Bechtel Hydrocarbon Technology Solutions, Inc.

Patent Trials and Appeals Board

Nov 3, 2020

2020001298 (P.T.A.B. Nov. 3, 2020)

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.
14/808,620 07/24/2015 Guang-Chung Lee 8643-305 9581
30903 7590 11/03/2020
CRAIN, CATON & JAMES
FIVE HOUSTON CENTER
1401 MCKINNEY, 17TH FLOOR
HOUSTON, TX 77010
EXAMINER
RAYMOND, KEITH MICHAEL
ART UNIT PAPER NUMBER
3793
NOTIFICATION DATE DELIVERY MODE
11/03/2020 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
ipdocket@craincaton.com
jhudson@craincaton.com
wjensen@craincaton.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte GUANG-CHUNG LEE and SUDHIR GOLIKERI
__________

Appeal 2020-01298
Application 14/808,620
Technology Center 3700
__________

Before PHILLIP J. KAUFFMAN, ANNETTE R. REIMERS, and
TARA L. HUTCHINGS, Administrative Patent Judges.

REIMERS, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 8–19. Claims 1–7 and 20 have been
canceled. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42. Appellant identifies the real party in interest as Bechtel
Hydrocarbon Solutions, Inc. Appeal Brief (“Appeal Br.”) 3, filed Aug. 16,
2019.
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CLAIMED SUBJECT MATTER
The claimed subject matter relates to natural gas liquefaction. Spec.
¶ 6. According to Appellant, the compact nature of a supplemental cooling
system including a heat exchanger enclosing a portion of a process feed gas
line, a portion of a chilled liquid line, a portion of a refrigeration intercooler
line, and a portion of a refrigeration aftercooler line contributes to reducing
the power requirement for producing liquefied natural gas (LNG). Appeal
Br. 8–9 (citing Spec. ¶ 23).
Claims 8, 15, and 17 are independent. Claim 8 is illustrative of the
claimed subject matter and recites:
8. A method for chilling a process feed gas using a
supplemental cooling system, which comprises:
circulating a chilled liquid through a chilled liquid line
passing through a heat exchanger, wherein each end of the
chilled liquid line is in fluid communication with the
supplemental cooling system;
sending a refrigeration intercooler and a refrigeration
aftercooler through a refrigeration intercooler line and a
refrigeration aftercooler line, respectively, passing through the
heat exchanger; and
chilling the process feed gas as the process feed gas passes
through a portion of a process feed gas line in the heat exchanger
next to the refrigeration intercooler in the refrigeration
intercooler line, the refrigeration aftercooler in the refrigeration
aftercooler line and the chilled liquid in the chilled liquid line.

THE REJECTION
Claims 17–19 stand rejected under 35 U.S.C. § 103 as unpatentable
over Bridgwood (US 2010/0212329 A1, published Aug. 26, 2010),
Gushanas (US 2011/0226008 A1, published Sept. 22, 2011), and Stein
(US 3,680,327, issued Aug. 1, 1972).
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Claims 8, 9, and 12–14 stand rejected under 35 U.S.C. § 103 as
unpatentable over Bridgwood and Gushanas.
Claims 15 and 16 stand rejected under 35 U.S.C. § 103 as
unpatentable over Bridgwood, Low (US 6,158,240, issued Dec. 12, 2000),
and Gushanas.
Claims 10 and 11 stand rejected under 35 U.S.C. § 103 as
unpatentable over Bridgwood, Gushanas, and Briesch (US 2011/0088399
A1, published Apr. 21, 2011).

ANALYSIS
Obviousness over Bridgwood and Gushanas
Claims 8, 9, and 12–14
Appellant does not offer arguments in favor of dependent claims 9
and 12–14 separate from those presented for independent claim 8. Appeal
Br. 8–10. We select claim 8 as the representative claim, and claims 9 and
12–14 stand or fall with claim 8. 37 C.F.R. § 41.37(c)(1)(iv) (2018).
Independent claim 8 is directed to a method performed using a heat
exchanger through which a chilled liquid line, a refrigeration intercooler
line, and a refrigerator aftercooler line pass. Appeal Br. 12 (Claims App.).
The method includes the step of “chilling the process feed gas as the process
feed gas passes through a portion of a process feed gas line in the heat
exchanger next to the refrigeration intercooler in the refrigeration intercooler
line, the refrigeration aftercooler in the refrigeration aftercooler line and the
chilled liquid in the chilled liquid line.” Id.
Appellant contends that the arrangement of “a process feed gas line in
the heat exchanger next to the refrigeration intercooler in the refrigeration
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intercooler line, [and] the refrigeration aftercooler in the refrigeration
aftercooler line” was found patentable over Bridgwood and other prior art
during the prosecution of the related parent application because “none of the
prior art provides that an aftercooler line, an intercooler line, a process gas to
be cooled, and a chilled liquid connected with an ejector are all positioned in
a heat exchanger.” See Appeal Br. 8–9 (citing page 5 of the Notice of
Allowance for U.S Patent Application No. 14/763,290 mailed July 12,
2016).
In response, the Examiner correctly notes that “[e]ach [patent]
application is examined on its own merits” and “the current rejection utilizes
a new reference (Gushanas) found in the examination of the current [patent]
application.” Ans. 3 (emphasis omitted).2
Appellant contends that Gushanas’ “pre-cooling systems indicated at
202, 204 and 206 are not lines–much less a refrigeration intercooler line and
a refrigeration after cooler line.” Appeal Br. 9; see also Reply Br. 4–5.3
As an initial matter, we note that both Bridgwood and Gushanas
describe natural gas liquefaction methods or systems. Bridgwood ¶ 29;
Gushanas ¶ 25. In particular, Bridgwood describes a natural gas liquefaction
method in which process feed gas 60 is cooled by transferring heat to chilled
water in chiller 66. Bridgwood ¶ 31. In addition, Bridgwood teaches
cooling pre-treated feed gas 60 in a chiller upstream of refrigeration zone 28
so as to reduce the cooling load required for liquefaction. Id. ¶¶ 34–37.

2 Examiner’s Answer (“Ans.”), dated Oct. 1, 2019.
3 Reply Brief (“Reply Br.”), filed Dec. 2, 2019.
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Similarly, Gushanas describes a natural gas liquefaction system that
makes use of a single mixed refrigerant. Gushanas ¶¶ 25, 27. The system,
as depicted in Figure 7 of Gushanas, includes interstage drum 22 and
accumulator drum 54. Id. ¶¶ 20, 43. A first stage compressor compresses a
gaseous component of the refrigerant upstream of interstage drum 22. See
id. ¶ 28 (describing first stage compressor 11 of the system of Figure 3,
which performs analogously to the first stage compressor depicted in Figure
7). Pre-cooling system 204, interposed between the first stage compressor
and interstage drum 22, “is for interstage pre-cooling of mixed phase stream
18 as it travels . . . to interstage drum 22.” Gushanas ¶ 43, Fig. 7.4 Warm,
relatively heavy fraction components of the refrigerant in interstage drum 24
form an intermediate pressure liquid stream that flows to liquefaction heat
exchanger 6. See id. ¶ 29 (describing interstage drum 22 of the system of
Figure 3, which performs analogously to interstage drum 22 of Figure 7).
A second stage compressor upstream of accumulator drum 54
compresses an intermediate pressure vapor stream comprising vapor and
liquid phases from interstage drum 44. See Gushanas ¶ 30 (describing
second stage compressor 44 of the system of Figure 3, which performs
analogously to the second stage compressor depicted in Figure 7). Pre-
cooling system 206, interposed between the second stage compressor (not
labeled in Figure 7) and accumulator drum 54, “is for discharge pre-cooling
of mixed phase stream 52 as it travels to accumulator drum 54.” Id. ¶ 43,
Fig, 7. High pressure liquid and vapor streams exiting accumulator drum 54

4 We note that Figure 7 of Gushanas mistakenly labels two elements as item
204. We refer to the element that includes a diagonal zigzag arrow.
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flow to liquefaction heat exchanger 6. See id. ¶ 30 (describing drum 54 of
the system of Figure 3, which performs analogously to accumulator drum 54
depicted in Figure 7).
Based on these findings of Gushanas, we agree with the Examiner that
fluid passing through pre-cooling system 204 corresponds to the
“intercooler” recited in claim 8 because system 204 cools the fluid
constituting intermediate pressure liquid and vapor streams. Final Act. 7;
see also Ans. 4.5 We also agree with the Examiner that the fluid passing
through pre-cooling system 206 corresponds to the “aftercooler” recited in
claim 8 because system 206 cools the fluid constituting the high pressure
liquid and vapor streams. Final Act. 7; see also Ans. 4.
Appellant contends that Gushanas does not teach or suggest that “a
refrigeration intercooler line could be combined with [an] after-cooler [line]
and [a] process feed gas line in heat exchanger 6.” Appeal Br. 9–10; see
also Reply Br. 4–5. In other words, according to Appellant, Gushanas does
not disclose “chilling the process feed gas in the heat exchanger next to the
refrigeration intercooler line and the refrigeration aftercooler line” as
required by claim 8. Appeal Br. 9–10; see also Reply Br. 4–5. However, as
correctly pointed out by the Examiner, Gushanas expressly teaches that pre-
cooling systems 204, 206 “could be incorporated into a single multi-stream
heat exchanger.” Gushanas ¶ 44; see also Ans. 4. As such, we agree with
the Examiner that this teaching would have suggested replacing separate
pre-cooling systems 204, 206 with intercooler and aftercooler lines passing

5 Final Office Action (“Final Act.”), dated Jan. 18, 2019.
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next to each other, and next also to a chilled liquid line, in a single heat
exchanger. Ans. 4.
Appellant contends that a skilled artisan would not have had reason
“to apply the Gushanas pre-cooling system to the Bridgwood feed chiller.”
Reply Br. 5 (emphasis omitted); see also Appeal Br. 10. In particular,
Appellant contends that as Bridgwood “teaches primary cooling of the feed
gas in a first heat exchanger (chiller 66), pretreating the chilled feed gas and
then secondary cooling of the pretreated feed gas in a second heat exchanger
(refrigeration zone 28),” Bridgwood “teaches away from enclosing a portion
of the process feed gas line, a portion of the refrigeration intercooler line and
a portion of the refrigeration aftercooler line in the first heat exchanger
(chiller 66)” because such a modification would be perceived by a skilled
artisan “as redundant and unnecessarily increasing the power requirement
for producing LNG in view of the second heat exchanger (refrigeration zone
28) used.” Appeal Br. 10 (citing Bridgwood ¶¶ 37, 44, 45); see also Reply
Br. 5–6 (arguing that “[s]imply substituting the Gushanas refrigeration
system for the Bridgwood feed chiller 66, as proposed by the reasoning in
the Answer (pp. 5–6), would be redundant and pointless.”).
As an initial matter, Appellant does not direct us to any discussion in
Bridgwood and/or Gushanas or provide sufficient evidence to support the
contention that the proposed modification would be perceived by a skilled
artisan “as redundant and unnecessarily increasing the power requirement
for producing LNG in view of the second heat exchanger (refrigeration zone
28) used.” Appeal Br. 10. In re Pearson, 494 F.2d 1399, 1405 (CCPA
1974) (“Attorney’s argument in a brief cannot take the place of evidence.”).
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As discussed above, Bridgwood describes pre-cooling the process
feed gas by heat transfer to chilled water in chiller 66. Bridgwood ¶ 31.
Bridgwood separately teaches pre-cooling the process feed gas in a chiller
upstream of refrigeration zone 28. Bridgwood ¶¶ 34–36. Gushanas teaches
combining the intercooler and aftercooler lines with a chilled liquid line in
the same heat exchanger. Gushanas ¶ 44. As such, we agree with the
Examiner that a skilled artisan would have had reason to combine either
Bridgwood’s chiller 66, or another chiller for pre-cooling the process feed
gas, with the single heat exchanger used to pre-cool the intercooler and
aftercooler. Ans. 5. By doing so, a skilled artisan would have “utilize[d] all
heat exchanged streams in a common heat exchanger . . . to save on plot
space and quantity of equipment and insulation needed and required.” Final
Act. 7; see also Ans. 5. Additionally, we agree with the Examiner that
modifying the system of Bridgwood by “combining of heat exchangers to
provide cooling to multiple streams at once as disclosed by Gushanas”
would not teach away from Bridgwood as Gushanas provides that it was
well known in the art at the time of Appellant’s invention to provide
intercoolers and aftercoolers either in the same heat exchanger as the feed
chiller or in a heat exchanger separate from the feed chiller. Ans. 5
(emphasis omitted); see also Gushanas ¶ 44.
We also agree with the Examiner that “providing the refrigeration
system of Gushanas to the feed chiller of Bridgwood is a simple substitution
of one known element for another to obtain predictable results.” Ans. 5–6
(emphasis omitted). As discussed above, both Bridgwood and Gushanas
describe natural gas liquefaction methods or systems. Bridgwood ¶ 29;
Gushanas ¶ 25; see also Ans. 6 (“[B]oth Gushanas and Bridgwood provide
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refrigeration systems for pre-cooling and cooling a feed.” (emphasis
omitted)). Thus, a skilled artisan would have had reason “to apply the heat
exchanger and intercooling/aftercooling incorporated system of Gurshanas
with the chiller of Bridgwood as it is simply applying a known technique to
improve similar devices in the same way.” Ans. 6 (emphasis omitted). In
other words, “the refrigeration technique of Gurshanas[,] which incorporates
an intercooler and aftercooler precooling systems into the same heat
exchanger as the chiller of natural gas[,] can [] be utilized to improve the []
feed chiller of natural gas of Bridgwood” by “allow[ing] for a more efficient
heat exchange operation” as well as “tak[ing] advantage of a smaller plot
space.” Ans. 6 (emphasis omitted). Appellant does not provide persuasive
evidence or argument apprising us of error in the Examiner’s findings. See
Appeal Br. 10; see also Reply Br. 5–6.
In summary, and based on the record presented, we are not persuaded
the Examiner erred in rejecting independent claim 8 as unpatentable over
Bridgwood and Gushanas. Accordingly, we sustain the Examiner’s rejection
of claim 8. We further sustain the rejection of claims 9 and 12–14, which
fall with claim 8.

Obviousness over Bridgwood, Low, and Gushanas
Claims 15 and 16
Appellant acknowledges the rejection of claims 15 and 16, but fails to
provide an argument for their patentability separate from the arguments
presented in support of the patentability of claim 8. Appeal Br. 8. As we
find no deficiencies in the Examiner’s rejection of claim 8 as unpatentable
over Bridgwood and Gushanas, for the reasons discussed above, we likewise
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sustain the rejection of claims 15 and 16 as unpatentable over Bridgwood,
Low, and Gushanas.

Obviousness over Bridgwood, Gushanas, and Stein
Claims 17–19
Appellant contends that, “[b]ecause claim 17 includes the same
limitations that distinguish [claim 8] from the prior art, claim 17 is likewise
distinguished from the same prior art.” Appeal Br. 11. As we find no
deficiencies in the Examiner’s rejection of claim 8 as unpatentable over
Bridgwood and Gushanas, for the reasons discussed above, we likewise
sustain the rejection of claims 17–19 as unpatentable over Bridgwood,
Gushanas, and Stein.

Obviousness over Bridgwood, Gushanas, and Briesch
Claims 10 and 11
Appellant acknowledges the rejection of claims 10 and 11, but fails to
provide an argument for their patentability separate from the arguments
presented in support of the patentability of claim 8. Appeal Br. 8. As we
find no deficiencies in the Examiner’s rejection of claim 8 as unpatentable
over Bridgwood and Gushanas, for the reasons discussed above, we likewise
sustain the Examiner’s rejection of claims 10 and 11 as unpatentable over
Bridgwood, Gushanas, and Briesch.

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CONCLUSION
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
17–19 103 Bridgwood,
Gushanas, Stein
17–19
8, 9, 12–14 103 Bridgwood,
Gushanas
8, 9, 12–14
15, 16 103 Bridgwood, Low,
Gushanas
15, 16
10, 11 103 Bridgwood,
Gushanas, Briesch
10, 11
Overall
Outcome
8–19

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).

AFFIRMED