JP2010121911A - Moisture separation heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve plant efficiency by reducing a flow rate of cycle steam flowing through a body interior and reducing its pressure loss or the like. <P>SOLUTION: The moisture separation heater 12 of a one-stage reheat type includes the body 17, a cycle steam inlet 18 provided in a bottom of the body and introducing the cycle steam into the body, an MS element 21 obliquely disposed in a lower region of a body interior and separating moisture in the cycle steam, and a heater 22 disposed in a substantially center region of the body interior and equipped with a plurality of heat transfer tubes 31 carrying heating steam and a single heating steam head 32 communicated with the heat transfer tubes. A tube bundle size W/H is set so that the expression, 1.6<W/H<1.9, is satisfied when a lateral width of a tube bundle in the plurality of heat transfer tubes 31 is W and a height is H, and the heating steam header is made into a transverse installation cylindrical type. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a moisture separation heater, and more particularly to a one-stage reheat type moisture separation heater in which the heater has a single heating steam header.

  As shown in Patent Document 1 and FIGS. 14 and 15, a conventional one-stage reheat type moisture separation heater 100 includes a body 101 made of a horizontal cylindrical container, and receives wet cycle steam from a high-pressure steam turbine. It is introduced from a cycle steam inlet 102 provided on one end plate, and is provided by an MS element 103 (the MS element is a moisture separation element, and “MS” is an abbreviation of moisture separator) in the lower part of the body 101. After the moisture is separated and removed, it is heated by the heater 104 in the upper part of the fuselage 101, and superheated steam is supplied from the cycle steam outlet 105 at the top of the fuselage 101 to the low-pressure steam turbine. The heating steam header 106 of the heater 104 is installed so as to protrude to the outside of the end plate opposite to the end plate into which the cycle steam flows.

  In order to make the heated steam header 106 compact, the horizontal width W and height H of the tube bundle in the plurality of heat transfer tubes 107 of the heater 104 are made equal (for example, about W / H <1.3), and the circular tube plate 108. It is common to reduce the diameter.

  The above-described one-stage reheat type moisture separator / heater 100 is a device in the early stage of a nuclear power plant, and many of them use a copper alloy for the heat transfer tube 107, and recently, a heat transfer tube 107 made of stainless steel is used. More and more plants are being renewed. The present invention is intended to update such a one-stage reheating type moisture separation heater 100.

  Also, a two-stage reheating type moisture separation heater in which two heating steam headers are arranged inside the fuselage is disclosed as a moisture separation heater for flowing cycle steam from the lower part of the fuselage (see Patent Document 2). ).

Further, Patent Document 3 discloses a moisture separation heater in which an orifice plate is provided on a tube plate in the vicinity of a heating steam header in order to prevent overcooling of the condensed drain generated in the heat transfer tube of the heater.
Japanese Utility Model Publication 2-7411 Japanese Utility Model Publication 2-7410 JP-A-49-72503

  By the way, in the one-stage reheating type moisture separation heater 100 shown in Patent Document 1 and FIG. 14 and the like, since the cycle steam is introduced from the cycle steam inlet 102 installed in the end plate, the MS element 103 is reached. The flow path is narrow, the flow velocity of the cycle steam flowing through this flow path is increased, and the pressure loss of the steam is increased. When the height h of the MS element 103 is low, the quantity of the MS element 103 can be reduced, but the flow rate of the cycle steam passing through the MS element 103 becomes high, and the pressure loss of the cycle steam becomes large.

  Further, in the moisture separation heater 100 of the type in which the heating steam header 106 is installed so as to protrude outside the end plate, the horizontal width W of the tube bundle of the heat transfer tubes 107 becomes narrow, and the flow of cycle steam passing outside the tube bundle is reduced. Although it becomes faster, the heat transfer area becomes smaller, but the pressure loss of the cycle steam passing between the bundles of the heat transfer tubes 107 becomes larger, which causes the plant efficiency to deteriorate.

  If the width W of the bundle of heat transfer tubes 107 is increased, the inner diameter of the heating steam header 106 is increased, and the heating steam header 106 has a high internal pressure, so that the wall thickness is increased. As a result, the moisture separation heater 100 The weight will increase.

  Further, in the moisture separator / heater 100 in which the cycle steam is introduced from the cycle steam inlet 102 installed in the end plate, an internal structural material (for example, a steam rectifying plate (not shown) near the cycle steam inlet 102 is caused by the influence of the steam flow. The attachment member or the like may be damaged.

  The object of the present invention has been made in consideration of the above-mentioned circumstances, and is a moisture separation heating that can improve the plant efficiency by reducing the flow rate of cycle steam flowing through the fuselage and reducing its pressure loss. Is to provide a vessel.

  Another object of the present invention is to provide a moisture separation heater that can simplify the system configuration.

  The present invention provides a fuselage, a cycle steam inlet that is provided at the bottom of the fuselage and introduces cycle steam into the fuselage, and is disposed at an inclination in a lower region of the fuselage and separates moisture in the cycle steam. A separation element; and a heater having a plurality of heat transfer pipes arranged in a substantially central region in the fuselage for flowing the heating steam, and a single heating steam header communicating with the heat transfer pipes. This is a one-stage reheat type moisture separation heater, where the tube bundle size W / H is 1.6 <W / H, where W is the width of the tube bundle and H is the height of the plurality of heat transfer tubes. <1.9, and the heating steam header is configured in a horizontal cylinder shape.

  According to the present invention, the cycle steam flows from the cycle steam inlet provided at the bottom of the fuselage and is guided to the MS element disposed in the lower region of the fuselage, so that the cycle steam flows through a narrow region of the fuselage. In other words, the flow rate of the cycle steam from the cycle steam inlet to the MS element can be reduced. Further, the heater is arranged in a substantially central region in the fuselage, the horizontal width W of the tube bundle of the heat transfer tubes in the heater is increased with respect to the height H, and the tube bundle size W / H is 1.6 <W / H. Since it was set to <1.9, the flow velocity of the cycle steam that passes outside the plurality of heat transfer tubes can be reduced. As a result, the pressure loss of the cycle steam that flows from the cycle steam inlet into the fuselage and sequentially flows through the MS element and the heater can be reduced, and the plant efficiency can be improved.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, the present invention is not limited to these embodiments.

[A] First embodiment (FIGS. 1 to 10)
FIG. 1 is a system diagram showing a first embodiment of a moisture separation heater according to the present invention together with a piping system. FIG. 2 is a longitudinal sectional view showing the moisture separation heater of FIG.

  As shown in FIG. 1, most of the steam generated in a steam generator 10 such as a boiler or a nuclear reactor is led as cycle steam to a high-pressure steam turbine 11 to perform work. The moisture is removed and heated and guided to the low-pressure steam turbine 13, and after working in the low-pressure steam turbine 13, the water reaches the condenser 14 and is condensed into water, which is not shown by a condensate pump and a feed water pump (not shown). The pressure is increased in sequence and returns to the steam generator 10. A part of the steam from the steam generator 10 is guided to a heating steam header 32 (described later) of the moisture separation heater 12.

  As shown in FIG. 2, the moisture separator / heater 12 includes a body 17, a cycle steam inlet 18 provided at the bottom of the body 17, a first MS drain port 19, a second MS drain port 20, and a body 17. The MS element 21 and the heater 22 arranged inside, and a cycle steam outlet 23 provided at the top of the body 17 are configured.

  The body 17 has a cylindrical shape, and is configured in a horizontal type with a flange-shaped end plate 24 fixed to both ends. A plurality of, for example, two cycle steam inlets 18 are installed at the bottom of the body 17 to introduce the cycle steam from the high-pressure steam turbine 11 into the body 17. A steam distribution plate 25 is provided immediately above the cycle steam inlet 18 as shown in FIG. The cycle steam introduced from the cycle steam inlet 18 is guided by the steam distribution plate 25 so as to spread over the entire lower region in the body 17.

  As shown in FIGS. 2 and 3, a pair of MS elements 21 are disposed in the body 17 so as to extend along the axial direction of the body 17 in the lower region of the cross section of the body 17. Each MS element 21 is inclined to ensure a large area for the cycle steam to pass through. The cycle steam flowing from the cycle steam inlet 18 and guided by the steam distribution plate 25 is separated from moisture before passing through the MS element 21 and while passing through the MS element 21.

  Moisture (water) separated while passing through the MS element 21 flows down to the first MS drain port 19, is discharged as a drain to the MS drain tank 28 through the first MS drain pipe 26, and is further supplied to the feed water heater 29 (FIG. Discharged to 1). Further, moisture (water) separated before passing through the MS element 21 flows down to the second MS drain port 20, passes through the second MS drain pipe 27, and the pressure adjustment disposed in the second MS drain pipe 27. It reaches the first MS drain pipe 26 via the mechanism 30 and is sequentially discharged as drain to the MS drain tank 28 and the feed water heater 29.

  Since the pressure in the second MS drain port 20 and the second MS drain pipe 27 is slightly higher than the pressure in the first MS drain port 19 and the first MS drain pipe 26, the pressure adjustment mechanism 30 The drain in the 2MS drain pipe 27 is surely discharged to the MS drain tank 28 through the first MS drain pipe 26 by gravity. For example, a U seal (which will be described in detail in a second embodiment described later) is used as the pressure adjusting mechanism 30.

  The heater 22 is a one-stage reheat type, and as shown in FIGS. 2 and 3, a plurality of U-shaped heat transfer tubes 31 and a single heating in which both ends of these heat transfer tubes 31 are communicated with each other. And a steam header 32. The heat transfer tube 31 and the heating steam header 32 are arranged in a substantially central region of the cross section of the body 17 in the body 17. Among these, the heat transfer tube 31 extends in the axial direction of the body 17, and a part of the steam from the steam generator 10 shown in FIG. 1 flows and flows through the heating steam header 32 as heating steam. As shown in FIG. 2 and FIG. 3, the cycle steam from which moisture has been removed by the MS element 21 in the body 17 is heated steam that flows inside the heat transfer tubes 31 while flowing outside the plurality of heat transfer tubes 31. Exchanges heat with steam to form superheated steam. The cycle steam that has become the superheated steam flows out of the cycle steam outlet 23 and is led to the low-pressure steam turbine 13 through the crossover pipe 33 shown in FIG.

  By the way, as shown in FIG.4 and FIG.7, the heating steam header 32 of the heater 22 is cylindrical shape, and is comprised by the horizontal installation cylindrical shape which has arrange | positioned the long axis sideways. Also, as shown in FIG. 3, when the horizontal width of the tube bundle of the plurality of heat transfer tubes 31 is W and the height is H, the tube bundle size W / H is set to 1.6 <W / H <1.9. Is done.

  As shown in FIG. 7, when the body diameter of the body 17 is D, the heating steam header diameter of the heating steam header 32 is d, and the heating steam header length is l, the heating steam header diameter ratio d / D and the tube bundle size W FIG. 9 shows the relationship between / H and FIG. 10 shows the relationship between the heated steam header length ratio 1 / D and the tube bundle size W / H. In order to reduce the steam pressure loss due to the MS element 21, the MS element 21 in FIG. 3 must be taken longer in the height direction, and d must be reduced. It was found that the steam pressure loss can be reduced when the heated steam header diameter ratio d / D is smaller than about 0.4. At this time, W / H> 1.6. On the other hand, for l, it is better that the width is large, but the design structure cannot be established unless l / D is smaller than about 0.85. At this time, W / H <1.9. Therefore, assuming that the body diameter D is constant, the heating steam header diameter ratio d / D becomes smaller at W / H> 1.6, and the heating steam header length ratio 1 / D becomes W / H <1.9. Becomes smaller. As shown in FIG. 8, the pressure loss ΔP of the cycle steam that flows outside the plurality of heat transfer tubes 31 decreases as the tube bundle size W / H decreases. Therefore, the tube bundle size W / H is set to 1.6 <W / H. By setting <1.9, the pressure loss of the cycle steam which passes the heater 22 is low, and the heating steam header 32 becomes the compact moisture separation heater 12.

  Further, as shown in FIG. 1, the high-pressure steam turbine 11 and the plurality of (for example, two) cycle steam inlets 18 of the moisture separation heater 12 are connected by a cross-under pipe 34. The cross-under pipe 34 is a branch pipe that is branched into a plurality of (for example, two) pipes on the way and includes a branch section 34 </ b> A. Each end of the branch section 34 is attached to the cycle steam inlet 18. Accordingly, the cycle steam discharged from the high-pressure steam turbine 11 is guided to the cycle steam inlet 18 of the moisture separator / heater 12 through the cross under pipe 34, but the flow path cross-sectional area at the branch portion 34 </ b> A of the cross under pipe 34. Therefore, the flow rate of the cycle steam is reduced in the branch part 34A, and the cycle steam inlet 18 is reached with the pressure loss reduced.

  As shown in FIGS. 4, 5, and 6, the inside of the heating steam header 32 of the heater 22 is divided into an inlet chamber 37, an intermediate chamber 38, and an outlet chamber 39 by partition members 35 and 36. A heating steam inlet pipe 40 that introduces steam from the steam generator 10 as heating steam is connected to the inlet chamber 37. A heater drain pipe 41 for discharging a condensed drain described later is connected to the intermediate chamber 38. The outlet chamber 39 is connected to a drain vent outlet pipe 42 for discharging condensed drain and vent steam described later.

  Further, as shown in FIG. 2, the plurality of heat transfer tubes 31 of the heater 22 include a plurality of heat transfer tubes 31 </ b> A having both ends communicating with the inlet chamber 37 and the intermediate chamber 38, and both ends with the intermediate chamber 38 and the outlet chamber. And a plurality of heat transfer tubes 31 </ b> B communicated with 39. Therefore, the flow of the heating steam flowing through the heat transfer tubes 31A and 31B is configured in four passes.

  That is, the flow of the heating steam that flows out from the inlet chamber 37 and flows through the upper portion of the heat transfer tube 31A becomes the first path A1, and the flow of the heating steam that flows through the lower portion of the heat transfer tube 31A and flows into the intermediate chamber 38 is first. Two passes A2. The flow of the heating steam that flows out from the intermediate chamber 38 and flows through the upper portion of the heat transfer tube 31B becomes the third path A3, and the flow of the heating steam that flows through the lower portion of the heat transfer tube 31B and flows into the outlet chamber 39 is the fourth path. A4.

  Then, as shown in FIG. 5, the condensed drain (water) generated in the second path A2 of the heating steam flows into the intermediate chamber 38 of the heating steam header 32 and then passes through the heater drain pipe 41 to the outside. In other words, as shown in FIG. 1, the water is discharged to a heater drain tank 43 to which the heater drain pipe 41 is connected. The heater drain tank 43 is connected to the feed water heater 44, and the drain in the heater drain tank 43 is guided into the feed water heater 44. As shown in FIG. 5, the heated steam from which condensed drain has been removed in the intermediate chamber 38 of the heated steam header 32 flows from the intermediate chamber 38 to the upstream side portion of the heat transfer pipe 31B, and the third path A3 of the heated steam Become.

  Here, as shown in FIGS. 1 and 5, the heater drain tank 43 is communicated with the intermediate chamber 38 of the heating steam header 32 through a balance pipe 45. The balance pipe 45 balances the pressure in the intermediate chamber 38 and the heater drain tank 43, and the condensed drain in the intermediate chamber 38 is passed through the heater drain pipe 41 into the heater drain tank 43 by the action of gravity. It performs the function of discharging smoothly. Further, the balance pipe 45 is provided with a short pipe 46 that extends upward and opens at an end of the heating steam header 32 in the intermediate chamber 38. This short pipe 46 is designed to prevent the condensed drain in the intermediate chamber 38 from flowing into the balance pipe 45.

  As shown in FIGS. 1 and 6, the one drain vent outlet pipe 42 connected to the outlet chamber 39 of the heating steam header 32 is connected to the inside of the outlet chamber 39 from the fourth path A4 of the heating steam flowing in the heat transfer pipe 31B. Vent steam (including non-condensable gas) and condensed drain that flow into the outside are discharged to the outside of the apparatus, that is, to the feed water heater 44 connected to the drain vent outlet pipe 42 via a drain orifice 47 as a flow rate adjusting mechanism. The drain orifice 47 is disposed in the drain vent outlet pipe 42. During normal operation of the moisture separator / heater 12, the pressure in the heated steam header 32 is higher than that of the feed water heater 44. Therefore, by narrowing the orifice diameter of the drain orifice 47 and limiting the flow rates of the vent steam and condensed drain. The vent steam and the condensate drain in the outlet chamber 39 are maintained at an optimum outflow amount so as not to flow too much into the feed water heater 44.

  Further, the drain vent outlet pipe 42 is connected to the condenser 14, and is connected to the feed water heater 44 or the condenser 14 in a switchable manner by the action of the switching valves 48 and 49. During the normal operation of the moisture separator heater 12, the switching valve 48 is opened, the switching valve 49 is closed, and the drain vent outlet pipe 42 is connected to the feed water heater 44 as described above. On the other hand, when the moisture separator / heater 12 is started, the switching valve 48 is closed and the switching valve 49 is opened, so that the drain vent outlet pipe 42 is connected to the condenser 14. Since the pressure in the heating steam header 32 may be lower than the pressure in the feed water heater 44 when the moisture separator / heater 12 is started, the pressure lower than the pressure in the heating steam header 32 at this time is restored. By connecting the drain vent outlet pipe 42 to the water condenser 14, the vent steam and the condensed drain in the outlet chamber 39 of the heating steam header 32 are surely discharged to the condenser 14.

  With the configuration as described above, the following effects (1) to (8) are achieved according to the present embodiment.

  (1) Since the cycle steam flows in from the cycle steam inlet 18 provided at the bottom of the fuselage 17 and is led to the MS element 21 disposed in the lower region in the fuselage 17, the cycle steam is passed through the narrow region in the fuselage 17. , And the flow rate of the cycle steam from the cycle steam inlet 18 to the MS element 21 can be reduced. In addition, the heater 22 is disposed in a substantially central region in the body 17, and the horizontal width W of the tube bundle of the heat transfer tubes 31 in the heater 22 is increased with respect to the height H, and the tube bundle size W / H is 1.6. Since it was set to <W / H <1.9, the flow velocity of the cycle steam that passes outside the plurality of heat transfer tubes 31 can be reduced. Since the pressure loss of the steam is proportional to the square of the flow velocity, by reducing the flow velocity of the cycle steam as described above, the steam flows into the body 17 from the cycle steam inlet 18, and the MS element 21 and the heater 22 are sequentially turned on. The pressure loss of the flowing cycle steam can be greatly reduced.

  In the two-stage reheat type moisture separator and heater as in Patent Document 2, there is an example in which the heating steam header is arranged in the fuselage, but in the heat transfer tube at a position away from the fuselage central region, the width of the tube bundle is May be smaller. In this case, since the outer space of each heat transfer tube of this tube bundle is inevitably narrow, the flow rate of the cycle steam flowing through this space is increased, and there is a limit to the reduction of pressure loss. On the other hand, in this embodiment, by setting the tube bundle size W / H of the heat transfer tube 31 of the heater 22 to 1.6 <W / H <1.9, the pressure loss of the cycle steam as described above. As a result, the plant efficiency can be improved.

  (2) The cross-under pipe 34 that connects the cycle steam inlet 18 of the moisture separator / heater 12 and the high-pressure steam turbine 11 to guide the cycle steam to the plurality of cycle steam inlets 18 is a branch pipe having a branch portion 34A. For this reason, the flow path cross-sectional area increases at the plurality of branch portions 34A. As a result, since the flow velocity of the cycle steam flowing through the branch portion 34A can be reduced, the pressure loss of the cycle steam from the high-pressure steam turbine 11 to the cycle steam inlet 18 of the moisture separation heater 12 can be greatly reduced. .

  (3) When the flow of the heating steam flowing in the heat transfer tube 31 in the heater 22 is two-pass, in the lower portion of the heat transfer tube 31 where the temperature of the cycle steam flowing outside the heat transfer tube 31 is low, The condensed drain generated inside tends to be supercooled (cooled to a temperature lower than the saturated steam temperature).

  On the other hand, as in the present embodiment, the flow of the heating steam flowing through the heat transfer tube 31 in the heater 22 is configured in four passes, and the condensed drain generated in the second pass A2 of the heating steam is the heating steam header 32. Since it is discharged | emitted from the intermediate | middle chamber 38 through the heater drain pipe | tube 41 outside the apparatus, the vapor | steam amount of the heating steam which flows the inside of the heat exchanger tube 31 (31B) after that is ensured, and a saturated state is hold | maintained. As a result, it is possible to suppress the overcooling of the condensed drain generated particularly in the fourth pass A4 of the heating steam.

  (4) Since the supercooling of the condensed drain generated in the heat transfer tube 31 in the heater 22 is suppressed, a large amount of heat is introduced into the heat transfer tube 31 in the heater 22 of the moisture separation heater 12 in order to reduce this supercooling. It is not necessary to introduce the steam from the steam generator 10 as heating steam. As a result, the amount of steam guided from the steam generator 10 through the heating steam inlet pipe 40 into the inlet chamber 39 of the heating steam header 32 is reduced, and more steam generated by the steam generator 10 can be introduced into the high-pressure steam turbine 11. Therefore, the plant efficiency can be improved accordingly.

  (5) The heater drain tank 43 from which the condensed drain from the intermediate chamber 38 of the heated steam header 32 is discharged via the heater drain pipe 41 and the intermediate chamber 38 are communicated by a balance pipe 45. Therefore, the pressure in the intermediate chamber 38 and the heater drain tank 43 is balanced, and the condensed drain in the intermediate chamber 38 is smoothly discharged through the heater drain pipe 41 into the heater drain tank 43 by the action of gravity. Can be made.

  (6) One drain vent outlet pipe 42 is connected to the outlet chamber 39 of the heating steam header 32, and the vent steam and the condensed drain flowing into the outlet chamber 39 from the heat transfer pipe 31 through this drain vent outlet pipe 42 are heated by feed water. Since it is discharged to the condenser 44 or the condenser 14, the system configuration of the piping can be simplified as compared with the case where the vent steam and the condensed drain are discharged using separate piping.

  (7) The vent steam and the condensed drain that have flowed into the outlet chamber 39 of the heating steam header 32 are discharged to the feed water heater 44 through the drain office 47, and the drain office 47 defines the discharge flow rate of the vent steam and the condensed drain. Configured to be restricted. For this reason, the discharge | emission flow volume to the feed water heater 44 of the vent vapor | steam in the exit chamber 39 and a condensed drain can be maintained optimally.

  (8) Since the drain vent outlet pipe 42 connected to the outlet chamber 39 of the heating steam header 32 is switchably connected to the feed water heater 44 and the condenser 14, the pressure in the heating steam header 32 is changed to the feed water heater. By connecting the drain vent outlet pipe 42 to the condenser 14 at the start of the moisture separation heater 12 that is lower than the inside of the condenser 44, the pressure in the heating steam header 32 at this time is lowered into the condenser 14. The vent vapor and the condensed drain containing the non-condensable gas in the outlet chamber 39 can be reliably discharged.

[B] Second embodiment (FIGS. 11 to 13)
FIG. 11 is a longitudinal sectional view showing a second embodiment of the moisture separation heater according to the present invention. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description is simplified or omitted.

  The difference between the moisture separation heater 50 of the present embodiment and the previous embodiment is that the second MS drain port 20 is omitted from the bottom of the body 17 and the MS drain discharge portion 51 is replaced with the first MS drain port 19. Is installed at the bottom of the body 17, and an MS drain tank 52 that functions in the same manner as the MS drain tank 28 is directly attached to the bottom of the body 17.

  The MS drain discharge part 51 is attached at a position farther than the MS drain tank 50 across the cycle steam inlet 18 at the bottom of the body 17. As shown in FIGS. 12 and 13, the MS drain discharge portion 51 allows moisture (water) separated by passing through the MS element 21 to pass through the MS element support member 53 to serve as a pressure adjustment mechanism. It is guided as drain into the discharge unit main body 55 through the U seal 54, and moisture (water) separated before passing through the MS element 21 and flowing down to the bottom of the body 17 is directly guided to the discharge unit main body 55 as drain. It is.

  Since the pressure in the MS element support member 53 is slightly lower than that in the body 17, the U-seal 54 is installed in consideration of this pressure difference, and the tubular member communicated with the MS element support member 53. 56 and a receiving member 57 disposed in the discharge portion main body 55 immediately below the cylindrical member 56. The lower end of the cylindrical member 56 is positioned near the bottom surface of the receiving member 57. Moisture (drain) separated through the MS element 21 and flowing down in the MS element support member 53 passes through the cylindrical member 56 and is temporarily stored in the receiving member 57, and then from the upper edge of the receiving member 57. The discharge body 55 overflows. The drain (water) stored in the receiving member 57 discharges the drain in the MS element support member 53 even when the pressure in the MS element support member 53 is lower than the pressure in the discharge portion main body 55. It is possible to guide the inside of the body 55.

  On the other hand, as shown in FIG. 11, the MS drain tank 52 is also provided with a U seal 54 inside, and moisture separated through the MS element 21 is discharged into the MS drain tank 52 through the U seal 54. The moisture separated before passing through the MS element 21 is directly discharged into the MS drain tank 52. Further, the discharge part main body 55 of the MS drain discharge part 51 is communicated with the MS drain tank 52 using a drain communication pipe 58. For this reason, the drain led into the discharge section main body 55 is discharged into the MS drain tank 52 through the drain communication pipe 58.

  Therefore, according to the present embodiment, in addition to the same effects as the effects (1) to (8) of the above embodiment, the following effect (9) is achieved.

  (9) The MS drain tank 52 is directly attached to the bottom of the body 17, and the MS seal tank 52 and the MS drain discharge portion 51 each have a U seal 54 as a pressure adjusting mechanism. Therefore, in the case of the MS drain tank 52, the moisture separated through the MS element 21 is discharged into the MS drain tank 52 through the U seal 54, and the moisture separated before passing through the MS element 21 is discharged. Is directly introduced into the MS drain tank 52. In the case of the MS drain discharge part 51, the moisture separated through the MS element 21 is guided to the discharge part main body 55 through the U seal 54, and the moisture separated before passing through the MS element 21 is removed. Directly leading to the discharge unit main body 55, moisture (drain) in the discharge unit main body 55 is discharged to the MS drain tank 52 through the drain communication pipe 58.

  Thus, the low-pressure moisture separated through the MS element 21 and the high-pressure moisture separated before passing through the MS element 21 can be discharged to the MS drain tank 52 without passing through the piping. Moreover, since it can discharge | emit into the MS drain tank 52 from the MS drain discharge part 51 via the drain communication pipe | tube 58, the moisture separation heater 50 and its piping system can be simplified.

The system diagram which shows 1st Embodiment in the moisture separation heater which concerns on this invention with a piping system. The longitudinal cross-sectional view which shows the moisture separation heater of FIG. Sectional drawing which follows the III-III line | wire of FIG. FIG. 4 is an IV perspective view of FIG. 2. Sectional drawing which follows the VV line of FIG. Sectional drawing which follows the VI-VI line of FIG. The front view which shows the heating steam header of FIG. 2 with a fuselage | body. The graph which shows the relationship between tube bundle size W / H of the heat exchanger tube of FIG. 2, and pressure loss (DELTA) P of the cycle steam which flows the outer side of a heat exchanger tube. The graph which shows the relationship between the heating steam header diameter ratio d / D of FIG. 7, and the tube bundle size W / H of a heat exchanger tube. The graph which shows the relationship between heating steam header length ratio 1 / D of FIG. 7, and the tube bundle size W / H of a heat exchanger tube. The longitudinal cross-sectional view which shows 2nd Embodiment in the moisture separation heater which concerns on this invention. Sectional drawing which shows the drain discharge part of FIG. Sectional drawing which follows the XIII-XIII line | wire of FIG. The longitudinal cross-sectional view which shows the conventional moisture separation heater. Sectional drawing which follows the XV-XV line | wire of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 High pressure steam turbine 12 Moisture separation heater 17 Body 18 Cycle steam inlet 21 MS element 22 Heater 31 Heat transfer pipe 32 Heated steam header 34 Cross under pipe 34A Branch part 37 Outlet room 38 Intermediate room 39 Outlet room 40 Heating steam inlet pipe 41 Heater drain pipe 42 Drain vent outlet pipe 43 Heater drain tank 45 Balance pipe 47 Drain office 48, 49 Switching valve 50 Moisture separation heater 51 MS drain discharge part 52 MS drain tank 54 U seal (pressure adjustment mechanism)
58 Drain communication pipe A1 1st pass A2 2nd pass A3 3rd pass A4 4th pass W Width H Height W / H Tube bundle size ΔP Pressure loss

Claims (10)

The torso,
A cycle steam inlet provided at the bottom of the fuselage for introducing cycle steam into the fuselage;
A moisture separating element that is inclinedly disposed in a lower region within the fuselage and separates moisture in cycle steam;
A one-stage reheat type having a plurality of heat transfer tubes arranged in a substantially central region within the fuselage and flowing a heating steam, and a heater having a single heating steam header communicating with these heat transfer tubes. A moisture separator heater of
When the width of the tube bundle in the plurality of heat transfer tubes is W and the height is H, the tube bundle size W / H is
[Equation 1]
1.6 <W / H <1.9
The moisture separator heater is characterized in that the heating steam header is configured in a horizontally placed cylindrical shape. The flow of the heating steam flowing through the heat transfer pipe is configured in four passes, and the heating steam header has an inlet chamber through which the first path of heating steam flows out, and a second path of heating steam flows into the third path. Is divided into an intermediate chamber into which the gas flows out and an outlet chamber into which the fourth path of the heated steam flows,
2. The moisture separation heating according to claim 1, wherein the condensed drain that is generated in the second pass of the heated steam and flows into the intermediate chamber is discharged to the outside through the heater drain pipe. vessel. The heater drain pipe is connected to a heater drain tank, and the heater drain tank communicates with an intermediate chamber of a heating steam header via a balance pipe. Moisture separator heater. A drain vent outlet pipe is connected to the outlet chamber of the heated steam header, and vent steam and condensed drain that have flowed into the outlet chamber from the fourth pass of the heated steam are discharged from the drain vent outlet pipe to the outside through the outlet chamber. The moisture separator / heater according to claim 2, wherein the moisture separator / heater is configured as described above. A plurality of the cycle steam inlets are provided at the bottom of the fuselage, and a branch cross-under pipe is connected to these cycle steam inlets, and a plurality of cycle steams from the high-pressure turbine are passed through the cross-under pipe. The moisture separator heater according to claim 1, wherein the moisture separator heater is configured to be introduced into the cycle steam inlet. The moisture separation heater according to claim 4, wherein the drain vent outlet pipe is connected to a feed water heater via a flow rate adjusting mechanism. The moisture separator / heater according to claim 4, wherein the drain vent outlet pipe is switchably connected to a feed water heater and a condenser. A drain tank is attached to the bottom of the fuselage, the drain separated before passing through the moisture separating element is directly discharged into the drain tank, and the drain separated through the moisture separating element is a pressure adjusting mechanism. The moisture separator / heater according to claim 1, wherein the moisture separator / heater is configured to be discharged into the drain tank. A drain discharge portion is attached to the bottom of the body, and the drain discharge portion communicates with the drain tank through the drain communication pipe and has a pressure adjusting mechanism, and drains separated before passing through the moisture separation element are communicated with the drain. It is configured to guide the drain through the pipe into the drain tank and guide the drain separated through the moisture separation element into the drain tank through a pressure adjusting mechanism and a drain communication pipe. Item 9. The moisture separation heater according to Item 8. The moisture separation heater according to claim 8 or 9, wherein the pressure adjusting mechanism is a U seal.

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