JP6178169B2 - Operation method of steam turbine plant - Google Patents

Description

  Embodiments described herein relate generally to a method for operating a steam turbine plant.

  In a steam turbine plant, in addition to heating a working medium supplied to a steam turbine with a boiler, auxiliary heating using solar heat has been proposed (for example, see Patent Document 1).

<First prior art>
FIG. 4 is a conceptual diagram showing a steam turbine plant according to the first prior art.

  As shown in FIG. 4, the steam turbine plant according to the first prior art includes a steam turbine 1, a condenser 2, a feed water heating unit 3, a boiler 4, and a solar heater 5. Here, the feed water heating unit 3 includes a first feed water heater 31, a second feed water heater 32, a third feed water heater 33, a fourth feed water heater 34, and a deaerator 311.

  In the steam turbine plant, the steam F1 (turbine exhaust) exhausted from the steam turbine 1 flows into the condenser 2 and is cooled by the condenser 2 to condense (condensate). Then, the water F2 (condensate) condensed in the condenser 2 is pressurized by the condensate pump P2 and transferred to the feed water heating unit 3.

  In the feed water heating unit 3, the water F 2 condensed in the condenser 2 is first heated by the fourth feed water heater 34, and the heated water F 34 is heated by the third feed water heater 33. Then, the gas dissolved in the water F <b> 33 heated by the third feed water heater 33 is deaerated by the deaerator 311. At that time, in the deaerator 311, the steam B1c (third extracted steam) extracted from the third extraction port A1c of the steam turbine 1 joins and the temperature rises. The water F311 deaerated by the deaerator 311 is pressurized by the feed water pump P311 and transferred to the second feed water heater 32, and then heated by the second feed water heater 32.

  And the steam turbine plant is comprised so that the water F32 heated with the 2nd feed water heater 32 may branch, and may flow into each of the 1st feed water heater 31 and the solar-heater 5. FIG. Of the water F32 heated by the second feed water heater 32, the water F32A (second water) flowing into the first feed water heater 31 is heated by the first feed water heater 31. On the other hand, out of the water F32 heated by the second feed water heater 32, the water F32B (third water) flowing into the solar heater 5 is heated by the solar heater 5. Then, both the water F31 heated by the first feed water heater 31 and the water F5 heated by the solar heater 5 merge.

  And the water (F31 + F5) which both the water F31 heated with the 1st feed water heater 31 and the water F5 heated with the solar-heater 5 flows in into the boiler 4 as boiler inflow water, and is a boiler. 4 is heated. Thereafter, the steam F4 generated by heating in the boiler 4 flows into the steam turbine 1, and the steam turbine 1 is driven.

  As described above, in the feed water heating unit 3, each of the fourth feed water heater 34, the third feed water heater 33, the deaerator 311, the second feed water heater 32, and the first feed water heater 31 is condensate. The water F2 condensed in the vessel 2 is sequentially arranged in series along the flow path flowing to the boiler 4.

  Moreover, both the 1st feed water heater 31 and the solar-heater 5 are located in a line with each other in the flow path through which the water F2 condensed by the condenser 2 flows to the boiler 4.

  In addition, although illustration is abbreviate | omitted in FIG. 4, the valve is suitably installed in the flow path of the fluid which flows through a steam turbine plant.

  More specifically, each part which comprises a steam turbine plant is demonstrated.

  The condenser 2 cools the steam F1 (turbine exhaust steam) flowing out from the exhaust outlet A1f of the steam turbine 1 using, for example, seawater pumped from the sea using a cooling water pump (not shown) as cooling water. Condense. The cooling water is heated by the condenser 2 and then returned to the sea.

  Of the feed water heating unit 3, in the first feed water heater 31, steam B 1 a (first bleed steam) extracted and discharged from the first extraction port A 1 a of the steam turbine 1, and water F 32 flowing out from the second feed water heater 32. Among them, heat exchange is performed with the water F32A branched into the first feed water heater 31 and flowing in. By this heat exchange, out of the water F32 flowing out from the second feed water heater 32, the water F32A flowing into the first feed water heater 31 is further heated by the first feed water heater 31. On the other hand, the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1 is cooled and condensed by heat exchange in the first feed water heater 31 and drain water B31 (first drain). It flows out to the 2nd feed water heater 32 as water).

  Of the feed water heating unit 3, in the second feed water heater 32, the steam B1b (second extracted steam) extracted and discharged from the second extraction port A1b located downstream of the first extraction port A1a in the steam turbine 1, Heat exchange is performed with the water F311 flowing out from the deaerator 311. By this heat exchange, the water F311 flowing out from the deaerator 311 is further heated by the second feed water heater 32. On the other hand, the steam B1b (second extraction steam) flowing out from the second extraction port A1b of the steam turbine 1 is cooled and condensed by heat exchange in the second feed water heater 32, and then from the first feed water heater 31. Together with the drain water B31 (first drain water) that flows in, the drain water B32 (second drain water) flows out to the deaerator 311.

  Of the feed water heating unit 3, in the deaerator 311, the steam B1c (third extraction steam) extracted and discharged from the third extraction port A1c located downstream of the second extraction port A1b in the steam turbine 1 is the third. The water F33 flowing out from the feed water heater 33 is degassed and joined to the water F33. The deaerator 311 is a kind of feed water heater in a broad sense, and removes gas dissolved in the water F33 heated by the third feed water heater 33 and performs heating.

  Of the feed water heating unit 3, in the third feed water heater 33, steam B1d (fourth extraction steam) extracted and discharged from the fourth extraction port A1d located downstream of the third extraction port A1c in the steam turbine 1, Heat exchange is performed with the water F34 flowing out from the fourth feed water heater 34. By this heat exchange, the water F34 flowing out from the fourth feed water heater 34 is further heated. On the other hand, the steam B1d (fourth extraction steam) flowing out from the fourth extraction port A1d of the steam turbine 1 is cooled and condensed by heat exchange in the third feed water heater 33, and drain water B33 (third drain) Water).

  Among the feed water heating units 3, in the fourth feed water heater 34, the steam B1e (fifth extraction steam) extracted and discharged from the fifth extraction port A1e located downstream of the fourth extraction port A1d in the steam turbine 1, Heat exchange is performed with the water F2 supplied from the condenser 2 via the condensate pump P2. By this heat exchange, the water F2 flowing out of the condenser 2 is heated by the fourth feed water heater 34. On the other hand, the steam B1e (fifth extraction steam) flowing out from the fifth extraction port A1e of the steam turbine 1 is cooled and condensed by heat exchange in the fourth feed water heater 34, and the third feed water heater 33 is It flows out as drain water B34 (fourth drain water) together with the drain water B33 (third drain water) that flows in. And the drain water B34 which flowed out from the 4th feed water heater 34 merges with the water F2 which flowed out from the condenser 2. FIG.

  The boiler 4 is a coal boiler, for example, and evaporates the inflowing water (F31 + F5) by using the combustion exhaust gas generated by the combustion of coal (for coal, combustion exhaust gas, combustion air, etc.). , Illustration is omitted). Steam F4 generated by heating in the boiler 4 is supplied to the inside from the supply port A1 of the steam turbine 1 and expands inside the steam turbine 1, and the pressure and temperature decrease. Thereby, the turbine rotor (not shown) accommodated in the steam turbine 1 rotates. The turbine rotor is connected to, for example, a generator (not shown), and power is generated in the generator by the rotation of the turbine rotor.

  In the solar heater 5, the water F 32 </ b> B branched into the solar heater 5 out of the heat medium M <b> 51 (for example, oil) heated by the collector 51 and the water F <b> 32 heated by the second feed water heater 32. Heat exchange takes place between the two. By this heat exchange, the water F32B branched into the solar heater 5 out of the water F32 heated by the second feed water heater 32 is heated by the solar heater 5. The water F5 that flows out after being heated by the solar heater 5 joins the water F31 that flows out after being heated by the first feed water heater 31, and then the combined water (F31 + F5) is heated by the boiler 4. . On the other hand, after the heat medium M51 heated by the heat collector 51 is cooled by the heat exchange in the solar heat heater 5, the cooled heat medium M5 is pressurized by the heat medium pump P5, It is transferred to the heat collector 51. The heat collector 51 collects solar heat by concentrating solar rays, and heats the heat medium M5 with the collected heat. The heat collector 1 includes, for example, a trough-type reflecting mirror (not shown), and is configured such that the reflecting mirror rotates following the sun.

  In the above steam turbine plant, when solar heat can be received sufficiently during the daytime, both the valve V5a installed on the inlet side of the solar heater 5 and the valve V5b installed on the outlet side are opened. Then, the heat medium pump P5 is operated. Thus, the water F32B flows into the solar heater 5 through the valve V5a and is heated by the solar heater 5. Then, the water F5 heated by the solar heater 5 flows toward the boiler 4 through the valve V5b.

  On the other hand, for example, when solar heat cannot be sufficiently received at night, both the valve V5a installed on the inlet side of the solar heater 5 and the valve V5b installed on the outlet side are fully closed. Then, the operation of the heat medium pump P5 is stopped. That is, the water F32B does not flow into the solar heater 5 by the fully closed valve V5a and is not heated by the solar heater 5.

  As described above, in the steam turbine plant, the water F32B is heated using solar heat in accordance with the solar heat reception.

  When the heating by the solar heater 5 is performed, the temperature of the water flowing into the boiler 4 becomes higher than when the heating is not performed. For this reason, the amount of fuel such as coal consumed in the boiler 4 can be reduced by heating with the solar heater 5.

  As described above, a cycle in which the feed water is heated using steam B1a, B1b, B1c, B1d, B1e (first to fifth extracted steam) extracted from the middle of the steam turbine 1 is called a regeneration cycle. Therefore, high cycle efficiency can be realized.

<Second prior art>
FIG. 5 is a conceptual diagram showing a steam turbine plant according to the second prior art.

  As shown in FIG. 5, in the second prior art, the steam turbine plant is different from the first prior art in the form of the steam turbine 1. The second prior art is the same as the first prior art except for this point and related points. For this reason, in the second prior art, the description of the portions overlapping with the first prior art will be omitted as appropriate.

  As shown in FIG. 5, in the steam turbine plant according to the second prior art, the steam turbine 1 is composed of a high-pressure turbine 11, an intermediate-pressure turbine 12, and a low-pressure turbine 13.

  In the steam turbine plant, the steam F4 generated by heating in the boiler 4 flows into the inside from the supply port A11 of the high-pressure turbine 11, expands inside the high-pressure turbine 11, and decreases in pressure and temperature.

  In the high-pressure turbine 11, steam B1a (extracted steam) flows out from the extraction port A11a. The steam B1a is cooled and condensed by the first feed water heater 31, and flows out to the second feed water heater 32 as drain water B31 (first drain water). In addition, in the high pressure turbine 11, the steam B1b flows out from the exhaust port A11b located downstream from the extraction port A11a. This steam B1b branches and flows into the second feed water heater 32 and the boiler 4 respectively. Among these, the steam B1b_1 (steam before reheating) flowing into the boiler 4 is heated again by the boiler 4, and then the heated steam F4 flows out to the intermediate pressure turbine 12. In contrast, the steam B1b_2 flowing into the second feed water heater 32 is cooled and condensed by the second feed water heater 32, and flows out to the deaerator 311 as drain water B32 (second drain water).

  Steam B4 (reheated steam) heated again by the boiler 4 flows into the inside from the supply port A12 of the intermediate pressure turbine 12, expands inside the intermediate pressure turbine 12, and the pressure and temperature decrease.

  In the intermediate pressure turbine 12, steam B1c (extracted steam) flows out from the extraction port A12a. This steam B1c (extracted steam) flows into the deaerator 311, degasses the water F33 heated by the third feed water heater 33, and joins the water F33. In the intermediate pressure turbine 12, the steam B1d flows out from the exhaust port A12b located downstream of the extraction port A12a. The steam B1d is cooled and condensed by the third feed water heater 33 and flows out to the fourth feed water heater 34 as drain water B33 (third drain water). In addition, the steam B12 flows out from the exhaust port A12c located downstream of the bleed port A12a. This steam B12 is supplied to the supply port A13 of the low-pressure turbine 13.

  The steam B12 (low pressure turbine inflow steam) flowing into the low pressure turbine 13 expands inside the low pressure turbine 13, and the pressure and temperature are reduced. Here, the low-pressure turbine 13 is a double-flow type, and the steam B12 (low-pressure turbine inflow steam) branches into two in the low-pressure turbine 13 and flows to the left and right.

  In the low-pressure turbine 13, steam B1e (extracted steam) flows out from the extraction port A13a. This steam B1e is cooled and condensed by the fourth feed water heater 34, and joins the water F2 in the condenser 2 as drain water B34 (fourth drain water). In the low pressure turbine 13, the steam F1 flows out from the exhaust port A13b located downstream of the extraction port A13a. The steam F1 is cooled and condensed in the condenser 2.

  In addition, as mentioned above, the cycle which reheats steam with the boiler 4 is called a reheat cycle, and can implement | achieve high turbine cycle efficiency.

  Moreover, although the case where the boiler 4 is a coal boiler was demonstrated in the 1st prior art and the 2nd prior art, it may be a case where any other heat source is used.

JP 2008-39367 A JP 2008-121483 A

  In general, during the summer daytime, there is a large demand for power, so it is necessary to increase the amount of power generation.

  Since a large amount of solar heat can be collected during the daytime in the summer, the above-described steam turbine plant can reduce the fuel consumed by the boiler by using solar heat. However, even when a large amount of solar heat can be received, the temperature of the steam flowing out from the boiler outlet cannot be increased without limitation due to hardware limitations. Similarly, the flow rate of steam that can flow into the inlet of the steam turbine or the first stage turbine stage cannot be increased sufficiently. As a result, in the steam turbine plant described above, it may be difficult to sufficiently increase the output of the steam turbine.

  Accordingly, the problem to be solved by the present invention is that when a large amount of solar heat can be collected, the output of the steam turbine can be increased by effectively using the solar heat. It is to provide a driving method.

The steam turbine plant of the present embodiment includes a steam turbine, a boiler, a condenser, a pump, a feed water heating unit, and a solar heater. The boiler produces steam that flows into the steam turbine. The condenser cools and condenses (that is, liquefies) the exhaust steam exhausted from the steam turbine. The pump conveys the water condensed in the condenser to the boiler. The feed water heating unit heats the water with the extracted steam extracted from the middle of the steam turbine before the water conveyed from the condenser to the boiler by the pump flows into the boiler. The solar heater heats the water with a heat source derived from solar heat before the water conveyed from the condenser to the boiler by the pump flows into the boiler. Here, the feed water heater has a feed water heater installed in parallel with the solar heater in a flow path in which water condensed in the condenser is conveyed to the boiler by a pump. In the operation method of the steam turbine plant of this embodiment, in the feed water heater installed in parallel with the solar heater, both the extracted steam and the water conveyed from the condenser to the boiler by the pump circulate. The steam turbine plant is operated with all the water flowing through the solar heater while stopping.

FIG. 1 is a conceptual diagram showing a steam turbine plant according to the first embodiment. FIG. 2 is a conceptual diagram showing a steam turbine plant according to the second embodiment. FIG. 3 is a conceptual diagram showing a steam turbine plant according to a third embodiment. FIG. 4 is a conceptual diagram showing a steam turbine plant according to the first prior art. FIG. 5 is a conceptual diagram showing a steam turbine plant according to the second prior art.

  Embodiments will be described with reference to the drawings.

<First Embodiment>
[A] Configuration of Steam Turbine Plant FIG. 1 is a conceptual diagram showing a steam turbine plant according to the first embodiment.

  In FIG. 1, the part shown with the broken line is a part which comprises a steam turbine plant similarly to the part shown with the continuous line. In FIG. 1, in the operation method of the steam turbine plant, a portion where the fluid flows is indicated by a solid line, and a portion where the fluid does not flow is indicated by a broken line.

  As shown in FIG. 1, the steam turbine plant of the present embodiment is configured in the same manner as the first prior art (see FIG. 4). In the present embodiment, as shown in FIG. 1, the operation method of the steam turbine plant is different from the case of the first prior art (see FIG. 4). That is, the part which flows a fluid in each part which comprises a steam turbine plant differs from 1st prior art (refer FIG. 4). The present embodiment is the same as the first prior art except for this point and points related thereto. For this reason, in this embodiment, the description overlapping with the first prior art is omitted as appropriate.

  As shown in FIG. 1, the steam turbine plant includes a steam turbine 1, a condenser 2, a feed water heating unit 3, a boiler 4, and a solar heater 5 as in the case of the first prior art. Have. The feed water heater 3 includes a first feed water heater 31, a second feed water heater 32, a third feed water heater 33, a fourth feed water heater 34, and a deaerator 311.

  As shown in FIG. 1, each part which comprises a steam turbine plant is comprised similarly to the case of a 1st prior art.

  In the steam turbine plant of the present embodiment, the steam F1 exhausted from the steam turbine 1 is cooled and condensed by the condenser 2, and the water F2 condensed by the condenser 2 is supplied to the condensate pump P2 and the feed water. It is conveyed to the boiler 4 by the pump P311. The water F <b> 2 conveyed from the condenser 2 to the boiler 4 is heated in the feed water heating unit 3 before flowing into the boiler 4. In the feed water heating unit 3, heating is performed using steam B1a to B1e (first to fifth extracted steam) extracted from the middle of the steam turbine 1 as a heat source. In addition, the water F <b> 2 conveyed from the condenser 2 to the boiler 4 is heated in the solar heater 5 before flowing into the boiler 4. In the solar heater 5, heating is performed using the heat medium M51 heated by the solar heat collected by the heat collector 51 as a heat source (a heat source derived from solar heat). Then, the steam F <b> 4 that flows into the steam turbine 1 is produced by the boiler 4.

  Here, the feed water heating unit 3 includes first to fourth feed water heaters 31 to 34 and a deaerator 311 (a plurality of feed water heaters). These are the fourth feed water heater 34, the third feed water heater 33, the deaerator 311 and the second feed water heater in the flow path through which the water F2 condensed in the condenser 2 is conveyed to the boiler 4. 32 and the first water heater 31 are arranged in series in this order.

  And in this embodiment, the steam B1a extracted most upstream in the steam turbine 1 among the 1st to 4th feed water heaters 31-34 and the deaerator 311 (a plurality of feed water heaters) A circulating first water heater 31 is installed in parallel to the solar heater 5.

[B] Operation Method of Steam Turbine Plant In the steam turbine plant described above, there may be a case where a sufficient amount of solar heat can be received during the daytime in summer. For example, the amount of heat that originally heats the water F32B (third water) by the solar heater 5 is equal to the amount of heat that heats the water F32A (second water) by the first feed water heater 31. In addition, the heat collector 51 may collect heat.

  In such a case, when the steam turbine plant is operated in the present embodiment, the plurality of valves V31a, V31b, VB1a, VB31 are fully closed as shown by broken lines in FIG. Do not circulate. That is, the steam turbine plant is operated without using the first feed water heater 31.

  Specifically, in the first feed water heater 31, both the valve V31a installed on the inlet side of the flow path through which the water F32A flows and the valve V31b installed on the outlet side are all closed. Further, in the first feed water heater 31, a valve VB1a installed on the inlet side of the flow path through which the steam B1a (first extracted steam) flowing out from the first extraction port A1a of the steam turbine 1 flows is installed on the outlet side. Both of the valves VB31 are closed.

  If it demonstrates in detail, the valve V31a is installed in the flow path of the water F32A which branches and flows into the 1st feed water heater 31, and all this valve V31a is closed in this embodiment. Moreover, the valve V31b is installed in the flow path of the water F31 that flows out after being heated by the first feed water heater 31, and all the valves V31b are closed.

  Further, the valve VB1a is installed in a flow path where the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1 flows to the first feed water heater 31 of the feed water heating unit 3, In the embodiment, all the valves VB1a are closed. Further, the valve VB31 is a drain water B31 (first drain water) that flows out after the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1 is cooled and condensed by the first feed water heater 31. The valve VB31 is all closed.

  Thereby, in this embodiment, the water F32 which flowed out from the 2nd feed water heater 32 branches to the 1st feed water heater 31, and does not flow in. In the present embodiment, the entire amount of water F32 flowing out from the second feed water heater 32 flows to the solar heater 5 as water F32B (third water) flowing into the solar heater 5 (that is, F32B = F32). .

  Then, the water F <b> 32 </ b> B (third water) flowing into the solar heater 5 is heated by the solar heater 5. Thereafter, the water F <b> 5 heated by the solar heater 5 flows to the boiler 4. In the present embodiment, the water F31 does not flow out from the first feed water heater 31. For this reason, the water (F31 + F5) which the water F31 which flowed out from the 1st feed water heater 31 and the water F5 which flowed out from the solar-heater 5 merged into the boiler 4 does not flow in, but from the solar-heater 5 Only the water F5 that has flowed out flows into the boiler 4.

  In addition, in this embodiment, the steam B1a (first extraction steam) does not flow out from the first extraction port A1a of the steam turbine 1 and does not flow into the first feed water heater 31.

  As described above, in addition to fully closing the plurality of valves V31a, V31b, VB1a, and VB31, in this embodiment, the flow rate of the heat medium M5 is adjusted. For example, the flow rate of the heat medium M5 is adjusted by adjusting the output of the heat medium pump P5. In addition, the flow rate of the heat medium M5 may be adjusted by adjusting the opening degree of a heat medium flow rate adjustment valve (not shown) installed in the flow path of the heat medium M5.

  Here, the solar heater 5 heats the water F311B (third water) by the same amount of heat as that originally applied by the steam B1a (first extraction steam) flowing out from the first extraction port A1a. As is done, the flow rate of the heat medium M5 is adjusted. That is, after the valves V31a, V31b, VB1a, and VB31 are fully closed, the amount of heat applied to the water F5 flowing into the boiler 4 is heated in the original state (that is, steam B1a (first extraction steam), And the flow volume adjustment of the heat medium M5 is performed so that it may become the same as the state which is not heated by the solar-heater 5).

  Thereby, the water F5 (boiler inflow water) which flows into the boiler 4 becomes the same temperature as when only the 1st feed water heater 31 is heated.

  Thus, in this embodiment, the temperature of the water F5 (boiler inflow water) flowing into the boiler 4 is heated in the original state (that is, the steam B1a (first extraction steam), and by the solar heater 5 The heating amount heated by the boiler 4 is the same, and the amount of fuel (here, coal) consumed by the boiler 4 is also the same.

[C] Summary (effects, etc.)
As described above, in the present embodiment, for example, when the heating amount by the solar heater 5 is the same as or larger than the heating amount by the extracted steam, the solar heater 5 is installed in parallel with the solar heater 5. In the first feed water heater 31, the steam B 1 a (first extracted steam) extracted from the middle of the steam turbine 1 is stopped from flowing. Moreover, in the 1st feed water heater 31, the water F2 (here F32A) conveyed from the condenser 2 to the boiler 4 is stopped | circulated.

  On the other hand, in the second to fourth feed water heaters 32, 33, 34 and the deaerator 311 other than the first feed water heater 31, steam B 1 b, B 1 c, extracted from the middle of the steam turbine 1, B1d and B1e (second to fifth extraction steam) are circulated. Further, in the second to fourth feed water heaters 32, 33, 34 and the deaerator 311, water F2 (here, F2, F34, F33, F311) conveyed from the condenser 2 to the boiler 4 is used. , F32). Further, in the solar heater 5, water F2 (here, F32B = F32) conveyed from the condenser 2 to the boiler 4 is circulated.

  As described above, in the operation method of the steam turbine plant of the present embodiment, the steam B1a (first extracted steam) does not flow into the first feed water heater 31 from the first extraction port A1a of the steam turbine 1. For this reason, in this embodiment, the vapor | steam for the part which flows out out of 1st extraction opening A1a in the steam turbine 1 flows downstream rather than 1st extraction opening A1a. As a result, among the plurality of turbine stages, the steam flow rate increases in the turbine stage located downstream of the first extraction port A1a. Therefore, in this embodiment, the turbine output can be increased.

  In the steam turbine plant of the present embodiment (original operation (see FIG. 4)), the amount of heat for heating the water F32B (third water) by the solar heater 5 is originally the water F32A by the first feed water heater 31. There is a case where heat can be received (for example, summer daytime) so that the amount of heat is equal to or greater than the amount of heat for heating (second water). In this case, since the temperature of the water F5 flowing into the boiler 4 can be increased, the amount of fuel (here, coal) consumed by the boiler 4 can be reduced. At this time, the flow rate is often adjusted so that the flow rate of the heat medium M5 increases. Therefore, not only can the amount of fuel consumed in the boiler 4 be increased by using a large amount of solar heat, but the output of the steam turbine 1 can be increased, and in some cases, the amount of fuel consumed in the boiler 4 And the output of the steam turbine 1 can be increased.

  In the steam turbine plant of the present embodiment, by performing heating using the first feed water heater 31 without using the solar heat heater 5 among the first feed water heater 31 and the solar heat heater 5, “operation I Can be done. In addition, by performing heating using both the first feed water heater 31 and the solar heat heater 5, “Operation II” can be performed. In this “operation II”, since the amount of fuel used in the boiler 4 can be reduced as compared with “operation I”, the turbine efficiency can be improved more than in “operation I”. If the amount of heat collected by the heat collector 51 is sufficiently large and the amount of heating by the solar heater 5 and the amount of heating by the first feed water heater 31 are the same, the first feed water heater 31 is “Operation III” can be performed by heating using the solar heater 5 without using it, and by using the same fuel amount as that of “Operation I”. In this “operation III”, the turbine output can be improved as compared with the cases of “operation I” and “operation II”. And when the amount of heat collection in the heat collector 51 becomes larger than that in “operation III”, and the amount of heating in the solar heat heater 5 can be made larger than the amount of heating in the first feed water heater 31. In the same manner as in the case of “Operation III”, heating is performed using the solar heater 5 without using the first feed water heater 31, and the amount of fuel is reduced as compared with “Operation I” and “Operation III”. By doing this, you can do “driving IV”. In this “operation IV”, the output remains high, and the turbine efficiency can be improved as compared with the case of “operation III”.

  In addition, if the solar heater 5 is not installed in the steam turbine plant, the temperature of the water F5 flowing into the boiler 4 unless the steam B1a (first extraction steam) is circulated to the first feed water heater 31. Decreases. For this reason, it is necessary to increase the heating amount in the boiler 4 by the reduced amount. As a result, even if the output increases, the turbine cycle efficiency decreases and the amount of fuel increases.

  In the operation method of the steam turbine plant of the present embodiment, the amount of power generation can be increased without increasing the amount of fuel consumed by the boiler 4 at the time when the demand for electric power is large, such as during the daytime in summer.

[D] Modification [D-1] Modification 1-1
In the present embodiment, the case where the feed water heating unit 3 includes five feed water heaters (first to fourth feed water heaters 31 to 34 and a deaerator 311) is described, but the present invention is not limited thereto. Absent. The feed water heating unit 3 may include more than five feed water heaters or fewer than five. That is, the feed water heater 3 may have one feed water heater.

[D-2] Modification 1-2
The “method of operating a steam turbine plant” shown in the present embodiment may be applied to the case of the second prior art.

Second Embodiment
[A] Configuration FIG. 2 is a conceptual diagram showing a steam turbine plant according to a second embodiment.

  In FIG. 2, the part shown with a broken line is a part which comprises a steam turbine plant similarly to the part shown with the continuous line. In FIG. 2, in the operation method of the steam turbine plant, a portion where the fluid flows is indicated by a solid line, and a portion where the fluid does not flow is indicated by a broken line (similar to FIG. 1).

  As shown in FIG. 2, the steam turbine plant of the present embodiment is partially different from the first embodiment (see FIG. 1). Moreover, in this embodiment, the operating method of a steam turbine plant differs from the case of 1st Embodiment. The present embodiment is the same as that of the first embodiment except for this point and points related thereto. For this reason, in this embodiment, about the part which overlaps 1st Embodiment, description is abbreviate | omitted suitably.

  As shown in FIG. 2, in the present embodiment, as in the case of the first embodiment, the fourth feed water heater 34, the third feed water heater 33, the deaerator 311, the second feed water heater 32, and the first feed water heater 32 are used. One feed water heater 31 is arranged in series along a flow path in which water F2 condensed in the condenser 2 flows to the boiler 4.

  However, unlike the case of the first embodiment, the solar heater 5 is configured such that both the first feed water heater 31 and the second feed water heater 32 are provided in the flow path where the water F2 condensed in the condenser 2 flows to the boiler 4. In contrast, they are lined up in parallel.

  That is, in the steam turbine plant of the present embodiment, after the water F311 flowing out from the deaerator 311 is pressurized by the feed water pump P311, the water F311 branches and each of the second feed water heater 32 and the solar heat heater 5 is branched. It is configured to flow. The water F311 flowing out from the deaerator 311 flows into the second feed water heater 32 after being branched and heated, and then the water F32 heated by the second feed water heater 32 flows into the first feed water heater 31. .

[B] Operation Method of Steam Turbine Plant As described above, a steam turbine plant may be able to receive a sufficiently large amount of solar heat during the daytime in summer. For example, originally, the amount of heat equal to the amount of heat obtained by adding the amount of heat for sequentially heating the water F311A and F32 in the second feed water heater 32 and the first feed water heater 31 to the amount of heat for heating the water F32B by the solar heater 5. In some cases, the heat collector 51 can collect heat.

  In such a case, in this embodiment, as shown by a broken line in FIG. 2, the plurality of valves V32a, V31b, VB1b, VB32, VB1a, VB31 are fully closed, and the first feed water heater 31 and the second feed water heating are performed. The fluid is not circulated to each of the containers 32. That is, the steam turbine plant is operated without using the first feed water heater 31 and the second feed water heater 32.

  Specifically, in the set of the first feed water heater 31 and the second feed water heater 32 arranged in series, the valve V32a installed on the inlet side of the flow path through which the water F311A flows, and the valve installed on the outlet side Both V31b and all are closed. Further, in the first feed water heater 31, a valve VB1a installed on the inlet side of the flow path through which the steam B1a (first extracted steam) flowing out from the first extraction port A1a of the steam turbine 1 flows, and installed on the outlet side. Both of the valves VB31 are closed. Further, in the second feed water heater 32, a valve VB1b installed on the inlet side of the flow path through which the steam B1b (second extracted steam) flowing out from the second extraction port A2a of the steam turbine 1 flows, and an outlet side are installed. Both of the valves VB32 are closed.

  More specifically, the valve V32a is installed in the flow path of the water F311A (second water) that branches into the second feed water heater 32 out of the water F311 that flows out from the deaerator 311; In this embodiment, all the valves V32a are closed. Further, the valve V31b is installed in the flow path of the water F31 that flows out after being heated by the first feed water heater 31, and in the present embodiment, all the valves V31b are closed.

  The valve VB1b is installed in a flow path where the steam B1b (second extracted steam) flowing out from the second extraction port A1b of the steam turbine 1 flows to the second feed water heater 32 of the feed water heating unit 3, and this embodiment Now, all the valves VB1b are closed. Further, the valve VB32 has a drain water B32 (second drain water) that flows out after the steam B1b (second extracted steam) flowing out from the second extraction port A1b of the steam turbine 1 is cooled and condensed by the second feed water heater 32. In this embodiment, all the valves VB32 are closed.

  Further, the valve VB1a is installed in a flow path where the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1 flows to the first feed water heater 31 of the feed water heating unit 3, In the embodiment, all the valves VB1a are closed. Further, the valve VB31 is a drain water B31 (first drain water) that flows out after the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1 is cooled and condensed by the first feed water heater 31. In this embodiment, all the valves VB31 are closed.

  Thereby, in this embodiment, the water F311 which flowed out from the deaerator 311 does not flow into the 2nd feed water heater 32 and the 1st feed water heater 31. In the present embodiment, the entire amount of water F311 flowing out from the deaerator 311 flows to the solar heater 5 as water F311B (third water) flowing into the solar heater 5 (that is, F311B = F311). Then, the water F311B (third water) flowing into the solar heater 5 is heated by the solar heater 5. Thereafter, the water F5 heated by the solar heater 5 flows to the boiler 4 as boiler inflow water.

  In the present embodiment, since the water F311A branched to the second feed water heater 32 does not flow, the water F32 does not flow into the first feed water heater 31 and the water F31 flows out from the first feed water heater 31 to the boiler 4. do not do. For this reason, the water (F31 + F5) which the water F31 which flowed out from the 1st feed water heater 31 and the water F5 which flowed out from the solar-heater 5 merged does not flow into the boiler 4, but flowed out from the solar-heater 5 Water F5 flows into the boiler 4.

  Furthermore, in the present embodiment, the steam B1a (first extraction steam) does not flow out from the first extraction port A1a of the steam turbine 1 and does not flow into the first feed water heater 31. Further, the steam B1b (second extraction steam) does not flow out from the second extraction port A1b of the steam turbine 1 and does not flow into the second feed water heater 32.

  As described above, in addition to the plurality of valves V32a, V31b, VB1b, VB32, VB1a, and VB31 being fully closed, in this embodiment, the flow rate of the heat medium M5 is adjusted as in the case of the first embodiment. To do.

  Here, the same amount of heat as the amount of heat originally added by the steam B1a (first extraction steam) flowing out from the first extraction port A1a and the steam B1b (second extraction steam) flowing out from the second extraction port A1b. Thus, the flow rate of the heat medium M5 is adjusted such that the solar heater 5 heats the water F311B (third water). That is, after the valves V32a, V31b, VB1b, VB32, VB1a, VB31 are fully closed, the amount of heat applied to the water F5 flowing into the boiler 4 is the original state (that is, steam B1a, B1b (first extraction steam) , The second extraction steam), and the flow rate of the heat medium M5 is adjusted so as to be the same as in the state where there is no heating by the solar heater 5).

  Thereby, the water F5 (boiler inflow water) which flows into the boiler 4 becomes the same temperature when it heats only using both the 1st feed water heater 31 and the 2nd feed water heater 32. FIG.

  Thus, in this embodiment, as in the case of the first embodiment, the temperature of the water F5 (boiler inflow water) flowing into the boiler 4 is the original state (ie, steam B1a, B1b (first extraction steam). , The second extraction steam) and the heating by the solar heater 5 is the same), the heating amount heated by the boiler 4 is the same, and the fuel consumed in the boiler 4 (here, coal ) Is the same.

[C] Summary (effects, etc.)
As described above, in the steam turbine plant of the present embodiment, the first feed water heater 31 and the second feed water heater 32 are installed in parallel to the solar heater 5. That is, the solar heater 5 is a steam B1a that is extracted at the most upstream side in the steam turbine 1 among the plurality of feed water heaters (first to fourth feed water heaters 31 to 34 and deaerator 311). It is installed so as to be in parallel with the first feed water heater 31 through which (first extraction steam) flows. At the same time, in the solar heater 5, in the steam turbine 1, the steam B1b (second extracted steam) extracted on the upstream side next to the steam B1a (first extracted steam) flowing to the first feed water heater 31 is circulated. Installed in parallel with the second feed water heater 32.

  When the steam turbine plant is operated, the first feed water heater 31 stops the steam B1a (first extracted steam) extracted from the middle of the steam turbine 1 from flowing. Moreover, in the 1st feed water heater 31, the water F2 (here F32) conveyed from the condenser 2 to the boiler 4 is stopped | circulated.

  At the same time, in the second feed water heater 32, the steam B1b (second extracted steam) extracted from the middle of the steam turbine 1 is stopped from flowing. Moreover, in the 2nd feed water heater 32, the water F2 (here F311A) conveyed from the condenser 2 to the boiler 4 stops flowing.

  On the other hand, in the 3rd feed water heater 33, the 4th feed water heater 34, and the deaerator 311 except the 1st feed water heater 31 and the 2nd feed water heater 32, in the middle of the steam turbine 1 The steam B1c, B1d, B1e (third to fifth extracted steam) extracted from is circulated. Moreover, in the 3rd feed water heater 33, the 4th feed water heater 34, and the deaerator 311, the water F2 (here F2, F34, F33) conveyed from the condenser 2 to the boiler 4 distribute | circulates. Let Furthermore, in the solar heater 5, water F2 (here, F311B = F311) conveyed from the condenser 2 to the boiler 4 is circulated.

  As described above, in the operation method of the steam turbine plant of the present embodiment, the steam B1a (first extracted steam) does not flow into the first feed water heater 31 from the first extraction port A1a of the steam turbine 1. Further, the steam B 1 b (second extracted steam) does not flow into the second feed water heater 32 from the second extraction port A 1 b of the steam turbine 1. For this reason, in the present embodiment, the steam that flows out from the first extraction port A1a in the steam turbine 1 flows downstream from the first extraction port A1a, and the steam that flows out from the second extraction port A1b, It flows downstream from the second extraction port A1b. As a result, among the plurality of turbine stages, the steam flow rate increases in the turbine stage located downstream of the first extraction port A1a and the second extraction port A1b. Therefore, in this embodiment, the turbine output can be increased.

  In the steam turbine plant of this embodiment, the amount of heat that heats the water F32B by the solar heater 5 is originally the same as the amount of heat that sequentially heats the water F311A and F32 in the second feedwater heater 32 and the first feedwater heater 31. In some cases, heat can be received so that the amount of heat is larger. In this case, since the temperature of the water F5 flowing into the boiler 4 can be increased, the amount of fuel (here, coal) consumed by the boiler 4 can be reduced. At this time, the flow rate is often adjusted so that the flow rate of the heat medium M5 increases. Therefore, not only can the amount of fuel consumed in the boiler 4 be increased by using a large amount of solar heat, but the output of the steam turbine 1 can be increased, and in some cases, the amount of fuel consumed in the boiler 4 And the output of the steam turbine 1 can be increased.

  If the solar heater 5 is not installed in the steam turbine plant, the circulation of the steam B1a (first extraction steam) to the first feed water heater 31 and the second feed water heater 32 are performed. If the steam B1b (second extracted steam) is not circulated, the temperature of the water F5 flowing into the boiler 4 is lowered. For this reason, it is necessary to increase the heating amount in the boiler 4 by the reduced amount. As a result, even if the output increases, the turbine cycle efficiency decreases and the amount of fuel increases.

  In the operation method of the steam turbine plant of the present embodiment, the amount of power generation can be increased without increasing the amount of fuel consumed by the boiler 4 at the time when the demand for electric power is large, such as during the daytime in summer. In the present embodiment, the number can be increased as compared with the case of the first embodiment.

[D] Modification [D-1] Modification 2-1
In the operation method of the steam turbine plant of the present embodiment, all the valves VB31 (first drain valve) are closed (see FIG. 2), but the present invention is not limited to this. The valve VB31 (first drain valve) need not be fully closed.

[D-2] Modification 2-2
In the present embodiment, the case where the feed water heating unit 3 includes five feed water heaters (first to fourth feed water heaters 31 to 34 and a deaerator 311) is described, but the present invention is not limited thereto. Absent.

  This embodiment can be applied when the feed water heating unit 3 has n (n is a natural number of 1 or more) feed water heaters (first to nth feed water heaters).

  In this case, the steam turbine 1 is provided with n extraction ports from which steam extracted from the middle of the steam turbine 1 (extracted steam) flows out from the upstream side to the downstream side.

  Each of the n feed water heaters (first to nth feed water heaters) is extracted steam (first to nth) extracted from each of the n extraction ports (first to nth extraction ports). Each of the extracted steam).

  Each of the n feed water heaters (first to nth feed water heaters) is installed in series in a flow path in which water F2 condensed in the condenser 2 is conveyed to the boiler 4 by the pump P2. The Here, the water F2 condensed in the condenser 2 is configured so as to flow through each of the n-th to first feed water heaters and be heated.

  Of the n feed water heaters, each of the first to mth extraction ports located from the upstream side to the downstream side in the steam turbine 1 up to m-th (m is a natural number from 1 to n). Each of the first to m-th feed water heaters into which the steam (first to m-th extraction steam) flowing out of the solar gas flows in is installed in parallel with the solar heater 5.

  When operating this steam turbine plant, the steam extracted from the middle of the steam turbine 1 (first to mth extracted steam) is stopped from flowing in each of the first to mth feed water heaters. At the same time, in each of the first to m-th feed water heaters, the water F2 transported from the condenser 2 to the boiler 4 is stopped from flowing.

  On the other hand, when there is a feed water heater other than the 1st to m-th feed water heaters, steam extracted from the middle of the steam turbine 1 in the feed water (extracted steam other than the 1st to m-th) Circulate. Moreover, the water F2 conveyed from the condenser 2 to the boiler 4 is distribute | circulated in feed water heaters other than the 1st to m-th feed water heater. Furthermore, in the solar heater 5, the water F2 conveyed from the condenser 2 to the boiler 4 is circulated.

  In this modification, the case where n is 5 and m is 2 corresponds to the second embodiment.

[D-3] Modification 2-3
The operation method of the steam turbine plant shown in the present embodiment may be applied to the case of the second prior art.

<Third Embodiment>
[A] Configuration, etc. FIG. 3 is a conceptual diagram showing a steam turbine plant according to a third embodiment.

  In FIG. 3, the part shown with a broken line is a part which comprises a steam turbine plant similarly to the part shown with the continuous line. In FIG. 3, in the operation method of the steam turbine plant, the portion where the fluid flows is indicated by a solid line, and the portion where the fluid does not flow is indicated by a broken line (similar to FIGS. 1 and 2).

  As shown in FIG. 3, the steam turbine plant of the present embodiment is partly different from the first embodiment (see FIG. 1). Moreover, in this embodiment, the operating method of a steam turbine plant differs from the case of 1st Embodiment. The present embodiment is the same as the above embodiment except for this point and points related thereto. For this reason, in this embodiment, about the part which overlaps the said embodiment, description is abbreviate | omitted suitably.

  As shown in FIG. 3, in the present embodiment, as in the case of the first embodiment, the fourth feed water heater 34, the third feed water heater 33, the deaerator 311, the second feed water heater 32, and the first feed water heater 32 are used. One feed water heater 31 is arranged in series along a flow path in which water F2 condensed in the condenser 2 flows to the boiler 4.

  However, unlike the case of the first embodiment, the steam turbine plant of the present embodiment includes a plurality of solar heaters 5A and 5B.

  Of the two solar heaters 5A and 5B, the first solar heater 5A is arranged in parallel to the first feed water heater 31 in the flow path where the water F2 condensed in the condenser 2 flows to the boiler 4. They are installed side by side.

  On the other hand, out of the two solar heaters 5A and 5B, the second solar heater 5B is in a flow path where the water F2 condensed in the condenser 2 flows to the boiler 4 with respect to the second feed water heater 32. Installed in parallel.

  As described above, in the steam turbine plant of the present embodiment, the water F311 flowing out from the deaerator 311 is pressurized by the feed water pump P311 and then branches, and the second feed water heater 32 and the second solar heating are branched. It is comprised so that it may flow to each with the container 5B. And the steam turbine plant of this embodiment is comprised so that the water F32 which flowed out the 2nd feed water heater 32 and the water F5b which flowed out the 2nd solar-heater 5B may join.

  Further, in the steam turbine plant of the present embodiment, after the water F32 flowing out of the second feed water heater 32 and the water F5b flowing out of the second solar heater 5B merge, the merged water (F32 + F5b) branches. And it is comprised so that it may flow through each of the 1st feed water heater 31 and the 1st solar-heater 5A. And the steam turbine plant of this embodiment is comprised so that the water F31 which flowed out the 1st feed water heater 31 and the water F5a which flowed out 5A of 1st solar-heaters may join.

  In the present embodiment, the first solar heater 5A and the second solar heater 5B are installed so as to be arranged in series along the flow path of the heat medium M5.

  For this reason, the heat medium M51 (for example, oil) heated by the heat collector 51 first flows into the first solar heater 5A and is cooled by heat exchange with the water F32B. Then, the heat medium M5a cooled by the first solar heater 5A flows into the second solar heater 5B and is cooled by heat exchange with the water F311B. Thereafter, the heat medium M5b cooled by the second solar heater 5B is pressurized by the heat medium pump P5 and transferred to the heat collector 51.

[B] Operation method of steam turbine plant About said steam turbine plant, a some operation | movement can be selected and performed.

[B-1] First Operation As described above, in the steam turbine plant, the solar collector may be able to receive a large amount of solar heat during the daytime in summer. For example, as in the case of the first embodiment, the amount of heat that originally heats the water F32B with the first solar heater 5A is equal to or greater than the amount of heat that heats the water F32A with the first feed water heater 31. In some cases, the heat collector 51 can collect heat.

  In this case, as in the case of the first embodiment, the plurality of valves V31a, V31b, VB1a, VB31 are fully closed, and the fluid is not circulated to the first feed water heater 31, and the operation of the steam turbine plant is performed. I do. That is, the steam turbine plant is operated without using the first feed water heater 31. The output of the steam turbine 1 increases from the original state.

[B-2] Second operation More solar heat can be received than in the above case, and the amount of heat that heats the water F32B with the first solar heater 5A and the amount of heat that heats the water F311B with the second solar heater 5B. So that the amount of heat that heats the water F32A by the first feed water heater 31 and the amount of heat that heats the water F311A by the second feed water heater 32 are the same or more. In some cases, the heat collector 51 can further collect heat.

  In such a case, in the present embodiment, as indicated by broken lines in FIG. 3, the first feed water heating is performed by fully closing the plurality of valves V32a, V32b, V31a, V31b, VB1b, VB32, VB1a, and VB31. In addition to not allowing fluid to flow through the vessel 31, no fluid is allowed to flow through the second feed water heater 32. That is, the steam turbine plant is operated without using both the first feed water heater 31 and the second feed water heater 32 (FIG. 3 shows the case of the second operation).

  Specifically, in the second feed water heater 32, both the valve V32a installed on the inlet side of the flow path through which the water F311A flows and the valve V32b installed on the outlet side are all closed. Further, in the second feed water heater 32, a valve VB1b installed on the inlet side of the flow path through which the steam B1b (second extracted steam) flowing out from the second extraction port A1b of the steam turbine 1 flows, and an outlet side are installed. Both of the valves VB32 are closed.

  In addition to this, in the first feed water heater 31, both the valve V31a installed on the inlet side of the flow path through which the water F32A flows and the valve V31b installed on the outlet side are all closed. Further, in the first feed water heater 31, a valve VB1a installed on the inlet side of the flow path through which the steam B1a (first extracted steam) flowing out from the first extraction port A1a of the steam turbine 1 flows, and installed on the outlet side. Both of the valves VB31 are closed.

  If it demonstrates in detail, the valve V32a is installed in the flow path of the water F311A which branches and flows into the 2nd feed water heater 32, and all this valve V32a is closed in this embodiment. Moreover, the valve V32b is installed in the flow path of the water F32 that flows out after being heated by the second feed water heater 32, and all the valves V32b are closed.

  The valve VB1b is installed in a flow path in which steam B1b (second extracted steam) flowing out from the second extraction port A1b of the steam turbine 1 flows to the second feed water heater 32. In this embodiment, the valve VB2a Close all. Further, the valve VB32 has a drain water B32 (second drain water) that flows out after the steam B1b (second extracted steam) flowing out from the second extraction port A1b of the steam turbine 1 is cooled and condensed by the second feed water heater 32. The valve VB32 is all closed.

  The valve V31a is installed in the flow path of the water F32A that branches and flows into the first feed water heater 31, and all the valves V31a are closed in the present embodiment. Moreover, the valve V31b is installed in the flow path of the water F31 that flows out after being heated by the first feed water heater 31, and all the valves V31b are closed.

  Further, the valve VB1a is installed in a flow path where the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1 flows to the first feed water heater 31 of the feed water heating unit 3, In the embodiment, all the valves VB1a are closed. Further, the valve VB31 is a drain water B31 (first drain water) that flows out after the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1 is cooled and condensed by the first feed water heater 31. The valve VB31 is all closed.

  Thereby, in this embodiment, the water F311 which flowed out from the deaerator 311 branches to the 2nd feed water heater 32, and does not flow in. For this reason, in this embodiment, the total amount of water F311 flowing out from the deaerator 311 flows to the second solar heater 5B as water F311B flowing into the second solar heater 5B (that is, F311B = F311). ).

  The water F311B flowing into the second solar heater 5B is heated in the second solar heater 5B. In this embodiment, the water F32 does not flow out from the second feed water heater 32. Further, the water F5b heated by the second solar heater 5B branches to the first feed water heater 31 and does not flow. For this reason, in this embodiment, the total amount of the water F5b flowing out from the second solar heater 5B flows to the first solar heater 5A as water F32B flowing into the first solar heater 5A (that is, F32B = F5b).

  The water F32B flowing into the first solar heater 5A is heated in the first solar heater 5A. Thereafter, the water F <b> 5 a heated by the first solar heater 5 </ b> A flows into the boiler 4. In the present embodiment, the water F31 does not flow out from the first feed water heater 31. For this reason, the water (F31 + F5a) which the water F31 which flowed out from the 1st feed water heater 31 and the water F5a which flowed out from the 1st solar-heater 5A merged does not flow into the boiler 4, but the 1st solar heat Only water F5 flowing out of the heater 5A flows into the boiler 4.

  Furthermore, in the present embodiment, the steam B1a (first extraction steam) does not flow out from the first extraction port A1a of the steam turbine 1 and does not flow into the first feed water heater 31. Further, the steam B1b (second extraction steam) does not flow out from the second extraction port A1b of the steam turbine 1 and does not flow into the second feed water heater 32.

  As described above, in addition to the plurality of valves V32a, V32b, V31a, V31b, VB1b, VB32, VB1a, and VB31 being fully closed, in this embodiment, the flow rate of the heat medium M5 is adjusted.

  Here, the second solar heater 5B heats the water F311B (= F311) with the same amount of heat as the amount of heat applied by the steam B1b (second extraction steam) flowing out from the second extraction port A1b. At the same time, the first solar heater 5A heats the water F32B (= F5b) with the same amount of heat as the amount of heat applied by the steam B1a (first extraction steam) flowing out from the first extraction port A1a. The flow rate of the heat medium M5 is adjusted. That is, after the valves V32a, V32b, V31a, V31b, VB1b, VB32, VB1a, VB31 are fully closed, the amount of heat applied to the water F5a flowing into the boiler 4 is the original state (that is, steam B1a, B1b The flow rate of the heat medium M5 is the same as (heated by the first extraction steam, the second extraction steam) and not heated by the first solar heater 5A and the second solar heater 5B) Adjustments are made.

  Thereby, the water F5a (boiler inflow water) which flows into the boiler 4 becomes the same temperature when it heats only using both the 1st feed water heater 31 and the 2nd feed water heater 32. FIG.

  Thus, in this embodiment, as in the case of the first embodiment, the temperature of the water F5a (boiler inflow water) flowing into the boiler 4 is the original state (ie, steam B1a, B1b (first extraction steam). , The second extraction steam), and the same as in the state where there is no heating by the first solar heater 5A and the second solar heater 5B), the heating amount heated by the boiler 4 is also the same. The amount of fuel (here, coal) consumed in the boiler 4 is the same. The output of the steam turbine 1 in the second operation increases more than the output in the first operation.

[C] Summary (effects, etc.)
As described above, in the steam turbine plant of the present embodiment, the first solar heater 5A and the second solar heater 5B are installed.

  The first feed water heater 31 is installed in parallel with the first solar heater 5A, and the second feed water heater 32 is installed in parallel with the second solar heater 5B. .

  That is, the first solar heater 5 </ b> A is extracted at the most upstream side in the steam turbine 1 among the plurality of feed water heaters (the first to fourth feed water heaters 31 to 34 and the deaerator 311). It is installed in parallel with the first feed water heater 31 through which the steam B1a (first extraction steam) flows. Then, in the second solar heater 5B, in the steam turbine 1, the steam B1b (second extracted steam) extracted on the upstream side next to the steam B1a (first extracted steam) flowing through the first feed water heater 31 is generated. It is installed in parallel with the second feed water heater 32 that circulates.

  About said steam turbine plant, as above-mentioned, the output of the steam turbine 1 can be increased, selecting several types of operation | movement with the amount of solar heat collection.

  For example, when the first operation is performed, the steam B1a (first extracted steam) extracted from the middle of the steam turbine 1 is circulated in the first feed water heater 31 as in the case of the first embodiment. Stop. Moreover, in the 1st feed water heater 31, the water F2 (here F32A) conveyed from the condenser 2 to the boiler 4 is stopped | circulated. On the other hand, in the 2nd feed water heater 32, the 3rd feed water heater 33, the 4th feed water heater 34, and the deaerator 311 except the 1st feed water heater 31, it is from the middle of the steam turbine 1. The extracted steam B1b, B1c, B1d, B1e (second to fifth extracted steam) is circulated. Moreover, in the 2nd feed water heater 32, the 3rd feed water heater 33, the 4th feed water heater 34, and the deaerator 311, the water F2 (here F2) conveyed from the condenser 2 to the boiler 4 is shown. , F34, F33, F311A). Further, in the second solar heater 5A and the first solar heater 5A, water F2 (here, F311B = F311) conveyed from the condenser 2 to the boiler 4 is circulated sequentially.

  And when it can receive more solar heat than the calorie | heat amount in which 1st driving | operation is possible and performs 2nd driving | running, in the 1st feed water heater 31, in the case of performing 1st driving | running, The steam B1a extracted from the middle of the turbine 1 is stopped from flowing. Moreover, in the 1st feed water heater 31, the water F2 (here F32A) conveyed from the condenser 2 to the boiler 4 is stopped | circulated. At the same time, unlike the case where the first operation is performed, the second feed water heater 32 stops the steam B1b (second extracted steam) extracted from the middle of the steam turbine 1 from flowing. Moreover, in the 2nd feed water heater 32, the water F2 (here F311A) conveyed from the condenser 2 to the boiler 4 stops flowing. On the other hand, in the 3rd feed water heater 33, the 4th feed water heater 34, and the deaerator 311 except the 1st feed water heater 31 and the 2nd feed water heater 32, in the middle of the steam turbine 1 The steam B1c, B1d, B1e (third to fifth extracted steam) extracted from is circulated. Moreover, in the 3rd feed water heater 33, the 4th feed water heater 34, and the deaerator 311, the water F2 (here F2, F34, F33) conveyed from the condenser 2 to the boiler 4 distribute | circulates. Let Further, in the second solar heater 5A and the first solar heater 5A, water F2 (here, F311B = F311) conveyed from the condenser 2 to the boiler 4 is circulated sequentially.

  In the operation method of the steam turbine plant of the present embodiment, in the first operation, the steam B1a (first extracted steam) does not flow into the first feed water heater 31 from the first extraction port A1a of the steam turbine 1. Further, in the second operation, the steam B 1 b (second extracted steam) does not flow into the second feed water heater 32 from the second extraction port A 1 b of the steam turbine 1. For this reason, in the present embodiment, in the steam turbine 1, the steam that flows out from the first extraction port A1a flows downstream from the first extraction port A1a. At the same time, in the present embodiment, in the steam turbine 1, the steam that flows out from the second extraction port A1b flows downstream from the second extraction port A1b. As a result, among the plurality of turbine stages, the steam flow rate increases in the turbine stage located downstream of the first extraction port A1a and the second extraction port A1b. Therefore, in this embodiment, the turbine output can be increased.

  In the steam turbine plant of the present embodiment, the heat received from the first solar heater 5A is received so that the amount of heat that heats the water F32B is greater than the amount of heat that heats the water F32A in the first feed water heater 31. There are cases where it can be done (for example, summer daytime). At the same time, the amount of heat of solar heat that is collected is originally higher than the amount of heat obtained by adding the amount of heat that heats the water F32A by the first feed water heater 31 and the amount of heat that heats the water F311A by the second feed water heater 31. There are many cases. In this case, since the temperature of the water F5a flowing into the boiler 4 can be increased, the amount of fuel (here, coal) consumed by the boiler 4 can be reduced. Therefore, not only can the amount of fuel consumed in the boiler 4 be increased by using a large amount of solar heat, but the output of the steam turbine 1 can be increased, and in some cases, the amount of fuel consumed in the boiler 4 And the output of the steam turbine 1 can be increased.

  If the first solar heater 5 </ b> A is not installed in the steam turbine plant, the water flowing into the boiler 4 unless the steam B <b> 1 a (first extraction steam) is circulated to the first feed water heater 31. The temperature of F5 decreases. Further, in the case where the second solar heater 5B is not installed in the steam turbine plant, if the steam B1b (second extracted steam) is not circulated to the second feed water heater 32, the water F5 flowing into the boiler 4 The temperature drops. For this reason, it is necessary to increase the heating amount in the boiler 4 by the reduced amount. As a result, even if the output increases, the turbine cycle efficiency decreases and the amount of fuel increases.

  In the operation method of the steam turbine plant of the present embodiment, the amount of power generation can be increased without increasing the amount of fuel consumed by the boiler 4 at the time when the demand for electric power is large, such as during the daytime in summer. In the present embodiment, the number can be increased as compared with the case of the first embodiment.

  In the present embodiment, in addition to performing a first operation for increasing the output without circulating the steam B1a (first extraction steam) flowing out from the first extraction port A1a of the steam turbine 1, The second operation of increasing the output without circulating the steam B1a (first extraction steam) flowing out from the first extraction port A1a and the steam B1b (second extraction steam) flowing out from the second extraction port A1b may be performed. it can. That is, the output increase amount can be adjusted.

[D] Modification [D-1] Modification 3-1
In this embodiment, it has two solar heaters (first solar heater 5A and second solar heater 5B), and the feed water heater 3 has five feed heaters (first to fourth feed water heating). Although the case where it has the devices 31-34 and the deaerator 311) is demonstrated, it is not restricted to this.

  This embodiment is applied when n feed water heaters are installed (n is a natural number of 1 or more) and m solar heaters are installed (m is a natural number from 1 to n). can do.

  In this case, the steam turbine 1 is provided with n extraction ports from which steam extracted from the middle of the steam turbine 1 flows out from the upstream side toward the downstream side.

  Each of the n feed water heaters (first to nth feed water heaters) is extracted steam (first to nth) extracted from each of the n extraction ports (first to nth extraction ports). Each of the extracted steam).

  Each of the n feed water heaters (first to nth feed water heaters) is installed in series in a flow path in which water F2 condensed in the condenser 2 is conveyed to the boiler 4 by the pump P2. The Here, the water F2 condensed in the condenser 2 is configured so as to flow through each of the n-th to first feed water heaters and be heated.

  Of the n feed water heaters, from each of the first to m th extraction ports located from the upstream side to the downstream side in the steam turbine 1 up to m-th (m is a natural number from 1 to n). Each of the first to m-th feed water heaters into which the extracted steam (first to m-th extracted steam) flows is installed in parallel to each of the first to m-th solar heaters.

  When operating this steam turbine plant, in each of the first to m-th feed water heaters, steam extracted from the middle of the steam turbine 1 (first to m-th extracted steam) and the condenser 2 Operation is performed by selecting whether or not to stop both the water F2 transported to the boiler 4 and the water F2 transported to flow.

  In this modification, the case where n is 5 and m is 2 corresponds to the third embodiment.

[D-1] Modification 3-2
The operation method of the steam turbine plant shown in the present embodiment may be applied to the case of the second prior art.

<Others>
Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Steam turbine, 2 ... Condenser, 3 ... Feed water heating part, 4 ... Boiler, 5 ... Solar heater, 5A ... 1st solar heater, 5B ... 2nd solar heater, 11 ... High pressure turbine, DESCRIPTION OF SYMBOLS 12 ... Medium pressure turbine, 13 ... Low pressure turbine, 31 ... 1st feed water heater, 32 ... 2nd feed water heater, 33 ... 3rd feed water heater, 34 ... 4th feed water heater, 51 ... Heat collector, 311 ... Deaerator, P2 ... Condensate pump, P311 ... Feed pump, P5 ... Heat medium pump

Claims (7)

A steam turbine;
A boiler for producing steam to flow into the steam turbine;
A condenser for cooling and liquefying the exhaust steam exhausted from the steam turbine;
A pump for conveying water liquefied by the condenser to the boiler;
Before the water conveyed from the condenser to the boiler by the pump flows into the boiler, a feed water heating unit that heats the water with extracted steam extracted from the middle of the steam turbine;
Before the water conveyed from the condenser to the boiler by the pump flows into the boiler, a solar heater that heats the water with a heat source derived from solar heat, and
In a flow path in which water liquefied by the condenser is conveyed to the boiler by the pump, operation is performed for a steam turbine plant in which the feed water heating unit includes a feed water heater installed in parallel to the solar heater. A driving method for performing
In the feed water heater installed in parallel with the solar heater, the extraction steam and the water conveyed from the condenser to the boiler by the pump are stopped from flowing, and the water is The steam turbine plant is operated by circulating all through a solar heater ,
A method for operating a steam turbine plant. When the heating amount by the solar heater is equal to or larger than the heating amount by the extraction steam in the feed water heater installed in parallel with the solar heater, the solar heater In the feed water heater installed in parallel, the bleed steam and the water transported from the condenser to the boiler by the pump are stopped from flowing.
The operating method of the steam turbine plant of Claim 1. The feed water heating unit has a plurality of feed water heaters,
Among the plurality of feed water heaters, a feed water heater through which the extracted steam extracted at the most upstream side in the steam turbine circulates is installed in parallel to the solar heater,
The operating method of the steam turbine plant of Claim 1. The feed water heating unit has a plurality of feed water heaters,
Among the plurality of feed water heaters, a first feed water heater through which a first extracted steam extracted at the most upstream side in the steam turbine flows, and an extraction at the upstream side next to the first extracted steam in the steam turbine. Both the second feed water heater through which the second extracted steam is circulated are installed in parallel to the solar heater,
When operating the steam turbine plant,
In the first feed water heater, the first extraction steam and the water conveyed from the condenser to the boiler by the pump are stopped from flowing,
In the second feed water heater, the second extraction steam and the water conveyed from the condenser to the boiler by the pump are stopped from flowing.
The operating method of the steam turbine plant of Claim 1. The feed water heating unit has a plurality of feed water heaters,
As the solar heater, a first solar heater and a second solar heater are installed,
Among the plurality of feed water heaters, a first feed water heater through which the first extracted steam extracted at the most upstream side in the steam turbine flows is installed in parallel to the first solar heater. ,
Of the plurality of feed water heaters, a second feed water heater through which a second extracted steam extracted upstream of the first extracted steam in the steam turbine flows is connected to the second solar heater. Installed in parallel,
When operating the steam turbine plant,
In the first feed water heater, a first operation for stopping both the first extraction steam and the water conveyed from the condenser to the boiler by the pump;
In the first feed water heater, the first extraction steam and the water conveyed from the condenser to the boiler by the pump are stopped from flowing, and in the second feed water heater, The second operation is performed by stopping both the second extraction steam and the water conveyed from the condenser to the boiler by the pump, and the second operation is performed.
The operating method of the steam turbine plant of Claim 1. The feed water heating unit has n (n is a natural number of 1 or more) feed water heaters,
The steam turbine is provided with n extraction ports from which the extraction steam flows out from the upstream side toward the downstream side,
Each of the n feed water heaters is configured such that each of the extraction steam extracted from each of the n extraction ports flows.
Of the n feed water heaters, the first of which the extracted steam flows from each of the extraction ports located up to the m-th (m is a natural number from 1 to n) from the upstream side to the downstream side in the steam turbine. To m-th feedwater heaters are installed in parallel to the solar heater,
When operating the steam turbine plant,
In each of the first to m-th feed water heaters, both the extracted steam and the water conveyed from the condenser to the boiler by the pump are stopped from flowing.
The operating method of the steam turbine plant of Claim 1. The feed water heating unit has n (n is a natural number of 1 or more) feed water heaters,
The steam turbine is provided with n extraction ports from which the extraction steam flows out from the upstream side toward the downstream side,
Each of the n feed water heaters is configured such that each of the extraction steam extracted from each of the n extraction ports flows.
The solar heaters are installed m (m is a natural number from 1 to n),
Among the n water heaters, each of the first to m-th water heaters into which the extracted steam flows from each of the extraction ports located from the upstream side to the downstream side in the steam turbine from the m-th side Are installed in parallel to each of the first to m-th solar heaters,
When operating the steam turbine plant,
In each of the first to m-th feed water heaters, select whether to stop the circulation of both the extracted steam and the water conveyed from the condenser to the boiler by the pump. Characterized by driving,
The operating method of the steam turbine plant of Claim 1.

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