the feed water heating section is provided at a position closer to the first heat exchange section than the downstream superheater, the upstream superheater, and the like. As a result, the temperature of the water supplied to the water heating unit changes more quickly than the configuration provided downstream, such as the upstream superheater 34, when the amount of solar radiation changes. Therefore, by controlling the fuel adjustment means based on the temperature of the water supply supplied to the water supply heating unit, it is possible to respond more quickly to changes in the amount of solar radiation. Therefore, it is possible to more accurately control the fuel adjustment means so that the temperature of the steam generated by the boiler reaches the desired temperature.

Further, the boiler system according to the first aspect of the present invention includes 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 the heat medium temperature measurement means The fuel adjustment means may be controlled based on the temperature of the heat medium measured by the means.

In the above configuration, the 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 is provided, and based on the temperature of the heat medium measured by the heat medium temperature measuring means, the fuel controlling the regulating means. When the amount of solar radiation changes, the amount of heating of the heat medium by the heat generated by concentrating the sunlight in the solar heating unit changes. Therefore, the temperature of the heat medium supplied from the solar heating section to the first heat exchange section also changes. Therefore, the temperature of the heat medium supplied from the solar heating section to the first heat exchange section rapidly changes with changes in the amount of solar radiation. Therefore, by controlling the fuel adjustment means based on the temperature of the heat medium supplied from the solar heating section to the first heat exchange section, it is possible to respond more quickly to changes in the amount of solar radiation. Therefore, it is possible to more accurately control the fuel adjustment means so that the temperature of the steam generated by the boiler reaches the desired temperature.

Further, the boiler system according to the first aspect of the present invention includes a first bypass flow path that bypasses the water supply flow path, and whether the feed water flows through the water supply flow path or through the first bypass flow path. switching means for switching; and heat medium temperature measuring means for measuring the temperature of the heat medium supplied from the solar heating section to the first heat exchange section, wherein the first heat exchange section The switching means is provided in the first bypass flow path so that the feed water 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.

In the above configuration, when the temperature of the heat medium supplied to the first heat exchange section is lower than a predetermined value, the switching means is controlled so that feed water does not flow into the first bypass flow path. That is, when the temperature of the heat medium is lower than a predetermined value, feed water is not supplied to the first heat exchange section. Accordingly, when the temperature of the heat medium is lower than a predetermined value and the heat medium cannot suitably heat the feed water, it is possible to prevent the feed water from being supplied to the first heat exchange section. Note that the predetermined value includes, for example, the temperature of the water supply supplied to the first heat exchange section. When the temperature of the heat medium supplied to the first heat exchange section is lower than the temperature of the water supply supplied to the first heat exchange section, the water supply may be cooled by the heat medium. Therefore, cooling of the feed water can be suppressed by preventing the feed water from being supplied to the first heat exchange section in such a case.

In addition, the boiler system according to the first aspect of the present invention is provided in the water supply passage, and the second steam extracted from a steam turbine driven by the steam generated in the boiler is heat-exchanged with the water supply. a heat exchange section; and a second bypass passage provided to bypass the second heat exchange section and provided with the first heat exchange section. A portion of the supplied water supply may be circulated.

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 feed water with the steam extracted from the steam turbine. part of the water supply is distributed. That is, the feed water is heated by the first heat exchange section and the second heat exchange section provided in parallel with the first heat exchange section. As a result, the amount of water to be heated in the second heat exchange section can be reduced, so the amount of steam extracted from the steam turbine can be reduced. Therefore, the energy available in the steam turbine can be increased.

Further, the boiler system according to the first aspect of the present invention includes a steam separator provided between the solar heating unit and the first heat exchange unit, wherein the heat medium is water or steam, The steam separator may separate the supplied water and steam and supply the separated steam to the first heat exchange section.

In the above configuration, inexpensive water or steam is used as the heat medium. Therefore, the cost of the heat medium can be reduced.
Also, a steam separator is provided, and only steam is supplied from the steam separator to the first heat exchange section. As a result, in the first heat exchange section, the feed water can be heated only by high-temperature steam, so that the feed water can be suitably heated.

A power plant according to a first aspect of the present invention includes any one of the boiler systems described above and a power generation section that generates power using the steam generated by the boiler.

With 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 a desired amount. Further, when the temperature of the steam generated by the boiler is kept constant, the amount of power generated by the power generation unit can be kept constant, so that electric power can be stably supplied.

A method for operating a boiler system according to a first aspect of the present invention includes, in a boiler, a steam generating step of generating steam from feed water supplied through a feed water channel, and heat generated by concentrating sunlight. a heat medium heating step of heating the heat medium circulating in the circulation channel at a predetermined constant flow rate; and an adjusting step of adjusting the temperature of the steam generated in the boiler by adjusting means provided in the boiler.

ADVANTAGE OF THE INVENTION According to this invention, even when the amount of solar radiation of sunlight changes, the temperature of the steam produced|generated by a boiler can be made into desired temperature.
Also, the fuel used to heat the feedwater in the boiler can be reduced.

1 is a schematic configuration diagram of a power plant according to a first embodiment of the present invention; FIG. 4 is a flowchart showing processing performed by a control device provided in the power plant according to the first embodiment of the present invention; FIG. 3 is a flow chart showing the processing performed by the control device provided in the power plant according to the first embodiment of the present invention, and is a flow chart continuing from FIG. 2 ; FIG. FIG. 4 is a schematic configuration diagram of a power plant according to a second embodiment of the present invention; FIG. 7 is a schematic configuration diagram of a solar feed water heater provided in a power plant according to a third embodiment of the present invention;

An embodiment of a boiler system, a power plant, and a method of operating the boiler system according to the present invention will be described below with reference to the drawings.

[First Embodiment]
A first embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG.
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 includes a boiler 3 that generates steam from feed water, a feed water preheating unit (second heat exchange unit) 4 that heats the feed water supplied to the boiler 3 with steam extracted from a steam turbine 7 described later, and sunlight. A solar heat utilization heating unit 5 that heats feed water supplied to the boiler 3 by exchanging heat with a heating medium that is heated using energy generated by condensing light, and a control device (not shown) that controls various devices. , is equipped with
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 is generated by the rotational driving force of the steam turbine 7 .

The boiler 3 includes a furnace 30, burners 31 provided on the walls of the furnace 30, and a flue 32 through which combustion gas generated in the furnace 30 flows.
The burner 31 burns fuel supplied through a fuel pipe (fuel supply path) 33 to form a flame within the furnace 30 . The fuel pipe 33 is provided with a fuel flow rate adjusting valve (fuel adjusting means) 33a that adjusts the flow rate of the fuel that flows inside. The fuel flow control valve 33a can adjust the flow rate of the fuel supplied to the burner 31 by adjusting the degree of opening.

In the flue 32, in the example of the present embodiment, at least an upstream superheater (upstream superheater) 34, a final superheater (superheater) 35, a final superheater (Downstream superheater) 36 , reheater 37 and economizer (feed water heating unit) 38 are provided. Note that heat exchangers other than this 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 feed water (or steam) flowing therein. do.

In the feedwater or steam flow, the economizer 38 is provided most upstream among the heat exchangers provided in the boiler 3 . A downstream end of the economizer 38 is connected to an upstream end of the upstream superheater 34 via the fifth water supply pipe 24 . Water flowing through the fifth water supply pipe 24 becomes saturated steam due to heat from the furnace 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 24 a for measuring the temperature Te of water flowing through the fifth water supply pipe 24 . The second feed water temperature measuring instrument 24a transmits the measured temperature to the control device. A spray water pipe (spray water supply flow path) 39 branches off from a midway position of the fifth water supply pipe 24 . The spray water pipe 39 extracts part of the water supply flowing through the fifth water supply pipe 24 and supplies the extracted water to the final desuperheater 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 therein. The spray water amount adjustment valve 39a can adjust the amount of water supplied to the final desuperheater 35 by adjusting the degree of opening. A heat exchanger (evaporator) (not shown) may be provided in the middle of the fifth water supply pipe 24 to evaporate the water supply using heat from the furnace 30 . Further, the spray water pipe 39 may supply the extracted water to the pipe upstream of the final desuperheater 35 (that is, the first steam pipe 11).

A downstream end of the upstream superheater 34 is connected to the final desuperheater 35 via the first steam pipe 11 . The first steam pipe 11 is provided with a first steam temperature measuring instrument 11 a for measuring the temperature Ts of steam flowing through the first steam pipe 11 . The first steam temperature measuring instrument 11a transmits the measured temperature to the control device.

The final desuperheater 35 is connected to the upstream end of the final superheater 36 via the second steam line 12 . A downstream end of the final superheater 36 is connected via a third steam pipe 13 to a high-pressure steam turbine (steam turbine) 70 to be described later. The third steam pipe 13 is provided with a third steam temperature measuring instrument 13 a for measuring the temperature Tm of steam flowing through the third steam pipe 13 . Further, the third steam pipe 13 is provided with a steam pressure measuring instrument 13 b for measuring the pressure Pm of steam flowing through the third steam pipe 13 . The third steam temperature measuring instrument 13a and 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 control valve 13c downstream of the third steam temperature measuring device 13a and the steam pressure measuring device 13b. The steam flow rate adjustment valve 13c adjusts the flow rate of the steam supplied to the high-pressure steam turbine 70 through the inside thereof by adjusting the degree of opening.

The upstream end of the reheater 37 is connected to the downstream end of the high pressure steam turbine 70 via the fourth steam pipe 14 . A downstream end of the reheater 37 is connected to an intermediate pressure steam turbine 71 to be described later via a fifth steam pipe 15 .

The steam turbine 7 comprises, in this embodiment, for example, a high pressure steam turbine 70, an intermediate pressure steam turbine 71 and a low pressure steam turbine 72 which are coaxially coupled. The high-pressure steam turbine 70 , the intermediate-pressure steam turbine 71 and the low-pressure steam turbine 72 are each rotationally driven by steam supplied from the boiler 3 . A downstream end of the intermediate pressure steam turbine 71 is connected to the low pressure steam turbine 72 via the sixth steam pipe 16 . A downstream end of the low-pressure steam turbine 72 is also connected to a condenser 73 via a seventh steam pipe 17 . The condenser 73 condenses the supplied steam into condensed water.

The generator 8 is coupled to a rotating shaft 74 shared by the high pressure steam turbine 70 , intermediate pressure steam turbine 71 and low pressure steam turbine 72 . The generator 8 generates electric power by converting the rotational driving force transmitted from each steam turbine via the rotating shaft 74 into electric power.

The feedwater preheating unit 4 includes a low-pressure feedwater heater 40 that heats feedwater with steam extracted from the low-pressure steam turbine 72 , an intermediate-pressure feedwater heater 41 that heats feedwater with steam extracted from the intermediate-pressure steam turbine 71 , and the high-pressure steam turbine 70 . and a high-pressure feed water heater 42 that heats the feed water with steam bled from.

The low-pressure feed water heater 40 is arranged most upstream in the feed water flow among the three feed water heaters 40 , 41 , 42 . An 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 supplying water. The low-pressure feedwater heater 40 is also connected to the low-pressure steam turbine 72 via the first extraction pipe 25 . The low-pressure feed water heater 40 exchanges heat between feed water and steam supplied through the first extraction pipe 25 .

The low-pressure water heater 40 and the medium-pressure water heater 41 are connected via the second water supply pipe 21 . The second water supply pipe 21 is provided with a water supply pump 21a that pressurizes and circulates water. The medium pressure water heater 41 and the high pressure water heater 42 are connected via the third water supply pipe 22 . The intermediate pressure feed water heater 41 is also connected to the intermediate pressure steam turbine 71 via the second extraction pipe 26 . The medium-pressure feed water heater 41 exchanges heat between feed water and steam supplied through the second extraction pipe 26 .

A downstream end of the high pressure water supply heater 42 is connected to an upstream end of the economizer 38 via a fourth water supply pipe (water supply flow path) 23 . A first water supply opening/closing valve (switching means) 23 a is provided in the middle of the fourth water supply pipe 23 . The first water supply opening/closing valve 23a is an opening/closing valve. Further, a bypass pipe (first bypass flow path) 43 is provided from a midway position of the fourth water supply pipe 23 so as to bypass the first water supply opening/closing valve 23a. That is, the upstream end of the bypass pipe 43 is connected to the upstream side of the first water supply opening/closing valve 23 a 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 opening/closing valve 23 a of the fourth water supply pipe 23 . The bypass pipe 43 is provided with a second water supply opening/closing valve (switching means) 43a. The second water supply opening/closing valve 43a is an opening/closing valve. Further, the fourth water supply pipe 23 is provided with a first water supply temperature measuring device (water supply temperature gauge side means) 23b. The first water supply temperature measuring device 23 b is provided downstream of the connecting portion to the downstream end of the bypass pipe 43 in the fourth water supply pipe 23 . The first water supply temperature measuring instrument 23b measures the temperature Th of the water supply flowing through the fourth water supply pipe 23 downstream of the connecting 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.
The high pressure feed water heater 42 is also connected to the high pressure steam turbine 70 via the third extraction pipe 27 . The high-pressure feed water heater 42 exchanges heat between the feed water and the steam supplied through the third extraction pipe 27 .

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 ( a first heat exchange section) 52; In addition, in the circulation flow path 50, a heat medium temperature measuring instrument (heat medium temperature measuring means) 54 is provided. The heat medium temperature measuring instrument 54 transmits the measured temperature to the control device. As the heat medium circulating in the circulation flow path 50, in the present embodiment, for example, an oil-based heat medium that maintains a liquid phase even when the temperature rises and is less likely to undergo a phase change is used. Note that the heat medium is not limited to this, and may be, for example, a molten salt-based heat medium.

The solar heat collector 51 heats the heat medium using energy generated by concentrating sunlight. The solar heat collector 51 may be, for example, of a Fresnel type (a system in which a heat medium is heated by a flat or small-curved reflector) or a trough type (a system in which a heat medium is heated by a curved reflector). good. Moreover, a tower type may be used. In this embodiment, for example, a plurality of solar heat collectors 51 are provided in parallel, and three solar heat collectors 51 are illustrated. Note that the number of solar heat collectors 51 is not limited to this. It may be one or two. In addition, the number of units may be four or more.

The solar heat utilization feed water heater 52 is provided between the solar heat collector 51 and the heat medium pump 53 . The solar heat utilization feed water heater 52 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 device 54 measures the temperature To of the heat medium immediately after being heated by the solar heat collector 51 among the heat medium circulating in the circulation flow path 50 .

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 water heater 52 and circulated at a predetermined constant flow rate. All of the heat medium heat-exchanged in the solar feed water heater 52 is introduced into the heat medium pump 53 . Also, 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.

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. A series of processes for realizing various functions are stored in a storage medium or the like in the form of a program, for example, and the CPU reads out this program to a RAM or the like, and executes information processing and arithmetic processing. As a result, various functions are realized. The program may be pre-installed in a ROM or other storage medium, provided in a state stored in a computer-readable storage medium, or delivered via 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.

The controller controls the open/closed state or degree of opening of each valve. A control device controls the driving and stopping of each pump. The controller 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 reaches a predetermined temperature based on the temperature measured by each temperature measuring instrument.

Steam temperature control processing performed by the control device will be described below with reference to the flow charts of FIGS. 2 and 3. FIG.
When the steam temperature control process is started, the controller first sets the target steam temperature Tm of the steam discharged from the final superheater 36 (that is, the steam discharged from the boiler 3) and the target temperature Tm of the steam discharged from the final superheater 36. A target pressure for the 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, for example, to the temperature and pressure when the high-pressure steam turbine 70 rotates at the rated speed. Next, the control device advances to S2 to determine whether or not the temperature Th of the water supply immediately before being supplied to the economizer 38 has changed, determines whether or not the temperature To of has changed. If it is determined that either one of them has changed, the control device determines that there has been a change in the amount of insolation, and proceeds to S3. If it is determined that neither value has changed, it is determined that the amount of solar radiation has not changed, and S2 is repeated again after a predetermined period of time.

In S3, the control device determines whether or not the feed water temperature Th is lower than a first predetermined value and whether or not the heat medium temperature To is lower than a second predetermined value. If it is determined that either one of them is smaller than the predetermined value, it is determined that the amount of solar radiation is reduced and that the heat medium is not properly heating the water supply, and the process proceeds to S4. If it is determined that both are greater than the predetermined value, the control device determines that the heat medium is suitably heating the water supply, and proceeds to S7. It should be noted that the first predetermined value and the second predetermined value are, for example, heat exchange in the solar feed water heater 52, respectively, 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 it is supplied to the charcoal generator 38 and the temperature To 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 solar feed water heater 52, the first predetermined value and the second predetermined value are, for example, the temperature of the feed water immediately before heat exchange in the solar feed water heater 52. may be used.

In S4, the control device opens the first water supply opening/closing valve 23a from the closed state, and closes the second water supply opening/closing valve 43a from the open state. Next, the control device stops the heat medium pump 53 (S5). After stopping the heat medium pump 53, the control device proceeds to S6 and determines whether or not the heat medium temperature To is higher than the second predetermined value by the amount of α (second predetermined value+α) or higher. If it is determined to be equal to or greater than the second predetermined value +α, it is determined that the amount of solar radiation has increased and the amount of solar radiation has reached a value that allows the heat medium to suitably heat the water supply. Then, first, the heat medium pump 53 is started. Next, the second water supply opening/closing valve 43a is changed from the closed state to the open state, and the first water supply opening/closing valve 23a is changed from the open state to the closed state. Then, the process proceeds to S7. If it is determined in S6 that the amount is smaller than the second predetermined value +α, it is determined that the amount of solar radiation is not sufficient to suitably heat the water supply using the heat medium, and S6 is repeated after a predetermined period of time. By setting the temperature at which the heating of the water supply by the heat medium is resumed to be higher than the second predetermined value by the amount of α, hysteresis can be provided and chattering can be suppressed. For example, a suitable value between 0.5 and 10°C may be used for α.

Proceeding to S7, the control device calculates an estimated amount of the flow rate of the fuel to be supplied to the boiler 3 based on the feed water temperature Th. Next, in S8, the flow rate of the fuel supplied to the burner 31 is adjusted by controlling the opening degree of the fuel flow rate adjusting valve 33a so that the fuel flow rate estimated in S7 is achieved as the preceding control. The estimated amount of the flow rate of the fuel supplied 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 section 2) and the feed water temperature Th. Since the degree of opening of the fuel flow rate adjusting valve 33a is also controlled in S10, which will be described later, the control of the degree of opening of the fuel flow rate adjusting valve 33a performed in S8 is prior control to the control in S10.

After the preceding control of the fuel flow rate adjustment valve 33a is finished, the control device executes a process of controlling the temperature of the steam 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 desuperheater 35. FIG. Specifically, in S9, the control device controls the opening degree of the spray water amount adjustment valve 39a so that the steam temperature Tm becomes the target temperature.
Next, the control device advances to S10, controls the opening degree of the fuel flow control valve 33a, and adjusts the flow rate of the fuel supplied to the burner 31. FIG. Specifically, in S10, the control device controls the opening degree of the fuel flow control valve 33a so that the steam temperature Ts immediately before the final desuperheater 35 reaches a predetermined temperature.

Next, the control device proceeds to S11 and determines whether the steam temperature Tm output from the boiler 3 is the target steam temperature. When 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 feed water temperature Th is lower than a third predetermined value. The third predetermined value is set, for example, to the value of the temperature at which feedwater evaporates within the economizer 38 . If it is determined that the temperature Th is equal to or higher than the third predetermined value, it is determined that the feed water is vaporized in the economizer 38, and the process returns to S3. It is determined again whether the temperature To is smaller than the second predetermined value and the necessary steps are performed. If it is determined that it 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, it is possible to keep the opening of the steam flow control valve 13c unchanged. After maintaining the opening degree of the steam flow rate control valve 13c, the control device ends this process.

Next, the flow of water and steam in this embodiment will be described.
The feed water discharged from the condenser 73 is supplied to the condensate pump 20a. The feed water discharged from the condensate pump 20 a is first introduced into the low-pressure feed water heater 40 . In the low-pressure feedwater heater 40, feedwater is heated by heat exchange between feedwater introduced through the first feedwater pipe 20 and steam introduced from the low-pressure turbine through the first extraction pipe 25. The water 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 increase the pressure. The water discharged from the water supply pump 21 a is introduced into the intermediate pressure water supply heater 41 . In the intermediate-pressure feedwater heater 41, the feedwater is heated by heat exchange between the feedwater introduced through the second feedwater pipe 21 and the steam introduced from the intermediate-pressure turbine through the second extraction pipe 26. . The water 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 feed water heater 42, the feed water is heated by heat exchange between the feed water introduced through the third feed pipe 22 and the steam introduced from the high pressure turbine through the third extraction pipe 27. The water 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 temperature of the water supply flowing through the fourth water supply pipe 23 is raised to approximately 290 to 300° C. (the temperature is an example in the present embodiment and is not limited to this).

When the first water supply opening/closing valve 23a is open and the second water supply opening/closing valve 43a is closed, the water flowing through the fourth water supply pipe 23 is directly sent to the economizer 38 provided in the boiler 3. supplied. On the other hand, when the first water supply opening/closing valve 23a is closed and the second water supply opening/closing valve 43a is open, the entire flow of water flowing through the fourth water supply pipe 23 flows into the bypass pipe 43. The feed water flowing through the bypass pipe 43 is introduced into the solar feed water heater 52 . In the solar heat-utilizing feed water heater 52, 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 heated by the solar water heater 52 is discharged from the solar water heater 52 and flows into the fourth water supply pipe 23 again through the bypass pipe 43 . The feed water that has flowed into the fourth pipe is supplied to the economizer 38 provided in the boiler 3 . At this time, the feed water temperature Th is raised to approximately 300 to 310° C. (the temperature is an example in the present embodiment and is not limited to this).

The feed water supplied to the economizer 38 exchanges heat with the combustion gas in the boiler 3 in the economizer 38 and is heated. The feed water heated by the economizer 38 is discharged from the economizer 38 and supplied to the upstream superheater 34 via the fifth feed water pipe 24 . The water flowing through the fifth water supply pipe 24 becomes saturated steam due to the heat from the furnace 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 introduced through the fifth water supply pipe 24 exchanges heat with the combustion gas, thereby superheating the steam. The steam superheated by the upstream superheater 34 is discharged from the upstream superheater 34 and introduced into the final desuperheater 35 . The final desuperheater 35 adjusts the temperature of the steam by spraying the spray water extracted from the fifth water supply pipe 24 onto the steam. The steam discharged from the final desuperheater 35 is introduced into the final superheater 36 via the second steam pipe 12 . In the final superheater 36, the steam introduced through the second steam pipe 12 exchanges heat with the combustion gas, thereby superheating the steam. The steam superheated by the final superheater 36 is discharged from the final superheater 36 and output from the boiler 3 (steam generation step).

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 . 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 introduced through the fourth steam pipe 14 exchanges heat with the combustion gas to heat the steam. The steam heated by the reheater 37 is discharged from the reheater 37 and output again from the boiler 3 .

Steam output from the reheater 37 is supplied to the intermediate pressure steam turbine 71 via the fifth steam pipe 15 . The steam supplied to the intermediate pressure steam turbine 71 rotates the intermediate pressure steam turbine 71 and is discharged from the intermediate pressure steam turbine 71 . Steam discharged from the intermediate 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 . 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 cooled and condensed. The condensed steam (that is, water) becomes feed water and is introduced into the condensate pump 20a.

Next, the flow of the heat medium in this embodiment will be described.
The heat medium discharged from the heat medium pump 53 flows 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 concentrating the 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 utilization feed water heater 52 . In the solar heat-utilizing feed water heater 52, heat is exchanged between the heat medium and the feed water (heat exchange step). At this time, the heat medium temperature To is raised to approximately 320 to 350° C. (the temperature is an example in the present embodiment and is not limited to this). The heat medium discharged from the solar water heater 52 is supplied to the heat medium pump 53 .

According to this embodiment, the following effects are obtained.

The amount of energy generated by collecting light with the solar heat collector 51 changes according to changes in the amount of solar radiation. When the amount of energy generated by the solar heat collector 51 changes, the heating amount of the heat medium in the solar heat collector 51 also changes. Moreover, since the temperature of the circulating heat medium changes due to the change in the heating amount of the heat medium, the amount of heat exchanged between the heat medium and the water supply in the solar water heater 52 also changes. Therefore, the temperature of the water supplied to the boiler 3 from the fourth water supply pipe 23 also changes. In a conventional boiler, the temperature of the steam generated by the boiler 3 changes as the temperature of the feed 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.

In this embodiment, the control device adjusts both the amount of spray water supplied to the final desuperheater 35 and the amount of fuel supplied to the boiler 3, so that the temperature of the steam generated in the boiler 3 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 desuperheater 35, and is controlled with little time delay and excellent responsiveness. When the amount of spray water increases, the flow rate of steam introduced into the upstream superheater 34 decreases and the steam temperature at the inlet of the final desuperheater 35 also fluctuates. Quantitative adjustments provide an inherent heat balance in the boiler 3, and the steam temperature produced can be implemented with controlled long-term balance fluctuations.
As a result, even when the temperature of the feed water supplied to the boiler 3 changes due to a change in the amount of solar radiation, the temperature of the steam generated in the boiler 3 is quickly brought to the desired temperature, and the steam is discharged from the boiler 3. can be output. Moreover, since the temperature of the steam can be set to the desired temperature, the pressure of the steam generated in the boiler 3 can also be stabilized at the desired pressure.
In addition, in this embodiment, the temperature and pressure of the steam generated by the boiler 3 can be set to the desired temperature and pressure, so the power generation amount generated by the generator 8 can be set to the desired power generation amount. In addition, since the amount of power generated by the generator 8 can be kept constant, power can be stably supplied. That is, even if the amount of solar radiation changes, the power output from the power plant 100 can be stably supplied at a desired amount.

Further, in this embodiment, the temperature of the steam generated in the boiler 3 is adjusted by adjusting the amount of spray water supplied to the final desuperheater 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 is configured to heat the heat medium with the energy generated by condensing the sunlight and to actively reduce the temperature of the heat medium. Therefore, substantially all of the heat obtained from sunlight can be used for heating the feed water supplied to the boiler 3 . In this way, almost all of the heat obtained by heating the heat medium from the energy generated by condensing the sunlight can be used to heat the feed water even if the amount of sunlight changes. For this reason, the amount of heat transferred to the feed water supplied to the boiler 3 is increased compared to a configuration in which a configuration for adjusting the temperature is provided, such as a configuration in which a device for actively reducing the heat obtained from sunlight is provided. can increase the temperature of the feed water. Therefore, the fuel used for heating the feed water in the boiler 3 can be reduced.
Note that the configuration in which a configuration for adjusting the temperature, such as a configuration in which a device is provided to actively reduce the heat obtained from sunlight, for example, is a configuration in which heat obtained from sunlight changes when the amount of solar radiation changes. Examples include a configuration for actively reducing the heat obtained from the sunlight by providing a configuration for actively reducing the energy to maintain the temperature of the heat medium after heating. Further, for example, there is a configuration in which adjusting means is provided to adjust the temperature of the heat medium by changing the circulation flow rate of the heat medium, and a configuration in which an adjusting means is provided to adjust the amount of water supply for heat exchange with the heat medium.

In this embodiment, the fuel supply amount is preliminarily controlled based on the temperature Th of the water supply just before it is supplied to the economizer 38 . The economizer 38 is provided upstream of the final superheater 36 and the upstream superheater 34 in the flow. That is, the economizer 38 is provided closer to the solar feed water heater 52 than the final superheater 36 and the upstream superheater 34 . As a result, the temperature of the water supplied to the economizer 38 changes faster than the water and steam supplied to the heat exchanger provided downstream when the amount of solar radiation changes. Therefore, by pre-controlling the fuel supply amount based on the temperature Th of the water supply immediately before being supplied to the economizer 38, it is possible to respond more quickly to changes in the amount of solar radiation. Therefore, by adjusting both the amount of spray water supplied to the final desuperheater 35 and the amount of fuel supplied to the boiler 3, it is possible to reduce the amount of fuel before adjusting the temperature of the steam generated by the boiler 3. The feed rate can be pre-controlled. Therefore, it is possible to more accurately and quickly control the amount of fuel supply so that the steam temperature Tm generated in the boiler 3 reaches a desired temperature by suppressing the time delay to settling due to the time constant of the overall control system. can be done.

The preliminary control of the fuel supply amount may be performed based on the temperature To of the heat medium supplied from the solar heat collector 51 to the solar water heater 52 .
When the amount of solar radiation changes, the heating amount of the heat medium in the solar heat collector 51 changes. Therefore, the heat medium temperature To supplied from the solar heat collector 51 to the solar water heater 52 also changes. Therefore, the heat medium temperature To changes quickly with changes in the amount of solar radiation. Therefore, by preliminarily controlling the amount of fuel supply based on the heat medium temperature To, it is possible to more quickly respond to changes in the amount of solar radiation. Therefore, it is possible to provide a further time margin for settling by the time constant of the overall control system, so that the time delay to settling can be suppressed and the steam temperature Tm generated in the boiler 3 can be more accurately adjusted to the desired temperature. The amount of fuel supplied can be controlled so that

In this embodiment, when the feed water temperature Th is lower than the first predetermined value, or when the heat medium temperature To is lower than the second predetermined value, the first feed water opening/closing valve is operated so that the feed water does not flow into the bypass pipe 43. 23a and the second water supply opening/closing valve 43a. That is, when the feed water temperature Th or the heat medium temperature To is lower than a predetermined value, feed water is not supplied to the solar feed water heater 52 . Accordingly, when the heat medium cannot suitably heat the water, the water is not supplied to the solar water heater 52 . Therefore, it is possible to suppress the cooling of the water supply by the heating medium in the solar water supply heater 52 . Even if the feed water is prevented from flowing into the bypass pipe 43, the feed water heaters 40, 41, and 42 can heat the feed water and control the temperature of the steam output from the boiler 3. 3 operation can be continued.

In addition, in the present embodiment, as the heat medium circulating in the solar heat utilization unit, for example, an oil-based heat medium is used as a heat medium that maintains a liquid phase and does not undergo a phase change even when the temperature rises. As a result, the circulating pressurization of the heat medium can be reduced, so that the pressure resistance required for the heat collection pipes of the solar heat collector 51 can be reduced, so that the manufacturing cost of the solar heat collector 51 and the like can be suppressed.

[Second embodiment]
Next, a second embodiment according to this 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 of providing the bypass pipe. Therefore, configurations similar to those of the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof are omitted.

A bypass pipe (second bypass flow path) 82 of the boiler system 81 according to the present embodiment is connected at its upstream end to the second feed water pipe 21 between the feed water pump 21 a and the intermediate pressure feed water heater 41 . That is, the bypass pipe 82 is provided so as to bypass the intermediate pressure water heater (second heat exchange section) 41 and the high pressure water heater (second heat exchange section) 42 from the downstream side of the water supply pump 21a.

Further, in this embodiment, the first water supply opening/closing valve 83 is provided between the branched portion of the bypass pipe 82 and the intermediate pressure water supply heater 41 . Also, the first water supply opening/closing valve 83 is an opening/closing valve. In addition, the bypass pipe 82 is provided with a second water supply opening/closing valve 43a as an opening/closing valve and a third water supply flow rate adjustment valve 84 as a flow rate adjustment valve. The third water supply flow control valve 84 is provided downstream of the second water supply opening/closing valve 43a. Further, the third water supply flow rate adjustment valve 84 can adjust the flow rate of water supply flowing through the inside of the bypass pipe 82 by adjusting the degree of opening.
The degree of opening of the third water supply flow rate adjusting valve 84 is set so that the amount of water flowing into the bypass pipe 82 is, for example, about 10% to 50% of the total water supply flow rate in this embodiment. there is That is, in this embodiment, the medium-pressure water heater 41, the high-pressure water heater 42, and the solar water heater 52 are provided in parallel, and both of them heat the water.

According to this embodiment, the following effects are obtained.
In this embodiment, a medium-pressure water heater 41, a high-pressure water heater 42, and a solar water heater 52 are provided in parallel, and both heat water. As a result, the amount of water to be heated by the medium-pressure feedwater heater 41 and the high-pressure feedwater heater 42 can be reduced. The amount of steam extracted through the third extraction 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 decreased, and the fuel used to heat the feedwater in the boiler 3 can be reduced.

[Third Embodiment]
Next, a third embodiment according to the present invention will be described with reference to FIG.
A power plant 300 according to the third embodiment differs from the first embodiment in the configuration of the solar heat utilization heating unit. Therefore, configurations similar to those of the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof are omitted.

The solar heating unit 91 according to this embodiment uses water as a heat medium. In addition to the solar heat collector 51 and the solar feed water heater 52, the solar heat utilization heating unit 91 includes a steam separator 92 provided between the solar heat collector 51 and the solar heat feed water heater 52, A condenser 93 provided between a solar feed water heater 52 and a heat medium pump 53 (hereinafter referred to as a "first heat medium pump 53"), a steam separator 92, and a circulation flow path 50 are connected. a water pipe 94; A second heat medium pump 95 is provided in the water pipe 94 .
The steam-water separator 92 separates the heat medium, which has been heated by the solar heat collector 51 and turned into a gas-liquid two-phase, into water and steam. Also, the separated steam is supplied to the solar water heater 52 through the circulation flow path 50 . Also, 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) heated by the solar water heater 52 into water.

According to this embodiment, the following effects are obtained.
In this embodiment, inexpensive water or steam is used as the heat medium. Therefore, the cost of the heat medium can be reduced. Also, a steam separator 92 is provided, and only steam is supplied from the steam separator 92 to the solar water heater 52 . As a result, the solar water supply heater 52 can heat the water only with high-temperature steam, so that the water supplied from the bypass pipe 43 can be suitably heated.

It should be noted that the present invention is not limited to the inventions according to the above embodiments, and can be modified as appropriate without departing from the scope of the invention.
For example, in each of the embodiments described above, the fuel supply amount is preliminarily controlled based on the change in the temperature Th of the feed water 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 preliminarily controlled based on the temperature change of the temperature Te of the feed water discharged from the economizer 38 .

1: Boiler system 2: Power generation unit 3: Boiler 4: Feed water 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 measuring device 12: Second steam pipe 13: Third steam pipe 13a: Third steam temperature measuring device 13b: Steam pressure measuring instrument 13c: Steam flow control valve 14: Fourth steam pipe 15: Fifth steam pipe 16: Sixth steam pipe 17: Seventh steam pipe 20: First water supply pipe 20a: Condensate pump 21: Second water supply Pipe 21a: water supply pump 22: third water supply pipe 23: fourth water supply pipe (water supply flow path)
23a: first water supply opening/closing valve (switching means)
23b: First feed water temperature measuring instrument (feed water thermometer side means)
24 : Fifth water supply pipe 24a : Second water supply temperature measuring instrument 25 : First bleed pipe 26 : Second bleed pipe 27 : Third bleed pipe 30 : Furnace 31 : Burner 32 : Flue 33 : Fuel pipe (fuel supply passage )
33a: Fuel flow control valve (fuel control means)
34: upstream superheater (upstream superheater)
35: final desuperheater (desuperheater)
36: final superheater (downstream superheater)
37: Reheater 38: Economizer (feed water heater)
39: Spray water pipe (spray water supply channel)
39a: Spray water volume control valve (spray water control 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 opening/closing valve (switching means)
50: circulation flow path 51: solar heat collector (solar heat heating unit)
52: Solar-powered feed water heater (first heat exchange section)
53: heat medium pump 54: heat medium temperature measuring instrument (heat medium temperature measuring means)
70: High pressure steam turbine (steam turbine)
71 : Intermediate-pressure steam turbine 72 : Low-pressure steam turbine 73 : Condenser 74 : Rotating shaft 81 : Boiler system 82 : Bypass piping (second bypass flow path)
83: 1st water supply opening/closing valve 84: 3rd water supply flow control valve 91: Heating unit using solar heat 92: Steam separator 93: Condenser 94: Water pipe 95: Second heat medium pump 100: Power plant 200: Power plant 300: Power plant

Claims (13)

a boiler that generates steam from feed water by burning fuel with a burner ;
a water supply channel through which the water supplied to the boiler flows;
a solar heating unit that heats a heat medium using heat generated by condensing sunlight;
a circulation flow path provided with the solar heating unit and circulating the heat medium at a predetermined constant flow rate;
a first heat exchange unit that exchanges heat between the water supply flowing through the water supply flow path and the heat medium flowing through the circulation flow path;
an adjustment means provided in the boiler for adjusting the temperature of the steam generated in the boiler according to the amount of solar radiation to the solar heating unit ,
The boiler includes a fuel supply passage that supplies fuel to the burner,
The boiler system , wherein the adjustment means includes fuel adjustment means provided in the fuel supply passage for adjusting the amount of fuel supplied to the burner . In the circulation flow path, all of the heat medium heated in the solar heating section is supplied to the first heat exchange section, and all of the heat medium heat-exchanged in the first heat exchange section is supplied to the solar heating section. 2. The boiler system of claim 1, wherein the boiler system is supplied to. The boiler includes a downstream superheater that superheats the steam, an upstream superheater that is provided upstream of the downstream superheater and superheats the steam, and is provided between the downstream superheater and the upstream superheater. a desuperheater that reduces the temperature of the steam supplied by the superheater, and a spray water supply flow path that extracts the feed water upstream of the upstream superheater and supplies it to the desuperheater,
The spray water supply channel is provided with spray water adjusting means for adjusting the amount of the water supply to be supplied to the desuperheater ,
3. The boiler system according to claim 1, wherein said adjusting means comprises said spray water adjusting means . The boiler includes a feed water heating unit that is provided upstream of the upstream superheater and heats the supplied feed water, and a feed water thermometer side means that measures the temperature of the feed water supplied to the feed water heating unit. , and
4. The boiler system according to claim 3, wherein the fuel adjustment means is controlled based on the temperature of the feed water measured by the feed water thermometer side means. 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,
5. The boiler system according to claim 3, wherein the fuel adjustment means is controlled based on the temperature of the heat medium measured by the heat medium temperature measuring means. a first bypass channel that bypasses the water supply channel;
a switching means for switching whether the water supply flows through the water supply channel or through the first bypass channel;
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;
The first heat exchange section is provided in the first bypass flow path,
The switching means is controlled so that the feed water 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. Item 6. The boiler system according to any one of items 5. a second heat exchange unit provided in the feed water flow path for exchanging heat between the steam extracted from a steam turbine driven by the steam generated in the boiler and the feed water;
A second bypass flow path provided to bypass the second heat exchange section and provided with the first heat exchange section,
6. The boiler system according to any one of claims 1 to 5, wherein a portion of the feed water supplied to the boiler flows through the second bypass passage. A steam separator provided between the solar heating unit and the first heat exchange unit,
The heat medium is water or steam,
The boiler system according to any one of claims 1 to 7, wherein the steam separator separates supplied water and steam and supplies the separated steam to the first heat exchange section. a boiler system according to any one of claims 1 to 8;
and a power generation unit that generates power using the steam generated by the boiler. a steam generating step of generating steam from feed water supplied through a feed water channel in a boiler by burning fuel with a burner ;
a heat medium heating step of heating a heat medium circulating in a circulation channel at a predetermined constant flow rate by a solar heating unit that heats the heat medium using heat generated by condensing sunlight;
a heat exchange step of exchanging heat between the water supply flowing through the water supply flow path and the heat medium flowing through the circulation flow path;
an adjusting step of adjusting the temperature of the steam generated in the boiler according to the amount of solar radiation to the solar heating unit by adjusting means provided in the boiler ;
The adjusting step includes adjusting the temperature of the steam by means of fuel adjusting means provided in a fuel supply passage for supplying fuel to the burner and adjusting the amount of fuel supplied to the burner. a boiler for generating steam from feed water;
a water supply channel through which the water supplied to the boiler flows;
a solar heating unit that heats a heat medium using heat generated by condensing sunlight;
a circulation flow path provided with the solar heating unit and circulating the heat medium at a predetermined constant flow rate;
a first heat exchange unit that exchanges heat between the water supply flowing through the water supply flow path and the heat medium flowing through the circulation flow path;
an adjustment means provided in the boiler for adjusting the temperature of the steam generated in the boiler according to the amount of solar radiation to the solar heating unit,
The boiler includes a downstream superheater that superheats the steam, an upstream superheater that is provided upstream of the downstream superheater and superheats the steam, and is provided between the downstream superheater and the upstream superheater. a desuperheater for reducing the temperature of the steam supplied by the superheater, a spray water supply passage for extracting the feed water upstream of the upstream superheater and supplying it to the desuperheater, and supplying fuel to the burner and a fuel supply path for
The spray water supply channel is provided with spray water adjusting means for adjusting the amount of the water supply to be supplied to the desuperheater,
The fuel supply path is provided with fuel adjustment means for adjusting the amount of fuel supplied to the burner,
A boiler system in which the adjustment means includes the spray water adjustment means and the fuel adjustment means. a boiler for generating steam from feed water;
a water supply channel through which the water supplied to the boiler flows;
a solar heating unit that heats a heat medium using heat generated by condensing sunlight;
a circulation flow path provided with the solar heating unit and circulating the heat medium at a predetermined constant flow rate;
a first heat exchange unit that exchanges heat between the water supply flowing through the water supply flow path and the heat medium flowing through the circulation flow path;
adjustment means provided in the boiler for adjusting the temperature of the steam generated in the boiler according to the amount of solar radiation to the solar heating unit;
a first bypass channel that bypasses the water supply channel;
a switching means for switching whether the water supply flows through the water supply channel or through the first bypass channel;
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;
The first heat exchange section is provided in the first bypass flow path,
A boiler system that controls the switching means so that the feed water 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. a boiler for generating steam from feedwater;
a water supply channel through which the water supplied to the boiler flows;
a solar heating unit that heats a heat medium using heat generated by condensing sunlight;
a circulation flow path provided with the solar heating unit and circulating the heat medium at a predetermined constant flow rate;
a first heat exchange unit that exchanges heat between the water supply flowing through the water supply flow path and the heat medium flowing through the circulation flow path;
adjustment means provided in the boiler for adjusting the temperature of the steam generated in the boiler according to the amount of solar radiation to the solar heating unit;
a second heat exchange unit provided in the feed water flow path for exchanging heat between the steam extracted from a steam turbine driven by the steam generated in the boiler and the feed water;
A second bypass flow path provided to bypass the second heat exchange section and provided with the first heat exchange section,
A boiler system in which part of the feed water supplied to the boiler flows through the second bypass flow path.

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