U.S. patent application number 15/878709 was filed with the patent office on 2018-07-26 for structual support assembly for cold box structures in an air separation unit.
The applicant listed for this patent is Nick J. Degenstein, Karl K. Kibler, Kevin J. Saboda. Invention is credited to Nick J. Degenstein, Karl K. Kibler, Kevin J. Saboda.
Application Number | 20180209727 15/878709 |
Document ID | / |
Family ID | 61148539 |
Filed Date | 2018-07-26 |
United States Patent
Application |
20180209727 |
Kind Code |
A1 |
Saboda; Kevin J. ; et
al. |
July 26, 2018 |
STRUCTUAL SUPPORT ASSEMBLY FOR COLD BOX STRUCTURES IN AN AIR
SEPARATION UNIT
Abstract
A pre-fabricated or shop-built structural support assembly cold
box structures containing distillation columns or other cold box
equipment in an air separation unit is provided.
Inventors: |
Saboda; Kevin J.; (Long
Beach, CA) ; Kibler; Karl K.; (Amherst, NY) ;
Degenstein; Nick J.; (The Woodlands, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Saboda; Kevin J.
Kibler; Karl K.
Degenstein; Nick J. |
Long Beach
Amherst
The Woodlands |
CA
NY
TX |
US
US
US |
|
|
Family ID: |
61148539 |
Appl. No.: |
15/878709 |
Filed: |
January 24, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62450181 |
Jan 25, 2017 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E04H 5/10 20130101; F25J
3/04945 20130101; F25J 3/04872 20130101; F25J 2290/42 20130101;
F25J 3/04878 20130101; F25J 3/04672 20130101; F25J 3/0489
20130101 |
International
Class: |
F25J 3/04 20060101
F25J003/04 |
Claims
1. A pre-fabricated structural support assembly for an air
separation unit, the pre-fabricated structural support comprising:
a structural frame; a plurality of platforms connected to the
structural frame; at least one ladder or stairway connected to the
structural frame or one or more of the plurality of platforms; and
a plurality of piping or ducts connected to the structural frame or
to the one or more of the plurality of platforms, the plurality of
piping or ducts configured to be fluidically interconnected to one
or more cold box structures of the air separation unit; wherein the
platforms are configured to support one or more persons and the at
least one ladder or stairway is configured to connect the plurality
of platforms and allow one or more persons to move between
platforms; wherein the pre-fabricated structural support assembly
is configured to be transported to a location of the air separation
unit and further configured to be affixed and fluidically
interconnected to one or more cold box structures of the air
separation unit.
2. The pre-fabricated structural support assembly of claim 1,
wherein the structural support assembly is configured to be
anchored to a concrete foundation at the location of the air
separation unit.
3. The pre-fabricated structural support assembly of claim 1,
wherein the structural frame further comprises one or more braces
configured to provide partial support of the one or more cold box
structures against seismic forces and wind forces acting on the one
or more cold box structures.
4. The pre-fabricated structural support assembly of claim 1,
wherein at least one of the plurality of platforms further comprise
at least one extendable platform that is configured to be retracted
during transportation to keep an in-transit height and/or an
in-transit width below a prescribed dimension, and the at least one
extendable platform further configured to be extended when affixed
to the one or more cold box structures of the air separation
unit.
5. The pre-fabricated structural support assembly of claim 1,
further comprising: one or more insulated enclosures disposed on at
least one of the plurality of platforms.
6. The pre-fabricated structural support assembly of claim 5,
wherein the one or more insulated enclosures are configured to
house cold-end equipment selected from the group consisting of heat
exchangers, subcoolers, condensers, expansion joints, storage
vessels, cryogenic valves, cryogenic pumps, and cryogenic piping or
combinations thereof.
7. The pre-fabricated structural support assembly of claim 1,
wherein some or all of the plurality of piping or ducts are
insulated with aerogel insulation.
8. The pre-fabricated structural support assembly of claim 1,
wherein at least one of the plurality of piping or ducts is
configured to be fluidically interconnected with at least two cold
box structures of the air separation unit.
9. The pre-fabricated structural support assembly of claim 1,
wherein at least one of the plurality of piping or ducts is
configured to be fluidically interconnected between at least two
locations on a single cold box structure of the air separation
unit.
10. The pre-fabricated structural support assembly of claim 1,
wherein the pre-fabricated structural support assembly is
configured to fit on a trailer and transported via truck to the
location of the air separation unit.
11. The pre-fabricated structural support assembly of claim 1,
wherein the pre-fabricated structural support assembly is
configured to fit on a rail car and transported via train to the
location of the air separation unit.
12. The pre-fabricated structural support assembly of claim 1,
further comprising one or more structural bases and configured to
provide a base for the one or more cold box structures of the air
separation unit wherein the one or more cold box structures of the
air separation unit are disposed on the one or more structural
bases such that the one or more cold box structures of the air
separation unit are elevated off the ground.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority from U.S.
Provisional Patent Application Ser. No. 62/450,181 filed on Jan.
25, 2017, the disclosure of which is incorporated by reference
herein.
TECHNICAL FIELD
[0002] The present invention relates to a pre-fabricated structural
support assembly for cold box structures containing distillation
columns or other cold box equipment for an air separation unit.
BACKGROUND
[0003] The use of pre-fabricated packages that are readily
transportable to a facility site for the construction of a
cryogenic air separation unit has been previously described in
United States Patent Application Publication Nos. 2015/0096327 and
2007/0199344 as well as U.S. Pat. No. 5,461,871. Such pre-packaged
units or modular units described in the prior art all are directed
to operational or functional equipment (e.g. `cold-end` equipment
or `warm-end` equipment) required for the cryogenic separation of
air.
[0004] For example, in United States patent application publication
No. 2015/0096327, the transportable package is a cold-box package
unit that does not include the high pressure column or low pressure
column of the air separation unit, the main heat exchanger or
auxiliary columns such as the argon column, but rather includes a
separate cold box that houses other cold-end equipment and
accessories for the air separation unit such as condensers,
piping/conduits and terminals for connecting the conduits to the
high pressure column, low pressure column, auxiliary columns and to
the main heat exchanger.
[0005] Likewise, in United States patent application publication
No. 2007/0199344, the modular unit or package is a cold box package
unit that specifically includes the rectification columns of the
air separation unit and ancillary cold-end equipment such as the
main heat exchanger.
[0006] The modular units described in U.S. Pat. No. 5,461,871 also
include operational or functional equipment required for the
separation of air. However, the described modular units include
both warm-end modules for warm-end equipment such as air
compression equipment, and air purification equipment as well as
cold box modules containing cold-end equipment such as heat
exchangers, subcoolers, cryogenic valves, cryogenic pumps,
turbines, and rectification columns.
[0007] In the aforementioned prior art references, the
pre-fabricated or shop built cold box packages for the `cold-end`
equipment are operatively coupled together via site work and field
piping connections. The required site work further requires
installing the cold box package, attaching the ladders, stairs,
etc. to the modular or pre-packaged cold box and other finishing
work. What is needed is a means to further reduce the field
construction time of an air separation unit, and particularly,
reduce field construction time of a cold box arrangement for an air
separation unit by also providing a shop constructed or
pre-fabricated structural support assembly which functions as a
cold-box integration module.
SUMMARY OF THE INVENTION
[0008] The present invention may be characterized as a
pre-fabricated structural support assembly for an air separation
unit, the pre-fabricated structural support comprising: (i) a
structural frame; (ii) a plurality of platforms connected to the
structural frame; (iii) at least one ladder or stairway connected
to the structural frame or one or more of the plurality of
platforms; and (iv) a plurality of piping or ducts connected to the
structural frame or to the one or more of the plurality of
platforms, the plurality of piping or ducts configured to be
fluidically interconnected to one or more cold box structures of
the air separation unit. The pre-fabricated structural support
assembly is configured to be transported to a location of the air
separation unit and further configured to be affixed and
fluidically interconnected to one or more cold box structures of
the air separation unit. The platforms are configured to support
one or more persons and the at least one ladder or stairway is
configured to connect the plurality of platforms and allow one or
more persons to move between platforms and access to selected
locations on the cold box structures. The plurality of piping or
ducts are arranged or configured to fluidically interconnect the
cold box structures of the air separation unit.
[0009] The pre-fabricated structural support assembly also may
include a plurality of braces configured to provide partial
structural support of the cold box structures against seismic
forces and wind forces acting on the cold box structures. The
plurality of platforms may also include one or more extendable
platform that are configured to be retracted during transportation
to keep an in-transit height and/or an in-transit width below a
prescribed dimension, and further configured to be extended when
affixed to the cold box structures of the air separation unit.
[0010] The pre-fabricated structural support assembly also may
include one or more insulated enclosures that are configured to
house cold-end equipment that is fluidically interconnected to at
least one of the cold box structures of the air separation unit.
Some or all of the plurality of piping or ducts as well as the
insulated enclosure may be insulated with aerogel insulation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] While the specification concludes with claims specifically
pointing out the subject matter that Applicant regards as the
invention, it is believed that the invention will be better
understood when taken in connection with the accompanying drawings
in which;
[0012] FIG. 1 is an illustration of a pre-fabricated structural
support assembly disposed between two cold box structures in an air
separation unit in accordance with an embodiment of the present
invention; and
[0013] FIG. 2 is a schematic illustration of a pre-fabricated
structural support assembly supporting or connected to a plurality
of cold box structures in an air separation unit in accordance with
an alternate embodiment of the present invention.
DETAILED DESCRIPTION
[0014] As well known in the art, oxygen, nitrogen and argon
products are often produced from a compressed and purified feed air
stream through a cryogenic rectification process in an air
separation unit. Typically, such gaseous and/or liquid products are
produced in an air separation unit for on-site customers or
pipeline customers, with any excess products often converted to
merchant liquid products for nearby customers. An air separation
unit commonly employs a Linde-type double column cryogenic air
separation arrangement that includes a lower pressure distillation
column, a higher pressure distillation column coupled together in a
heat exchange relationship to recover oxygen and nitrogen, and
optional third and/or fourth distillation columns (e.g. low ratio
column and/or superstage column) to recover argon. In addition to
the distillation columns, the air separation unit also includes
pre-purification systems, compression equipment, a primary heat
exchanger, one or more condensers, one or more auxiliary heat
exchangers, a turbine based refrigeration system, as well as a
plurality of pumps, valves, storage tanks, conduits/piping,
etc.
[0015] As portions of the air separation process are conducted at
cryogenic temperatures, air separation units will typically have
one or more cylindrical or rectangular shaped cold boxes to house
the distillation columns, heat exchangers, and other `cold-end`
equipment. Such cold box structures are typically designed and
constructed to withstand the expected wind and/or seismic loads and
in accordance with local building code requirements. Such cold box
structures for air separation units may be shop built or, in many
cases, field erected. In some cases, a hybrid construction approach
may be employed where portions of the cold box structure are shop
fabricated in a plurality of modules and then the modules are
assembled together in the field to erect the final cold box
structure.
[0016] Cold box structures for air separation units also typically
have multiple access panels distributed along the height of the
coldbox structure. To access these access panels, and thus the
distillation column or other equipment disposed within the cold box
structure, the cold box structures must have a series of stairs or
ladders to allow personnel to climb up to the various access
panels. Some air separation units use stairs that circumnavigate
the cold box structures in a spiral pattern while other air
separation units use ladders that are directly attached to the
outer surface of the cold box structures.
[0017] Distillation columns for an air separation unit are also
either shop built or field assembled. With shop fabrication, the
distillation column for the air separation unit (including column
internals) is fully assembled, piped, and often pre-installed into
a shop fabricated cold box structure. This final assembled cold box
structure (including the distillation column) is then shipped to
the field site and erected on a foundation. With field assembly of
a distillation column, an empty or bare column shell is shipped to
the field site in one or more pieces and then installed into a cold
box structure. The required column internals and associated piping
are typically installed after the distillation column is positioned
in the cold box structure. Shop fabricated and assembled columns
are generally preferred to field constructed columns, since shop
fabrication and assembly is generally less expensive than field
construction and assembly.
[0018] A hybrid alternative of distillation column construction is
to install most of the required piping and column internals on-site
but at ground level before the distillation column is raised and
installed into the cold box structure. The advantage of installing
piping and column internals at ground level in a field construction
project is that it avoids elevated assembly and welding work in
tight spaces. A disadvantage associated with installing the piping
and column internals at ground level of the field site is the
possibility of damaging the piping upon installation into the cold
box structure and the crane weight loading requirements are
increased.
[0019] As discussed in more detail below, the present invention is
a pre-fabricated or shop-built structural support assembly
configured to be disposed adjacent to or even between the cold box
structures of an air separation unit. The structural support
assembly is further configured to provide access to the cold box
structures and the equipment contained therein and provides partial
structural support for adjacent cold box structures as well as
interconnecting piping between the cold box structures.
[0020] Turning now to FIG. 1, there is shown an illustration of a
pre-fabricated structural support assembly supporting two cold box
structures in an air separation unit. The pre-fabricated structural
support assembly 10 for cold box structures 30 of an air separation
unit, includes a structural frame 12 as well as a plurality of
platforms 14 and railings 15 connected to the structural frame 12
to allow personnel to access selected locations on the cold box
structures 30 during construction and operation of the air
separation unit. The pre-fabricated structural support assembly 10
further includes a plurality of stairways and/or ladders 16 (see
also FIG. 2) connecting the plurality of platforms 14 such that
personnel can climb up and down the structural support assembly 10
to access selected locations on the cold box structures 30 during
construction and operation of the air separation unit. The
pre-fabricated structural support assembly 10 preferably also
includes pre-fabricated piping, ducts and/or conduits 20 to move
the gas and fluid streams between selected locations on the cold
box structures 30 and an insulated enclosure 25. As shown, the
illustrated structural support assembly is preferably anchored in
the ground or to a concrete foundation. A plurality of structural
braces 18 connecting portions of the structural frame 12 are also
shown.
[0021] The pre-fabricated structural support assembly 10 functions
as a stand-alone cold-box integration module during both
construction and operation that structurally and operatively
couples the cold boxes of the air separation unit. As a
pre-fabricated or shop built structure, the structural support
assembly 10 is also configured to be transported to the site of the
air separation unit via truck or other commercial carrier and is
further configured to be easily lifted and then lowered into place
between the cold box structures and then rigidly affixed to the
separate cold box structures 30 of the air separation unit.
[0022] In FIG. 2, there is shown a schematic illustration of
another embodiment of the pre-fabricated structural support
assembly. As seen therein, the pre-fabricated structural support
assembly 10 is connected to and/or supports multiple cold box
structures 30 of an air separation unit, including the lower
pressure distillation column, a higher pressure distillation
column, a primary heat exchanger 36, and an argon or low ratio
column. This embodiment of the pre-fabricated structural support
assembly 10 also includes a structural frame 12; a plurality of
fixed platforms 14 with railings 15 connected to the structural
frame 12; a plurality of stairways and/or ladders 16 connecting the
plurality of platforms 14; a plurality of extendable platforms 17;
a plurality of structural braces 18 connecting portions of the
structural frame 12; one or more insulated enclosures 25; and a
series of pre-fabricated piping, ducts and/or conduits 20 (not
shown in FIG. 2 but see FIG. 1) arranged or configured to move gas
and/or fluid streams between selected locations on the multiple
cold box structures 30.
[0023] As with the previously described embodiment, the plurality
of stairways and/or ladders 16 connecting the plurality of
platforms 14 are arranged or configured such that personnel can
climb up and down the structural support assembly 10 to the various
platforms 14 (and extendable platforms 17) to access selected
locations on the cold box structures 30 during construction and
operation of the air separation unit.
[0024] The plurality of fixed platforms 14 together with the
extendable platforms 17 (which are connected to the fixed
platforms) allow personnel to access selected locations on the cold
box structures 30 during construction and operation of the air
separation unit. During transport of the pre-fabricated structural
support assembly 10 to the installation site, the extendable
platforms 17 are in a retracted position adjacent to the fixed
platforms 14 and retained within the boundaries of the structural
frame 12. Once the structural support assembly 10 is lowered into
place at the installation site adjacent to two of the cold box
structures, the extendable platforms 17 are slid outwardly from the
structural frame extending towards the cold box structures in an
extended position and bolted to the cold box structures. In
situations where the structural support assembly 10 provides
partial structural support to the cold box structures 30, the
structural support assembly 10 preferably includes structural
braces extending between portions of the structural frame 12 and/or
the cold box structures 30.
[0025] In the illustrated embodiment of FIG. 2, the structural
support assembly 10 is shown positioned on top of and anchored to a
raised structure of the air separation unit, which could be another
cold box structure. In addition, the structural support assembly 10
includes an elevated support base 19 proximate the top of the
structural support assembly 10. The elevated support base 19 is
configured to support one of the cold box structures 30 so as
elevate a distillation column within the cold box structure to take
advantage of gravity feed of one or more streams from the
distillation column and eliminate the use of a pump (e.g. liquid
reflux pump).
[0026] The external dimensions of the pre-fabricated structural
support assembly usually determine the in-transit dimensions of the
package. One such dimension is the height (h) of the structural
support assembly 10 which is understood to represent the dimension
in the vertical direction from the ground based on the orientation
and positioning of the structural support assembly 10 when finally
assembled as part of the air separation unit. The other salient
dimensions are the width (w) and depth (d) of the structural
support assembly 10 which are understood to represent the
dimensions of the structural support assembly 10 as measured on a
line or plane perpendicular to the vertical direction. In transit,
the height of the structural support assembly determines the
in-transit length while the width of the structural support
assembly and depth of the structural support assembly defines the
in-transit height and in-transit width.
[0027] The structural support assembly 10 is preferably
pre-fabricated in a shop or factory which is generally remote from
the installation site of the air separation unit. Such shop based
pre-fabrication allows some minimization of the construction
requirements and activities at the installation site, where
environmental conditions are often much more difficult. Since the
pre-fabricated structural support assembly 10 is typically
transported from the shop or factory to the installation site via
commercial vehicles such as a tractor trailer truck, there are
various Department of Transportation (DOT) regulations and local
restrictions as to the in-transit length, in-transit width, and
in-transit height of the transported item.
[0028] In situations where the structural support assembly 10
includes pre-fabricated ducts, conduits, or other piping, such
pre-fabricated piping 20 only needs to be welded on the ends to the
associated piping of the cold box structures 30. Since a majority
of this welding of the interconnecting piping could be done from
the platforms 14 (or extended platforms 17) on the structural
support assembly 10 it would eliminate much of the elevated site
work and scaffolding requirements currently used during
construction of an air separation unit. In addition, where the
structural support assembly 10 includes pre-fabricated piping,
ducts or conduits, such items may be pneumatically pressure tested
in the shop during fabrication thereby eliminating or minimizing
the pneumatic test requirements that need to be performed
on-site.
[0029] The structural frame 12 is preferably constructed from steel
frame members and is arranged to define a generally open interior
space. The pre-fabricated ducts, conduits, or other piping 20 of
the structural support assembly 10 are generally arranged in the
open interior space and terminate near edges of the structural
frame 12 at locations that align with the locations of the
corresponding piping in the cold box structures 30.
[0030] The structural frame 12 also preferably defines the
dimensions of the structural support assembly 10 and allows the
structural support assembly 10 to be efficiently packaged, shipped
and lifted into place without damaging the piping 20 disposed in
the open interior spaces. Using a pre-fabricated structural support
assembly 10 that provides partial structural support of the cold
box structures 30, it may be possible to reduce the height to base
ratio of the cold box structures 30, which lowers the construction
cost of the cold box structures 30 while still meeting the wind
load requirements and other requirements of the local building
codes. The lower construction costs are realized as a result of the
significant reductions in the amount of structural steel in each
cold box structures, making them less expensive, lighter, and
easier to install.
[0031] One or more insulated enclosures 25 can be optionally
designed into the pre-fabricated structural support assembly 10.
The insulated enclosures 25 are preferably disposed on a platform
14 and sized to accommodate cold-end equipment that is too large or
too heavy to install with the field interconnecting piping.
Cold-end equipment such as superheaters, subcoolers, argon
refineries, condensers, and liquid storage tanks can be located
within the insulated enclosures 25 of the structural support
assembly 10 along with the any required interconnecting piping
which could free up space in the cold box packages for larger
distillation columns or larger primary heat exchanger cores.
[0032] While the present invention has been described with
reference to one or more preferred embodiments and operating
methods associated therewith, it should be understood that numerous
additions, changes and omissions to the disclosed system and method
can be made without departing from the spirit and scope of the
present invention as set forth in the appended claims.
* * * * *