Ex Parte Howard

Patent Trial and Appeal Board

Feb 15, 2017

12207757 (P.T.A.B. Feb. 15, 2017)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
12/207,757 09/10/2008 HENRY EDWARD HOWARD 08-3019 1302
27182 7590 02/15/2017
PRAXAIR, INC.
LAW DEPARTMENT
10 RIVERVIEW DRIVE
DANBURY, CT 06810-5113
EXAMINER
RUSSELL, DEVON L
ART UNIT PAPER NUMBER
3744
MAIL DATE DELIVERY MODE
02/15/2017 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________________

Ex parte HENRY EDWARD HOWARD
____________________

Appeal 2014-003490
Application 12/207,757
Technology Center 3700
____________________

Before MICHELLE R. OSINSKI, JILL D. HILL, and
PAUL J. KORNICZKY, Administrative Patent Judges.

OSINSKI, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Henry Edward Howard (Appellant)1 appeals under 35 U.S.C. § 134
from the Examiner’s decision rejecting claims 1–8, which are all of the
pending claims. We have jurisdiction under 35 U.S.C. § 6(b).

We AFFIRM-IN-PART.

1 Appellant identifies the real party in interest as Praxair Technology, Inc.
Br. 2.
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THE CLAIMED SUBJECT MATTER
Claim 1, the sole independent claim, is reproduced below and is
representative of the claimed subject matter on appeal.
1. A method of supplying refrigeration to air separation plants
located within an air separation plant facility, such method
comprising:
producing a refrigerant at a cryogenic temperature within
a refrigeration system; and
introducing streams of the refrigerant, while at the
cryogenic temperature into the air separation plants such that all
or a part of the refrigeration requirements of the air separation
plants are supplied by the streams of the refrigerant.

EVIDENCE
The Examiner relied on the following evidence in rejecting the claims
on appeal:
REJECTIONS
I. Claims 1–4 and 6–8 stand rejected under 35 U.S.C. § 103(a) as
unpatentable over Dee and Tranier. Final Act. 2 (incorporating by
reference the Non-Final Office Action mailed Aug. 31, 2012
(hereinafter referred to as “Non-Final Act.”)); Non-Final Act. (Aug.
31, 2012) 2–4.
II. Claim 5 stands rejected under 35 U.S.C. § 103(a) as unpatentable over
Dee, Tranier, and Voit. Final Act. 2 (incorporating by reference Non-
Final Act.); Non-Final Act. 4–5.
Voit
Tranier
Dee
US 5,802,874
US 7,143,606 B2
US 2008/0000266 A1
Sept. 8, 1998
Dec. 5, 2006
Jan. 3, 2008
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OPINION
Rejection I
Claims 1, 2, 4, and 6
The Examiner relies on Dee for disclosing a method of supplying
refrigeration to an air separation plant, the method comprising “producing a
refrigerant at cryogenic temperature (liquid nitrogen 186) within a
refrigeration system (2); and introducing a stream of the refrigerant . . . into
the air separation plant.” Non-Final Act. 2 (citing Dee, Fig. 1b); Ans. 2–3
(citing Dee, Fig. 1b). The Examiner acknowledges that Dee fails to disclose
“multiple air separation plants located in an air separation plant facility.”
Non-Final Act. 3; Ans. 3. The Examiner finds that “Tranier discloses the
use of multiple air separation units in a single system which share common
nitrogen sub-system piping.” Non-Final Act. 3; Ans. 3 (citing Tranier, Fig.
5).
The Examiner concludes that “[i]t would have been obvious to one of
ordinary skill in the art at the time of the invention to provide multiple air
separation units, as taught by Tranier, in order to increase production
capacity.” Non-Final Act. 3; Ans. 3. As to why Tranier would lead one of
ordinary skill in the art to use streams from the same, single refrigeration
system 2 to supply the multiple air separation units, the Examiner takes the
position that Tranier teaches “to centrally consolidate functionalities that are
common to all separation trains.” Ans. 6. More specifically, the Examiner
states that:
Trainer proposes that as a matter of optimization in plant design
it is desirable to combine heat exchange functions into a central
location when possible rather than splitting up an external
stream. This optimization through centralization provides the
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motivation to simply increase the size of the existing liquid
nitrogen generator and route the liquid nitrogen to each of the air
separation units, rather than also doubling the number of liquid
nitrogen production units.
Ans. 6–7.
Appellant argues that Dee contemplates “us[ing] the existing plant to
supply more nitrogen to the [LNG] liquefier” in order “to allow the liquefier
to produce more liquid nitrogen,” not “using the increased liquefaction
capability of the liquefier to supply appreciably more refrigeration to the
existing plant.” Br. 7. Appellant adds that “there is no suggestion in Dee
that the liquefier 2 . . . would ever be used to supply refrigerant to two or
more separate air production units 1 to increase production.” Id. at 9.
Appellant’s argument is not persuasive because it fails to address the
rejection as articulated by the Examiner which is not based on Dee alone,
but on the combination of Dee and Tranier.
As to Tranier, Appellant argues that rather than teaching supplying
refrigeration from a single source (such as an LNG liquefier) to multiple air
separation plants, Tranier teaches “a method of supplying refrigeration from
[multiple] air separation plants to a [single] natural gas liquefier.” Br. 9
(emphasis added); see also id. at 10, 11 (restating the argument). In
particular, Appellant argues that although “Tranier has common piping that
connects all of the air separation plants to the natural gas liquefier, it does
not have common piping that connects a liquefier or some similar device
that would generate refrigerant streams to air separation plants to supply all
or part of the refrigeration requirements to such air separation plants.” Id. at
10. Although we agree with Appellant on this point, we are not persuaded
of error in the Examiner’s rejection because of it. The rejection as
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articulated by the Examiner in the Answer is not based on simply inserting
Tranier’s system into that of Dee, but rather on optimizing Dee’s system
(after it has been modified to include multiple air separation units as taught
by Tranier) based on the broader centralization principles of Tranier so as to
centralize the heat exchange function in Dee’s existing liquid nitrogen
generator, rather than including multiple liquid nitrogen production units.
Ans. 6–7. Appellant does not persuasively address why the Examiner’s
reasoning based on the broader centralization principle of Tranier lacks
rational underpinnings.
Appellant further argues that because “no additional refrigeration is
required by the plants shown in Tranier, there would be no suggestion to
centrally supply the same from a refrigeration system.” Br. 12. Appellant
asserts that the multiple air separation units of Tranier “each ha[ve] its own
refrigeration system (turboexpander 13) that is necessary for the plants to
operate and supply streams of refrigerant to liquefy the natural gas.” Id. at
11–12. Again, we do not disagree with Appellant on this point, but are not
persuaded of error in the Examiner’s rejection because of it. The
Examiner’s rejection is based on modifying and optimizing Dee based on the
teachings of Tranier (Ans. 6–7), not on modifying Tranier. Appellant does
not persuasively explain why the Examiner’s reasoning to modify Dee so as
to include multiple air separation units and so as to centralize heat exchange
via Dee’s existing liquid nitrogen generator, rather than increasing the
number of liquid nitrogen production units, lacks rational underpinnings.
Appellant additionally argues that Dee “specifically calls for the
liquefier to be designed to accept additional compression equipment to allow
the plant output to be increased,” rather than “indicati[ng] that two or more
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plants could be connected to the liquefier shown in Dee.” Br. 12. Again, we
are not persuaded that the Examiner’s articulated reasoning lacks rational
underpinnings. Merely because Dee suggests increasing plant output
another way (via supplemental processing unit 3) does not demonstrate that
the Examiner’s articulated reasoning to provide multiple air separation units
to increase production capacity or plant output (Ans. 3) lacks rational
underpinnings.
For the foregoing reasons, we are not persuaded that the Examiner
erred in concluding that Dee and Tranier renders obvious the subject matter
of claim 1, and we sustain the rejection of independent claim 1 as
unpatentable under 35 U.S.C. § 103(a) over these references. We also
sustain the rejection of claims 2, 4, and 6, which depend therefrom, and for
which Appellant relies on the same arguments and reasoning we found
unpersuasive in connection with the independent claim. Br. 12.
Claim 3
Claim 3 depends from claim 1 and recites that “the refrigeration
system is operated on an intermittent basis such that liquid production of the
air separation plants is increased during operation of the refrigeration
system.” Br. 19 (Claims App.). The Examiner finds that Dee’s system
meets this claim limitation because the “claim is broad enough to mean that
the air separation system is switched on at the same time that the liquid
production system is turned on or, alternatively, that the systems merely
function concurrently.” Ans. 3 (citing Dee, ¶ 33).
Appellant argues that “Dee does not . . . contemplate that liquefier 2
could be used on an intermittent basis or in other words[,] an[] ‘on’ and ‘off’
basis because liquefier 2 is the sole source of refrigeration that is supplied to
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air separation unit 1 . . . . If liquefier 2 w[]ere turned off, . . . the air
separation unit 1 would rapidly heat up, liquid within the columns would
dump[,] and it would take hours to restart the plant.” Br. 13. In contrast,
Appellant explains that the Specification contemplates the air separation
plant can supply its own refrigeration using compressors 26, 29 and
expander 32, with this refrigeration being “sufficient to maintain the plant in
thermal balance.” Id. As to the Examiner’s interpretation of the claim,
Appellant asserts that it is in error because “[w]hile any product production
would be non-existent in Dee if the liquefier 2 w[]ere turned off, this is not
the case in the present invention and such a reading of claim 3 would be at
odds with the plain meaning of the terminology used in the claim, the
written description and knowledge in the art.” Id.
During examination, claim terms are given their broadest reasonable
interpretation consistent with the Specification. In re Acad. of Sci. Tech.
Ctr., 367 F.3d 1359, 1369 (Fed. Cir. 2004). Appellant has not persuasively
explained why the Examiner’s broad interpretation of “intermittent”
operation of the refrigeration system is unreasonable. The Examiner’s
interpretation, although broad, explains that the refrigeration system (Dee’s
liquefier) and air separation plant can be turned on and off concurrently,
thereby providing for intermittent operation of both the refrigeration system
and the air separation plant. The Examiner’s interpretation also explains
how liquid production of the air separation plant will be increased during the
concurrent operation with the refrigeration system, relative to liquid
production during the concurrent shutdown of the refrigeration system and
air separation plant. Because the Examiner is contemplating concurrent
shutdown of the refrigeration system (liquefier 2) and air separation unit 1
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(Ans. 3), Appellant’s argument about air separation unit 1 rapidly heating up
when operating without liquefier 2 does not adequately address the rejection
as articulated by the Examiner (Br. 13).
To the extent Appellant is arguing that “intermittent” operation of the
refrigeration system contemplates that there be at least some refrigeration for
the air separation plant even during “off” periods of the intermittent
operation of the refrigeration system to provide at least some product
production (Br. 13), the language of claim 3 is broader and we decline to
import specific characteristics associated with “intermittent” operation of the
refrigeration system in the Specification as a limitation of claim 3. See
Superguide Corp. v. DirecTV Enterps., Inc., 358 F.3d 870, 875 (Fed. Cir.
2004) (“Though understanding the claim language may be aided by the
explanations contained in the written description, it is important not to
import into a claim limitations that are not a part of the claim. For example,
a particular embodiment appearing in the written description may not be
read into a claim where the claim language is broader than the
embodiment.”).
For the foregoing reasons, we are not persuaded that the Examiner
erred in concluding that Dee and Tranier renders obvious the subject matter
of claim 3, and we sustain the rejection of claim 3 as unpatentable under 35
U.S.C. § 103(a) over these references.
Claim 7
Claim 7 depends indirectly from independent claim 1 and recites that:
an oxygen-rich liquid stream is pumped to produce a
pumped liquid oxygen stream;
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at least part of the pumped liquid oxygen stream is
vaporized or pseudo vaporized within the main heat exchanger
through indirect heat exchange with a compressed air stream; and
the compressed air stream after the indirect heat exchange
is introduced into a liquid expander and introduced into at least
one of the higher pressure column and the lower pressure
column, thereby to impart part of the refrigeration requirements
of the at least first of the air separation plants.
Br. 20 (Claims App.).
The Examiner finds that Dee teaches liquid oxygen line 158 and
compressed air stream 230 cooled through indirect heat exchange in main
heat exchanger 110. Ans. 4. The Examiner also finds that Dee teaches
compressed air stream 230 is introduced into liquid expander 236, 240 and
two columns 114, 116. Id. The Examiner acknowledges that Dee fails to
disclose that liquid oxygen line 158 is pumped and vaporized in main heat
exchanger 110. Id. The Examiner finds that Tranier teaches liquid oxygen
stream 21 is pumped 23 through main heat exchanger 7 and concludes that it
would have been obvious to one of ordinary skill in the art to provide Dee’s
system “with the use of pumped liquid oxygen for increased cooling power
in the main heat exchanger, as taught by Tranier.” Id.
Appellant argues that “even if [Dee and Tranier] were combined, they
would not meet the terms of Applicants[’] invention as called for in claim 7
in that Tranier does not have a liquid expander that would impart
refrigeration requirements to a plant.” Br. 14. Appellant also argues that
“[t]here is no excess refrigeration generated in Dee that is either available
for export or that would be required to balance warm end losses if the air
stream were sufficiently compressed to heat a pumped liquid oxygen
stream” because “liquefier 2 is [only] used to liquefy nitrogen produced by
the plant and also to add refrigeration to the plant.” Id. at 15. These
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arguments are unpersuasive in that they each address the references
individually, rather than the combination of Dee and Tranier.
Appellant also argues that the Examiner’s stated reasoning lacks
rational underpinnings in that “no[] increased cooling power is imparted by
virtue of the pumped liquid oxygen” to the main heat exchanger because
“the energy balance is a ‘wash.’” Br. 15. Appellant asserts that “[t]he
energy of the compressed air is transferred to the warming pressurized
oxygen and warm end heat exchange refrigeration losses are compensated
for with the turbine 13.” Id.
The Examiner responds that “it is clear that the use of the cooling
power of the otherwise removed liquid oxygen stream (158) within the heat
exchanger (110) would clearly increase the cooling capacity of the heat
exchanger by using an already available source of cooling. Ans. 8. The
Examiner further responds that “even a ‘wash’ is an improvement over the
system of Dee which does not use the cooling power of the liquid oxygen
available and therefore has an energy ‘loss’ with regard to the liquid oxygen
stream.” Id. at 8–9. We agree with the Examiner’s response, and we are not
persuaded that the Examiner’s articulated reasoning lacks rational
underpinnings.
For the foregoing reasons, we are not persuaded that the Examiner
erred in concluding that Dee and Tranier renders obvious the subject matter
of claim 7, and we sustain the rejection of claim 7 as unpatentable under 35
U.S.C. § 103(a) over these references.
Claim 8
Claim 8 depends indirectly from independent claim 1 and recites that:
the compressed air stream is a first compressed air stream;
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a second compressed air stream is partly cooled within the
main heat exchanger and expanded to produce an exhaust stream;
the exhaust stream is introduced into the higher pressure
column to impart a further part of the refrigeration requirement
of the at least first of the air separation plants; and
the at least one of the nitrogen-rich liquid streams is
introduced into the at least first of the air separation plants to
increase liquid production within at least first of the air
separation plants.

Br. 21 (Claims App.).
The Examiner finds that Dee teaches first air compressed stream 230
and second compressed air stream 208. Ans. 4. The Examiner
acknowledges that Dee fails to teach that second compressed air stream 208
is only partly cooled, expanded, and introduced into the high pressure
column. Id. The Examiner finds that Tranier teaches first compressed air
stream 11 is cooled before being expanded and introduced into a column and
second compressed air stream 9 is partially cooled in the heat exchanger,
expanded 13, and introduced into high pressure column 15. Id.
Appellant asserts that “the use of a turboexpander to impart
refrigeration in Dee would not be obvious in the first instance in that
refrigeration is imparted through LNG which would be available at a
terminal in abundance for such purposes.” Br. 16. Appellant also asserts
that “not only is there no need for an expander to produce refrigeration, there
is also no need for any liquid nitrogen introduction to the high pressure
column.” Id. The Examiner responds that Appellant “fails to address the
inherent benefits of the combination in increased efficiency” by
“economizing the otherwise withdrawn liquid oxygen stream.” Ans. 9.
Although the Examiner’s response reiterates the reasoning for pumping
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liquid oxygen line 158 for vaporization in main heat exchanger 110, we are
not persuaded that the Examiner has articulated adequate reasoning having a
rational underpinning to explain specifically why one of ordinary skill in the
art would have been led to partly cool and expand second compressed air
stream 208 before introduction into the high pressure column.
For the foregoing reasons, we are persuaded that the Examiner erred
in concluding that Dee and Tranier render obvious the subject matter of
claim 8, and we do not sustain the rejection of claim 8 as unpatentable under
35 U.S.C. § 103(a) over these references.
Rejection II
Claim 5 depends indirectly from independent claim 1 and recites that
“the nitrogen-rich vapor stream is liquefied in the refrigeration system by
compressing and cooling a portion of the nitrogen-rich vapor contained
within the nitrogen-rich vapor stream and refrigeration for the cooling is
generated at least in part by expanding another portion of the nitrogen-rich
vapor within a turbo expander.” Br. 20 (Claims App.). The Examiner finds
that Voit teaches
that it is old and well-known in the art to liquefy a gaseous
nitrogen stream originating from the top of a low pressure
column (504, 1) which has been fully warmed in a main heat
exchanger (502) in an air separation unit (500) by: compressing
(4, 6, 8, 10) and cooling (12a) a portion of the gaseous nitrogen
(19) and providing refrigeration in part by expanding (102)
another portion (101, 103) of the nitrogen vapor in a turbo
expander.
Final Act. 2 (incorporating by reference Non-Final Act.); Non-Final Act. 5.
The Examiner concludes that it would have been obvious to one of ordinary
skill in the art to provide Dee’s method, as modified by Tranier, with a
nitrogen liquefaction process as taught by Voit “in order to allow the
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construction of air separation facilities independently of LNG facilities.”
Non-Final Act. 5; Ans. 5.
Appellant acknowledges that “nitrogen liquefiers exist that use
compression and expansion cycles as shown in Voit,” but assert that it would
not be obvious to modify Dee to do so. Br. 17–18. Appellant explains that
“if the liquefier of Voit were used to replace the LNG liquefier 2 of Dee[,]
there would be . . . no reason to add a unit 3 thereto when a greater nitrogen
production were desired” as taught by Dee. Id. at 18.
The Examiner responds that Appellant’s argument does not
persuasively explain “why simply changing the mechanism that provides
liquefaction power from LNG (as taught by Dee) to a well-known
compression-expansion cycle (as taught by Voit) would decrease the
demand for liquid nitrogen in the system.” Ans. 9–10. The Examiner
“maintains that the usefulness of top of the column nitrogen gas as a feed to
the modified liquefying structure to generate a larger amount of liquid
nitrogen would remain unaltered.” Id. at 10. We agree with the Examiner’s
response. Absent a persuasive explanation of why changing the liquefaction
power mechanism from LNG to a compression-expansion cycle would
decrease the demand for liquid nitrogen in the system, we are not persuaded
that the Examiner’s articulated reasoning lacks rational underpinnings.
For the foregoing reasons, we are not persuaded that the Examiner
erred in concluding that Dee, Tranier, and Voit renders obvious the subject
matter of claim 5, and we sustain the rejection of claim 5 as unpatentable
under 35 U.S.C. § 103(a) over these references.
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DECISION
The Examiner’s decision to reject claims 1–4, 6, and 7 under
35 U.S.C. § 103(a) as unpatentable over Dee and Tranier is affirmed.
The Examiner’s decision to reject claim 8 under 35 U.S.C. § 103(a) as
unpatentable over Dee and Tranier is reversed.
The Examiner’s decision to reject claim 5 under 35 U.S.C. § 103(a) as
unpatentable over Dee, Tranier, and Voit is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED-IN-PART