U.S. patent application number 12/353716 was filed with the patent office on 2009-07-16 for heat exchanger.
Invention is credited to Melvin J. Albrecht, Jason M. Marshall, Dennis R. Shiffer, William J. White.
Application Number | 20090178779 12/353716 |
Document ID | / |
Family ID | 40849655 |
Filed Date | 2009-07-16 |
United States Patent
Application |
20090178779 |
Kind Code |
A1 |
White; William J. ; et
al. |
July 16, 2009 |
HEAT EXCHANGER
Abstract
A heat exchanger having an arrangement of heat transfer surfaces
and a pair of vertical steam/water separators structurally
interconnected to one another to provide an integral support
structure for the heat exchanger. The structural interconnection
includes upper and lower structural members extending between the
pair of vertical steam/water separators. The upper and lower
structural members include headers, and an arrangement of heating
surface which extends between and is fluidically connected to the
headers. A structural support framework surrounds the heat
exchanger for bottom support thereof, the framework providing
structural support and rigidity for the heat exchanger and a means
by which the heat exchanger can be picked up and lifted for
placement at a desired location.
Inventors: |
White; William J.;
(Massillon, OH) ; Albrecht; Melvin J.; (Knox TWP,
OH) ; Marshall; Jason M.; (Wadsworth, OH) ;
Shiffer; Dennis R.; (Lawrence TWP, OH) |
Correspondence
Address: |
BABCOCK & WILCOX POWER GENERATION GROUP, INC.
PATENT DEPARTMENT, 20 SOUTH VAN BUREN AVENUE
BARBERTON
OH
44203
US
|
Family ID: |
40849655 |
Appl. No.: |
12/353716 |
Filed: |
January 14, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61020882 |
Jan 14, 2008 |
|
|
|
Current U.S.
Class: |
165/47 |
Current CPC
Class: |
F22B 37/242 20130101;
F22B 29/023 20130101; F28D 1/0426 20130101; F28D 1/0417 20130101;
F28D 1/05316 20130101; F28F 9/001 20130101; F22B 21/20 20130101;
F22B 37/20 20130101 |
Class at
Publication: |
165/47 |
International
Class: |
F28F 9/00 20060101
F28F009/00 |
Claims
1. A heat exchanger comprising an arrangement of heat transfer
surfaces and a pair of vertical steam/water separators structurally
interconnected to one another and providing an integral support
structure for at least a portion of the heat transfer surfaces of
the heat exchanger.
2. The heat exchanger of claim 1, wherein the structural
interconnection includes upper and lower structural members
extending between the vertical steam/water separators.
3. The heat exchanger of claim 2, wherein the upper and lower
structural members are formed of heavy wall pipe.
4. The heat exchanger of claim 3, including a pair of spaced
partition walls disposed in crosswise fashion within the heavy wall
pipe to form a central portion therein.
5. The heat exchanger of claim 4, wherein the central portion is a
header.
6. The heat exchanger of claim 5, wherein said portion of the heat
transfer surfaces extends between and is fluidically connected to
the headers of the upper and lower structural members.
7. The heat exchanger of claim 1, including a support structural
framework having a top, a bottom and opposing lengthwise sides
surrounding the heat exchanger for bottom support thereof.
8. The heat exchanger of claim 7, wherein the structural framework
is in a shape of a rectangular parallelepiped.
9. The heat exchanger of claim 7, wherein the bottom of the
structural framework is comprised of horizontally extending lateral
and longitudinal beams.
10. The heat exchanger of claim 9, wherein the lateral and
longitudinal beams intersect one another to form a grid-like
structure.
11. The heat exchanger of claim 10, including a lattice of
obliquely-disposed web members positioned between intersecting
longitudinal and lateral beams.
12. The heat exchanger of claim 9, wherein the bottom of the
structural framework includes four parallel spaced longitudinal
beams
13. The heat exchanger of claim 12, including two pairs of parallel
spaced lateral braces intersecting the inner two of said four
longitudinal beams to form support bases for the steam/water
separators.
14. The heat exchanger of claim 13, wherein each of the vertical
steam/water separators includes a plurality of pedestal feet
positioned at the lower end of the separator and fixedly secured to
a respective one of the support bases.
15. The heat exchanger of claim 7, wherein each of the opposing
lengthwise sides of the structural framework has two pairs of
parallel spaced vertical beams located at opposite ends of the
structural framework and one pair of parallel spaced longitudinal
beams intersecting the vertical beams and located at the upper end
of each of the opposing sides.
16. The heat exchanger of claim 15, including a lattice of
obliquely-disposed web members positioned between each pair of
vertical beams and the pair of longitudinal beams.
17. The heat exchanger of claim 7, wherein the top of the
structural framework is comprised of two lateral beams intersecting
the upper one of said pair of parallel spaced beams.
18. The heat exchanger of claim 17, wherein the two lateral beams
are located above the heat exchanger and provide the means by which
the heat exchanger and the structural framework can be lifted for
placement at a desired location.
19. In combination, a heat exchanger and the structural framework
for the support thereof, the combination comprising an arrangement
of heat transfer surfaces and a pair of vertical steam/water
separators structurally interconnected to one another and providing
an integral support structure for at least a portion of the heat
transfer surfaces, the structural framework having a top, a bottom,
and opposing lengthwise sides surrounding the heat exchanger for
bottom support thereof.
20. The combination of claim 19, wherein the structural
interconnection is comprised of upper and lower heavy wall pipes,
each pipe having partitions therein defining a central header.
21. The combination of claim 20, wherein said portion of the heat
transfer surfaces extends between and is fluidically connected to
the headers in the upper and lower pipes.
22. The combination of claim 19, wherein the bottom of the
structural framework is comprised of horizontally extending lateral
and longitudinal beams intersecting one another to form a grid-like
structure.
23. The combination of claim 22, including a lattice of
obliquely-disposed web members positioned between intersecting
longitudinal and lateral beams.
24. The combination of claim 22, wherein the bottom of the
structural framework includes four parallel spaced longitudinal
beams.
25. The combination of claim 24, including two pairs of parallel
spaced braces intersecting the inner two of said four longitudinal
beams to form support bases for the steam/water separators.
26. The combination of claim 25, wherein each of the vertical
steam/water separators includes a plurality of pedestal feet
positioned at the lower end of the separator and fixedly secured to
the respective one of the support bases.
27. The combination of claim 19, wherein each of the opposing
lengthwise sides of the structural framework has two pairs of
parallel spaced vertical beams located at opposite ends of the
structural framework and one pair of parallel spaced longitudinal
beams intersecting the vertical beams and located at the upper end
of each of the opposing sides.
28. The combination of claim 27, including a lattice of
obliquely-disposed web members positioned between each pair of
vertical beams and the pair of longitudinal beams.
29. The combination of claim 19, wherein the top of the structural
framework is comprised of two lateral beams intersecting the upper
one of said pair of parallel beams.
30. The combination of claim 29, wherein the two lateral beams are
located above the heat exchanger and provide the means by which the
heat exchanger and the structural framework can be lifted for
placement at a desired location.
Description
FIELD AND BACKGROUND OF THE INVENTION
[0001] The present invention relates, in general, to the field of
heat exchangers and, more particularly, to a heat exchanger having
an integral support structure and a structural framework for the
support thereof.
[0002] The present invention employs the teachings of U.S. Pat. No.
6,336,429 to Wiener et al., the text of which is hereby
incorporated by reference as though fully set forth herein.
[0003] To the extent that explanations of certain terminology or
principles of the heat exchanger, boiler and/or steam generator
arts may be necessary to understand the present invention, the
reader is referred to Steam/its generation and use, 40th Edition,
Stultz and Kitto, Eds., Copyright .COPYRGT.1992, The Babcock &
Wilcox Company, and to Steam/its generation and use, 41st Edition,
Kitto and Stultz, Eds., Copyright .COPYRGT.2005, The Babcock &
Wilcox Company, the texts of which are hereby incorporated by
reference as though fully set forth herein.
SUMMARY OF THE INVENTION
[0004] One aspect of the present invention is drawn to a heat
exchanger for transferring heat energy into a working fluid, such
as water. The heat exchanger is used to transform at least a
portion of the water from the liquid phase into saturated or
superheated steam.
[0005] Vertical steam/water separating devices, disclosed in the
aforementioned U.S. Pat. No. 6,336,429 to Wiener et al., are used
to separate the steam from the steam-water mixture. A pair of such
vertical steam/water separators, structurally interconnected and
arranged as described herein, provides an integral support
structure for the heat exchanger.
[0006] The heat exchanger of the present invention is
advantageously comprised of an arrangement of heat transfer
surfaces and fluid conveying conduits arranged in a particular
fashion to transfer a desired amount of heat energy into the water.
The heat transfer surfaces are advantageously made of tubes
arranged into panels, and are provided with inlet and outlet
headers as required. As is known to those skilled in the art, heat
transfer surfaces which convey steam-water mixtures are commonly
referred to as evaporative or boiler surfaces; heat transfer
surfaces which convey steam therethrough are commonly referred to
as superheating (or reheating, depending upon the associated steam
turbine configuration) surfaces. Regardless of the type of heating
surface, the sizes of tubes, their material, diameter, wall
thickness, number and arrangement are based upon temperature and
pressure for service, according to applicable boiler design codes,
such as the American Society of Mechanical Engineers (ASME) Boiler
and Pressure Vessel Code, Section I, or equivalent other codes as
required by law. Required heat transfer characteristics, pressure
drop, circulation ratios, spot absorption rates, mass flow rates of
the working fluid within the tubes, etc. are also important
parameters which must be considered. Depending upon the geographic
location where the heat exchanger is to be installed, applicable
seismic loads and design codes are also considered.
[0007] The heat exchanger is bottom supported from a base which is
part of an arrangement of interconnected rigid members that
surrounds the heat exchanger and forms a structural support
framework which, together with the aforementioned integral support
structure not only provides structural support and rigidity for the
heat exchanger, but also a means by which the heat exchanger can be
picked up and lifted for placement at a desired location. In the
case of an application of the heat exchanger as a solar heat energy
receiver, the structural support framework permits the entire
assembly of the heat exchanger and the framework to be assembled on
the ground and then lifted and set upon a tower during
installation. The structural support framework remains with the
heat exchanger, thereby facilitating (if necessary) the removal of
the heat exchanger from the tower should it become desirable to do
so.
[0008] In accordance with the present invention, there is provided
a heat exchanger comprising an arrangement of heat transfer
surfaces and a pair of vertical steam/water separators structurally
interconnected to one another and providing an integral support
structure for at least a portion of the heat transfer surfaces of
the heat exchanger. The structural interconnection includes upper
and lower structural members formed of heavy wall pipe and
extending between the vertical steam/water separators. Each of the
heavy wall pipes includes a pair of spaced inner partition walls
disposed in crosswise fashion to form a central portion therein
defining a header. The integrally supported portion of the heat
transfer surfaces extends between and is fluidically connected to
the headers of the upper and lower structural members.
[0009] Each of the vertical steam/water separators includes four
coplanar pedestal feet positioned at the lower end of the
steam/water separator, and arranged at equally spaced intervals
about the outer periphery of the steam/water separator.
[0010] The heat exchanger includes a structural support framework
in the shape of a rectangular parallelepiped having a top, a bottom
and opposing lengthwise sides surrounding the heat exchanger for
bottom support thereof.
[0011] The bottom of the structural support framework is comprised
of four horizontally extending parallel spaced lateral and
longitudinal beams intersecting one another to form a grid-like
structure which includes a lattice of obliquely-disposed web
members positioned between intersecting longitudinal and lateral
beams.
[0012] Two pairs of lateral braces intersect the inner two of the
four longitudinal beams of the bottom of the structural support
framework to form support bases for the vertical steam/water
separators. The pedestal feet of the steam/water separator are
fixedly secured to the respective support base.
[0013] Each of the opposing lengthwise sides of the structural
support framework has two pairs of parallel spaced vertical beams
located at opposite ends of the structural framework and one pair
of parallel spaced longitudinal beams intersecting the vertical
beams and located at the upper end of each of the opposing sides. A
lattice of obliquely-disposed web members is positioned between
each pair of vertical beams and the pair of longitudinal beams.
[0014] The top of the structural support framework is comprised of
two lateral beams intersecting the upper one of the pair of
parallel spaced beams extending along each lengthwise side. The two
lateral beams are located above the heat exchanger and provide a
means by which the heat exchanger and the structural support
framework can be lifted for placement at a desired location.
[0015] Another aspect of the present invention is drawn to the
combination of a heat exchanger and the structural framework used
for the support thereof. The combination comprises an arrangement
of heat transfer surfaces and a pair of vertical steam/water
separators structurally interconnected to one another and providing
an integral support structure for at least a portion of the heat
transfer surfaces. The structural interconnection between the heat
exchanger surfaces and the pair of vertical steam/water separators
is comprised of upper and lower heavy wall pipes, each pipe having
partitions therein defining a central header. The integrally
supported portion of the heat transfer surfaces extends between and
is fluidically connected to the headers of the upper and lower
heavy wall pipes. Each of the steam/water separators includes a
plurality of pedestal feet positioned at the lower end of the
steam/water separator.
[0016] The structural framework part of the combination has a top,
a bottom, and opposing lengthwise sides surrounding the heat
exchanger for bottom support thereof. The bottom of the structural
framework is comprised of four horizontally extending parallel
spaced lateral and longitudinal beams intersecting one another to
form a grid-like structure and includes a lattice of
obliquely-disposed web members positioned between intersecting
longitudinal and lateral beams. Two pairs of parallel spaced
lateral braces intersect the inner two of the four longitudinal
beams at the bottom of the structural framework to form support
bases for the vertical steam/water separators whose pedestal feet
are fixedly secured to their respective support bases. Each of the
opposing lengthwise sides of the structural framework has two pairs
of parallel spaced vertical beams located at opposite ends of the
structural framework and one pair of parallel spaced longitudinal
beams intersecting the vertical beams and located at the upper end
of each of the opposing sides. A lattice of obliquely-disposed web
members positioned between each pair of vertical beams and the pair
of longitudinal beams. The top of the structural framework is
comprised of two lateral beams intersecting the upper one of said
pair of parallel beams. The two lateral beams are located above the
heat exchanger and provide a means by which the heat exchanger and
the structural framework can be lifted for placement at a desired
location.
[0017] These and other features of the present invention will be
better understood and its advantages will be more readily
appreciated from the following description, especially when read
with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a perspective view of the heat exchanger which is
shown, for clarity, without the structural support framework of the
present invention;
[0019] FIG. 2 is an exploded perspective view of the heat exchanger
illustrated in FIG. 1;
[0020] FIG. 3 is a perspective view of the pair of vertical
steam/water separators structurally interconnected to one another
to provide an integral support structure in accordance with the
present invention; and
[0021] FIG. 4 is a perspective view of the integrally supported
heat exchanger structure of FIG. 3, together with the structural
framework used to support the heat exchanger structure in
accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Reference will hereinafter be made to the accompanying
drawings wherein like numerals designate the same or functionally
similar elements throughout the various drawings.
[0023] Referring to FIGS. 1-3, there is shown a heat exchanger 10
according to the present invention. The heat exchanger 10 has left
and right side walls 12, a roof portion 14, and a pair of vertical
steam/water separators 16 of the type disclosed in the
aforementioned U.S. Pat. No. 6,336,429 to Wiener et al. The
vertical steam/water separators 16 of this type are particularly
suited to handle large transient swings in heat input to the heat
exchanger 10 which may, in turn, cause large variations in water
levels within the steam/water separators 16. The side walls 12 are
comprised of panels of tubes having a welded membrane between
adjacent tubes. Welded membrane tube wall panels are well known to
those skilled in the art and will thus not be described in detail
here; for additional details, the reader is referred to the
aforementioned Steam texts. The roof portion 14 is also comprised
of welded membrane tube wall panels. While membrane wall tube
panels are typically employed in conventional industrial and
utility furnace walls to achieve a gas-tight construction, the
provision of the membrane between adjacent tubes in this
application also provides for structural rigidity of the panels and
it is for that purpose that the side wall panels 12 and roof
portion 14 have a membrane wall construction.
[0024] If the heat exchanger 10 is used to provide merely saturated
steam, the side walls 12 and roof portion 14 comprise evaporative
or boiler heating surface. If the heat exchanger 10 is used to
provide superheated steam, and as will be appreciated by those
skilled in the art, some of the heating surface will have to be
evaporative surface and other portions will have to be superheater
surface. In the embodiment shown in FIG. 1, the side walls 12 are
evaporative or boiler surface, and may be provided with inlet
headers 18 and outlet headers 20. The steam-water mixture generated
in tubes forming the side walls 12 is collected in the outlet
headers 20 which also serve as a mix point to even out temperature
imbalances which may exist in the steam-water mixture. Stubs 22 on
the outlet headers 20 are interconnected via risers (not shown) to
stubs 26 on upper portions of each of the vertical steam/water
separators 16. The vertical steam/water separators 16 operate in
known fashion (see U.S. Pat. No. 6,336,429 to Wiener et al.),
separating the steam from the steam-water mixture. If the heat
exchanger 10 is designed for saturated steam production, steam
outlet connections (not shown) from the top portions of each of the
separators 16 convey the steam to its downstream location and use.
If the heat exchanger 10 is designed to produce superheated steam,
the steam is conveyed from the separators 16 to superheater
surfaces for further heating and eventual collection and conveyance
to its downstream location and use. Depending upon the initial
steam temperature and pressure, and the desired outlet superheated
steam temperature desired, the superheater may have to be designed
as a multiple-pass superheater in order to provide adequate mass
flux rates within the superheater surface tubes, and such concepts
are within the scope of the present invention. Two-pass, four-pass
or additional pass designs may be required, taking into account the
temperatures of not only the tubes in the superheater, but also the
temperature of the tubes in an adjacent structure, in order to
address differential thermal expansion concerns. In either case,
the water separated from the steam-water mixture is conveyed to a
lower portion of each of the separators 16, mixed with make-up
feedwater, and conveyed to the evaporative surface to start the
process over again. In order to facilitate the circulation of the
water and water-steam mixture throughout the heat exchanger 10,
circulation pumps 28 may advantageously be provided at the lower
portion of each of the separators 16 for pumping the water back to
the evaporative surface via supplies (not shown).
[0025] Referring to FIG. 2, there is shown an exploded perspective
view of the heat exchanger illustrated in FIG. 1. This view better
illustrates the relationship between the side walls 12 and the
integral support structure, generally designated 30, comprised of
the pair of vertical steam/water separators 16 structurally
interconnected to one another by means of upper and lower
structural members 32.
[0026] Referring to FIG. 3, there is shown a perspective view of
the pair of vertical steam/water separators 16 structurally
interconnected to one another according to the present invention
which provides the integral support structure 30 for the heat
exchanger 10. The upper and lower structural members 32 are
advantageously comprised of heavy wall pipe, rather than a
structural I-beam or WF section, for reasons that will become
apparent. One end of each member 32 is connected to one of the
vertical steam/water separators, such as by welding. The structural
members 32 do not, in and of themselves, provide any direct fluidic
interconnection between the separators 16. The heavy wall pipe that
makes up each of the structural members 32 is fitted with inner
partition walls 34 forming a central portion that comprises a
header 36 which performs a fluid collecting/conveying function. In
addition to providing an integral support structure for the heat
exchanger 10, the headers 36 which are part of the upper and lower
structural members 32, are interconnected to one another by an
arrangement of heating surface 38 which extends between and is
fluidically connected to the upper and lower headers 36. Typically,
the heating surface 38 is up-flowing evaporative surface, comprised
of tubes. Tube stubs 40 provide connections for risers (not shown)
which convey the steam-water mixture to the tube stubs 26 on the
separators 16 as hereinbefore described.
[0027] It will be noted that the heating surface 38 extends in
between the headers 36 of the upper and lower structural members 32
while providing a gap or space 42 between distal edges of the
heating surface 38 and the outer wall of the steam/water separators
16. The side walls 12 extend into this space 42, with the distal
edges of the heating surface 38 extending adjacent to and in close
proximity with the inside portions of the side walls 12. However,
in order to accommodate differential thermal expansion the heating
surface 38 is not connected to the side walls 12 in any rigid
fashion. The side walls 12 would be bottom supported from a base,
in a fashion similar to that described below with respect to the
integral support structure 30. The sidewalls 12 may also be
provided with buckstays, not shown, which are well known to those
skilled in the art as providing rigidity and support for membrane
tube wall construction.
[0028] Referring to FIG. 4, there is shown a perspective view of a
portion of the heat exchanger 10 according to the present
invention, similar to that illustrated in FIG. 1, together with a
structural framework 50 which supports the heat exchanger 10. For
clarity, there is shown only the integral support structure 30
comprised of the pair of vertical steam/water separators 16
structurally interconnected to one another by means of upper and
lower structural members 32.
[0029] The three dimensional structural framework 50 is generally
in a shape of a rectangular parallelepiped and is defined by the
top 51, the bottom 52, and the lengthwise sides 55, and includes
three sets of flanged beams extending in the three mutually
orthogonal directions, eight longitudinal beams 58, six lateral
beams 56, and eight vertical beams 54.
[0030] The bottom 52 of the structural framework 50 is comprised of
four parallel spaced longitudinal beams 58 and four parallel spaced
lateral beams 56 which connectedly intersect one another to form a
grid-like structure. A lattice of obliquely-disposed web members 60
is positioned between the intersecting longitudinal and lateral
beams 58 and 56 to structurally reinforce the grid-like structure
forming the bottom 52 and to stiffen or add rigidity to the
structural framework 50.
[0031] The bottom 52 of the structural framework 50 includes a pair
of support bases 53, each being formed by respective pairs of
parallel spaced lateral braces 57 connectedly intersecting the
inner pair of longitudinal beams 58. Each of the steam/water
separators 16 includes four pedestal feet 59 located at or near the
bottom of the steam/water separator. The pedestal feet 59 extend
outwardly from the steam/water separator wall at a substantially
right angle, and are coplanar and arranged at equally spaced
intervals about the outer periphery of the steam/water separator
16. The pedestal feet 59 are each provided with a reinforcing
gusset 61 and are fixedly secured to the support base 53.
[0032] Each of the lengthwise sides 55 of the structural framework
50 is comprised of two pairs of parallel spaced vertical beams 54
located at opposite ends of the structural framework 50, and one
pair of parallel spaced longitudinal beams 58 located at the upper
end of the sides 55 and connectedly intersecting the vertical beams
54. A lattice of obliquely-disposed web members 60 is positioned
between each pair of vertical beams 54 and the longitudinal beams
58 to structurally reinforce the sides 55 and to stiffen the
structural framework 50.
[0033] The top 51 of the structural framework 50 is comprised of
two lateral beams 56 which intersect and are connected to the upper
one of each of the pairs of longitudinal beams 58 located at the
upper end of the lengthwise sides 55. In addition to reinforcing
the top 51 and stiffening the structural framework 50, the top
lateral beams 56 are generally located over the heat exchanger 10
and provide a means by which the heat exchanger 10 and the
supporting structural framework 50 can be picked up and lifted for
placement at a desired location.
[0034] Although the present invention has been described above with
reference to particular means, materials, and embodiments, it is to
be understood that this invention may be varied in many ways
without departing from the spirit and scope thereof, and therefore
is not limited to these disclosed particulars but extends instead
to all equivalents within the scope of the following claims.
* * * * *