JPWO2010086897A1 - Steam-utilizing plant, operation method of the plant, steam supply device, and steam supply method - Google Patents

Abstract

The thermal power plant includes a steam generator such as a boiler, a high-pressure turbine, a low-pressure turbine, a condenser, a low-pressure feed water heater, and a steam heat pump device. Steam generated in the boiler is supplied to a high-pressure turbine and a low-pressure turbine and condensed in a condenser. The feed water discharged from the condenser is heated by the extracted steam from the low-pressure turbine in the low-pressure feed water heater. Further, this water supply is heated by a steam heat pump device located downstream and supplied to the boiler. The steam heat pump apparatus includes a plurality of compressors and a condenser provided for each compressor and provided with a heat transfer tube therein. The steam extracted from the low-pressure turbine is supplied to each compressor in order and compressed, and the temperature rises. A part of the steam discharged from the upstream compressor is condensed by the feed water flowing in the heat transfer pipe in the condenser and guided to the downstream compressor. The feed water flowing through the heat transfer tube is heated by steam.

Description

  The present invention relates to a steam-utilizing plant, a method for operating the plant, a steam supply device, and a steam supply method, and more particularly, a plant using steam suitable for application to a thermal power plant and a nuclear power plant and the plant. The present invention relates to an operation method, a steam supply device, and a steam supply method.

  External heat engines such as thermal power plants and nuclear power plants are based on Rankine cycle. The Rankine cycle is a cycle in which condensable vapor is used as a working medium, and consists of the following four processes. (1) Heat feed water to generate hot water. (2) The hot water is further heated to generate steam. (3) The steam is sent to the turbine and expanded to obtain power. (4) Condensate steam to supply water. In a normal power plant, these four processes are assigned to each device as follows. In the power plant, (1) and (2) are responsible for boilers and steam generators such as nuclear reactors for boiling water nuclear power plants, (3) for steam turbines, and (4) for condensers. The working medium is circulated constantly.

  As a method for improving the efficiency of the Rankine cycle, a regeneration process is usually used. In the regeneration process, heating of the feed water in the process (1) is performed using steam extracted from the turbine, and heat is recovered by extraction from the turbine. Although the turbine output decreases with the bleed air, the recovered heat is effectively used for heating the feed water, so that the thermal efficiency is improved. Moreover, in order to suppress the wetness in a turbine, the reheating process which reheats a steam in the middle of expansion | swelling of the steam in process (3) is normally used. As an additional effect, thermal efficiency and power are increased.

  A steam engine that realizes a more efficient Carnot cycle with condensable steam as a working medium is the Iwanami Lecture, Basic Engineering 8 Thermodynamics III, pp. 231 to 252 (Take Ono, Iwanami Shoten, (1971) (Issued on May 7)) (in particular, see pages 234 to 236, FIG. 6.3). In this steam engine, instead of the Rankine cycle process (1), hot water is generated by compressing feed water generated by condensation of steam and uncondensed steam together. This process is called a compression liquefaction process.

  Among the conventional techniques described above, in the regeneration process, the maximum thermal efficiency can be theoretically obtained by making the bleed points of the steam from the turbine into continuous bleeds innumerably. However, in practice, the steam extraction point must be finite, and there remains room for improving the thermal efficiency in the regeneration process.

  Japanese Patent Laying-Open No. 2008-2413 describes an example of a steam heat pump system in FIG. This steam heat pump includes an evaporator, a plurality of compressors, and a plurality of cooling towers. The plurality of compressors are connected in series with each other by connecting a steam inlet of a compressor located downstream to a steam outlet of the compressor located upstream. Each cooling tower is disposed between the compressors. The steam generated in the evaporator is compressed by the most upstream compressor, the temperature rises, and is cooled by the cooling tower. The steam cooled in the cooling tower is compressed by another compressor located downstream, the temperature rises, and is supplied to the other cooling tower to be cooled. Thus, in the steam heat pump, the compression of the steam by the compressor and the cooling of the compressed steam by the cooling tower are repeated.

  Japanese Patent Application Laid-Open No. 5-65808 describes a co-heated steam turbine plant. This co-heat steam turbine plant supplies steam generated in a boiler to a turbine, rotates a generator to generate electric power, and uses steam exhausted from the turbine as a high-pressure process steam supply destination and a low-pressure process steam supply destination. Supply each. The steam supplied to the high pressure process steam supply destination compresses the steam exhausted from the turbine with a compressor.

  In Japanese Utility Model Laid-Open No. 1-123001, steam supplied from a condenser is compressed by a single compressor, and the compressed steam is supplied to four water heaters from a plurality of locations in the axial direction of the compressor. The thermal power plant to be described is described.

JP 2008-2413 A JP-A-5-65808 Japanese Utility Model Publication No. 1-123001 Iwanami Lecture Fundamental Engineering 8 Thermodynamics III, pages 231 to 252 (Hiroshi Ono, Iwanami Shoten (issued January 7, 1971))

  In the compression liquefaction process, the theoretical maximum thermal efficiency may be obtained. However, it is a gas in the steam engine that realizes the Carnot cycle described in Thermodynamics III, pages 234 to 236 and Fig. 6.3 (Shu Ono, Iwanami Shoten, published on January 7, 1971). Compressed in a mixed state of steam and liquid feed water. When compression is performed in such a state where the gas and the liquid are mixed, the density ratio of the gas and the liquid is large, the uniformity of the density is not maintained, and the compression efficiency is lowered. In the steam engine described in FIG. 6.3, it is necessary to compress the mixed steam and feed water at a high pressure ratio in order to obtain hot water only by the compression liquefaction process. For this reason, a cylinder type compressor is used in the steam engine. This compresses only one of the reciprocating motions of the piston in the cylinder, so that a steady operation is impossible due to pulsation. In addition, it is difficult to increase the capacity of the cylinder type, and it is difficult to apply to a commercial power plant in terms of capacity.

  Japanese Patent Laid-Open No. 2008-2413 only describes that the steam whose temperature is increased by compressing the steam with a plurality of compressors is supplied to the customer, and the temperature of the liquid supplied to the steam generator is increased. It does not mention that. The water sprayed on the compressed steam is only used for cooling the compressed steam.

  Japanese Laid-Open Patent Publication No. 5-65808 describes that steam exhausted from a turbine is compressed by a compressor and supplied to a high-pressure process steam supply destination. Japanese Patent Laid-Open No. 5-65808 does not mention increasing the temperature of the liquid supplied to the steam generator.

Japanese Utility Model Laid-Open No. 1-123001 discloses a technical idea of heating a feed water by compressing a part of steam generated in a thermal power plant. On the other hand, Japanese Utility Model Laid-Open No. 1-112301 does not mention any technical idea of Carnot cycle of a plant using steam such as a thermal power plant. The inventors examined this technical idea in detail. The result of this examination will be described below.
FIG. 3 of Japanese Utility Model Laid-Open No. 1-123001 is a state diagram of the thermal cycle, and represents enthalpy and entropy in each part of the thermal power plant. According to this state diagram, the steam in the condenser is compressed by the steam compressor on the saturation line up to the fourth stage feed water heater. On the other hand, steam extracted from a plurality of intermediate stages of the steam compressor is supplied to separate feed water heaters, and the feed water is heated along the saturation line by the feed water heaters.
However, vapor compression using a vapor compressor is an isentropic change even in an ideal case assuming no loss. That is, thermodynamically, it is required that entropy is constant and enthalpy increases. In Japanese Utility Model Laid-Open No. 1-123001, in the process of compressing steam, a part of the water supply is sprayed in the form of a mist in the steam compressor to reduce the entropy of the steam. It is difficult to spray mist in the middle of a paragraph (rotating part) of the steam compressor because it causes a reduction in the thickness of the steam compressor. In Japanese Utility Model Laid-Open No. 1-123001, when the steam that has flowed into the condenser is supplied by the steam compressor, mist contained in the steam supplied to the steam compressor is removed. In consideration of the description in Japanese Utility Model Laid-Open No. 1-123001, the position where the water supply can be sprayed in the form of a mist is such as the outlets of a plurality of steam compressors connected in series in the steam compression process. Limited to stationary parts. Therefore, in the state diagram of FIG. 3, the change in enthalpy relative to entropy is such that, for each stage of the steam compressor, the enthalpy once rises isoentropically, and the enthalpy returns to its saturation line by spraying mist. Should be indicated by a zigzag line.

  On the other hand, in Japanese Utility Model Laid-Open No. 1-123001, the state is changed along the saturation line in the steam compressor. This is based on the assumption that the number of stages is sufficiently large and the zigzag line is substantially close to the saturation line. It is thought that there is. Moreover, while the number of stages of the steam compressor is sufficiently large, the extraction to the feed water heater is four stages, and the number of both stages does not match. For this reason, it reflects the technical concept of the Carnot cycle of the steam engine in Non-Patent Document 1 described above, that is, the technical concept of realizing the Carnot cycle by compressing gas steam and liquid feed water in a mixed state. Not.

  Such a thermal power generation plant described in Japanese Utility Model Laid-Open No. 1-123001 is not a plant aimed at bringing it closer to the Carnot cycle. The inventors thought to engineer a plant using steam that is closer to the Carnot cycle.

  The objective of this invention is providing the plant using the steam which can improve the thermal efficiency of a plant, the operating method of the plant, a steam supply apparatus, and a steam supply method.

A feature of the present invention that achieves the above-described object is that a condensate of steam used in a steam utilization device to which steam discharged from the steam generation device is supplied and supplied with a liquid supplied to the steam generation device. Equipped with a liquid heating device that uses heated steam
The liquid heating device is provided with a plurality of stages of compressors arranged so as to compress the steam in order, and a pair is formed for each of the compressors of the plurality of stages. A plurality of steam cooling devices for heating the liquid supplied and supplied to the steam generating device by the steam;
Except for the steam cooling device to which the compressed steam is supplied from the final stage compressor, the steam cooling device connected to one compressor located upstream is connected to the other one located downstream of this compressor. The compressor is connected to supply cooled steam.

  According to the present invention, the steam whose temperature has been increased by being compressed by the compressor (first compressor) is guided to the steam cooling device (first steam cooling device), and the compressed steam whose temperature has increased. Is used to heat the liquid supplied to the steam generator. The steam cooled by the steam cooling device (first steam cooling device) is supplied to another compressor (second compressor) located downstream and compressed again. The steam compressed by the compressor (second compressor) is supplied to another steam cooling device (second steam cooling device) located downstream, and the steam cooling device (first steam cooling device) located upstream is used. The heated liquid can be further heated to increase the temperature of the liquid. On the other hand, steam that has been cooled by a certain steam cooling device (first steam cooling device) and whose temperature has decreased is supplied to another compressor (second compressor) located downstream, so that the steam in the other compressor The compression ratio can be increased, and the steam temperature can be further increased accordingly.

  That is, according to the present invention, in each steam cooling device paired with each compressor, the liquid supplied to the steam generating device is heated using the steam compressed by each compressor, and a certain compressor is used. Since the steam cooled by the connected steam cooler is supplied to other compressors located downstream, in each steam cooler connected to each stage compressor and receiving steam supply, The difference between the temperature and the temperature of the liquid heated by this vapor is reduced, and it is thermally equivalent to a state where the vapor and the liquid are mixed. Therefore, the present invention reflects the technical idea of Carnot cycle, in which the vapor and the liquid heated thereby are compressed in a mixed state. From these, a plant using steam that is closer to the Carnot cycle from the Rankine cycle is engineered. For this reason, the temperature of the liquid supplied to a steam generator using the compressed steam which rose to a higher temperature can be made higher. The amount of heat generated in the steam generator can be effectively used for the generation of steam by the increase in the temperature of the liquid, and the thermal efficiency of the plant using steam can be improved.

Using either the extracted steam extracted from the turbine to which the steam discharged from the steam generator is supplied or the partial exhaust steam exhausted from the turbine, the exhaust steam discharged from the turbine is condensed. A liquid heating device for heating the liquid generated and supplied to the steam generator,
The liquid heating device is provided with a plurality of stages of compressors arranged to sequentially compress one of the extracted steam and the exhaust steam, and a pair is formed for each of the plurality of stages of compressors. A plurality of steam cooling devices that are supplied with steam compressed by the formed compressor and heat liquid supplied to the steam generating device by the steam;
Except for the steam cooling device to which the compressed steam is supplied from the final stage compressor, the steam cooling device connected to one compressor located upstream is connected to the other one located downstream of this compressor. The above-described object of the present invention can also be achieved by a steam-utilizing plant connected to the compressor to supply cooled steam.

  According to the present invention, the thermal efficiency of a plant using steam can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the thermal power plant of Example 1 of the plant using the steam which is one suitable Example of this invention. It is a block diagram of the vapor | steam heat pump apparatus shown in FIG. FIG. 2 is a temperature (T) -entropy (S) diagram of the thermal power plant shown in FIG. 1. It is explanatory drawing which shows the improvement of the thermal efficiency in the thermal power plant using a steam heat pump apparatus, (A) is a TS diagram of the thermal power plant which heats feed water using extracted steam, (B) is extracted steam. FIG. 2C is a Tq · S diagram of a thermal power plant that uses and heats feed water, and FIG. 3C is a Tq · S diagram of a thermal power plant that heats feed water using a steam heat pump device. It is a block diagram of the conventional thermal power plant. FIG. 6 is a temperature (T) -entropy (S) diagram of the conventional thermal power plant shown in FIG. 5. It is a block diagram of the thermal power plant of Example 2 of the plant using the steam which is the other Example of this invention. It is a temperature-entropy diagram of the thermal power plant shown in FIG. It is a block diagram of the thermal power plant of Example 3 of the plant using the steam which is the other Example of this invention. FIG. 10 is a temperature-entropy diagram of the thermal power plant shown in FIG. 9. It is a block diagram of the thermal power plant of Example 4 of the plant using the steam which is the other Example of this invention. It is a temperature-entropy diagram of the thermal power plant shown in FIG. It is a block diagram of the boiling water nuclear power plant of Example 5 of the plant using the steam which is the other Example of this invention. It is a block diagram of the pressurized water nuclear power plant of Example 6 of the plant using the steam which is the other Example of this invention. It is a block diagram of the food processing plant of Example 6 of the plant using the steam which is the other Example of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1B, 1C, 1D ... Thermal power plant, 2 ... Boiler, 2A ... Supercritical pressure boiler, 3 ... High pressure turbine, 4 ... Low pressure turbine, 7 ... Condenser, 8 ... Low pressure feed water heater, 10 ... Feed water piping 11, 11A, 11B ... steam heat pump, 12A, 12B, 12C, 12D ... compressor, 15 ... motor, 16A, 16B, 16C, 16D ... condenser, 17A, 17B, 17C, 17D ... heat transfer tubes, 18A, 18B , 18C ... moisture separator, 21A, 21B, 21C, 21D ... pump, 22A, 22B, 22C, 22D ... condensate water pipe, 23, 24, 31 ... bleed pipe, 30 ... high pressure feed water heater, 35 ... boiling water Type nuclear power plant, 36, 39 ... reactor, 37, 37A ... core, 38 ... pressurized water nuclear power plant, 41 ... steam generator.

  The inventors solved the problem in the steam engine that realizes the Carnot cycle described in Fig. 6.3 on page 235 of Thermodynamics III (Hiroshi Ono, Iwanami Shoten (issued January 7, 1971)). The plant configuration that can make the plant of the ranking cycle closer to the Carnot cycle was examined. In the course of this study, the inventors compressed the steam with a compressor in a state where the steam and the feed water supplied to the steam generator are separated, and heated the feed water using the steam that has been compressed and increased in temperature. I found a new technical idea. The present invention has been made by applying this technical idea.

  An example of equipment to which the new technical idea found by the inventors is applied will be described below.

  A typical example is a plant using a steam generator such as a power plant (such as a thermal power plant and a nuclear power plant) and a turbine. In this plant, steam supplied from the steam generator to the turbine is extracted from the turbine or the exhaust of the turbine, and the extracted steam is sequentially compressed by a plurality of stages of compressors, and compressed by the compressors of each stage to increase the temperature. The rising steam is supplied to each steam cooling device forming a pair for each of the compressors in a plurality of stages, and the feed water of the plant supplied to the steam generating device is heated by these steam cooling devices. Furthermore, the steam cooled by the steam cooling device to which steam is supplied from the compressor located upstream is supplied to one compressor located downstream of the compressor.

  The heated water supply is generated by condensing steam exhausted from the turbine. A plurality of compressors are provided to supply steam sequentially from upstream to downstream to each stage compressor, and in each steam cooling device, the feed water is heated by each steam exhausted from each compressor, and this feed water is heated. In some cases, when steam cooled by a steam cooling device is supplied to a downstream compressor, the greater the number of compressor stages and the number of steam cooling devices, the closer the cycle of the plant is to the Carnot cycle.

  The new technical idea found by the inventors has led to a new concept of the steam heat pump. In this steam heat pump, steam is compressed by a multi-stage compressor, and heated water is heated in each steam cooling device by the steam that has been compressed and the temperature is increased, so that hot water supply can be obtained. .

  An embodiment of the present invention to which the above-described new technical idea is applied will be described below.

  A plant that uses the steam of Example 1, which is a preferred embodiment of the present invention, will be described with reference to FIGS. The plant using steam of the present embodiment is a thermal power plant 1 which is a thermal power plant. The thermal power plant 1 includes a boiler 2 which is a steam generator, a high pressure turbine (first turbine) 3, a low pressure turbine (second turbine) 4 having a lower pressure than the high pressure turbine 3, a condenser 7, and a low pressure feed water heater 8. And a vapor heat pump device (liquid heating device) 11. The boiler 2 is connected to the high-pressure turbine 3 and the low-pressure turbine 4 by a main steam pipe 6. A reheater 5 is provided in the main steam pipe 6 between the high pressure turbine 3 and the low pressure turbine 4. A water supply pipe 10 connects the condenser 7 and the boiler 2. The water supply pipe 10 is provided with a condensate pump 9A, a low-pressure feed water heater 8, a feed water pump 9B, and a steam heat pump device 11 in this order from upstream to downstream. The extraction pipe 23 is connected to a turbine casing (not shown) of the low-pressure turbine 4 and further connected to the low-pressure feed water heater 8.

  As shown in FIG. 2, the steam heat pump device 11 includes compressors 12A, 12B, 12C and 12D, a motor (drive device) 15, condensers 16A, 16B, 16C and 16D, and moisture separators 18A, 18B and 18C. Have. The compressors 12A, 12B, 12C, and 12D are turbo compressors that are rotating compressors having rotating blades. Rotors (not shown) having moving blades of the compressors 12 </ b> A, 12 </ b> B, 12 </ b> C and 12 </ b> D are connected to the rotating shaft 13. The rotating shaft 13 is connected to a motor 15 via a gear 14.

  The condenser 16A is connected to the first stage compressor 12A by an exhaust pipe 19A. The condenser 16A is connected to the second stage compressor 12B by a supply pipe 20A. A moisture separator 18A is provided in the supply pipe 20A. The condenser 16B is connected to the compressor 12B by an exhaust pipe 19B. The condenser 16B is connected to the third stage compressor 12C by a supply pipe 20B. A moisture separator 18B is provided in the supply pipe 20B. The condenser 16C is connected to the compressor 12C by an exhaust pipe 19C. The condenser 16C is connected to the fourth stage compressor 12D, which is the final stage, by a supply pipe 20C. A moisture separator 18C is provided in the supply pipe 20C. The condenser 16D is connected to the compressor 12D by an exhaust pipe 19D. In the steam heat pump device 11, a compressor and a condenser are provided in pairs. The first-stage compressor 12 </ b> A located at the most upstream is connected to the turbine casing of the low-pressure turbine 4 by an extraction pipe 24 provided with an on-off valve 25. The extraction pipe 24 is connected to the same position as the position where the extraction pipe 23 is connected to the low-pressure turbine 4 in the axial direction of the low-pressure turbine 4. The connection position of the extraction pipe 24 to the low pressure turbine 4 is shifted in the circumferential direction of the low pressure turbine 4 from the connection position of the extraction pipe 23 to the low pressure turbine 4. The bleed pipe 24 may be connected to the bleed pipe 23.

  A heat transfer tube 17A is provided in the condenser 16A, and a heat transfer tube 17B is provided in the condenser 16B. A heat transfer tube 17C is provided in the condenser 16C, and a heat transfer tube 17D is provided in the condenser 16D. The water supply pipe 10 is connected to the inlet of the heat transfer pipe 17A downstream of the water supply pump 9B. The water supply pipe 10 connects the outlet of the heat transfer tube 17A and the inlet of the heat transfer tube 17B, the outlet of the heat transfer tube 17B and the inlet of the heat transfer tube 17C, and the outlet of the heat transfer tube 17C and the heat transfer tube 17D, respectively. Further, the water supply pipe 10 connects the outlet of the heat transfer pipe 17D and the boiler 2. The condensers 16 </ b> A, 16 </ b> B, 16 </ b> C, and 16 </ b> D are condensers when focusing on the steam exhausted from each compressor, but are heaters when focusing on the water supplied through the water supply pipe 10.

  A condensed water pipe 22A provided with a pump 21A is connected to the bottom of the condenser 16A. A condensed water pipe 22B provided with a pump 21B is connected to the bottom of the condenser 16B. A condensed water pipe 22C provided with a pump 21C is connected to the bottom of the condenser 16C. A condensed water pipe 22D provided with a pump 21D is connected to the bottom of the condenser 16D. The condensed water pipes 22A, 22B, 22C and 22D are connected to the condensed water pipe 22D downstream of the pump 21D. Although not shown, the condensed water pipe 22D is connected to the water supply pipe 10 existing between the outlet of the heat transfer pipe 17D and the boiler 2.

  The thermal power plant 1 includes a steam supply device. The steam supply device includes a boiler 2, a steam heat pump device 11, and a water supply pipe 10. The high-pressure turbine 3 and the low-pressure turbine 4 are steam utilization devices.

  In FIG. 1, alphabets a, b, d to h, and g ′ representing the thermodynamic state of steam are attached to typical connection points in the thermal power plant 1.

  The steam generated in the boiler 2 is supplied to the high-pressure turbine 3 through the main steam pipe 6 and further guided to the reheater 5 and the low-pressure turbine 4. In the reheater 5, the steam discharged from the high pressure turbine 3 is heated by the superheated steam discharged from the superheater (not shown) of the boiler 2. Steam whose temperature has risen in the reheater 5 is supplied to the low-pressure turbine 4. The steam supplied to the high-pressure turbine 3 and the low-pressure turbine 4 rotates the high-pressure turbine 3 and the low-pressure turbine 4 whose rotation shafts are connected to each other. A generator (not shown) connected to the rotating shafts of these turbines rotates to generate power.

  The steam exhausted from the low-pressure turbine 4 is condensed by the condenser 7 to become water. This water is supplied to the boiler 2 through the water supply pipe 10 as water supply. The feed water discharged from the condenser 7 is boosted by the condensate pump 9A and supplied to the low-pressure feed water heater 8. Steam extracted from the low-pressure turbine 4 is supplied to the low-pressure feed water heater 8 through the extraction pipe 23. The feed water supplied to the low-pressure feed water heater 8 is heated by the steam supplied through the extraction pipe 23, and the temperature of the feed water rises. The feed water discharged from the low-pressure feed water heater 8 is boosted by the feed water pump 9A, and supplied to the heat transfer tubes 17A, 17B, 17C and 17D of the condensers 16A, 16B, 16C and 16D by the feed water pipe 10. The feed water is heated by the heat held by the compressed steam while flowing through the heat transfer tubes 17A, 17B, 17C and 17D. The feed water discharged from the condenser 16D is supplied to the boiler 2 through the feed water pipe 10.

  The heating of the feed water by the steam heat pump device 11 will be described in detail. In each of the compressors 12 </ b> A, 12 </ b> B, 12 </ b> C, and 12 </ b> D, a rotor having moving blades is rotated by driving the motor 15. The steam extracted from the low-pressure turbine 4 is supplied to the first stage compressor 12 </ b> A through the extraction pipe 24. At this time, the on-off valve 25 is open. The steam is compressed by the compressor 12A and the temperature rises. The compressed steam is led into the condenser 16A through the exhaust pipe 19A, and is cooled by the feed water flowing in the heat transfer pipe 17A of the condenser 16A. By this cooling, a part of the vapor in the condenser 16A is condensed to become condensed water 26 and falls to the bottom of the condenser 16A. Since the steam supplied to the condenser 16A is higher than the temperature of the feed water flowing in the heat transfer tube 17A, it is condensed on the outer surface of the heat transfer tube 17A.

  The feed water supplied by the feed water pipe 10 and flowing in the heat transfer pipe 17A is heated by cooling the steam and condensing a part of the steam in the condenser 16A, and the temperature rises. The temperature of the steam in the condenser 16A and the temperature of the feed water in the heat transfer tube 17A are substantially equal, and the thermal equilibrium is approximately maintained between the steam and the feed water.

  The uncondensed vapor in the condenser 16A is guided to the compressor 12B through the supply pipe 20A after the moisture is removed by the moisture separator 18A. The volume flow rate of the steam supplied from the condenser 16A to the compressor 12B is reduced by cooling by the condenser 16A. The steam is compressed again by the compressor 12B, and the temperature rises. The temperature of the steam exhausted from the compressor 12B is higher than the temperature of the steam exhausted from the compressor 12A. The steam compressed by the compressor 12B is led into the condenser 16B through the exhaust pipe 19B, and is cooled by the feed water flowing in the heat transfer pipe 17B of the condenser 16B. By this cooling, a part of the vapor in the condenser 16B is condensed to become condensed water 26 and falls to the bottom of the condenser 16B. Since the steam supplied to the condenser 16B is higher than the temperature of the feed water flowing in the heat transfer tube 17B, it is condensed on the outer surface of the heat transfer tube 17B.

  The feed water discharged from the heat transfer tube 17A and flowing in the heat transfer tube 17B is heated by cooling the steam and condensing a part of the steam in the condenser 16B, and the temperature further rises. The temperature of the steam in the condenser 16B and the temperature of the feed water in the heat transfer tube 17B are approximately equal, and the thermal equilibrium is approximately maintained.

  The uncondensed vapor in the condenser 16B is guided to the compressor 12C through the supply pipe 20B after moisture is removed by the moisture separator 18B. The volume flow rate of the steam supplied from the condenser 16B to the compressor 12C is reduced by cooling by the condenser 16B. The steam is compressed again by the compressor 12C and the temperature rises. The temperature of the steam exhausted from the compressor 12C is higher than the temperature of the steam exhausted from the compressor 12B. The steam compressed by the compressor 12C is led into the condenser 16C through the exhaust pipe 19C, and is cooled by the feed water flowing in the heat transfer pipe 17C of the condenser 16C. By this cooling, a part of the vapor in the condenser 16C is condensed to become condensed water 26 and falls to the bottom of the condenser 16C. Since the steam supplied to the condenser 16C is higher than the temperature of the feed water flowing in the heat transfer tube 17C, it is condensed on the outer surface of the heat transfer tube 17C.

  The feed water discharged from the heat transfer tube 17B and flowing in the heat transfer tube 17C is heated by cooling the steam and condensing a part of the steam in the condenser 16C, and the temperature further rises. The temperature of the steam in the condenser 16C and the temperature of the feed water in the heat transfer tube 17C are substantially equal, and the thermal equilibrium is approximately maintained.

  The uncondensed vapor in the condenser 16C is guided to the compressor 12D through the supply pipe 20C after moisture is removed by the moisture separator 18C. The volume flow rate of the steam supplied from the condenser 16C to the compressor 12D is reduced by cooling by the condenser 16C. The steam is compressed again by the compressor 12D, and the temperature rises. The temperature of the steam exhausted from the compressor 12D is higher than the temperature of the steam exhausted from the compressor 12C. The steam compressed by the compressor 12D is led into the condenser 16D through the exhaust pipe 19D, and is cooled by the feed water flowing in the heat transfer pipe 17D of the condenser 16D. By this cooling, the vapor in the condenser 16D is condensed to become condensed water 26 and falls to the bottom of the condenser 16D. Since the vapor | steam supplied to the condenser 16D is higher than the temperature of the feed water which flows through the inside of the heat exchanger tube 17D, it is condensed on the outer surface of the heat exchanger tube 17D. All the vapor supplied in the condenser 16D is condensed in the condenser 16D.

  The feed water discharged from the heat transfer tube 17C and flowing in the heat transfer tube 17D is heated by condensing the vapor in the condenser 16D, and the temperature further rises. The temperature of the steam in the condenser 16D and the temperature of the feed water in the heat transfer tube 17D are substantially equal, and the thermal equilibrium is approximately maintained. The water supply discharged from the heat transfer tube 17D is guided to the boiler 2.

  Pumps 21A, 21B, 21C, and 21D are driven. The condensed water 26 accumulated at the bottom of the condenser 16A is boosted by the pump 21A and guided to the condensed water pipe 22D through the condensed water pipe 22A. The condensed water 26 accumulated at the bottom of the condenser 16B is boosted by the pump 21B and guided to the condensed water pipe 22D through the condensed water pipe 22B. The condensed water 26 accumulated at the bottom of the condenser 16C is boosted by the pump 21C and guided to the condensed water pipe 22D through the condensed water pipe 22C. The condensed water 26 accumulated at the bottom of the condenser 16D is boosted by the pump 21D, and supplied to the water supply pipe 10 through the condensed water pipe 22D and downstream of the condenser 16D. Each condensed water 26 from the condenser 16A, the condenser 16B, and the condenser 16C is also supplied into the water supply pipe 10 together with the condensed water 26 from the condenser 16D. For this reason, the condensed water discharged | emitted from each condenser is supplied to the boiler 2 with feed water.

  The advantages of this embodiment will be described in comparison with a conventional thermal power plant. As shown in FIG. 5, the conventional thermal power plant 1 </ b> A has a configuration in which the steam heat pump device 11 and the extraction pipe 24 are removed from the thermal power generation plant 1 of this embodiment, and a high-pressure feed water heater 30 and an extraction pipe 31 are added instead. have. The high pressure feed water heater 30 is provided in the feed water pipe 10 downstream of the low pressure feed water heater 8. The extraction pipe 31 connected to the high-pressure feed water heater 30 is connected to a turbine casing (not shown) of the high-pressure turbine 5. The steam extracted from the high-pressure turbine 5 is supplied to the high-pressure feed water heater 30 through the extraction pipe 31 and heats the feed water discharged from the low-pressure feed water heater 8. Also in FIG. 5, as in FIG. 1, alphabets a, b, d to h, and g ′ representing the thermodynamic state of steam are attached to typical connection points in the thermal power plant 1 </ b> A.

  FIG. 6 shows a temperature-entropy diagram of the thermal power plant 1A, a so-called TS diagram. In FIG. 6, the saturation line indicates the saturation temperature with respect to the entropy S. This TS diagram is written on the assumption that the steam generated in the boiler 2 is saturated steam below the critical temperature. Depending on the characteristics of the boiler 2, there is a case where the temperature is higher than that of the saturation line and the supercritical pressure is higher than that of the saturation line including the changing process.

  In the low-pressure feed water heater 8, the feed water is heated by the steam extracted from g of the low-pressure turbine 4, and the relationship between temperature and entropy changes from a to g '. By extracting the steam from g, the flow rate of the steam passing through the low-pressure turbine 4 between g and h decreases. The feed water is heated by the high pressure feed water heater 5 by the steam extracted from e of the high pressure turbine 3, and the relationship between temperature and entropy changes from g 'to b. Steam extraction from e to e 'reduces the steam flow at ef-g. A decrease in the flow rate of steam passing through the low-pressure turbine 4 results in a decrease in output. However, the heat discarded to the outside by the condensation of the steam in the condenser 7 is reduced, and the temperature of the steam supplied to the boiler 2 can be increased to the high temperature side g '. For this reason, the thermal efficiency of 1 A of thermal power plants improves rather than the case where there is no regeneration process.

  FIG. 3 shows a TS diagram for the thermal power plant 1 of the present embodiment. In the present embodiment, since the high-pressure feed water heater 30 is not provided, changes in e-b and g'-b shown in FIG. 5 do not occur. In this embodiment, by providing the steam heat pump device 11, the water supply in the state b is obtained using the water supply g 'and the extracted steam g having the same temperature. On the TS diagram of FIG. 3, the state of the water supply is changed from gb to b. At this time, it is not necessary to mix the steam and the feed water, and even if they are separated, it is equivalent to the mixed state if the steam and the feed water are in thermal equilibrium. In the present embodiment, the steam g supplied to the first stage compressor 12A of the steam heat pump device 11 is compressed using the four stage compressors 12A to 12D, and the feed water is heated by the condensers 16A to 16D. The feed water g ′ supplied to the heat transfer pipe 17A of the condenser 16A at the same temperature as the steam g supplied to the first stage compressor 12A can be changed to a feed water b having a temperature higher than the steam temperature of e. That is, the steam g having a lower temperature than the steam e is generated by using the steam heat pump device 1, and the steam having a higher temperature is generated from the steam e of the high-pressure turbine 3 in the conventional thermal power plant 1 </ b> A. Water supply b having a temperature higher than the temperature of the extracted steam can be generated. The feed water b having a high temperature supplied to the boiler 2 is heated to the saturated water c and then further heated to become saturated steam d. This eliminates the need for steam extraction from e of the high-pressure turbine 5 and increases the steam flow rate (e-f-g steam flow rate) from the reheater 5 to g of the low-pressure turbine 4. This increases the flow rate of the steam supplied to the low-pressure turbine 4 and increases the turbine output (machine output of the turbine). Further, the amount of steam supplied from the high-pressure turbine 3 to the reheater 5 increases, the amount of heat held by the steam heated by the reheater 5 and discharged from the reheater 5 also increases, and the turbine output Will be further enhanced. Since the feed water b supplied to the boiler 2 is higher than the steam e, the thermal efficiency of the thermal power plant 1 is improved more than that of the thermal power plant 1A.

  It will be qualitatively described with reference to FIG. 4 that the thermal efficiency of the thermal power plant 1 is improved by providing the steam heat pump device 11. FIG. 4A is a TS diagram for a conventional thermal power plant having a one-stage regeneration process. FIG. 4B is a Tq · S diagram for a conventional thermal power plant in which a one-stage regeneration process is realized by a feed water heater using extracted steam. In order to schematically consider that the flow rate of the steam flowing into the low-pressure turbine 4 is reduced by the steam extraction, the horizontal axis of FIG. 4B shows the product of the specific entropy and the steam flow rate. The temperature at each point on the horizontal axis is absolute zero. In FIG. 4B, AB (corresponding to g′-b in FIG. 6) indicates heating of the feed water by the feed water heater that supplies the extracted steam, and BC indicates heating of the feed water by the boiler. . Further, in FIG. 4B, the area of the polygon BCDG′I′B is the heat input to the thermal power plant (the output of the boiler 2), the area of the square AHH′A ′ is the exhaust heat of the thermal power plant, and the The area of the square ABCDEFHA represents the electrical output of the thermal power plant. The square FEGHF is a loss of electrical output of the thermal power plant due to steam extraction. On the other hand, the areas of the triangle ABI and the triangle HEG are theoretically equal. The area obtained by removing the triangle HFE from the area of the polygon IBCCDGI is equal to the area of the polygon ABCDEFHA and becomes the electrical output of the thermal power plant.

  FIG. 4C shows a Tq · S diagram for the thermal power plant corresponding to the present embodiment, in which the one-stage regeneration process of the thermal power plant is realized by the steam heat pump device 11. In FIG. 4C, IB (corresponding to gb-b in FIG. 3) indicates heating of the feed water by the steam heat pump device 11. In the thermal power plant using the steam heat pump device 11 in the regeneration process, the heat input is the same as in FIG. 4B, and the area of the polygon IBCCDGI is the electrical output of the thermal power plant. Therefore, in the thermal power plant using the steam heat pump device 11, the heat input is the same and the electrical output of the thermal power plant is increased by the area of the triangle HFE as compared with FIG. 4B. The efficiency of the target thermal power plant is improved over that of the target thermal power plant in FIG. 4B.

  A thermal power plant that realizes a one-stage regeneration process with a feed water heater to which extraction steam is supplied realizes a Rankine cycle, whereas a thermal power generation that realizes the regeneration process with a steam heat pump device 11 The plant generates a process IB and realizes a cycle approaching the Carnot cycle. By using the steam heat pump device 11, a larger amount of heat can be recovered with less power consumption in the motor 15, and the temperature of the feed water supplied to the boiler 2 is extracted from the high-pressure turbine 3 of the conventional thermal power plant 1A. The temperature can be increased. As a result, the thermal power plant 1 generates the process IB. Since the thermal power plant 1 according to the present embodiment realizes a cycle approaching the Carnot cycle, it is possible to increase the electrical output as compared with the thermal power plant 1A. As a result, the thermal efficiency of the thermal power plant 1 is improved over that of the thermal power plant 1A.

  In the present embodiment, the reason why a cycle approaching the Carnot cycle is realized will be described below. In the present embodiment, a plurality of stages of compressors and a plurality of condensers include a first stage compressor 12A and a condenser 16A connected thereto, a second stage compressor 12B and a condenser 16B connected thereto. A third stage compressor 12C and a condenser 16C connected thereto, and a final stage compressor 12D and a condenser 16D connected thereto are provided in pairs. Further, the steam cooled by the condenser 16A is supplied to the compressor 12B, the steam cooled by the condenser 16B is supplied to the compressor 12C, and the steam cooled by the condenser 16C is supplied to the compressor 12D. ing. In the condensers 16A, 16B, 16C, and 16D, heating of feed water and cooling of steam are performed. For this reason, in the condensers 16A, 16B, 16C and 16D, the difference between the temperature of the steam on the heating side and the temperature of the feed water on the heated side is reduced, and the thermally compressed steam and the feed water are mixed. A state equivalent to is realized in each condenser. Therefore, this embodiment reflects the technical idea of Carnot cycle, in which steam and feed water heated by this are compressed in a mixed state, and the thermal power plant 1 closer to the Carnot cycle is engineered from the Rankine cycle. Has been realized.

  By engineering the thermal power plant 1 that is closer to the Carnot cycle described above, the present embodiment provides the temperature of the liquid that is supplied to the steam generator by supplying the compressed steam that has risen to a higher temperature to each condenser. Can be made higher. The amount of heat generated in the steam generator can be effectively used for the generation of steam by the increase in the temperature of the liquid, and the thermal efficiency of the thermal power plant 1 can be improved.

  In this embodiment, since the feed water is heated by the steam heat pump device 11, the high-pressure feed water heater provided in the conventional thermal power plant becomes unnecessary.

  In this embodiment, using the feed water supplied to the boiler 2, each of the vapors discharged from the compressors 12 </ b> A, 12 </ b> B and 12 </ b> C and whose temperature has risen due to compression is cooled in the condensers 16 </ b> A, 16 </ b> B and 16 </ b> C. Therefore, the volumetric flow rate of the steam supplied to each compressor located downstream of these condensers can be reduced. For this reason, the compression efficiency of the vapor | steam in the compressor located downstream can be improved, and the temperature of the vapor | steam compressed with the compressor located downstream can also be made higher. Therefore, the temperature rise of the feed water for cooling the compressed steam is also increased. Accordingly, the electrical output of the thermal power plant 1 increases. Moreover, since the cooled steam is supplied to the compressor located downstream, the power for driving the compressor can be reduced. Providing a plurality of stages of compressors can reduce the pressure ratio between the inlet and outlet per stage of the compressor. For this reason, manufacture of a turbo compressor becomes easy. Since the compressors 12 </ b> A to 12 </ b> D compress steam that does not substantially contain water, the steam compression efficiency can be increased.

  In this embodiment, steam extracted from the low-pressure turbine 4, specifically, steam extracted from between the moving blades located upstream of the final stage moving blades in the low-pressure turbine 4 is supplied to the steam heat pump device 11. Therefore, the steam compression ratio in the steam heat pump device 11 can be reduced. For this reason, the number of stages of the compressor in the steam heat pump device 11 can be reduced, and the steam heat pump device 11 can be made compact.

  In the present embodiment, the steam extracted from the low-pressure turbine 4 is supplied to the steam heat pump device 11, so that the steam whose temperature has decreased due to work in the high-pressure turbine 3 and the low-pressure turbine 4 is supplied to the steam heat pump device 11. become. In the steam heat pump device 11, the extracted steam whose temperature has been lowered in this way is compressed by a plurality of compressors to increase the temperature of the steam, and the feed water supplied to the boiler 2 is heated by this steam, whereby conventional thermal power generation is performed. The feed water can be heated to a temperature higher than the temperature of the steam extracted from the high-pressure turbine 3 of the plant 1A. For this reason, the extraction pipe | tube 31 and the high voltage | pressure feed water heater 30 which were provided in the thermal power plant 1A become unnecessary. Therefore, in this embodiment, the amount of steam supplied to the reheater 5 increases, and the amount of heat held by the steam heated by the reheater 5 and discharged from the reheater 5 also increases. Accordingly, the amount of work performed by the steam discharged from the reheater 5 in the low-pressure turbine 4 also increases. As a result, the turbine output increases.

  By using the steam heat pump device 11, a larger amount of heat can be recovered with less power consumption in the motor 15, and the temperature of the feed water supplied to the boiler 2 is extracted from the high-pressure turbine 3 of the conventional thermal power plant 1A. The temperature can be increased. For this reason, it is possible to reduce the temperature of the seawater that is used for condensing steam discharged from the low-pressure turbine 4 in the condenser 7 and discharged to the sea, and the amount of heat discharged from the thermal power plant 1 to the outside is reduced. it can.

  Since the steam heat pump device 11 uses a plurality of compressors, the capacity of the compressor per stage is small, and the electric power consumed by the motor 15 can be reduced as compared with a large-sized single stage compressor.

  When the vapor | steam discharged | emitted from the compressor located upstream is supplied to a downstream compressor through a condenser, a vapor | steam passes a moisture separator. Since the droplets generated by the condensation of the vapor in the condenser are contained in the vapor supplied to the downstream compressor, the droplets are removed by the moisture separator, and the moving blades of the compressor located downstream are dropped. Damage, that is, erosion of the rotor blades can be prevented.

  A condenser to which steam discharged from a subsequent compressor is supplied has a higher internal pressure. In the present embodiment, a condensate water pipe having a pump is provided for each condenser, so that the condensate water 26 can be supplied from each condenser having a different internal pressure to the water supply pipe 10.

  In the present embodiment, in addition to the steam heat pump device 11 that heats the feed water, the low pressure feed water heater 8 that heats the feed water that is supplied with the steam extracted from the low pressure turbine 4 and flows through the feed water pipe 10 is provided. It is possible to reduce the temperature increase width of the water supply due to the heating in the device 11. For this reason, the number of stages of the compressor of the steam heat pump device 11 can be reduced, and the steam heat pump device 11 can be made compact. Such downsizing of the steam heat pump device 11 leads to downsizing of the thermal power plant.

  Since the condensed water of the steam generated in the condensers 16A to 16D is returned to the feed water flowing in the feed water pipe 10, the amount of heat released to the outside of the thermal power plant 1 is reduced, and the thermal efficiency of the thermal power plant 1 is further increased. improves.

  The compressor of the steam heat pump device 11 may be provided in five or more stages. The more compressor stages, the closer the cycle of the thermal power plant is to the Carnot cycle.

  The condensate water pipe 22D to which the condensate water pipes 22A to 22C are connected may be connected to the water supply pipe 10 upstream of the condenser 16A located most upstream.

  A plant using steam according to embodiment 2 which is another embodiment of the present invention will be described with reference to FIG. A thermal power plant 1B, which is a steam-using plant according to the present embodiment, replaces the boiler 2 with a supercritical pressure boiler 2A, which is a steam generator, in the thermal power plant 1 to extract the extracted steam from the high-pressure turbine 3. The high-pressure feed water heater 30 to which 31 is connected is provided in the feed water pipe 10 downstream of the low-pressure feed water heater 8, and the condensers 16 </ b> A to 16 </ b> D of the steam heat pump device 11 are arranged downstream of the high-pressure feed water heater 30. . The heat transfer tubes 17 </ b> A to 17 </ b> D in the condensers 16 </ b> A to 16 </ b> D are connected to the water supply pipe 10 in the same manner as the thermal power plant 1. The extraction pipe 24 connected to the first stage compressor 12 </ b> A of the steam heat pump device 11 is connected to the turbine casing of the high-pressure turbine 3.

  The thermal power plant 1 </ b> B includes a steam supply device having a supercritical pressure boiler 2 </ b> A, a steam heat pump device 11, and a feed water pipe 10.

  Steam generated in the supercritical boiler 2 </ b> A is supplied to the high-pressure turbine 3 and the low-pressure turbine 4. The feed water flowing through the feed water pipe 10 is heated by the extraction steam extracted from the low pressure turbine 4 and supplied to the low pressure feed water heating 8 through the extraction pipe 23. The feed water is further heated by the high pressure feed water heater 30 to which the extracted steam extracted from the high pressure turbine 3 is supplied. The steam extracted from the high-pressure turbine 3 is supplied to the compressor 12 </ b> A of the steam heat pump device 11 through the extraction pipe 24. The steam heat pump device 11 in the present embodiment also operates in the same manner as the steam heat pump device 11 in the first embodiment, and the feed water supplied to the supercritical pressure boiler 2A is heated by the condensers 16A to 16D.

  FIG. 8 shows a TS diagram for the thermal power plant 1B of the present embodiment. In the thermal power plant 1B, in the supercritical pressure boiler 2A, the steam is heated to a temperature in a state d where the temperature T is higher than the saturation line as shown in FIG. The temperature of the steam extracted from e of the high-pressure turbine 3 is a temperature on the saturation line, and the steam at this temperature is supplied to the compressor 12A.

  When the thermal power plant 1B is performing the rated load operation, the state of the water supply is changed from eb to b in a vertical state by heating the water supply with the steam heat pump device 11. Since such a state change is brought about, the cycle in the thermal power plant 1B approaches the Carnot cycle as in the first embodiment. For this reason, the electrical output of the thermal power plant 1B increases, and thermal efficiency improves.

  Another characteristic of the thermal power plant 1B using the supercritical pressure boiler 2A is that the transformer operation is normally performed during the partial load operation. This is performed to reduce the electrical output generated in the thermal power plant 1B when the power demand is low. At this time, based on the decrease in the heat output from the rated heat output of the supercritical pressure boiler 2A, the mass flow rates of the feed water and steam are reduced. The pressure and temperature of the steam generated in the supercritical pressure boiler 2 </ b> A are reduced so as to maintain the axial flow speed of the high-pressure turbine 3. Although the decrease in the steam temperature causes a decrease in the thermal efficiency of the external combustion engine, in the thermal power plant 1B, the loss of the high-pressure turbine 3 can be reduced, so that the overall thermal efficiency is increased.

  Since the thermal power plant 1B uses the steam heat pump device 11, even when the heat output of the supercritical pressure boiler 2A is reduced in the partial load operation, the generated steam amount can be maintained at the rated value. For this reason, it is not necessary to reduce the pressure and temperature of the steam generated in the supercritical pressure boiler 2A. Due to the function of the steam heat pump device 11, in the partial load operation, the ratio of the amount of steam supplied to the compressor 12A of the steam heat pump device 11 to the amount of water supplied to the heat transfer pipe 17A of the condenser 16A of the steam heat pump device 11 is set. It can be increased more than at the time of rated load operation, and the water supply at the temperature of state bp can be generated by changing from eb to the vertical state.

  The heat load obtained by the feed water from the supercritical pressure boiler 2A is proportional to the product of the change in entropy S and the temperature T. Since the change in entropy from state bq to state d during partial load operation is smaller than that from state b to state d during rated load operation, the thermal load that the water supply obtains during partial load operation is during rated load operation. Less than. As a result, the flow rate of the fluid circulating through the supercritical pressure boiler 2A, the high pressure turbine 3, the extraction pipe 24, the steam heat pump device 11, and the supercritical pressure boiler 2A is maintained, and the efficiency of the high pressure turbine 3 can be kept high. Moreover, the pressure and temperature of the steam generated in the supercritical pressure boiler 2A can be kept high, and the thermal efficiency of the thermal power plant 1B in the partial load operation can be kept high. This is realized by increasing the compression ratio of the steam in the steam heat pump device 11 in the partial load operation as compared with the rated load operation.

  In the present embodiment, in the rated load operation and the partial load operation, the temperature of the feed water supplied to the supercritical pressure boiler 2 </ b> A can be made higher than the steam temperature at the extraction point e of the high pressure turbine 3.

  A plant using steam of Example 3 which is another example of the present invention will be described with reference to FIG. The thermal power plant 1 </ b> C, which is a plant that uses steam of the present embodiment, installs a high-pressure feed water heater 30 in the feed water pipe 10 instead of the low-pressure feed water heater 8 in the thermal power plant 1, and compresses the steam heat pump device 11. The bleed pipe 24 connected to the machine 12 </ b> A is connected to the exhaust chamber connected to the condenser 7 of the low-pressure turbine 4. The condensers 16A to 16D of the steam heat pump device 11 are installed in the feed water pipe 10 between the condensate pump 9A and the feed water pump 9B. The high-pressure feed water heater 30 is disposed downstream of the feed water pump 9B.

  During operation of the thermal power plant 1 </ b> C, steam generated in the boiler 2 is supplied to the high pressure turbine 3 and the low pressure turbine 4. The steam extracted from the exhaust chamber of the low-pressure turbine 4 (steam before being exhausted from the low-pressure turbine 4 and cooled by the condenser 7) is supplied to the compressor 12A of the steam heat pump device 11 through the extraction pipe 24. Compressed sequentially with a stage compressor. The feed water discharged from the condenser 7 is heated by steam that has been compressed by the compressor and increased in temperature while flowing through the heat transfer pipes provided in the respective condensers. Thereafter, the feed water is supplied to the high-pressure feed water heater 30. Supplied. The feedwater that has reached the high-pressure feed water heater 30 is heated by steam extracted from the high-pressure turbine 3 and guided to the high-pressure feed water heater 30 through the extraction pipe 31. The feed water discharged from the high-pressure feed water heater 30 is supplied to the boiler 2.

  FIG. 10 shows a TS diagram for the thermal power plant 1C. Due to the heating of the feed water by the steam heat pump device 11, the state of the feed water changes to h-g0-g ', and the feed water temperature rises. g′-b indicates an increase in the feed water temperature due to heating in the high-pressure feed water heater 30.

  In the present embodiment, the cycle of the thermal power plant 1C can be brought close to the Carnot cycle by applying the steam heat pump device 11, and the output of the thermal power plant 1C can be increased. For this reason, the thermal efficiency of the thermal power plant 1C is improved. Since steam extraction from the low-pressure turbine 4 is not performed, the amount of steam flowing into the low-pressure turbine 4 is exhausted as it is from the final stage of the moving blade of the low-pressure turbine 4. The output of the low-pressure turbine 4 is improved, and the electrical output of the thermal power plant 1C is further increased.

  A plant using steam according to embodiment 4 which is another embodiment of the present invention will be described with reference to FIG. A thermal power plant 1D that is a plant using steam according to the present embodiment has a configuration in which the high-pressure feed water heater 30 and the extraction pipe 31 are removed from the thermal power plant 1C. Thermal power plant 1D does not install a low-pressure feed water heater and a high-pressure feed water heater, and heats the feed water to a set temperature by the steam heat pump device 11A. For this reason, in the steam heat pump device 11A, the number of stages of the compressor and the condenser is larger than the number of stages of the steam heat pump device 11 used in the first embodiment.

  FIG. 11 shows a TS diagram for the thermal power plant 1D. Due to the heating of the feed water by the steam heat pump device 11A, the state of the feed water changes to h-b0-g ', and the feed water temperature rises.

  Also in this embodiment, the cycle of the thermal power plant 1C can be brought close to the Carnot cycle by applying the steam heat pump device 11A. For this reason, a present Example can increase the electrical output of 1 C of thermal power plants, and can also improve the thermal efficiency. In the present embodiment, each effect produced in the first embodiment can be obtained. Furthermore, since steam is not extracted by the low-pressure turbine 4, the output of the low-pressure turbine 4 can be increased as in the third embodiment.

  A plant using steam of Example 5 which is another example of the present invention will be described with reference to FIG. Each of the embodiments described above is directed to a thermal power plant, but the plant using steam of this embodiment is a boiling water nuclear power plant (BWR plant) that is a nuclear power plant. The BWR plant 35 of the present embodiment has a configuration in which the boiler 2 in the thermal power plant 1 of the first embodiment is replaced with a nuclear reactor 36 that is a steam generator.

  The BWR plant 35 includes a steam supply device having a nuclear reactor 36, a steam heat pump device 11, and a water supply pipe 10.

  The nuclear reactor 36 includes a core 37 loaded with a plurality of fuel assemblies (not shown). Cooling water supplied to the reactor core is heated to heat by heat generated by nuclear fission of nuclear fuel material contained in the fuel assembly to become steam. This steam is supplied to the high-pressure turbine 3 and the low-pressure turbine 4 through the main steam pipe 6. The feed water discharged from the condenser 7 that condenses the steam discharged from the low-pressure turbine 4 is heated by the extracted steam extracted from the low-pressure turbine 4 by the low-pressure feed water heater 8. The steam extracted from the low-pressure turbine 4 is sequentially supplied to each compressor of the steam heat pump device 11 and is compressed by each compressor, and the temperature rises. The vapor | steam discharged | emitted from the compressor with the condenser provided for every compressor is cooled, and the feed water which flows through the inside of the heat exchanger tube in each condenser is heated like Example 1. FIG. The feed water heated by the steam heat pump device 11 is supplied to the reactor 36 which is a steam generator.

  Even in the present embodiment provided with the steam heat pump device 11, each effect produced in the thermal power plant 1 of the first embodiment can be obtained. The temperature of the feed water supplied to the nuclear reactor 36 is higher than the steam temperature at e of the high-pressure turbine 3.

  A plant using steam of Example 6 which is another example of the present invention will be described with reference to FIG. The plant using steam of the present embodiment is a pressurized water nuclear power plant (PWR plant) which is a nuclear power plant. The PWR plant 38 of the present embodiment has a configuration in which the boiler 2 in the thermal power plant 1 of the first embodiment is replaced with a steam generator (steam generator) 41 and a nuclear reactor 39 is further provided. The feed water pipe 10 is connected to an inlet of a heat transfer pipe provided in the steam generator 41, and the main steam pipe 6 is connected to an outlet of the heat transfer pipe. A nuclear reactor 39 having a core 37 </ b> A therein is connected to the trunk side of the steam generator 41 by a primary cooling pipe 40. A cooling water circulation loop is formed by the nuclear reactor 39, the primary cooling pipe 40 and the steam generator 41.

  The PWR plant 39 includes a steam supply device having a steam generator 41, a steam heat pump device 11, and a feed water pipe 10.

  The cooling water supplied to the core 37A is heated in the core 37A by heat generated by nuclear fission of nuclear fuel material. The high-temperature cooling water discharged from the core 37 </ b> A is supplied to the trunk side of the steam generator 41 through the primary cooling pipe 40 and returned to the reactor 39 through the primary cooling pipe 40. The feed water supplied from the feed water pipe 10 into the plurality of heat transfer pipes provided in the steam generator 41 is heated by the high-temperature cooling water supplied to the trunk side of the steam generator 41 to become steam.

  This steam is supplied to the high-pressure turbine 3 and the low-pressure turbine 4 through the main steam pipe 6. The feed water discharged from the condenser 7 that condenses the steam discharged from the low-pressure turbine 4 is heated by the extracted steam extracted from the low-pressure turbine 4 by the low-pressure feed water heater 8. The steam extracted from the low-pressure turbine 4 is sequentially supplied to each compressor of the steam heat pump device 11 and is compressed by each compressor, and the temperature rises. The vapor | steam discharged | emitted from the compressor with the condenser provided for every compressor is cooled, and the feed water which flows through the inside of the heat exchanger tube in each condenser is heated like Example 1. FIG. The feed water heated by the steam heat pump device 11 is supplied to the reactor 36 which is a steam generator.

  Even in the present embodiment provided with the steam heat pump device 11, each effect produced in the thermal power plant 1 of the first embodiment can be obtained. The temperature of the feed water supplied to the steam generator 41 is higher than the steam temperature at e of the high-pressure turbine 3.

  A plant using steam of Example 7 which is another example of the present invention will be described with reference to FIG. The plant using steam of this embodiment is a food processing plant 45. The food processing plant 45 includes a boiler 2 that is a steam generating device, a food processing device 46 that is a heat utilization device, an evaporator 47, a feed water pump 49, and a steam heat pump device 11. The steam supply pipe 50 connects the boiler 2 and the food processing apparatus 46. A steam discharge pipe 51 is connected to the food processing apparatus 46. A condensed water separator 48 is provided in the steam discharge pipe 51, and an evaporator 47 is provided in the steam discharge pipe 51 downstream of the condensed water separator 48. A water supply pipe 52 provided with a water supply pump 49 connects the condensed water separator 48 and the boiler 2. A steam heat pump device 11 is provided in the water supply pipe 52. The steam supply pipe 53 is connected to the evaporator 47 and further connected to the first stage compressor 12 </ b> A of the steam heat pump device 11. A water supply pipe 54 is connected to the evaporator 47.

  The water supply heated by the steam heat pump device 11 is supplied to the boiler 2 through the water supply pipe 52. The boiler 2 heats feed water and generates steam. This steam is discharged from the boiler 2 and supplied to the food processing apparatus 46 through the steam supply pipe 49. A raw material that is a raw material of the food to be manufactured is supplied into the food processing apparatus 46. This material is heated by the steam supplied in the food processing apparatus 46. Some foods use multiple materials. In this case, the material for each end product and the material obtained by mixing each other are heated separately in the food processing apparatus 46. The food processing apparatus 46 is provided with a plurality of steam heating apparatuses corresponding to the material to be heated. The food processing apparatus 46 further manufactures food using a plurality of materials thus heated.

  Part of the steam used to heat the material is condensed water. Steam containing condensed water is discharged from the food processing device 46 to the steam discharge pipe 51 and guided to the condensed water separation device 48. The condensed water separation device 48 separates condensed water from the steam containing condensed water discharged to the steam discharge pipe 51. The separated condensed water is supplied to the heat transfer tubes 17A to 17D of the condensers 16A to 16D of the steam heat pump device 11 through the water supply pipe 52 by driving the water supply pump 49.

  The remaining steam from which the condensed water has been separated by the condensed water separator 48 is supplied to the evaporator 47. The feed water supplied to the evaporator 54 by the feed water pipe 54 is heated by the steam supplied to the evaporator 47 to become steam. The steam supplied to the evaporator 54 and heating the feed water is discharged to the outside through the steam discharge pipe 51. The steam generated in the evaporator 47 is supplied to the first stage compressor 12 </ b> A through the steam supply pipe 53. The steam heat pump device 11 compresses steam by the compressors 12A, 12B, 12C, and 12D as in the first embodiment. The steam that has been compressed by each compressor and has risen in temperature is guided into each condenser provided for each compressor, and is cooled by feed water flowing through the heat transfer tubes 17A, 17B, 17C, and 17D. Conversely, the feed water is heated by steam and supplied to the boiler 2 through the feed water pipe 52. When the supply water supplied to the boiler 2 is not enough with the condensed water separated by the condensed water separator 48, the makeup water is supplied from the makeup water pipe 55 into the water supply pipe 52.

  Since the steam heat pump device 11 is used in this embodiment, the water supply temperature can be increased with less power consumption in the motor 15 as in the first embodiment. Since the temperature of the feed water supplied to the boiler 2 is further increased by the installation of the steam heat pump device 11, the heat generated in the boiler 2 can be effectively used for the generation of high-temperature steam in the present embodiment. For this reason, the thermal efficiency of the food processing plant 45 can be improved.

  The condensate separation device 48 can be provided for each necessary step in the food processing device 46.

  In the food processing plant 45, the evaporator 47 and the water supply pipe 54 may be removed, and the steam supply pipe 53 may be connected to the steam discharge pipe 51 downstream of the condensed water separator 48. In such a food processing plant, the evaporator 47 and the water supply pipe 54 are not required, so that the equipment is made compact. Furthermore, a part of the steam discharged from the food processing apparatus 46 to the steam discharge pipe 51 can be directly supplied to the compressor of the steam heat pump apparatus 11 through the steam supply pipe 53. For this reason, the thermal efficiency of the food processing plant 45 is further improved.

  The present embodiment can be applied to a cleaning plant and a chemical plant that use steam by replacing the food processing apparatus 46 with a steam cleaning apparatus and a chemical substance heating apparatus that are other heat utilization apparatuses. Each of the heat utilization devices described above is a steam utilization device because it utilizes the heat of steam.

INDUSTRIAL APPLICABILITY The present invention can be used for a plant that uses steam generated by a steam generator, for example, a thermal power plan and a nuclear power plant.

Claims (18)

A steam generating device that converts liquid into steam, a steam using device that is supplied with the steam discharged from the steam generating device, and a condensate of the steam that is used in the steam using device. A liquid heating device for heating the supplied liquid using the supplied vapor,
The liquid heating device is provided with a plurality of stages of compressors arranged so as to sequentially compress the steam, and a pair is formed for each of the plurality of stages of compressors, and is compressed by the compressors forming the pair. A plurality of steam cooling devices that are supplied with the steam and heat the liquid supplied to the steam generating device by the steam;
Except for the steam cooling device to which the steam compressed from the compressor at the final stage is supplied, the steam cooling device connected to the one compressor located upstream is located downstream of the compressor. A steam-utilizing plant, wherein the other steam is connected to supply the cooled steam.   Generated by the other steam generators in the first stage compressor of the liquid heating device, and other steam generators that generate steam by heating the liquid using the steam supplied to the steam utilization device The plant using steam according to claim 1, further comprising a steam supply pipe for supplying the steam.   The plant using steam according to claim 1, further comprising a steam supply pipe that supplies the steam supplied to the steam using device to the first stage compressor of the liquid heating device.   The plant using steam according to claim 3, wherein the steam using device is a turbine. Any one of a steam generator that converts liquid into steam, a turbine to which the steam discharged from the steam generator is supplied, extracted steam extracted from the turbine, and some exhaust steam exhausted from the turbine A liquid heating device that heats the liquid that is generated by condensing the exhaust steam discharged from the turbine and supplied to the steam generation device, using the steam of
The liquid heating device is provided with a plurality of stages of compressors arranged so as to sequentially compress any one of the extracted steam and the exhaust steam, and a pair is formed for each of the plurality of stages of compressors. A plurality of steam cooling devices that are supplied with the steam compressed by the paired compressors and heat the liquid supplied to the steam generating device by the steam;
Except for the steam cooling device to which the steam compressed from the compressor at the final stage is supplied, the steam cooling device connected to the one compressor located upstream is located downstream of the compressor. A steam-utilizing plant, wherein the other steam is connected to supply the cooled steam.   The plant using steam according to claim 5, wherein the liquid heating device includes a moisture separator that removes moisture contained in the steam that is discharged from the steam cooling device and supplied to the other compressor.   The plant using steam according to claim 5 or 6 provided with a feed water heater which heats said liquid with said extracted steam supplied.   The first turbine to which the steam discharged from the steam generator is supplied is provided, and the turbine is a second turbine to which the steam discharged from the first turbine is supplied. A plant that uses steam.   The plant using steam according to claim 8 provided with the feed water heater which heats said liquid with the steam extracted from said 1st turbine. A steam generator that converts liquid into steam; a first turbine that is supplied with the steam discharged from the steam generator; a second turbine that is supplied with the steam discharged from the first turbine; A liquid heating device that heats the liquid that is generated by condensing the steam discharged from the second turbine and supplied to the steam generation device using the steam extracted from one turbine;
The liquid heating device is provided with a plurality of stages of compressors arranged so as to sequentially compress any one of the extracted steam and the exhaust steam, and a pair is formed for each of the plurality of stages of compressors. A plurality of steam cooling devices that are supplied with the steam compressed by the paired compressors and heat the liquid supplied to the steam generating device by the steam;
Except for the steam cooling device to which the steam compressed from the compressor at the final stage is supplied, the steam cooling device connected to the one compressor located upstream is located downstream of the compressor. A steam-utilizing plant, wherein the other steam is connected to supply the cooled steam.   The plant using steam according to claim 10, wherein the steam generator is a supercritical steam generator.   The plant using steam according to claim 8 or 10, further comprising a reheat device that heats the steam exhausted from the first turbine and supplied to the second turbine. Steam is generated from the liquid supplied in the steam generator, the steam is supplied to the turbine, and one of the extracted steam extracted from the turbine and the partial exhaust steam exhausted from the turbine is used. Heating the liquid produced by condensing the exhaust steam discharged from the turbine and supplied to the steam generator;
Heating the liquid,
Compressing one of the extracted steam and the exhaust steam in order by a multi-stage compressor,
Supplying the steam compressed by the compressor forming a pair to each steam cooling device forming a pair for each of the compressors of the plurality of stages;
In each of the steam cooling devices, the liquid supplied to the steam generating device is heated by the compressed steam, and the steam cooling device to which the compressed steam is supplied from the final stage compressor is excluded. The steam exhausted from the steam cooling device connected to the one compressor located upstream is supplied to the other compressor located downstream of the compressor. A method of operating a plant that uses the characteristic steam. A liquid heating device that heats the liquid, and a steam generator that is supplied with the liquid heated by the liquid heating device and generates vapor of the liquid,
The liquid heating device is provided with a plurality of stages of compressors arranged so as to sequentially compress the vapor, and a pair is formed for each of the plurality of stages of compressors, and is compressed by the compressor forming the pair. And a plurality of steam cooling devices for heating the liquid supplied to the steam generator by the steam, and the compressed steam is supplied from the final stage compressor. Except for the steam cooling device, the steam cooling device connected to one of the compressors located on the upstream side sends the cooled steam to the other one compressor located on the downstream side of the compressor. A steam supply device connected to supply.   The steam supply apparatus according to claim 14, wherein the liquid heating apparatus includes a moisture separator that removes moisture contained in the steam that is discharged from the steam cooling apparatus and supplied to the other compressor. The steam is compressed in sequence by a multistage compressor,
Supplying the steam compressed by the compressor forming a pair to each steam cooling device forming a pair for each of the compressors of the plurality of stages;
In each of the steam cooling devices, the liquid supplied to the steam generating device is heated by the compressed steam,
Except for the steam cooling device to which the steam compressed from the compressor at the final stage is supplied, the steam exhausted from the steam cooling device connected to one compressor located upstream is A steam supply method comprising: supplying to one of the other compressors located downstream of the compressor; and supplying the heated liquid to a steam generator to generate a vapor of the liquid.   The steam supply method according to claim 16, wherein the steam compressed by the compressor is a part of the steam generated by the steam generator.   The steam supply method according to claim 16 or 17, wherein moisture contained in the steam discharged from the steam cooling device and supplied to the other compressor is removed.

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