Ex Parte Porter

Board of Patent Appeals and Interferences

Nov 24, 2009

09954063 (B.P.A.I. Nov. 24, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte Rodney Porter
____________________

Appeal 2009-004661
Application 09/954,063
Technology Center 3700
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Decided: November 24, 2009
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Before RICHARD E. SCHAFER, SALLY GARDNER LANE, and
MICHAEL P. TIERNEY, Administrative Patent Judges.

TIERNEY, Administrative Patent Judge.

DECISION ON APPEAL

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A. STATEMENT OF THE CASE
This is a decision on appeal by the real party in interest, Rodney
Porter (Porter) under 35 U.S.C. § 134(a) from a final rejection of claims
1-33, the only claims on appeal. Porter requests reversal of the Examiner’s
rejections of claims 1-33. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.

References Relied on by the Examiner
Tenner 4,021,186 May 3, 1977
Okigami et al. (Okigami) 4,395,223 July 26, 1983
Benedek et al. (Benedek) 5,645,413 July 8, 1997

The Invention
Porter is directed to a method and apparatus for reducing the Nitrogen
Oxide (NOX) emissions of a natural gas furnace. (Spec. Abstract, 1:4-6)
Porter’s method and apparatus utilize primary and secondary combustion
zones. (Id. at Abstract, 6:4 to 7:9) Porter teaches that NOX emissions are
reduced in the primary combustion zone by limiting the amount of
combustion air, such that only partial combustion of the natural gas takes
place. (Id. at Abstract, 6:9-11, 8:2-8) After the gas is partially combusted in
the primary combustion zone, it subsequently enters an upper secondary
combustion zone. (Id. at 8:11-18) Porter teaches that additional air is
introduced into the secondary combustion zone along with the partially
combusted natural gas. (Id.) The additional introduced air allows for the
partially combusted gas to ignite and burn at a lower temperature and
thereby further reduce NOX emissions. (Id. at 8:14 to 9:8)
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There are five independent claims on appeal, claims 1, 9, 15, 23, and
29. (App. Br. 23-32, Claims App’x.) Claims 1, 15, and 23 are directed to an
apparatus or system for reducing NOX emissions in a furnace. Claims 9 and
29 are directed to a method for reducing NOX emissions in a furnace.
Claim 23 is illustrative of the claimed invention and is reproduced below.
23. An improved combustion system for reducing NOX in a furnace
including:
a primary flame zone for burning fuel which produces
flue gas without NOX;
a secondary flame zone above the primary flame zone;
means in the primary flame zone for facilitating the
passage of uncombusted natural gas into the secondary flame
zone; and
means in the secondary flame zone for injecting a
predetermined amount of air into the secondary flame zone at a
predetermined level above the primary flame zone and at a
lower adiabatic flame temperature than that of the primary
flame zone temperature so that uncombusted natural gas in the
secondary flame zone is combusted thereby reducing NOX
emissions from the furnace.

(App. Br. 29-30, Claims App’x.)

The Rejections on Appeal
The Examiner provided the following grounds of rejection for the
claims on appeal:
1. The Examiner rejected claims 23 and 29 under 35 U.S.C.
§ 102(b) as anticipated by Tenner.
2. The Examiner rejected claims 1-22, 24-28, and 30-33 under
35 U.S.C. § 103(a) as unpatentable over Tenner, Benedek, and
Okigami.
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Claims 23 and 29, which were rejected under 35 U.S.C. § 102(b) as
anticipated by Tenner, stand or fall together.
Claims 1-22, 24-28, and 30-33 stand rejected together under
35 U.S.C. § 103(a). Claims 3-4, 10-11, 17-18, 20, 25-26, and 31 are not
separately argued. With regard to claims 2, 5-9, 12-16, 19, 21-22, 24,
27-28, 30, and 32-33, Porter does no more than identify the elements of the
claims and state that the claim elements are not taught or suggested by the
applied references. We hold that Porter has not separately argued claims 2,
5-9, 12-16, 19, 21-22, 24, 27-28, and 30-33. See, 37 C.F.R. § 41.37
(c)(l)(vii)) Accordingly, we hold that claims 2-22, 24-28, and 30-33 stand or
fall with our determination as to the patentability of claim 1.
B. ISSUE
1. Has Porter shown that the Examiner incorrectly found that Tenner
teaches introducing a predetermined amount of air into a secondary flame
zone at a predetermined level above a primary flame zone, and combusting
gas at a lower adiabatic flame temperature than that of the primary flame
zone?
2. Has Porter shown that the Examiner incorrectly determined that the
prior art provides a reason for one of ordinary skill in the art to introduce a
predetermined amount of air into a secondary flame zone at a predetermined
level above a primary flame zone, and combust gas at a lower adiabatic
flame temperature than that of the primary flame zone?

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C. FINDINGS OF FACT
Tenner
1. Tenner teaches a method and apparatus for reducing NOX emissions
in furnaces. (Tenner 1:27-36)
2. Tenner’s method and apparatus use a primary combustion chamber
and a secondary combustion chamber that is located above the primary
combustion chamber. (Id. at 3:9-14, 3:59 to 4:23, Fig. 1)
3. Tenner teaches that the primary combustion chamber reduces NOX
emissions by lowering the air to fuel ratio. (Id. at 2:64 to 3:2, 3:46-51)
4. Tenner however teaches that the lowered air-to-fuel ratio allows for
only partial combustion of the fuel to take place within the primary
combustion chamber. (Id.)
5. Tenner allows the partially combusted fuel to rise and enter the
secondary combustion chamber, where combustion of the fuel is completed.
(Id. at 3:9-14, 3:59 to 4:23, Fig. 1)
6. To complete the combustion process, Tenner teaches that a
predetermined amount of additional air is introduced into the secondary
combustion chamber at the outlet of the primary chamber. (Id. at 3:9-14,
4:3-23, Claim 5)
7. Tenner teaches that cooling the combustion products leaving the
primary combustion chamber results in “a further reduction of NOX.” (Id. at
4:40-43)

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D. PRINCIPLES OF LAW
A claim is anticipated if each and every element as set forth in the
claim is found in a single prior art reference. Verdegaal Bros. Inc. v. Union
Oil Co., 814 F.2d 628, 631 (Fed. Cir. 1987).
An invention is not patentable under 35 U.S.C. § 103 if it is obvious.
KSR Int’l Co. v. Teleflex Inc. (KSR), 550 U.S. 398, 406 (2007). Any need or
problem known in the field of endeavor at the time of invention can provide
a reason for combining elements in the manner claimed. Id. at 420. In
particular, the “combination of familiar elements according to known
methods is likely to be obvious when it does no more than yield predictable
results.” Id. at 416.

E. ANALYSIS
The Examiner rejected claims 23 and 29 under 35 U.S.C. § 102(b) as
anticipated by Tenner. The Examiner rejected claims 1-22, 24-28, and
30-33 under 35 U.S.C. § 103(a) as obvious over Tenner in combination with
Benedek and Okigami.

Claims 23 and 29

The Examiner found that Tenner anticipated all the limitations of
claims 23 and 29. The Examiner and Porter disagree, however, as to
whether Tenner taught: (I) inducing a predetermined amount of air into the
secondary flame zone at a predetermined level above the primary flame
zone, and (II) combusting gas at a lower adiabatic flame temperature than
that of the primary flame zone. Additionally, Porter contends that Tenner
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fails to teach that cooling occurs between the primary and secondary stages.
(App. Br. 9-12)
Tenner is directed to a method and apparatus for reducing NOX
emissions in furnaces. (Tenner 1:27-36) To reduce NOX emissions Tenner
uses a primary combustion chamber and a secondary combustion chamber
that is located above the primary combustion chamber. (Id. at 3:9-14, 3:59
to 4:23, Fig. 1) Specifically, Tenner teaches initially reducing NOX
emissions by lowering the air to fuel ratio in the primary combustion
chamber. (Id. at 2:64 to 3:2, 3:46-51) Tenner teaches that lowering the air-
to-fuel ratio in the primary combustion chamber allows for only partial
combustion of the fuel to take place. (Id.) Tenner’s partially combusted
fuel is allowed to rise and enter a secondary combustion chamber, where
combustion of the fuel is completed. (Id. at 3:9-14, 3:59 to 4:23, Fig. 1)
To complete the combustion process, Tenner teaches that a
predetermined amount of additional air is introduced into the secondary
combustion chamber at the outlet of the primary combustion chamber.
(Id. at 3:9-14, 4:3-23, Claim 5) Accordingly, we find that Tenner teaches
Porter’s claimed injection of a predetermined amount of air into the
secondary flame zone at a predetermined level above the primary flame
zone.
Tenner introduces air into the secondary combustion chamber where it
is mixed with the heated air rising from the primary combustion zone. Thus,
the additional air would be cooler than the combustion products from the
primary chamber and serve to lower the temperature of the partially
combusted fuel. Moreover, Tenner teaches one of ordinary skill in the art
that “a further reduction of NOX would be obtained by cooling the
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combustion products from the primary combustion chamber.” (Id.
at 4:40-43) Since Tenner does not preheat the air entering the secondary
chamber, and Tenner also recognizes benefits from cooling the combustion
products leaving the primary combustion chamber, one of ordinary skill in
the art would recognize Tenner as teaching combusting the gas in the
secondary chamber at a lower adiabatic flame temperature than that of the
primary flame zone.
Based on the foregoing, Porter has not shown that the Examiner
incorrectly found that Tenner teaches (I) introducing a predetermined
amount of air into the secondary flame zone at a predetermined level above
the primary flame zone, or (II) combusting gas at a lower adiabatic flame
temperature than that of the primary flame zone.

Claims 1-22, 24-28 and 30-33
The Examiner determined that the combination of Tenner, Benedek,
and Okigami taught all claim limitations of the remaining claims (1-22,
24-28, and 30-33). (Ans. 5-7) The Examiner relied on Benedek and
Okigami to teach additional claimed features that were not clearly taught by
Tenner alone and set forth explicit reasons for combining Tenner, Benedek,
and Okigami. (Id.)
Porter contends that there is no reason to combine Tenner, Benedek,
and Okigami. Porter does not however dispute the Examiner’s reliance on
Benedek and Okigami to teach the additional features, nor does Porter
dispute the explicit reasons to combine provided by the Examiner. (compare
Ans. 6-7 and App. Br. 10-12) Instead, Porter’s contention that there is no
reason to combine the references merely reiterates Porter’s above contention
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that Tenner fails to teach either: (I) inducing a predetermined amount of air
into the secondary flame zone at a predetermined level above the primary
flame zone, or (II) combusting gas at a lower adiabatic flame temperature
than that of the primary flame zone. (App. Br. 12).
As discussed above, we hold that Tenner teaches the disputed
limitations. Accordingly, we hold that Porter has failed to show that the
Examiner incorrectly determined that the combination of Tenner, Benedek,
and Okigami provides a reason for one of ordinary skill in the art to
construct the claimed furnace having reduced NOx emissions.

F. CONCLUSION
1. Porter has not shown that the Examiner incorrectly found that Tenner
teaches introducing a predetermined amount of air into a secondary flame
zone at a predetermined level above a primary flame zone, and combusting
gas at a lower adiabatic flame temperature than that of the primary flame
zone.
2. Porter has not shown that the Examiner incorrectly determined that
the prior art provides a reason for one of ordinary skill in the art to introduce
a predetermined amount of air into a secondary flame zone at a
predetermined level above a primary flame zone, and combust gas at a lower
adiabatic flame temperature than that of the primary flame zone.
G. ORDER
The rejections of claims 23 and 29 under 35 U.S.C. § 102(b) as
anticipated by Tenner are affirmed.
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The rejections of claims 1-22, 24-28, and 30-33 under 35 U.S.C.
§ 103(a) as unpatentable over Tenner, Benedek, and Okigami are 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

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Kenneth D. Baugh
2413 Blodgett
Houston, TX 77004