JP5611019B2 - Shell plate heat exchanger and power plant equipped with the same - Google Patents

Description

  The present invention relates to a power plant, and more particularly to a shell-plate heat exchanger and a power plant including the same.

  There are several types of power plants. For example, a thermal power plant that generates steam with a boiler using fossil fuel, a nuclear power plant that uses a nuclear reactor, and uses heat generated by nuclear fission. Although these types of power plants can be further subdivided, in any case, the power generation efficiency of the entire power plant is increased by heating the feed water or the like using the extraction from the steam turbine.

  Since the present invention relates to a technique for efficiently performing heat exchange such as water supply in a power plant, the type of the power plant may be any of the above, but here, it is referred to as a boiling water light water reactor (hereinafter referred to as BWR). ) I will explain the case of a nuclear power plant.

  A conventional boiling water light water reactor (BWR) nuclear power plant boils water in a nuclear reactor containing a fissile material and supplies steam generated by the boiling to a high-pressure turbine and a low-pressure turbine through main steam pipes. The power is generated by rotating the generator linked to the main shaft.

  Steam that works in the turbine and is exhausted from the low-pressure turbine is condensed in the condenser to become water. This water is supplied again to the nuclear reactor through a water supply pipe as water supply. The feed water is boosted by a feed water pump provided in the feed water pipe and heated by six feed water heaters (four low pressure feed water heaters and two high pressure feed water heaters) provided in the feed water pipe to raise the temperature. Then, water is supplied into the reactor pressure vessel.

  In a boiling water nuclear power plant, the thermal power of the reactor is first determined, and the steam flow downstream from the reactor (steam in the main steam piping and turbine, etc.) is used so that the highest thermal efficiency can be obtained with this thermal power. )).

  Specifically, when the steam exhausted from the low-pressure turbine is condensed into water by a condenser, the latent heat of water cannot be used for power generation at normal reactor pressure (about 7 MPa) from the principle of thermal cycle. Therefore, it is discharged outside from the condenser and is wasted. Therefore, in order to improve the thermal efficiency of the boiling water nuclear power plant, a part of the steam is extracted from the high-pressure turbine and the low-pressure turbine and supplied to the high-pressure feed water heater and the low-pressure feed water heater. Heating feed water using extraction steam is performed. In this case, most of the heat possessed by the extracted steam is used for heating the feed water, so that most of the heat is recovered and the thermal efficiency of the boiling water nuclear power plant is improved.

  In general, in a boiling water light water reactor BWR using a recirculation system of a recirculation pump and a jet pump and equipped with a moisture separator MS, the steam generated in the reactor is finally changed from a low pressure turbine to a condenser. The amount of steam exhausted is about 2/3, and the remaining steam of about 1/3 is used for heating the feed water as extracted steam.

  In the improved boiling water light water reactor (ABWR) in which the moisture separator superheater MSH is installed instead of the moisture separator MS, the amount of steam finally sent from the low-pressure turbine outlet to the condenser is the main steam. Similar to BWR, it is about 2/3.

  In the boiling water nuclear power plants of Patent Document 1 and Patent Document 2, steam extracted from a high-pressure turbine or low-pressure turbine is supplied to a high-pressure or low-pressure feed water heater to heat the feed water. The high-pressure feed water heater and low-pressure feed water heater used here are generally shell and tube heat exchanger types, and a large number of U-shaped heat transfer tubes (tubes) are installed in the body (shell). Then, the temperature of the feed water rises due to heat exchange between the feed water flowing inside the heat transfer tube and the extracted steam flowing outside the heat transfer tube inside the fuselage. The steam extracted from the high-pressure turbine is supplied to the high-pressure feed water heater, and the steam extracted from the low-pressure turbine is supplied to the low-pressure feed water heater.

  The above-described measures for improving plant efficiency by heating feed water using extracted air are implemented in many power plants described above. Here, the feed water heater is a heat exchanger that performs heat exchange between extraction air and water supply, and is a heat exchanger that uses heating fluid as extraction air and heated fluid as supply water. This heat exchange with the water supply is intended to improve performance by regeneration efficiency.

  On the other hand, some power plants further exchange heat with the bleed air on the steam side. In the improved boiling water light water reactor (ABWR) in which the moisture separator superheater MSH is installed in place of the moisture separator MS, the moisture separator superheater MSH includes a moisture separator, and a downstream separator. It has a first stage superheater and a second stage superheater. The first stage superheater on the upstream side uses the steam extracted from the high-pressure turbine to superheat the steam from which moisture has been removed by the moisture separator. The downstream second stage superheater superheats the steam superheated by the first stage superheater using the steam extracted from the main steam pipe upstream from the high-pressure turbine. The main steam heated by the second stage superheater is supplied to the low pressure turbine.

  Here, the first-stage superheater and the second-stage superheater on the downstream side of the moisture separator are heat exchangers for exchanging heat between the extracted air and steam, and the heated fluid is used as the extracted air. It is a heat exchanger that uses heated fluid as steam. Thereby, it can be made still higher efficiency combined with the efficiency improvement by the heat exchange by the water supply side. This heat exchange with steam is intended to improve performance by reheat efficiency.

  Thus, in order to improve the thermal efficiency of the boiling water nuclear power plant of the boiling water light water reactor BWR or the improved boiling water light water reactor ABWR, the performance is improved by the regeneration efficiency by installing the feed water heater, and the humidity It is generally known that the moisture separation efficiency of the separation separator MS is improved, and further that the performance is improved by reheating efficiency by additionally installing a superheater in the moisture separator MS.

  However, the moisture separator superheater MSH has a first stage superheater and a second stage superheater that are composed of a moisture separator and a heat transfer tube in a large fuselage. It is difficult. Moreover, since the container of the conventional moisture separation superheater MSH is increased in size, there is also a problem for downsizing the entire building in which the moisture separation superheater MSH is installed.

  On the other hand, in order to simplify the power plant, Non-Patent Document 1 proposes an example of a power plant in which a multistage steam injector is applied instead of the conventional shell-and-tube heat exchange type water heater. Yes. The steam injector replaces a conventional water heater using a heat exchange system via a heat transfer tube, and exchanges heat by directly contacting the low-temperature water supply and the high-temperature extraction steam by removing the heat transfer tube.

  In this power plant, steam extracted from a high-pressure turbine or a low-pressure turbine is supplied to a multistage steam injector. In each steam injector, the feed water flows inside the diffuser shape, the steam flows from the nozzle installed in the throat portion of the diffuser at high speed, and the steam flows through the center of the feed water flow that has a conical outer periphery. The feed water is heated and accelerated while condensing the steam at the liquid interface and flows toward the next stage steam injector. On the other hand, it is also possible that the feed water flows through the central portion inside the diffuser shape and the feed water is accelerated while condensing the steam supplied from the outer peripheral portion.

  On the other hand, the plate-type heat exchanger proposed in Non-Patent Document 2 is used in the general industry especially for heat exchange between low-temperature and low-pressure fluids. A heat transfer promoting corrugated plate structure composed of a plurality of sheets is laminated with rubber packing, and is tightened with screws from both sides.

  A non-patent document 3 proposes a brazing plate type heat exchanger in which the use range is expanded for high temperature and high pressure. This is basically the same corrugated plate structure, but instead of rubber packing, each heat transfer plate is crimped by brazing to form an integral structure.

JP 2005-299644 A JP-A-7-189609

T. T. et al. Narabayashi, et al. , Proc. of ICONE-3, pp. 877-883, Kyoto, Japan, 1994 Plate heat exchanger, Hisaka Works Brazing plate heat exchanger, Nisaka Manufacturing Co., Ltd.

  As described above, various heat exchangers have been proposed in place of the conventional shell / tube heat exchange type. However, the conventional plate-type heat exchanger cannot be used for a power plant such as a nuclear power plant under the use conditions of temperature and pressure as it is. Moreover, although the existing brazing plate type heat exchanger is compact, it is difficult to use it for the moisture separation superheater MSH or the feed water heater because the amount of exchange heat is too small.

  Furthermore, according to the multistage steam injector described in Non-Patent Document 1, since the steam is condensed on the surface of the gas-liquid interface with the feed water, the flow is unstable due to the large volume change accompanying the condensation of the steam. There are concerns.

  In view of the above, the object of the present invention is to improve the performance of heat exchangers with condensation, such as feed water heaters and moisture separation superheaters, which are compact and can improve plant thermal efficiency. A heat exchanger and a power plant including the heat exchanger are provided.

  A feature of the present invention that achieves the above-described object is that a steam generator that introduces feed water to generate steam, a steam turbine that introduces steam from the steam generator to drive a generator, and is discharged from the steam turbine. The condenser that condenses the steam, and the condensate of the condenser is sent to the steam generator as feed water, and heat is exchanged using the feed water or steam as the heated fluid and the extraction from the steam turbine as the heating fluid In a power plant equipped with an exchanger, the heat exchanger fixes a unit in which heat transfer plates and pressure plates are alternately stacked in a pressure resistant shell, and covers each surface of the heat transfer plate sandwiched between the pressure resistant plates. This is achieved by forming a heating fluid channel and a heating fluid channel to exchange heat.

  Further, corrugated corrugated plates are formed in the flow paths on the respective surfaces of the heat transfer plate.

In addition, when a condensation phenomenon is caused by heat exchange in the heat exchanger, the flow path width of the corrugated plate of the heat transfer plate through which the fluid to be condensed passes is δ _v , and When the path width δ _f is set, the ratio of the channel widths of the corrugated plates is within a range satisfying the following relationship.
1 ≦ δ _v / δ _f ≦ 2
Further, the differential pressure ΔP between the two fluids that exchange heat in the heat transfer plate and the thickness t of the corrugated plate of the heat transfer plate are in a range that satisfies the following relationship.
1 × 10 ³ ≦ ΔP / t ≦ 1 × 10 ⁴ MPa / m
The pressure plate sandwiching the heat transfer plate has at least a quadrilateral frame of four sides as ribs, and at least one or more intermediate support ribs are installed in the inside thereof almost in parallel with the fluid flow.

  A feature of the present invention that achieves the above-described object is that a steam generator that introduces feed water to generate steam, a steam turbine that introduces steam from the steam generator to drive a generator, and is discharged from the steam turbine. A condenser for condensing the steam, a feed water heater for heating the condensate of the condenser, and a feed water heater in a power plant configured to send the feed water heated in the feed water heater to the steam generator Is a heat exchanger that performs heat exchange using the condensate from the condenser as the heated fluid and the extraction gas from the steam turbine as the heating fluid, and the heat exchanger includes a heat transfer plate and a heat transfer plate in the pressure-resistant shell. A unit in which the pressure plates are alternately stacked is fixed, and heat exchange is performed by forming a flow path of the heated fluid and a flow path of the heated fluid on each surface of the heat transfer plate sandwiched between the pressure plates.

  A plurality of feed water heaters are installed between the steam generator and the condenser, and at least one of the feed water heaters is a shell plate type heat exchanger.

  Moreover, the feed water heater comprised by the shell plate type heat exchanger installed the guide mechanism which fixes a unit in the inside, and enclosed the intermediate | middle medium between the inside of the shell and the said guide mechanism.

  A feature of the present invention that achieves the above-described object is that a steam generator that introduces feed water to generate steam, a steam turbine that introduces steam from the steam generator to drive a generator, and is discharged from the steam turbine. The condenser that condenses the steam and the condenser condensate is sent to the steam generator as feed water, and the steam turbine is composed of a high-pressure turbine and a low-pressure turbine. In a power plant that is introduced into a low-pressure turbine through a moisture separator superheater composed of a separator and a superheater, the superheater of the moisture separator superheater receives the steam discharged from the high-pressure turbine. A heat exchanger that performs heat exchange using the extraction fluid from the steam turbine as a heating fluid, and the heat exchanger fixes a unit in which heat transfer plates and pressure plates are alternately stacked in a pressure resistant shell. , A flow path of the heated fluid to each side of the sandwiched pressure plate heat transfer plates, forming a flow path of the heating fluid exchange heat.

  Further, the superheater of the moisture separation superheater is composed of a first stage superheater and a second stage superheater on the downstream side, and the first stage superheater is supplied with extraction air from a high-pressure steam turbine as a heating fluid. The second stage superheater is supplied with steam before flowing into the high-pressure steam turbine as a heating fluid.

  Also, a guide mechanism for fixing the unit was installed in the superheater installed in the moisture separation superheater, and an intermediate medium was sealed between the shell and the guide mechanism.

  A feature of the present invention that achieves the above-described object is that a steam generator that introduces feed water to generate steam, a steam turbine that introduces steam from the steam generator to drive a generator, and is discharged from the steam turbine. The condenser was discharged from the steam turbine in a condenser that cools the steam with seawater to condensate, and a power plant that sends the condenser condensate as feed water to the steam generator. A heat exchanger that performs heat exchange using steam as a heating fluid and seawater as a fluid to be heated, the heat exchanger fixing a unit in which heat transfer plates and pressure plates are alternately stacked in a pressure resistant shell, Heat exchange is performed by forming a flow path of the heated fluid and a flow path of the heated fluid on each surface of the heat transfer plate sandwiched between the pressure-resistant plates.

  A feature of the present invention that achieves the above object is a heat exchanger that performs heat exchange between a heated fluid and a heated fluid, and the heat exchanger includes a heat transfer plate and a pressure plate in a pressure resistant shell. The units stacked alternately are fixed, and heat exchange is performed by forming a flow path of the heated fluid and a flow path of the heated fluid on each surface of the heat transfer plate sandwiched between the pressure-resistant plates.

  Moreover, it is used as a heat exchanger of a residual heat removal system which is a heat removal operation mode of a dynamic low-pressure water injection system as a heat removal means of a nuclear power plant.

  Moreover, it is used as an emergency condenser which is a system for condensing steam by natural force without a driving source such as a pump as heat removal means of a nuclear power plant.

  Further, it is used as a heat exchanger for a static containment vessel cooling system, which is a system for condensing steam by natural force without a driving source such as a pump, as a heat removal means of a nuclear power plant.

  According to the present invention, in a nuclear power plant, compared to a conventional shell-and-tube heat exchanger, it becomes a high-performance heat exchanger with a low pressure loss, and it is possible to greatly reduce the size of the equipment.

The figure which shows the cross section of a shell plate type water supply heater. The figure which shows the cross section of the water chamber 52a of a shell plate type water supply heater. The figure which showed the flow A of the extraction air in the surface of the heat transfer plate 73 of 1 sheet. The figure which showed the flow B of the water supply in the back surface of the heat transfer plate 73 of 1 sheet. It is a figure which shows the structure of the power plant to which this invention is applied. The figure which shows the bird's-eye view of the heat-transfer plate layer by which the heat-transfer plate was laminated | stacked. The figure which shows the site | part in which 76 C of extraction flow paths are formed when it is set as the structure of FIG. 3a. The figure which shows the site | part in which the water supply flow path 79C is formed when it is set as the structure of FIG. 3a. The figure which shows an example of the surface shape for forming an extraction flow path in a heat-transfer plate. The figure which shows an example of the surface shape for forming a water supply flow path in a heat exchanger plate. The top view of a pressure-resistant plate with a rib for support. The figure which shows the AA sectional drawing of FIG. Sectional drawing of the flow path of a heat-transfer plate. Explanatory drawing which shows the temperature distribution of the conventional heat exchanger. Explanatory drawing which shows the temperature distribution of a shell plate type heat exchanger. The figure which shows the performance comparison of the conventional heat exchanger and a shell plate type heat exchanger. The figure which shows the example applied to the moisture separation superheater of a power plant. The schematic of the heat-transfer plate of Example 2 which is another Example of this invention. Schematic of the rib for support of Example 3 which is other examples of the present invention.

  There are four main methods for improving thermal efficiency in power plants. In a general Rankine cycle, wet steam exhausted by working in a high-pressure turbine is converted into superheated steam by a moisture separation superheater, and this superheated steam is supplied to a low-pressure turbine. The first method is application of a reheat cycle using this moisture separation superheater. The second method is application of a regeneration cycle in which steam extracted from the high-pressure turbine is supplied to the high-pressure feed water heater and steam extracted from the low-pressure turbine is supplied to the low-pressure feed water heater. The third method is to increase the main steam pressure and the main steam temperature, and the fourth method may be to increase the degree of vacuum in the condenser.

  The inventors pointed to effective use of main steam as one of these four measures to improve thermal efficiency in a power plant, because there are few significant changes in equipment in the power plant, and there are significant effects on improving thermal efficiency and electrical output. Squeezed. That is, the heat efficiency is improved by the regeneration cycle and the reheat cycle.

  Therefore, in order to improve the regeneration cycle, the steam extracted from each of the high-pressure turbine and the low-pressure turbine is optimized, the main steam flow rate is increased to increase the feed water temperature, and the feed water heater is improved in performance. It is possible to reduce this.

  In order to improve the reheat cycle, the amount of steam extracted from the main steam and high-pressure turbine is optimized, the main steam flow rate is increased to superheat the main steam temperature, and the high performance of the moisture separation superheater. Reduction of the bleed steam due to the conversion can be considered.

  As a result of these studies, the inventors have found that a feedwater heater and a moisture separator superheater are used to reduce the flow of extracted steam and increase the flow of main steam used to rotate the high and low pressure turbines. The conclusion was reached that it would be best to improve the performance of the heat exchanger. Also, by supplying the extracted steam from the high-pressure turbine and low-pressure turbine to the high-pressure feed water heater and low-pressure feed water heater, the exhaust heat released from the condenser to the sea can be reduced, and the steam generator (reactor) The heat generated by the steam generator and the boiler is effectively utilized in the power plant, so that the thermal efficiency of a power plant such as a boiling water nuclear power plant is improved.

  Thus, as a result of examining the measures for improving the thermal efficiency and electric output of the power plant, the inventors have made high performance heat exchangers such as a high pressure feed water heater, a low pressure feed water heater and a moisture separation superheater, Conclusion that even if the steam flow extracted from the high-pressure turbine and low-pressure turbine is small, the feed water temperature can be raised sufficiently, and the amount of main steam contributing to work in the high-pressure turbine and low-pressure turbine can be increased accordingly. Reached. That is, the increase in the amount of steam increases the amount of steam supplied to the high-pressure turbine and the low-pressure turbine, and the work of steam in each turbine increases.

  Therefore, as a result of further examination on this point, the conventional shell-and-tube type heat exchanger that exchanges heat through the heat transfer tube was changed to a shell-and-plate type heat exchanger through the heat transfer plate. The present inventors have found a new finding that heat exchangers such as a low-pressure feed water heater and a moisture separator superheater should be made compact.

  As a result, during operation of the power plant, the amount of main steam supplied from the reactor pressure vessel to the high-pressure turbine and low-pressure turbine is increased, and the flow rate of the extracted steam from the high-pressure turbine and low-pressure turbine is reduced, resulting in high-efficiency regeneration. A cycle power plant can be realized. As a result, both the thermal efficiency and electric output of the power plant can be improved.

  Moreover, you may use a shell plate type heat exchanger for a moisture separation superheater other than a feed water heater. As a result, during operation of the power plant, the amount of main steam supplied from the reactor pressure vessel to the high-pressure turbine and low-pressure turbine is similarly increased, and the flow rate of the extracted steam from the main steam piping and high-pressure turbine is reduced. An efficient reheat cycle power plant can be realized. As a result, it is possible to improve both the thermal efficiency and the electrical output of the power plant.

  Moreover, you may use a shell plate type heat exchanger for a condenser other than a feed water heater and a moisture separation superheater. Thereby, at the time of operation of a power plant, performance improvement of the condensation performance of a condenser is attained, and a high degree of vacuum can be realized. As a result, both the thermal efficiency and electric output of the power plant can be improved.

  Examples of the present invention reflecting the above examination results will be described below.

  A system configuration of a power plant according to embodiment 1 which is a preferred embodiment of the present invention will be described with reference to FIG. The power plant of the present embodiment is a boiling water nuclear power plant 1.

  A boiling water nuclear power plant 1 includes a reactor 2, which is a steam generator, a high pressure turbine 3, low pressure turbines 5A, 5B, and 5C, a main steam pipe 6, a condenser 11, a plurality of feed water heaters 16 and 17, and feed water. A pipe 15 and a moisture separation superheater 33 are provided.

  Among the heat exchangers to which the improvement according to the present invention is applied, the plurality of feed water heaters that are heat exchangers in the feed water system are the first high pressure feed water heater 16A, the second high pressure feed water heater 16B, and the third low pressure feed water heating. 17A, fourth low-pressure feed water heater 17B, fifth low-pressure feed water heater 17C, and sixth low-pressure feed water heater 17D. These feed water heaters are shell plate type feed water heaters. Each low-pressure feed water heater 17 is a feed water heater to which the extraction steam from the low-pressure turbine 5 is supplied via the extraction pipes 22, 23, 24, and 25. Each high-pressure feed water heater 16 is a feed water heater to which extracted steam from the main steam pipe 6 on the outlet side of the high-pressure turbine 3 or the high-pressure turbine 3 is supplied via the extracted pipes 20 and 21. In addition, 100 is the discharge system (drain piping) of the condensed water drain produced with the feed water heater.

  The high-pressure turbine 3 and the low-pressure turbines 5 </ b> A, 5 </ b> B, 5 </ b> C are connected to the nuclear reactor 2 by the main steam pipe 6. An isolation valve 7 and a main steam control valve 8 are installed in the main steam pipe 6 existing between the nuclear reactor 2 and the high-pressure turbine 3.

  Of the heat exchangers to which the improvement according to the present invention is applied, the moisture separation superheater 33 which is a heat exchanger in the steam system connects the high-pressure turbine 3 and the low-pressure turbines 5A, 5B and 5C. Installed. The moisture separator superheater 33 includes the moisture separator 4 and superheaters 34A and 34B. The moisture separator 4, the first stage superheater 34A, and the second stage superheater 34B are arranged in this order from upstream to downstream. These superheaters are shell plate superheaters. A steam pipe 38 connected to the main steam pipe 6 upstream of the main steam control valve 8 is connected to the second stage superheater 34B. A steam pipe 42 connected to the high-pressure turbine 3 is connected to the first stage superheater 34A. Reference numerals 26, 35, and 39 denote drain pipes for discharging the drain generated in the moisture separator 4 and the superheaters 34A and 34B.

  The high-pressure turbine 3 and the low-pressure turbines 5 </ b> A, 5 </ b> B, and 5 </ b> C are connected to each other by one rotating shaft 10 and further connected to the generator 9. In this embodiment, one high-pressure turbine and three low-pressure turbines are provided, but these numbers may be changed depending on the type of power plant.

  This embodiment has a main steam system and a water supply system. The main steam system includes a high pressure turbine 3, a moisture separation superheater 33, low pressure turbines 5 </ b> A, 5 </ b> B, 5 </ b> C, a main steam pipe 6, and a condenser 11. The feed water system includes a feed water pipe 15, a first high pressure feed water heater 16A, a second high pressure feed water heater 16B, a third low pressure feed water heater 17A, a fourth low pressure feed water heater 17B, a fifth low pressure feed water heater 17C, and a sixth. It has a low-pressure feed water heater 17D, a condensate pump 18 and a feed water pump 19.

  The condenser 11 is disposed below the low-pressure turbine 5 </ b> B, and is connected to the low-pressure turbine 5 </ b> B by a steam exhaust passage 37. The condenser 11 has a plurality of heat transfer tubes 12 disposed therein. These heat transfer pipes 12 are connected to a seawater supply pipe 13A and a seawater discharge pipe 13B. A seawater circulation pump 14 is installed in the seawater supply pipe 13A. The seawater supply pipe 13A and the seawater discharge pipe 13B extend to the sea.

  A water supply pipe 15 connects the condenser 11 and the reactor 2. The first high-pressure feed water heater 16A, the second high-pressure feed water heater 16B, the third low-pressure feed water heater 17A, the fourth low-pressure feed water heater 17B, the fifth low-pressure feed water heater 17C, and the sixth low-pressure feed water heater 17D From the furnace 2 toward the condenser 11, they are installed in the water supply pipe 15 in this order. A condensate pump 18 is provided in the feed water pipe 15 between the condenser 11 and the sixth low-pressure feed water heater 17D.

  The first high-pressure feed water heater 16A, the second high-pressure feed water heater 16B, the third low-pressure feed water heater 17A, the fourth low-pressure feed water heater 17B, the fifth low-pressure feed water heater 17C, and the sixth low-pressure feed water used in this embodiment. Each of the heaters 17D uses a feed water heater which is a shell plate type heat exchanger having a heat transfer plate, instead of a conventional feed water heater using a shell tube type heat exchanger having a heat transfer tube. .

  The detailed structure of the shell plate type heat exchanger having the heat transfer plate and the heat exchange principle will be described separately with reference to FIG. 3, and here, the simple structure of the feed water heater will be described.

  First, FIG. 1a shows a cross-sectional view of a shell plate type feed water heater. The feed water heater includes a water chamber 52a into which two fluids (feed water and bleed air) for heat exchange are introduced and discharged, and a body portion 50 for heat exchange between the fluids. The water chamber 52a is partitioned by a partition plate 53 and forms four chambers R1, R2, R3, and R4, as is apparent from FIG. In this figure, the right water chamber 52b is a region that does not particularly act for heat exchange.

  In the case of the first high-pressure feed water heater 16A, the extraction FA1 is introduced from the extraction pipe 20 into the chamber R1, and the extraction drain FA2 (condensed water) after heat exchange in the trunk portion 50 is performed via the chamber R2. It collects in the condensation pot 56 installed in the lower end part in the chamber 52a. After that, the condensed water is sequentially guided to the next stage feed water heater (in this case, the second high pressure feed water heater 16B) via the drain pipe 100. Since this drain still has a large amount of heat, it is mixed into the water injection of the feed water heater in the next stage to further recover the heat. The drain is finally led to the condenser 11. In the chamber R4, the feed water FB1, which is a fluid to be heated, is introduced from the feed water pipe 15, and the high temperature feed water FB2 after heat exchange in the trunk portion 50 is sent to the reactor 2 via the chamber R3.

  The water chamber 52 a and the body portion 50 are separated by a tube plate 51. A heat transfer plate layer 54 in which a large number of heat transfer plates 73 are laminated is fixed in the center portion by a heat transfer plate layer guide 54 b provided between the left and right tube plates 51 in the horizontal body portion 50. Yes. The extracted steam FA1 and the feed water FB1 exchange heat through a heat transfer plate layer 54 made of corrugated plates in a substantially complete counterflow. Note that high-temperature extraction steam acts as a heating fluid, and low-temperature water supply acts as a fluid to be heated. The extraction steam FA1 is deprived of heat along the flow direction to become condensed water FA2, and finally accumulates in the condensation pot 56. All the remaining feed water heaters other than the first high pressure feed water heater 16A have the same configuration as the first high pressure feed water heater 16A.

  FIG. 1C is a cross-sectional view of the body portion 50 and illustrates the flow A of bleed air on the surface of one heat transfer plate 73. As is clear from this figure, one heat transfer plate 73 is fixed to the central portion of the body 50 having a circular cross section by a heat transfer plate layer guide 54b. In addition, since the trunk | drum 50 is a cylinder and the heat-transfer plate 74 is a rectangle, the intermediate medium 55 can be enclosed between these via the heat-transfer plate layer guide 54b, and it can also improve heat exchange performance. It is.

  FIG. 1 d is a cross-sectional view of the body portion 50 and illustrates a flow B of water supply on the back surface of one heat transfer plate 73. As is clear by comparing FIG. 1C and FIG. 1d, heat extraction is performed by extracting air from the top to the bottom of the heat transfer plate 73 and supplying water from the bottom to the back of the heat transfer plate 73. Is going.

  Next, a specific connection relationship of the water supply system constituted by the water heater of the above configuration will be described from the downstream side (reactor 2 side) with reference to FIG. 1 (particularly FIG. 1b) and FIG. First, the water supply pipe 15 in the upper right of FIG. 1 b connected to the water chamber 52 a of the first high-pressure feed water heater 16 A is connected to the reactor 2. The first high-pressure feed water heating is such that the water supply pipe 15 at the upper right of FIG. 1b connected to the water chamber 52a of the second high-pressure feed water heater 16B is connected to the chamber R4 of the water chamber 52a of the first high-pressure feed water heater 16A. It is connected to the water chamber 52a of the vessel 16A. A feed water pipe 15 disposed between the second high-pressure feed water heater 16B and the third low-pressure feed water heater 17A; a feed water pipe 15 disposed between the third low-pressure feed water heater 17A and the fourth low-pressure feed water heater 17B; A feed water pipe 15 disposed between the fifth low pressure feed water heater 17C of the fourth low pressure feed water heater 17B and a feed water pipe 15 disposed between the fifth low pressure feed water heater 17C and the sixth low pressure feed water heater 17D are also provided. Similarly to the water supply pipe 15 arranged between the first high-pressure feed water heater 16A and the second high-pressure feed water heater 16B, the upper part of the water chamber 52a of the feed water heater located upstream, and the feed water heating located downstream Connected to the bottom of the water chamber 52a. In short, in FIG. 1b, these relations are such that the water supply from the upstream side is introduced into the chamber R4 of the water chamber 52a and sent from the chamber R3 of the water chamber 52a to the chamber R4 of the water heater on the downstream side, or in the final stage To connect to send to the furnace. In addition, the water supply piping 15 arrange | positioned between the 6th low-pressure feed water heater 17D and the condenser 11 of the most upstream is connected to chamber R4 in the water chamber 52 of the 6th low-pressure feed water heater 17D.

  The extraction pipe 20 connected to the high pressure turbine 3 at the extraction point of the high pressure turbine 3 is connected to the first high pressure feed water heater 16A. The extraction pipe 20 is installed at an extraction point located downstream of the first stage moving blade of the high-pressure turbine 3. Specifically, as shown in FIG. 1 b, the extraction pipe 20 is connected to the water chamber 52 of the first high-pressure feed water heater 16 </ b> A and flows out to the upstream side as condensed water. This opening of the bleed pipe 20 is preferably arranged at the upper part of the water chamber 52 in the case of a horizontal water heater. The drain pipe 35 connected to the superheater 34A and the drain pipe 39 connected to the superheater 34B are also connected to the upper part of the water chamber 52 of the first high-pressure feed water heater 16A, similarly to the extraction pipe 20. The connection position of the drain pipes 35 and 39 to the upper portion of the water chamber 52 exists above the upper end where the condensed water is accumulated and in the vicinity of the upper end.

  The extraction pipe 21 connected to the main steam pipe 6 existing between the high-pressure turbine 3 and the moisture separation superheater 33 is connected to the second high-pressure feed water heater 16B. The extraction pipe 21 may be connected to the high-pressure turbine 3 downstream from the moving blades at the final stage of the high-pressure turbine 3. The extraction pipe 22 connected to the low pressure turbine 5B at the most upstream extraction point (the first extraction point of the low pressure turbine) of the low pressure turbine 5B is connected to the third low pressure feed water heater 17A. A drain pipe 26 connected to the moisture separator 4 is connected to the third low-pressure feed water heater 17A. The extraction pipe 23 connected to the low pressure turbine 5B at the second extraction point (second extraction point of the low pressure turbine) from the upstream side of the low pressure turbine 5B is connected to the fourth low pressure feed water heater 17B. The extraction pipe 24 connected to the low pressure turbine 5B at the third extraction point (the third extraction point of the low pressure turbine) from the upstream of the low pressure turbine 5B is connected to the fifth low pressure feed water heater 17C. The extraction pipe 25 connected to the low pressure turbine 5B at the most downstream extraction point (fourth extraction point of the low pressure turbine) of the low pressure turbine 5B is connected to the sixth low pressure feed water heater 17D. The bleed pipes 21 and 22, the drain pipe 26, and the bleed pipes 23, 24, and 25 are connected to the corresponding water heater container in the same manner as the bleed pipe 20. The first, second, third, and fourth extraction points of the low-pressure turbine described above are positions of different stages of the plurality of stationary blades provided in the low-pressure turbine 5B, and the turbine casing (not shown) of the low-pressure turbine 5B. ).

  In FIG. 2, the low-pressure turbine 5B is large and the low-pressure turbines 5A and 5C are small, but the sizes of these low-pressure turbines are the same. Although not shown in figure, the condenser 11 is each provided also to the low pressure turbines 5A and 5C, and the water supply piping 15 is connected to each condenser 11, respectively. The feed water pipes 15 respectively connected to a total of three condensers 11 respectively provided corresponding to the low pressure turbines 5A, 5B and 5C are at a junction located upstream of the second high pressure feed water heater 16B. Merge and connect to the second high-pressure feed water heater 16B.

  Of the three water supply pipes 15 arranged in parallel for each of the low pressure turbines 5A, 5B, and 5C arranged upstream from the junction, the water supply pipes arranged corresponding to the low pressure turbines 5A and 5C, respectively. 15 includes a third low-pressure feed water heater 17A, a fourth low-pressure feed water heater 17B, a fifth low-pressure feed water heater 17C, a sixth low-pressure feed water heater 17D, and a condensate pump 18, which are low-pressure feed water heaters. They are installed in order from downstream to upstream. Therefore, corresponding to each of the low pressure turbines 5A and 5C, the third low pressure feed water heater 17A, the fourth low pressure feed water heater 17B, the fifth low pressure feed water heater 17C, the sixth low pressure feed water heater 17D, and the condensate Each of the water supply pipes 15 provided with the pumps 18 is disposed upstream of the above-described junction that exists upstream of the second high-pressure feed water heater 16B.

  Similarly to the low-pressure turbine 5B, the low-pressure turbines 5A and 5C are provided with first, second, third, and fourth extraction points. As with the low pressure turbine 5B, the extraction pipes 22, 23, 24, and 25 are connected to the first, second, third, and fourth extraction points of the low pressure turbine 5A. The extraction pipes 22, 23, 24, and 25 connected to the low-pressure turbine 5A are similar to the low-pressure turbine 5B in the third low-pressure feed water heater 17A and the fourth low-pressure feed water heating provided corresponding to the low-pressure turbine 5A. Connected to each container 28 of the vessel 17B, the fifth low-pressure feed water heater 17C, and the sixth low-pressure feed water heater 17D. Similarly to the low pressure turbine 5B, the extraction pipes 22, 23, 24 and 25 are connected to the first, second, third and fourth extraction points of the low pressure turbine 5C. The extraction pipes 22, 23, 24, and 25 connected to the low-pressure turbine 5C are similar to the low-pressure turbine 5B in the third low-pressure feed water heater 17A and the fourth low-pressure feed water heating provided corresponding to the low-pressure turbine 5C. Connected to each container of the vessel 17B, the fifth low-pressure feed water heater 17C, and the sixth low-pressure feed water heater 17D.

  Next, the operation state of the nuclear power plant configured as described above will be described. In the following description, the third low pressure feed water heater 17A, the fourth low pressure feed water heater 17B, the fifth low pressure feed water heater 17C and the sixth low pressure feed water heater 17D, the extraction pipes 22, 23, 24 and 25, and The first, second, third and fourth extraction points mean those provided for the low-pressure turbine 5B unless otherwise specified.

  For example, in the case of BWR, cooling water is supplied to the core (not shown) in the nuclear reactor 2 by a recirculation pump (not shown) and a jet pump (not shown). The cooling water is heated by heat generated by fission of nuclear fuel material contained in a plurality of fuel assemblies (not shown) loaded in the core, and a part of the cooling water becomes steam. The steam generated in the nuclear reactor 2 is supplied to the high-pressure turbine 3 and the low-pressure turbines 5A, 5B, and 5C through the main steam pipe 6.

  The steam discharged from the high-pressure turbine 3 is removed in the middle by the moisture separator 4 and superheated by the superheaters 34A and 34B. The superheater 34A overheats the steam from which moisture has been removed by the moisture separator 4 by supplying the steam extracted from the high-pressure turbine 3 to the superheater 34A through the steam pipe 42. The steam superheated by the superheater 34 </ b> A is supplied to the superheater 34 </ b> B through the steam pipe 38, which is extracted from the main steam pipe 6 upstream of the high-pressure turbine 3 and has a higher temperature than the steam flowing in the steam pipe 42. Is done by. The temperature of the steam superheated by the superheater 34B becomes higher than the temperature of the steam superheated by the superheater 34A. The steam exhausted from the superheater 34B is guided to the low pressure turbines 5A, 5B, and 5C, respectively.

  The moisture removed by the moisture separator 4 is drained into the drain pipe 26 and supplied to the third low-pressure feed water heater 17A. The extracted steam supplied to the superheater 34A through the steam pipe 42 is condensed by superheating the steam from which moisture has been removed by the moisture separator 4 in the superheater 34A. The saturated drain water generated by the condensation of the steam is supplied to the first high-pressure feed water heater 16A through the drain pipe 35. The extracted steam supplied to the superheater 34B through the steam pipe 38 is condensed by further superheating the steam superheated by the superheater 34A in the superheater 34B. The saturated drain water generated by the condensation of the steam is supplied to the first high-pressure feed water heater 16A through the drain pipe 39. The temperature of each saturated drain water flowing in the drain pipes 35 and 39 is substantially the same as the temperature of the extraction steam flowing in the extraction pipe 20.

  The pressure in the low pressure turbines 5 </ b> A, 5 </ b> B and 5 </ b> C is lower than the pressure in the high pressure turbine 3. The high-pressure turbine 3 and the low-pressure turbines 5A, 5B, and 5C are driven by steam and rotate the generator 9. Thereby, electric power is generated. The steam exhausted from the low-pressure turbines 5A, 5B and 5C is condensed in each condenser 11 to become water. That is, seawater is supplied into each heat transfer pipe 12 in each condenser 11 through the seawater supply pipe 13 </ b> A by driving the seawater circulation pump 14. The steam exhausted from the low-pressure turbines 5A, 5B and 5C is cooled and condensed by seawater flowing in the heat transfer pipes 12 in the condensers 11 provided separately corresponding to the respective steams. Due to the condensation of the steam, the temperature of the seawater flowing through each heat transfer tube 12 rises. Seawater discharged from each heat transfer tube 12 is discharged to the sea through the seawater discharge tube 13B.

  A condensate pump 18 and a feed pump 19 provided in each feed water pipe 15 separately connected to each condenser 11 are respectively driven. Condensed water generated in each condenser 11 is boosted by these pumps as feed water, passes through each feed water pipe 15, and is supplied between the third low-pressure feed water heater 17A and the second high-pressure feed water heater 16B. Or it joins the two water supply piping 15 and is supplied to the nuclear reactor 2. The feed water flowing in the three feed water pipes 15 is provided with a sixth low-pressure feed water heater 17D, a fifth low-pressure feed water heater 17C, a fourth low-pressure feed water heater 17B, and a third low-pressure feed provided corresponding to each low-pressure turbine. Heated sequentially by the feed water heater 17A. The feed water was provided in one or two feed water pipes 15 downstream from the junction of the three feed water pipes 15 existing between the third low pressure feed water heater 17A and the second high pressure feed water heater 16B. It is further heated by the second high-pressure feed water heater 16B and the first high-pressure feed water heater 16A to raise the temperature, and is supplied to the nuclear reactor 2 in a state where the set temperature is reached. Water supply pumps 19E and 19F are also driven.

  The feed water is heated by the extraction steam extracted from the fourth extraction point of the low pressure turbine 5B and supplied through the extraction pipe 25 in the sixth low pressure feed water heater 17D. The feed water heated by the sixth low-pressure feed water heater 17D is further heated by the extracted steam supplied from the third extraction point of the low-pressure turbine 5B and supplied through the extraction pipe 24 in the fifth low-pressure feed water heater 17C. The feed water heated by the fifth low-pressure feed water heater 17C is further heated by the extraction steam extracted from the second extraction point of the low-pressure turbine 5B and supplied through the extraction pipe 23 in the fourth low-pressure feed water heater 17B. The feed water heated by the fourth low-pressure feed water heater 17B is extracted from the first extraction point of the low-pressure turbine 5B and supplied through the extraction pipe 22 in the third low-pressure feed water heater 17A, and a moisture separator. 4 is further heated by saturated drain water discharged from 4 and supplied through drain pipe 26.

  The feed water heated by the third low-pressure feed water heater 17A is heated by the extraction steam that is extracted from the main steam pipe 6 and supplied through the extraction pipe 21 in the second high-pressure feed water heater 16B. The feed water heated by the second high-pressure feed water heater 16B is extracted from the extraction steam and superheater 34A extracted from the extraction point of the high-pressure turbine 3 and supplied through the extraction pipe 20 in the first high-pressure feed water heater 16A. The saturated drain water supplied through the drain pipe 35 and the saturated drain water discharged from the superheater 34B and supplied through the drain pipe 39 are heated. The temperature of the feed water supplied to the nuclear reactor 2 is increased by about 180 ° C. from the temperature of the feed water discharged from the condenser 11 due to heating by the six feed water heaters.

  The sixth low-pressure feed water heater 17D, the fifth low-pressure feed water heater 17C, the fourth low-pressure feed water heater 17B, and the third low-pressure feed water heater 17A provided corresponding to each of the low-pressure turbines 5A and 5C are also described above. The feed water flowing through each feed water pipe 15 is heated using each extraction steam.

  Next, a specific configuration of the heat transfer plate layer 54 shown in FIG. 1a will be described. FIG. 3a shows a bird's-eye view of the heat transfer plate layer 54 on which the heat transfer plate 73 of the first embodiment which is a preferred embodiment of the present invention is laminated. In this figure, an S plate 71 is installed at the left end and an E plate 72 is installed at the right end, and a plurality of heat transfer plates 73 are stacked therebetween. The heat transfer plate 73 constitutes one unit from several tens to several hundreds. Between the heat transfer plates 73, every other pressure-resistant plate 74 with support ribs is alternately sandwiched so as to withstand high pressure.

  Among these members, the S plate 71 at the left end is in contact with the left tube plate 51 of FIG. 1a and has holes 75, 77, 78, and 80 at the upper and lower left and right ends, respectively. The holes 75, 77, 78, and 80 communicate with the four chambers R1, R2, R3, and R4 divided by the water chamber 52a in FIG. Accordingly, the extracted steam FA1 flows into the body portion 50 from the inflow hole 75, and the drain FA2 flows out from the body portion 50 to the water chamber 52 through the outflow hole 77. Further, the feed water FB 1 flows into the body portion 50 from the inflow hole 78, and the high temperature water supply FB 2 flows out from the body portion 50 to the water chamber 52 through the outflow hole 80.

  The E plate 72 at the right end is in contact with the right tube plate 51 of FIG. 1a, but does not have holes 75, 77, 78, 80 at the upper and lower left and right ends. In contrast, a plurality of heat transfer plates 73 and support pressure plates 74 with ribs for support between the S plate 71 and the E plate 72 are provided with holes 75, 77, 78, 80 on the upper and lower ends of the S plate 71. A hole is provided at a position corresponding to.

  A plurality of heat transfer plates 73 and pressure-resistant plates 74 with support ribs are alternately arranged to form one system unit (heat transfer plate layer 54) of several tens to several hundreds. One unit 54a is formed by one heat transfer plate 73 and two pressure-resistant plates 74 with ribs for support arranged alternately.

  That is, as the heat transfer plate 1 unit 54a, the first one pressure-resistant plate 74 with a rib for support and the next one heat transfer plate 73 form an extraction flow path 76C between the holes 75 and 77. . Further, a water supply flow path 79C is formed between the holes 78 and 80 by the one heat transfer plate 73 and the next one pressure-resistant plate 74 with a rib for support. That is, by sandwiching one heat transfer plate 73 with two pressure-resistant plates 74 with support ribs, an extraction flow path 76C is formed on the surface of one heat transfer plate 73, and a water supply flow path 79C is formed on the back surface. Form. For this reason, the pressure-resistant plates 74 with support ribs and the heat transfer plates 73 that overlap each other are set in thickness and size so as to alternately form the above-described flow paths.

  FIG. 3b shows a portion where the extraction flow passage 76C is formed when the structure of FIG. 3a is formed, and FIG. 3C shows a portion where the water supply flow passage 79C is formed when the structure of FIG. 3a is formed. It is a thing. In short, when the extraction flow passage 76C is formed on one side of the heat transfer plate 73, the water supply flow passage 79C is formed on the opposite side, and the extraction flow passage 76C and the water supply flow passage 79C are formed. Are flowing in opposite directions.

  The support rib-attached pressure-resistant plate 74 has the purpose of defining the interval between the heat transfer plates 73 in order to form the above-described flow path. In addition to this purpose, in order to reduce the surface pressure by miniaturizing the thin plate so that the thin plate does not deform due to the differential pressure of the two fluids sandwiching the heat transfer plate 73, there is a center inside the frame other than the surrounding frame. At least one or more support ribs 74a are installed in the section. In addition, the direction of the rib is preferably substantially parallel to the fluid flow direction in order to reduce flow loss. The plurality of heat transfer plates 73 and the pressure-resistant plates 74 with ribs for support are alternately installed and sandwiched between the S plate 71 and the E plate 72 from both sides.

  If it is in a range that does not greatly deform like a buckling phenomenon, the length of the heat exchange element sandwiched between the S plate 71 and the E plate 72 may be about 2 to 3 m. Thus, the laminated structure as a heat exchange element is very simple. In addition, it is easy to disassemble, inspect, and clean by overhauling. Furthermore, when changing the heat exchange specification by changing the operating conditions etc. from the number of heat transfer areas determined in the initial design, if the number of pressure-resistant plates 74 with support ribs and heat transfer plates 73 is appropriately increased to the required number, Remodeling work becomes easy according to the change of exchange heat quantity.

  At this time, the following three types of methods for joining these many plates are conceivable. First, the pressure-resistant plate 74 with ribs for support is a material that is plastically deformed, and by tightening the S and E plates on both sides with a bolt or the like for sealing, the material itself deforms and seals. Next, the S and E plates, the heat transfer plate, and the entire pressure-resistant plate with ribs for support are heated to form a brazing method that melts at about 1000 ° C. Finally, there is a construction method in which these are welded joints instead of brazed joints.

  Next, how each fluid flows will be described. For example, when entering and exiting from the same S plate 71, the bleed air enters from the inflow hole 75 and exits from the outflow hole 77 at the lower left end. Water enters through the inflow hole 78 and exits through the outflow hole 80 at the upper right end. There are various combinations of flow directions depending on the holes formed on the heat transfer plate and the shape of the support rib 74a that controls the flow path, and the direction in which the ribs are stacked. Such a unit or stack may be used as one block, and the number of blocks required for heat exchange may be multi-layered.

  In the case of the feed water heater shown in FIG. 1, the structure in which extraction air and feed water are introduced into and discharged from one end of the feed water heater has been described. Needless to say, it can be arranged. For example, it may be introduced from the left water chamber 52a of FIG. Or extraction and water supply may flow in the reverse direction. In short, in the portion of the heat transfer plate layer 54, as long as the relationship between the extraction flow passage 76C and the water supply flow passage 79C formed on both surfaces of the heat transfer plate 73 as shown in FIG. However, the flow path may be formed in any way.

  FIG. 4 shows a schematic view of the heat transfer plate 73 of the first embodiment which is a preferred embodiment of the present invention. This is a view of one heat transfer plate 73 as viewed from the front. In the upper, lower, left and right corners of the heat transfer plate 73, bleed air inflow / outflow holes 75, 77 and feed water inflow / outflow holes 78, 80 are opened. As shown in FIGS. 3b and 3c, the heat transfer plate 73 forms an extraction channel 76C on one side and a water supply channel 79C on the other side.

  4A shows an example of a surface shape for forming the extraction flow passage 76C in the heat transfer plate 73, and FIG. 4B shows an example of a surface shape for forming the water supply passage 79C in the heat transfer plate 73. Yes. As is clear from this figure, the shortest path between the inflow / outflow holes 75 and 77 in the case of extraction and the shortest path between the inflow / outflow holes 78 and 80 in the case of water supply have a convex corrugated plate. A portion 73a is formed. For this reason, as the extraction channel 76C, a lot of extraction gas flows to the side close to the inflow / outflow holes 75, 77 with a small channel resistance, and as the water supply channel 79C, the inflow / outflow holes 78, with a low channel resistance. A lot of water will flow on the side close to 80.

  As a result, on the surface of one heat transfer plate 73 (FIG. 4a), a lot of bleed air flows to the side close to the inflow / outflow holes 75 and 77 to heat this portion, and on the back surface (FIG. 4b) A lot of feed water flows to the side close to the outflow holes 78 and 80 to cool this portion. For this reason, heat exchange from the extracted air on the front surface to the water supply on the back surface is efficiently carried out via one heat transfer plate 73.

  In order to perform this heat exchange efficiently, it is necessary not to let bleed air or water supply pass through the shortest path. For this purpose, a half-surface flow of a gentle corrugated sheet 73a on the flat plate is performed by pressing. Giving way. The overall configuration of the corrugated plate is a gentle mountain shape 73a having a convex central portion. This shape aims at the heat transfer promotion effect by the corrugated plate without giving a large flow loss to the flow. The main design factors such as the pitch and angle with respect to the flow direction are mainly determined by the pressure loss and heat transfer coefficient of the fluid that exchanges heat. Depending on the required performance, the shape and dimensions of the corrugated sheet are appropriately determined. Is adopted.

  FIG. 5 shows a schematic view of a pressure-resistant plate with ribs for support of Example 1, which is a preferred embodiment of the present invention. FIG. 5a is a plan view of a pressure-resistant plate with ribs for support, and FIG. 5b is a cross-sectional view taken along line AA. The pressure plate 74 with the ribs for support is not limited to the interval between the heat transfer plates 73, but is provided in addition to the peripheral plates so that the thin plate is not deformed by the differential pressure of the two fluids sandwiching the heat transfer plate. At least one or more support ribs 74a are installed in a central portion. Also, the direction of the ribs is preferably substantially parallel to the fluid flow direction. In this figure, a plurality of support ribs 74a are provided at the center. As shown in other embodiments, several other embodiments are conceivable.

  FIG. 6 shows a cross-sectional view of the flow path of the heat transfer plate of the first embodiment which is a preferred embodiment of the present invention. In this figure, heat exchange of the feed water heater is taken as an example. The case of the counter flow heat exchange system in which the feed water FB1 flows from the lower left and the extracted steam FA1 flows from the upper left is shown. As is apparent from this cross-sectional view, the corrugated sheet 73a has a gentle sine curve shape and is repeated almost in phase. Therefore, the widths of the flow paths hardly change in the flow direction.

  Therefore, when the water supply and the extracted steam exchange heat, the water supply FB1 only heats up along the flow direction from the inlet and rises in temperature due to sensible heat and rises in temperature. On the other hand, the extraction steam FA1 flows as saturated steam or wet steam, and generates saturated condensed water while exchanging heat. Here, when the steam is condensed to become a saturated liquid, a large volume change occurs, which may cause a hammering phenomenon accompanying a phase change. Thereby, an abrupt impact pressure may be generated.

In order to reduce the load on the corrugated plate due to the sudden impact pressure generated by the volume change of the fluid on the condensing side, the volume of the flow path on the steam side is increased to about twice that on the water supply side, and the condensing hammer Take measures to alleviate the ring phenomenon. Therefore, in the present invention, the ratio of the corrugated plate flow width is set within a range satisfying the following relationship.
[Equation 1]
1 ≦ δ _v / δ _f ≦ 2 (1)
However, [delta] _v is the flow path width of the corrugated sheet passing fluid (bleed) to condense, the [delta] _f shows the channel width of the corrugated sheet to pass fluid (water) is not condensed.

Further, considering the heat exchange phenomena, the overall heat transfer coefficient K is determined from the thermal resistance T _w determined by the heat transfer coefficient and the corrugated thickness t of the respective fluids. Here, in comparison with forced convection heat transfer coefficient h _f of the water supply side, because the condensation heat transfer coefficient h _v of extraction steam side where there is a latent heat transfer by phase change, the performance increases by about one order of magnitude or more. Therefore, it is desirable to design so as to ensure the minimum value of the heat transfer coefficient h _f on the water supply side. In this case, in order to reduce the thermal resistance due to the corrugated sheet thickness t, it is necessary to make the sheet thickness within a range of about 1 mm to 2 mm even if it is thick.

  On the other hand, the two fluids to be heat-exchanged each have a pressure condition to be supplied, and a plate thickness t that can withstand the differential pressure ΔP is required. Here, if the pressure-resistant plate 74 with ribs for support shown in FIGS. 3 and 5 is not provided, the deformation of the flat plate due to this large pressure difference becomes severe. In contrast, in the present invention, as shown in the figure, the flat plate of the heat transfer plate can be divided finely and deformation due to the differential pressure received by the flat plate can be suppressed, so that the plate thickness t of the heat transfer plate can be kept thin. it can.

For example, the pressure condition of the extracted steam is in a range from 1.3 MPa to a maximum of 2.4 MPa. On the other hand, the pressure of the water supply is in a wide range from 0.5 MPa to 7 MPa. Therefore, in each feed water heater, in order to appropriately determine the design specifications of the heat transfer plate with respect to the differential pressure (0.1 to 1.5 MPa) of various fluids, the differential pressure ΔP between the two fluids to be heat exchanged and the heat As a relationship of the corrugated sheet thickness t sandwiching the two fluids to be exchanged, it is necessary to satisfy the following range so that the overall heat transfer coefficient is 1 kW / m ² K or more.
[Equation 2]
1 × 10 ³ ≦ ΔP / t ≦ 1 × 10 ⁴ MPa / m (2)
The inventors examined the heat exchange characteristics of the first high-pressure feed water heater 16A, which is a shell-plate feed water heater used in this example. The result of this examination will be described below with reference to FIGS. In this study, the heat exchange characteristics of an indirect feed water heater using conventional heat transfer tubes were also examined.

  FIG. 7a shows heat exchange using a conventional shell and tube feed water heater for the first high-pressure feed water heater 16A, and FIG. 7b shows heat exchange using a shell and plate feed water heater. The horizontal axis of FIG. 7a has shown the position X1 in the flow direction of the feed water of the 1st high pressure feed water heater 16A. Specifically, the position X1 is a position from the inlet end of the heat transfer tube of the shell-and-tube type feed water heater. The horizontal axis of FIG. 7b has shown the position X2 in the flow direction of water supply. The vertical axis in FIGS. 7a and 7b represents temperature.

  When the first high-pressure feed water heater 16A is a shell and tube feed water heater (FIG. 7a), both the terminal temperature difference TD and the drain cooler temperature difference DC representing the temperature difference between the two fluids to be heat-exchanged are large values. On the other hand, in the shell / plate type feed water heater, both the terminal temperature difference TD and the drain cooler temperature difference DC are small. This is influenced by the size of the element that becomes a thermal resistance to transfer heat when the two fluids exchange heat.

When the first high-pressure feed water heater 16A is a shell and tube feed water heater, the heat resistance network (see FIG. 7a) has three types of heat resistance (1 / h _s , t / λ, 1 / h _t ), the thermal resistance network (see FIG. 7 b) consisting of a shell and plate feedwater heater is also divided into three types of thermal resistance (1 / h _s , t / λ, 1 / h _p ). However, turbulence promoting effect caused by flowing wave plates, if the shell plate-type water heater, comprising heat transfer coefficient h _s and h _p are both large. Therefore, since the heat transfer rate, that is, the heat transmission rate in the first high-pressure feed water heater 16A is larger than that of the conventional shell-and-tube feed water heater, the terminal temperature difference TD and the drain cooler temperature in the first high-pressure feed water heater 16A. The difference DC is both reduced.

  FIG. 8 shows the relationship between the heat exchange performance and the space volume of the shell / plate type feed water heater. The horizontal axis of FIG. 8 shows the volume V of the feed water heater, and the vertical axis shows the ratio of the exchange heat quantity Q to the pressure loss ΔP.

  According to this analysis result, the volume V of the feed water heater in the case of the shell-and-tube type feed water heater of FIG. 7a is 1.0, and the ratio of the exchange heat quantity Q to the pressure loss ΔP is 1.0. In the case of the present invention, the space volume can be reduced to about 1/5. In addition, since a large heat transfer acceleration effect can be expected by using the gentle shape of the corrugated plate, the pressure loss is the same as the current level, and the heat exchange performance is about 1.2 times or more. There is also an advantage that the space for disassembly and inspection can be greatly reduced.

  On the other hand, as a reference, a plate-fin type that can reduce the space volume to about 1/8 and can secure the same heat exchange performance as the present invention is also shown. In this result, the plate-fin type is advantageous in terms of performance, but this method is limited to use at low temperatures and low pressures of 100 ° C or less and 0.2MPa or less. Does not match. Therefore, a feature of the present invention is that a compact and high-performance heat exchange performance can be ensured even when used under high temperature and high pressure conditions.

  The reduction of the volume of the first high-pressure feed water heater 16A described above to about 1/5 and the improvement of the heat exchange performance by about 1.2 times can be achieved by heating the remaining five feed water heaters in the boiling water nuclear power plant 1. This can also be achieved with the instruments 16B, 17A-17D.

  In existing boiling water nuclear power plants, it is only necessary to add one compact and high performance shell / plate type water heater without changing any of the multiple shell / tube type water heaters installed. The temperature of the feed water supplied to the nuclear reactor 2 can be increased by about 20 ° C.

  When all of the six feed water heaters provided in the feed water pipe 15 are shell plate type feed water heaters, the temperature of the feed water supplied to the reactor 2 from the first high-pressure feed water heater 16A in the final stage is Compared with the case where all of the six water heaters are shell / tube type water heaters, the heat exchange performance of the former is about 1.2 times that of the latter. In the present embodiment, since six shell plate type water heaters are provided in the water supply pipe 15, the turbine building in which the water supply pipe 15 is installed can be made compact.

  Further, in this embodiment, since the water supply and the steam stably exchange heat through the corrugated plate in the container 50, the flow of the water supply generated when the above-described steam injector is used becomes unstable. Can be prevented.

  In this embodiment, the extracted steam extracted from the high-pressure turbine 3 and the low-pressure turbines 5A, 5B, 5C, etc. is supplied to the high-pressure feed water heaters 16A and 16B and the low-pressure feed water heaters 17A to 17D, which are shell-plate type feed water heaters. Then, since the water supply is heated by exchanging heat with the water supply in each container 50, the heat of the steam generated in the nuclear reactor 2 is recovered and the temperature of the water supply supplied to the nuclear reactor 2 can be raised. it can. For this reason, the thermal efficiency of the boiling water nuclear power plant 1 is improved. In particular, the heat exchange between the feed water and steam is performed by a compact heat transfer plate element in which the heat transfer area per volume in the container 50 is large, so even if the temperature difference between both fluids performing heat exchange is small, a large amount of exchange heat can be obtained. Can be secured. For example, by changing all of the current shell / tube type feed water heaters to the shell / plate type feed water heaters of the present invention, the feed water temperature supplied to the reactor can be raised to at least 235 ° C. or more and up to 250 ° C. or more. Therefore, the thermal efficiency can be improved by about 0.3%.

  As described above, in this embodiment, since heat exchange is performed between the feed water and the extracted steam fluid in all the feed water heaters, the heat exchange performance in all the feed water heaters becomes high performance. For this reason, in this embodiment, it is necessary to increase the flow rate of the extraction steam supplied to the feed water heater as in the conventional boiling water nuclear power plant in which all the feed water heaters are shell tube type feed water heaters. The feed water temperature can be sufficiently increased even with a small amount of extracted steam.

  As a result, in the boiling water nuclear power plant 1, in the rated power operation of the reactor, the main steam flow rate is increased by the amount that the enthalpy difference between the reactor water and the main steam is reduced. Compared with the conventional boiling water nuclear power plant in which all feed water heaters are shell and tube type feed water heaters, the boiling water nuclear power plant 1 is supplied to the high pressure turbine 3 and the low pressure turbines 5A, 5B, 5C. Increased steam volume. Therefore, in this embodiment, the work amount due to steam in the high-pressure turbine 3 and each low-pressure turbine increases, and the electrical output can be improved. This means that in the boiling water nuclear power plant 1, the power improvement operation for further increasing the rated reactor power is substantially performed.

  In this embodiment, high-pressure feed water heaters 16A and 16B and low-pressure feed water heaters 17A to 17D, which are shell and plate type feed water heaters, are installed in the feed water pipe 15 to supply the extracted steam from the high-pressure turbine 3 or the low-pressure turbine. The heat exchange between the extracted steam and the feed water allows efficient heat exchange between the extracted steam and the feed water. For this reason, the temperature of feed water can be raised with little energy. Since the temperature of the steam supplied to each low-pressure turbine rises and the amount of expansion of the steam in the low-pressure turbine increases, the work by the steam in the low-pressure turbine increases. This also further improves the electrical output of the boiling water nuclear power plant 1.

  In this embodiment, since the flow rate of the extraction steam extracted from the high-pressure turbine and the low-pressure turbine and supplied to the corresponding shell plate type feed water heater is small, the main steam flow rate working in the high-pressure turbine and the low-pressure turbine is low. Increases the electrical output. Furthermore, the heat generated in the nuclear reactor 2 which is a steam generator can be used effectively in the boiling water nuclear power plant 1, and the hot wastewater discharged from the condenser 11 to the sea through the seawater discharge pipe 13B. The amount of heat can be reduced. Therefore, the thermal efficiency in the boiling water nuclear power plant 1 of the regeneration cycle can be further improved.

  Next, an example of the system configuration when the shell-plate type feed water heater of the present invention is applied to the moisture separator superheater will be specifically described with reference to FIG. As shown in FIG. 9, the moisture separation superheater 33 is provided with a moisture separator 43, a first stage superheater 34A, and a second stage superheater 34B as main devices in a horizontally placed container 41. . The moisture separator 43 is arranged in a Y shape at the bottom in the container.

  Here, the moisture separator 43 has a mechanism for removing the wet droplets in the wet steam 40a flowing in from the lower part of the container 41. The steam uniform inflow mechanism 42 is installed upstream thereof, so that the steam 40a flowing in from below is rectified so as to uniformly flow into the moisture separator 43 arranged in a Y shape.

  Moisture is removed by the moisture separator 43, and the main steam flow 40 discharged from the moisture separator 43 is then sent to the first stage superheater 34 </ b> A disposed on the upstream side of the central portion in the container 41. It is guided and superheated using steam extracted from the high pressure turbine. Further, the second stage superheater 34B arranged on the downstream side of the upper part in the container 41 uses the steam 49a extracted from the main steam pipe upstream from the high-pressure turbine from the steam superheated by the first stage superheater 34A. Use to overheat. Then, the steam 40b superheated by the second stage superheater 34B is supplied to the low pressure turbine.

  On the other hand, the extraction steam flow 49a for superheating the main steam flow 40 is guided to the inlet side steam chamber 47, and after the heat exchange in the first stage superheater 34A and the second stage superheater 34B, the outlet side steam The saturated condensed drain water 49b is discharged from the chamber 48.

  In the case of the moisture separation superheater shown in FIG. 9, the feed water heater shown in FIG. 1 is different in the introduction and discharge positions of the heated fluid and the heated fluid. The two-stage superheater 34 </ b> B is also a shell plate type heat exchanger, and includes a heat transfer plate layer 54. A guide mechanism 46 is provided outside the heat transfer plate layer 54 in order to isolate the heat transfer plate layer 54 from the container 41. An intermediate medium may be enclosed between them.

  As described above, in order to improve the thermal efficiency of the boiling water nuclear power plant of BWR or ABWR, the moisture separation efficiency of the moisture separator can be improved, and the moisture separation superheater can be made compact and high performance. The plant efficiency is improved by improving the reheat cycle. Moreover, since the container of the conventional moisture separation superheater is reduced in size, it can contribute also to the compactness to the whole building at the time of installing a moisture separation superheater.

  In this embodiment, since the heat transfer plate, which is a shell plate type heat exchanger, is installed in the first stage superheater and the second stage superheater without installing the conventional heat transfer tube, heat exchange for superheat is performed. The element does not grow. Therefore, the heat exchange performance of the moisture separation superheater is improved as in the above-described feed water heater. For this reason, the thermal efficiency of a boiling water nuclear power plant can be improved.

  As a result, soundness due to erosion of the blades of the low-pressure turbine can be ensured, and at the same time, the thermal efficiency of the BWR plant can be improved.

  The present embodiment can also be applied to an improved boiling water nuclear power plant (ABWR power plant) using an internal pump as a pump for supplying cooling water to the core. Examples 2 to 4 described later can also be applied to the ABWR power plant.

  In the boiling water nuclear power plant 1 of the present embodiment, a shell and plate heat exchanger without a heat transfer tube, that is, a container, is not a feed water heater using a shell and tube heat exchanger having a heat transfer tube. 50, a feed water heater (for example, the first high-pressure feed water heater 16A) that condenses the feed water (subcool water) supplied by the feed water pump via the corrugated plate plate and the steam extracted from the high-pressure turbine 3 for heat exchange. Can be used.

  In FIG. 10, the schematic of the heat-transfer plate of Example 2 which is another Example of this invention is shown. It is the figure which looked at one heat-transfer plate 73 from the front. Inflow / outflow holes (75, 77, 78, 80) for the heating fluid FA and the heated fluid FB are opened at the four corners of the top, bottom, left, and right. The other surface is provided with a gentle corrugated flow path 73b on the flat plate by pressing. The overall structure of the corrugated plate is a gentle mountain shape with a concave central part. This is the opposite shape to FIG. This shape is also one aiming at the heat transfer enhancement effect by the corrugated plate without giving a large loss to the flow. The main design factors such as the pitch and angle with respect to the flow direction are mainly determined by the pressure loss and heat transfer coefficient of the fluid that exchanges heat. Depending on the required performance, the shape and dimensions of the corrugated sheet are appropriately determined. Is adopted.

  FIG. 11 shows a schematic view of a pressure-resistant plate 74 with ribs for support according to embodiment 3, which is another embodiment of the present invention. Compared to the support ribs 74a that are installed in the simplest center as shown in FIG. 5, a tie-type support rib 74b is installed in FIG. Thereby, the pressure resistance strength of the heat transfer plate 73 is improved, and at the same time, the flow of the fluid to be exchanged with heat is not significantly changed, so that the pressure loss and the heat transfer coefficient are not greatly affected. is there.

  In addition to the other embodiments shown in FIG. 5, there are many examples of support ribs that are divided into minute cells so as to prevent deformation of the heat transfer plate.

  The heat exchange element of the shell-plate heat exchanger according to the present invention involves condensation of low-temperature seawater and low-pressure main steam from the low-pressure turbine in addition to the moisture separation superheater MSH and feed water heater in the power plant. You may use also for heat exchangers, such as a condenser which performs heat exchange.

  In this case, the condenser, which is a heat exchanger, is configured to perform heat exchange using steam discharged from the steam turbine as a heating fluid and seawater, which is cooling water, as a heated fluid. Also in this case, the apparatus configuration of the heat exchanger can be realized using the concept of heat exchange in FIG. 1 or FIG.

  The heat exchange element of the shell-plate heat exchanger of the present invention includes a dynamic low-pressure water injection heat removal operation as a heat removal means in addition to the moisture separation superheater MSH and the feed water heater in the nuclear power plant. Residual heat removal system (RHR) that is a mode, or an emergency condenser (IC) and static containment vessel cooling system (PCCS) that is a system that condenses steam by a natural force without a driving source such as a pump, or an auxiliary machine You may use also for heat exchangers, such as a cooler.

  In addition, although the present Example took the boiling water light water reactor plant as an example, this invention is applicable also to the secondary system of a pressurized water light water reactor, and other types of nuclear power generation systems. Moreover, it is possible to apply to various heat exchangers of power plants using fossil fuels other than nuclear power generation.

  The present invention can be applied to nuclear power plants such as boiling water nuclear power plants and pressurized water nuclear power plants, and power plants such as thermal power plants.

DESCRIPTION OF SYMBOLS 1 ... Boiling water type nuclear power plant 2 ... Reactor 3 ... High pressure turbine 4 ... Moisture separator 5 ... Low pressure turbine 6 ... Main steam piping 8 ... Main steam control valve 9 ... Generator 10 ... Main shaft 11 ... Condenser 12 ... heat transfer pipe 13B ... seawater discharge pipe 14 ... seawater circulation pump 15 ... feed water pipe 16 ... high pressure feed water heater 17 ... low pressure feed water heater 18 ... condensate pump 19 ... feed water pumps 20 to 25 ... bleed pipes 26, 35, 39 ... Drain pipe 33 ... moisture separator superheater 34A ... first stage superheater 34B ... second stage superheater 40 ... main steam flow 41 ... barrel 42 ... steam uniform inflow mechanism 46 ... heat transfer plate layer guide 47 ... inlet side steam chamber 48 ... Outlet side steam chamber 49 ... Extraction steam flow 49a ... Extraction steam inflow 49b ... Extraction steam outflow 50 ... Body 51 ... Tube plate 52 ... Water chamber 53 ... Partition plate 54 ... Heat transfer plate layer 54a ... Heat transfer plate 1 unit 54b ... Heat transfer plate Guide 55 ... Intermediate medium 56 ... Condensed water pot 71 ... S plate 72 ... E plate 73 ... Heat transfer plate 73a ... Corrugated shape 74 ... Pressure-resistant plate 75 with ribs for support ... Extraction steam inflow hole 77 ... Extraction steam outflow hole 78 ... Water supply inflow hole 80 ... Water supply outflow hole

Claims (17)

A steam generator that introduces feed water and generates steam; a steam turbine that introduces steam from the steam generator to drive a generator; and a condenser that condenses the steam discharged from the steam turbine; And a heat exchanger that sends the condensate of the condenser as the feed water to the steam generator, and uses the feed water or the steam as a heated fluid, and performs heat exchange using the extracted air from the steam turbine as a heating fluid. In a power plant,
The heat exchanger is configured by alternately stacking heat transfer plates and pressure plates in a pressure-resistant shell through a space in a non-contact manner, and the first and second pressure resistances on both sides of the heat transfer plate. About the plate, the heating fluid is introduced into the first flow path formed by the space between the first pressure plate and the heat transfer plate, and the space between the second pressure plate and the heat transfer plate By introducing the heated fluid into the second flow path formed by the above, the heated fluid flow path and the heated fluid flow path are formed on each surface of the heat transfer plate sandwiched between the pressure-resistant plates. A power plant equipped with a shell-and-plate heat exchanger characterized by heat exchange. In the power plant provided with the shell plate type heat exchanger according to claim 1,
A power plant equipped with a shell-plate type heat exchanger, wherein corrugated corrugated plates are formed in the flow path on each surface of the heat transfer plate. In the power plant provided with the shell plate type heat exchanger according to claim 2,
When a condensation phenomenon occurs due to heat exchange in the heat exchanger, the flow path width of the corrugated plate of the heat transfer plate through which the fluid to be condensed passes is δ _v , and the corrugated plate of the heat transfer plate through which the fluid that does not condense passes when the channel width [delta] _f, power plants the ratio of channel width of the wave plate having a shell plate heat exchanger, characterized in that the range satisfying the following relation.
1 ≦ δ _v / δ _f ≦ 2 In the electric power plant provided with the shell plate type heat exchanger according to claim 2 or claim 3,
A shell / plate type heat exchanger characterized in that a differential pressure ΔP of two fluids exchanging heat in the heat transfer plate and a thickness t of a corrugated plate of the heat transfer plate satisfy the following relationship: Power plant equipped.
1 × 10 ³ ≦ ΔP / t ≦ 1 × 10 ⁴ MPa / m In the power plant provided with the shell plate type heat exchanger according to any one of claims 1 to 4,
The shell, characterized in that the pressure plate sandwiching the heat transfer plate has at least a quadrangular four-sided frame as a rib, and at least one intermediate support rib is installed substantially in parallel with the fluid flow inside. A power plant equipped with a plate heat exchanger. A steam generator that introduces feed water and generates steam; a steam turbine that introduces steam from the steam generator to drive a generator; and a condenser that condenses the steam discharged from the steam turbine; A feed water heater that heats the condensate of the condenser, and a power plant that is configured to send feed water heated in the feed water heater to the steam generator,
The feed water heater is a heat exchanger that performs heat exchange using the condensate from the condenser as a heated fluid and the extraction air from the steam turbine as a heating fluid, and the heat exchanger has a pressure resistance A unit in which a heat transfer plate and a pressure plate are alternately stacked in a non-contact manner through a space is fixed in a shell, and the first and second pressure plates on both sides sandwiching the heat transfer plate in the unit are The heating fluid is introduced into a first flow path formed by a space between the pressure plate and the heat transfer plate, and a second formed by the space between the second pressure plate and the heat transfer plate. By introducing the heated fluid into the flow path of
A shell / plate type heat exchanger is provided in which heat exchange is performed by forming a flow path of the heated fluid and a flow path of the heated fluid on each surface of a heat transfer plate sandwiched between pressure-resistant plates. Power plant. In the power plant provided with the shell plate type heat exchanger according to claim 6,
A plurality of the feed water heaters are installed between the steam generator and the condenser, and at least one of the feed water heaters is the shell plate type heat exchanger.・ Power plant with plate heat exchanger. In the power plant provided with the shell plate type heat exchanger according to claim 6 or 7,
The feed water heater composed of the shell-plate heat exchanger has a guide mechanism for fixing the unit installed therein, and an intermediate medium is enclosed between the shell and the guide mechanism. A power plant with a shell-and-plate heat exchanger. In the power plant provided with the shell plate type heat exchanger according to any one of claims 6 to 8,
Install high-pressure and low-pressure feed water heaters composed of the shell-and-plate heat exchanger, raise the feed water temperature supplied to the reactor to at least 235 ° C, and improve thermal efficiency by about 0.1% or more A power plant equipped with a shell-and-plate heat exchanger. A steam generator that introduces feed water and generates steam; a steam turbine that introduces steam from the steam generator to drive a generator; and a condenser that condenses the steam discharged from the steam turbine; The condensate of the condenser is sent to the steam generator as the feed water, and the steam turbine is composed of a high-pressure turbine and a low-pressure turbine, and the steam discharged from the high-pressure turbine is converted into a moisture separator and a superheater. In a power plant adapted to be introduced into the low-pressure turbine via a moisture separator superheater comprising:
The superheater of the moisture separation superheater is a heat exchanger that performs heat exchange using steam discharged from the high-pressure turbine as a heated fluid, and extracting air from the steam turbine as a heating fluid, the heat exchanger Fixes a unit in which heat transfer plates and pressure plate are alternately stacked in a non-contact manner in a pressure-resistant shell, and the first and second pressure plates on both sides sandwiching the heat transfer plate in the unit The heating fluid is introduced into the first flow path formed by the space between the first pressure plate and the heat transfer plate, and the space between the second pressure plate and the heat transfer plate is used. By introducing the heated fluid into the formed second flow path,
A shell / plate type heat exchanger is provided in which heat exchange is performed by forming a flow path of the heated fluid and a flow path of the heated fluid on each surface of a heat transfer plate sandwiched between pressure-resistant plates. Power plant. In the power plant provided with the shell plate type heat exchanger according to claim 10,
The superheater of the moisture separation superheater is composed of a first-stage superheater and a second-stage superheater on the downstream side, and the first-stage superheater is supplied with extraction air from the high-pressure steam turbine as a heating fluid. The second stage superheater is provided with a shell-plate heat exchanger, wherein steam before flowing into the high-pressure steam turbine is supplied as a heating fluid. In the power plant provided with the shell plate type heat exchanger according to claim 10 or 11,
A shell / plate type heat, wherein a guide mechanism for fixing the unit is installed in a superheater installed in the moisture separation superheater, and an intermediate medium is sealed between the shell and the guide mechanism. A power plant with an exchanger. A steam generator that introduces feed water to generate steam, a steam turbine that introduces steam from the steam generator to drive a generator, and condensates by cooling the steam discharged from the steam turbine with seawater And a power plant adapted to send the condensate of the condenser as feed water to the steam generator,
The condenser is a heat exchanger that performs heat exchange using steam discharged from the steam turbine as a heating fluid and seawater as a fluid to be heated, and the heat exchanger is transferred into a pressure-resistant shell. A unit in which heat plates and pressure plates are alternately stacked in a non-contact manner through a space is fixed, and the first and second pressure plates on both sides sandwiching the heat transfer plate in the unit are The heating fluid is introduced into a first flow path formed by a space between the heat transfer plates, and a second flow path formed by a space between the second pressure-resistant plate and the heat transfer plate. By introducing the heated fluid,
A shell / plate type heat exchanger is provided in which heat exchange is performed by forming a flow path of the heated fluid and a flow path of the heated fluid on each surface of a heat transfer plate sandwiched between pressure-resistant plates. Power plant. A heat exchanger for exchanging heat between a heated fluid and a heated fluid, wherein the heat exchanger is formed by alternately stacking heat transfer plates and pressure plates in a non-contact manner through a space in a pressure resistant shell. The first flow path formed by the space between the first pressure-resistant plate and the heat-transfer plate with respect to the first and second pressure-resistant plates on both sides sandwiching the heat-transfer plate in the unit The heated fluid is introduced into the second flow path, and the heated fluid is introduced into a second flow path formed by a space between the second pressure-resistant plate and the heat-transfer plate. A shell / plate type heat exchanger characterized in that heat exchange is performed by forming a flow path of the heated fluid and a flow path of the heated fluid on each surface of the heat plate.   The shell-and-plate type heat exchange according to claim 14, wherein the shell-and-plate type heat exchange is used as a heat exchanger of a residual heat removal system which is a heat removal operation mode of a dynamic low-pressure water injection system as a heat removal means of a nuclear power plant vessel.   The shell-and-plate type heat exchange according to claim 14, which is used as an emergency condenser which is a system for condensing steam by natural force without a driving source such as a pump as heat removal means of a nuclear power plant. vessel.   The shell according to claim 14, wherein the shell is used as a heat exchanger of a static containment vessel cooling system, which is a system for condensing steam by natural force without a driving source such as a pump, as heat removal means of a nuclear power plant.・ Plate heat exchanger.

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