US3923009A

US3923009A - Moisture separating and steam reheating apparatus

Info

Publication number: US3923009A
Application number: US441798A
Authority: US
Inventors: Akio Sohma
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1973-02-12
Filing date: 1974-02-12
Publication date: 1975-12-02
Anticipated expiration: 1992-12-02
Also published as: JPS5143525B2; JPS504401A; CA977639A

Abstract

This invention provides a moisture separating and steam reheating apparatus having a tubular shell structure, a rectifying device for moist steam, a moisture separator and a steam reheater disposed in parallel to each other in the shell structure, a plurality of steam inlets mounted on a side wall of the shell structure and a plurality of steam outlets formed on another opposite side wall of said shell structure, so that steam can flow substantially straight in the horizontal direction in the shell structure from the inlets to the outlets to remove moisture in the steam and to be reheated at a superheated temperature at a low pressure loss of the actuating steam.

Description

Dec. 2, 1975 United States Patent [191 Sohma 3,750,371 8/1973 Gutman.......................... 122/483 X 1 1 MOISTURE SEPARATING AND STEAM REHEATING APPARATUS Primary Examiner-Kenneth W. Sprague Attorney, Agent, or FirmThomas E. Bcall, Jr.

D n WP in 1 e h HT. mm L oi Sh mu AH mn m fi mA MN 77 [57] ABSTRACT This invention provides a moisture separating and [22] Filed: Feb. 12, 1974 21 Appl. No.: 441,798

steam reheating apparatus having a tubular shell structure, a rectifying device for moist steam, a moisture [30] Foreign Application Priority Data Feb, 12, 1973 [52] U.S. 122/34; 122/483 [51] Int. F22b l/06 122/32, 33, 34, 483

site side wall of said shell structure, so that steam can flow substantially straight in the horizontal direction in Field of Search [56] References Cited the shell structure from the inlets to the outlets to re- UNTED STATES PATENTS move moisture in the steam and to be reheated at a superheated temperature at a low pressure loss of the actuating steam.

122/483 Carnavos et al. 122/483 12 Claims, 6 Drawing Figures Ritland m t e h b b u H 23 777 999 HHH 66 002 037 372 96 333 Sheet 1 0f 2 3,923,009

US. Patent Dec. 2, 1975 FIG.

FIG. 2

US. Patent Dec. 2; 1975 Sheet2 0f2 3,923,009

MOISTURE SEPARATING AND STEAM REHEATING APPARATUS BACKGROUND OF THE INVENTION The present invention relates to moisture separating and steam reheating apparatus adapted to reheat actuating steam after moisture has been separated therefrom, especially to a moisture separating and steam reheating apparatus that can be assembled in an atomic power plant containing a steam turbine plant.

Since steam generated by atomic reactors is in a saturated condition or a slightly superheated condition, moisture in the steam increases during the process of expanding the steam in a steam turbine. Such moisture content is not desirable with respect to heat efficiency of the turbine power plant and the security thereof. Therefore, many methods are employed for removal of the moisture from the moist steam. It is well known that a moisture separator may be disposed within a communicating conduit between a high pressure turbine and a low pressure turbine to remove the moisture in the steam, and further that a steam reheater may be connected with the moisture separator to reheat the steam by using high temperature steam as the heat exchange fluid, which can be obtained as main steam or the like. Thereby, the corrosion of the parts in the low pressure turbine may decrease and the heat efficiency of the low temperature turbine may rise, in correlation with the removal of moisture and reheating of the steam.

In the prior art, it is known to combine a moisture separator with a steam reheater in a tubular shell. This apparatus has long passages for the steam in the shell, which produces a proportionately large pressure loss, which pressure loss correspondingly reduces the heat efficiency of the turbine power plant.

As an example of such prior art, an apparatus may include an elongated tubular shell structure, an elongated moisture separator disposed in the tube shell structure, a moisture/steam collection space and a steam collection space, a steam inlet disposed on an end closure member of said tubular shell and communicating with said moisture/steam collection space, a steam outlet communicating with said steam collection space, a moisture drain outlet communicating with said moisture/steam collection space, a steam reheater disposed in said steam collection space and including a plurality of elongated tubes.

However, since the steam inlet is mounted on the end closure member of the shell, the pressure loss of steam will effectively become quite large in the shell structure due to the length of travel.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a moisture separating and steam reheating apparatus, which will cause the moist steam to be processed to flow from an inlet to an outlet substantially in a straight path, thereby to make the pressure loss of actuating steam smaller than in the prior art.

Another object of the present invention is to provide a moisture separating and steam reheating apparatus that will have a plurality of steam inlets and outlets permitting this straight flow across the shell structure. The present invention will treat a large quantity of moist steam at a high efficiency without increasing the dimensions of the shell, with respect to the prior art. Thus, actuating steam may be expanded through turbines without a high concentration of moisture that would be harmful to the steam turbines, while at the same time keeping the pressure loss of the actuating steam small.

The above objects are accomplished by providing a moisture separator and steam reheater that comprises an elongated tubular shell with closure members, a plurality of moist actuating steam inlets having their flow axes extending radially through one side wall of the shell, a plurality of reheated actuating steam outlets being mounted on the opposite side wall of the shell with their flow axes extending radially opposite from the inlet flow axes, flow distribution or rectifying means substantially elongated from one closure member to another closure member and disposed adjacent and in parallel with the row of inlets, a moisture separator adjacent to and in parallel with the rectifying means along a major portion of the length thereof, said moisture separator dividing the interior of the shell into a moisture/steam collection space and a steam collection space, a steam reheater disposed in said steam collection space and including a plurality of elongated tubes extending in parallel to said moisture separator and along a major portion of the length thereof, whereby the steam supplied from the inlets flows substantially in a straight line to the outlets and the lines of steam cross at right angles with the heat exchange fluid within the reheater tubes.

BRIEF DESCRIPTION OF THE DRAWING Further objects, features and advantages of the present invention will become more clear from the following detailed description of a preferred embodiment of the present invention, as shown in the attached drawing, wherein:

FIG. 1 is a schematic view of an overall steam power plant system employing the present invention;

FIG. 2 is a perspective view, with portions broken away and in cross section, of the moisture separator and steam reheater apparatus according to the present invention; 7

FIG. 3 is a longitudinal cross sectional view along the axis of the device of FIG. 2;

FIG. 4 is a transverse cross sectional view taken on line IV-IV of FIG. 3;

FIG. 5 is an enlarged view of a part of the moisture separator showing the plurality of wavy plates contained therein; and

FIG. 6 is a perspective view of one of the wavy plate blocks for the moisture separator, with portions broken away.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A system, shown schematically, of a steam power plant employing the moisture separating and reheating apparatus of the present invention is shown in FIG. 1. In such a steam power plant system, for example an atomic power turbine plant, main actuating steam from a reactor is provided in a nearly saturated condition to be fed into line 66 to a high pressure turbine 60, and after traveling through and expanding in the high pressure turbine 60, the exhaust steam will exit through line 70 with a large amount of moisture. The moisture within the steam exhausted from the high pressure turbine 60 will be removed in the moisture'separator 62, with the condensate being removed by a drain conduit 67. After the moisture has been removed by separator 62, the actuating steam will pass into first and

second reheaters

63, 64, where the actuating steam will be heated to become superheated steam to pass into the outlet conduit 71 for delivery to the low pressure turbine 61. To use as a heat exchange fluid for reheating the actuating steam within the

reheaters

63, 64, steam may be extracted from the high pressure turbine 60 at a midpoint in the expansion by means of conduit 65, or steam may be obtained from the main steam inlet conduit 66. After the heat exchange steam from

lines

65, 66 passes through the

reheaters

63, 64, it will be exhausted as moist steam or condensate from

drain conduits

68, 69, respectively.

The apparatus that is the particular subject matter of the present invention is used in the overall system of FIG. 1 as the steam separator 62 and the

reheaters

63, 64. The apparatus of the present invention is shown in detail in FIG. 2 as a unit 10, for removing moisture from the moisture laden, saturated steam, for example vapor steam, in a highly pressurized state and heating the demoisturized steam to a dry and/or superheated state. This type of apparatus is generally known in the art and is usually called a unitary moisture separator and steam reheater apparatus. For simplicity of explanation, the above term will be used in this specification, and also steam and water will be employed in the description of the moisture separator and steam reheater apparatus for the same reason, and not by way of limitation.

As shown in FIGS. 2 and 3, the moisture separating and steam reheating apparatus of the present invention is provided with a horizontally disposed and axially elongated tubular shell or casing 11, which is closed at its opposite axial ends by a pair of oppositely disposed end caps or

closures

50, 51, and is further provided with a plurality of steam inlets 12 that extend through and are mounted on the side cylindrical wall 52 and a plurality of steam outlets 13 that extend through and are mounted on the opposite, side cylindrical wall 53. Mounted within the shell 1 1 so as to face the steam inlets 12, is a rectifying or flow directing device 14, which is comprised of a plurality of rectifying plates to distribute the quantity of steam flow evenly along any position of the rectifying device, which is preferably disposed in a vertical plane perpendicular to the flow path of the inlets 12. Immediately downstream of the rectifying device 14, there is mounted a moisture separator 15 of a wave plate type, and downstream from the moisture separator 15, there are provided, serially, first and

second reheaters

16, 17. Each of the

reheaters

16 and 17 includes a heat exchanger of the parallel tube type, with the tubes extending generally between the

end closures

50, 51. The moisture separator 15 will divide the interior into a moist steam chamber adjacent the inlets l2 and a steam chamber on the side of the outlets 13, with the

reheaters

16, 17 being within this steam chamber.

The interior is further divided by means of oppositely disposed

partitions

24, 25, which will support the opposite axial ends of the rectifying device 14, the moisture separator 15, and the

reheaters

16, 17. When the length of the shell is relatively long, it is desirable to employ a divided structure for the rectifying device 14 and further to provide a dividing structure for the moisture separator 15, to facilitate their assembly.

With respect to the moisture separator 15, its construction is shown as in FIG. to be made of a plurality of wave plates a that are assembled as shown in FIG.

4 6 within a frame 36 to provide a block. A plurality of these blocks (five being shown in the drawing) are arranged in axially spaced and axially aligned position within the shell as illustrated in FIG. 3. The rectifier unit is correspondingly divided into a plurality of individual blocks.

To provide heat exchange fluid to the first and

second reheaters

16, 17, there are respectively provided

headers

18, 19. Heat exchange steam is provided, as shown in FIG. 2, through

inlets conduits

20, 21 to the

headers

18, 19 for distribution to the

reheaters

16, 17, respectively. As seen, the plurality of tubes that form the

reheaters

16, 17 extend from the upper portion of the

headers

18, 19 horizontally in parallel spaced relationship to the opposite end of the shell, where they are bent with return portions so as to extend axially and parallel back to the

headers

18, 19. Thus, the heat exchange fluid is returned to the lower portions of the

headers

18, 19, and any condensate in the returned heat exchange fluid is conducted through

drain conduits

22, 23 that are respectively connected to the lower return portions of the

headers

18, 19.

The inlet and outlet terminal ends of the heat exchange tubes of U-type are mounted in and supported by a partition 34 that closes the end of the

headers

18, 19. The return bend portions of the heat exchange tubes are mounted in and supported by the partition 25, and the center portions of these tubes are mounted and supported on partition plates 30 that are provided in axial spaced relationship throughout the length of the shell 11 as desired, whereby deflection and vibration of the tubes are prevented. As illustrated in FIG. 4,

plates

26 and 27 are horizontally disposed in the shell 11 so that they will hold the upper and lower portions of the

reheaters

16, 17, the rectifying device 14, the moisture separator 15 and the

partitions

24, 25, 30, respectively.

A drain receptacle 28, as shown in FIG. 4, is mounted in the lower surface of the plate 27 and a conduit 29 is connected to the drain receptacle 28 so as to discharge condensed liquids to the exterior of the shell 11.

As illustrated in FIG. 2, the header 18 is divided into a steam chamber 32 and a water chamber 33 by means of a partition 35, which partition will prevent direct communication between the two chambers. The water chamber 33 is provided with a water drain conduit 22. The header 19 has a substantially identical construction to the header 18.

Vertically disposed outlet baffle plates 31 are mounted within the shell 1 1 so that they face the row of outlets 13 to distribute the flow of steam from the reheaters so as to obtain an even distribution of steam through the reheaters.

During operation, steam from the high pressure turbine 60 will flow through the conduit 70, with respect to the overall system of FIG. 1, to be delivered through steam inlets 12 into the shell 11 of FIG. 2, in a substantially horizontal direction transverse to the axis of the shell 11. The incoming steam from inlets 12 will be evenly distributed by the rectifying device 14, so that substantially uniform streams of steam will enter the moisture separator 15, which can therefore uniformly remove moisture from the streams throughout its elongated length. The removed moisture or condensate will drop from the plates of the separator 15 and gather at the drain receptacle 28 to be drained through the conduit 29. After the moisture has been removed from the actuating steam, the steam will enter into the first and

second reheaters

16, 17 to be reheated as they cross the entire structure of the reheaters 1'6, 17. The heat exchange fluid, particularly steam, that is provided within the tubes of the reheaters 16 17 will be conductedto the steam chamber 32 of header l8v by inlet conduit 20, and then will flow in a U-shape through the tubes of the reheater 16 to return to the water chamber 33. From the water chamber 33, any remaining steam will flow out of the outlet conduit 27, and that portion of the heat exchange steam that hasbeen condensed will flow as water through the drain conduit 22. The second re-' heater 17 has the same function and a similar operation as the above described first reheater 16. Q

As above described in detail, a plurality of steam-inlets 12 and a plurality of steam'outlets 13 are respectively disposed on

opposite side walls

52, 53 of the shell 11 in aligned positions with the rectifying 'device 14;

the moisture separator 15, and the

reheaters

16, 17 therebetween, that is sequentially arranged between the inlets and outlets and vertically disposed in the shell so that the actuating steam can flow substantially in a straight line from the inlets 12 to the outlets 13 in the shell.

While a preferred embodiment of the present invention has been described in detail with respect to the drawing for purposes of illustration and the specific advantages of the details, further embodiments, variations and modifications are contemplated according to the broader aspects of the present invention, all as defined by the spirit and scope of the following claims.

What is claimed is:

1. A unitary moisture separating and steam reheating apparatus, comprising: an axially elongated tubular shell structure having a pair of oppositely disposed end closure members; a plurality of steam inlets formed on a side wall of the shell structure; a plurality of steam outlets formed on another horizontally opposite side wall of the shell structure; flow rectifying means axially extending substantially from one of said end closure members to the other of said end closure members and being disposed vertically in the vicinity of the inlets for distributing the inlet steam along the length of said shell structure; moisture separator means extending vertically and in parallel to said flow rectifying means along a major portion of the length thereof for removing moisture from the steam; steam reheater means extending vertically and in parallel to said moisture separator means along a major portion of the length therefor for heating the steam; said steam reheater means being disposed between said moisture separator means and said steam .outlets, and including a plurality of longitudinally elongated heat exchange tubes; said steam inlets, rectifying means, moisture separator means, steam reheater means, and steam outlets being serially mounted horizontally across a diameter of said tubular shell structure so that the steam flows substantially horizontally and straight from said steam inlets toward said steam outlets to pass through said vertically disposed flow rectifying means, said vertically disposed moisture separator means and said vertically disposed steam reheater means at substantially right angles.

2. A unitary moisture separating and steam reheating apparatus, comprising: an axially elongated tubular shell structure having a pair of oppositely disposed end closure members; a plurality of steam inlets formed on a side wall of the shell structure; a plurality of steam outlets formed on another side wall of the shell structure; flow rectifying means axially extending substantiallyfrom one of said, end closure' membe'rs to the otherof said end closure members andbeing disposed in the vicinityvof the inlets for distributing the inlet steam along the length of said shell structure; moisture separator means extending in parallel to said flow rectif fying means along amajor portion of the length thereof for removing moisutre from the steam; steam reheater means extending in parallel to. said moisture separator meansalong a major portion of the length therefor for heating the steam; said steam reheater means being disposed between said moisture separator means and said steam outlets, and including a plurality of longitudinally'elongated heatexchange tubes; said steam inlets, rectifying means, moisture separator means, steam reheater means, and steam outlets being seriallymounted so that the steam flows substantially straight from said steam inlets toward said steam outlets to pass through said moisture separator means and said steam reheater means at substantially right angles; and a plurality of baffle plates disposed between said steam reheater means and said steam outlets.

3. A unitary moisture separating and steam reheating apparatus as claimed in claim 2, wherein said baffle plates correspond in number to the number of said steam outlets, and are respectively immediately transversely adjacent to said steam outlets; each of said baffle plates extending parallel to said rectifying means, said moisture separator means, and said steam reheater means.

4. A unitary moisture separating and steam reheating apparatus as claimed in claim 1, wherein said moisture separator means comprises a plurality of blocks extending in the axial direction, each of which comprises a frame and a plurality of wave plates assembled in the frame.

5. A unitary moisture separating and steam reheating apparatus as claimed in claim 4, wherein said blocks are substantially identical to each other and serially axially aligned with each other; and said rectifying means including a corresponding number of separate coextensive blocks of parallel rectifier plates.

6. A unitary moisture separating and steam reheating apparatus as claimed in claim 1, including a plurality of partitions supporting said tubes and being mounted in the shell structure in axially spaced relation.

7. A unitary moisture separating and steam reheating apparatus as claimed in claim 6, wherein each of said partitions is substantially planar and extends perpendicular to said rectifying means, said moisture separator means, and said steam reheater means.

8. A unitary moisture separating and steam reheating apparatus as claimed in claim 1, wherein said steam reheater means includes a header which is fluid connected to the tubes and has partition means dividing its interior into a steam chamber and a separate water chamber, a steam inlet conduit fluid connected to the steam chamber, and a steam outlet conduit and a condensate drain conduit fluid connected to the water chamber.

9. A unitary moisture separating and steam reheating apparatus as claimed in claim 8, wherein said tubes extend in parallel relationship from one terminal end at said steam chamber axially for substantially the entire length of said shell structure, are reversely bent at the end of said shell structure opposite from said header, and extend parallel to each other back to their opposite terminal ends at said water chamber.

10. A unitary moisture separating and'steam reheating apparatus, comprising: an axially elongated tubular shell structure having a pair of oppositely disposed end closure members; a pair of transverse partitions respectively oppositely disposed adjacent each of said end closure members; a plurality of steam inlets formed on a side wall of the shell structure; a plurality of steam outlets formed on another side wall of the shell structure; flow rectifying means axially extending from one of said partitions to the other partition and being disposed adjacent to the inlets for distributing the inlet steam along the length of said shell structure; moisture separator means extending in parallel to said flow rectifying means along said flow rectifying means from said one partition to said other partition for removing moisture from the steam; steam reheater means extending in parallel to said moisture separator means and along said moisture separator for heating the steam; said steam reheater means being disposed between said moisture separator means and said steam outlets, and including a plurality of longitudinally elongated heat exchanger tubes supported by said partitions, and a pair of partitions horizontally disposed respectively on an upper portion and a lower portion of said moisture separator means and said steam reheater means.

11. A unitary moisture separating and steam reheating apparatus as claimed in claim 10, including a header mounted on said lower partition, fluid communicating with said moisture separator means and connected to a condensate drain conduit.

12. A unitary moisture separating and steam reheating apparatus as claimed in claim 11, wherein a plurality of baffle plates are disposed between said steam reheater means and said steam outlets.

Claims

1. A unitary moisture separating and steam reheating apparatus, comprising: an axially elongated tubular shell structure having a pair of oppositely disposed end closure members; a plurality of steam inlets formed on a side wall of the shell structure; a plurality of steam outlets formed on another horizontally opposite side wall of the shell structure; flow rectifying means axially extending substantially from one of said end closure members to the other of said end closure members and being disposed vertically in the vicinity of the inlets for distributing the inlet steam along the length of said shell structure; moisture separator means extending vertically and in parallel to said flow rectifying means along a major portion of the length thereof for removing moisture from the steam; steam reheater means extending vertically and in parallel to said moisture separator means along a major portion of the length therefor for heating the steam; said steam reheater means being disposed between said moisture separator means and said steam outlets, and including a plurality of longitudinally elongated heat exchange tubes; said steam inlets, rectifying means, moisture separator means, steam reheater means, and steam outlets being serially mounted horizontally across a diameter of said tubular shell structure so that the steam flows substantially horizontally and straight from said steam inlets toward said steam outlets to pass through said vertically disposed flow rectifying means, said vertically disposed moisture separator means and said vertically disposed steam reheater means at substantially right angles.

2. A unitary moisture separating and steam reheating apparatus, comprising: an axially elongated tubular shell structure having a pair of oppositely disposed end closure members; a plurality of steam inlets formed on a side wall of the shell structure; a plurality of steam outlets formed on another side wall of the shell structure; flow rectifying means axially extending substantially from one of said end closure members to the other of said end closure members and being disposed in the vicinity of the inlets for distributing the inlet steam along the length of said shell structure; moisture separator means extending in parallel to said flow rectifying means along a major portion of the length thereof for removing moisutre from the steam; steam reheater means extending in parallel to said moisture separator means along a major portion of the length therefor for heating the steam; said steam reheater means being disposed between said moisture separator means and said steam outlets, and including a plurality of longitudinally elongated heat exchange tubes; said steam inlets, rectifying means, moisture separator means, steam reheater means, and steam outlets being serially mounted so that the steam flows substantially straight from said steam inlets toward said steam outlets to pass through said moisture separator means and said steam reheater means at substantially right angles; and a plurality of baffle plates disposed between said steam reheater means and said steam outlets.

10. A unitary moisture separating and steam reheating apparatus, comprising: an axially elongated tubular shell structure having a pair of oppositely disposed end closure members; a pair of transverse partitions respectively oppositely disposed adjacent each of said end closure members; a plurality of steam inlets formed on a side wall of the shell structure; a plurality of steam outlets formed on another side wall of the shell structure; flow rectifying means axially extending from one of said partitions to the other partition and being disposed adjacent to the inlets for distributing the inlet steam along the length of said shell structure; moisture separator means extending in parallel to said flow rectifying means along said flow rectifying means from said one partition to said other partition for removing moisture from the steam; steam reheater means extending in parallel to said moisture separator means and along said moisture separator for heating the steam; said steam reheater means being disposed between said moisture separator means and said steam outlets, and including a plurality of longitudinally elongated heat exchanger tubes supported by said partitions, and a pair of partitions horizontally disposed respectively on an upper portion and a lower portion of said moisture separator means and said steam reheater means.