Ex parte Carter

Board of Patent Appeals and Interferences

Sep 21, 2000

08266809 (B.P.A.I. Sep. 21, 2000)

The opinion in support of the decision being entered today was not written for
publication and is not binding precedent of the Board.
Paper No. 16
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte H. RANDY CARTER
____________
Appeal No. 1997-2674
Application No. 08/266,809
____________
ON BRIEF
____________
Before JOHN D. SMITH, OWENS, and DELMENDO, Administrative Patent
Judges.
DELMENDO, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on an appeal under 35 U.S.C. § 134
from the examiner’s final rejection of claims 6, 7, 9, and 10,
which are all of the claims pending in this application.
Claim 9 is illustrative of the claims on appeal and is
reproduced below:
9. A method for injecting NO inhibiting liquidx
reagent into a boiler having boiler gas flowing
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therein in a direction of flow, the boiler including
an opening, the method comprising:
mounting a conduit having a nozzle, the conduit
being activable for injecting NO inhibiting reagent,x
and mounting the conduit such that the conduit and
nozzle are movable into the gas in the boiler
through the opening and movable out of the gas and
out of the opening;
sensing a temperature of the gas in the boiler;
when the temperature of the gas is sensed to be
within a selected range, activating the conduit to
insert the nozzle into the gas through the opening
and activating the conduit to spray reagent through
the nozzle into the gas; and
when the temperature of the gas is sensed to be
outside the selected range, activating the conduit
to withdraw the nozzle from the gas and out of the
opening, and deactivating the conduit so that no
reagent is supplied through the conduit to the
nozzle.
The subject matter on appeal generally relates to a
method for injecting NO inhibiting liquid reagent into thex
flue gas of a utility or industrial type boiler in order to
reduce the emission of NO (specification, page 3, lines 2-5). x
The appellant states that the main goal of the invention is to
enable NO liquid reagent to be used in an appropriatex
temperature window at the most efficient location within the
flue gas passageways in order to maximize pollution control
Appeal No. 1997-2674
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efficiency (id.). According to the appellant, the invention
achieves this objective by employing a conduit and spray
nozzle that is normally retracted from the harsh environment
of the boiler and inserted into the flue gas passageways only
when a temperature sensor, operatively located at the conduit
entrance to the flue gas passageway, senses the optimum
temperature for reagent injection (id.).
As evidence of obviousness, the examiner relies upon the
following prior art reference:
Burton 4,842,834 June 27, 1989
Claims 6, 7, 9, and 10 stand rejected under 35 U.S.C. §
103 as unpatentable over Burton (examiner’s answer, pages 4-
7).
We have carefully reviewed the entire record, including
all of the arguments and evidence advanced by both the
examiner and the appellant in support of their respective
positions. This review leads us to conclude that the
aforementioned § 103 rejection is not well founded.
Accordingly, we reverse. The reasons for our determination
follow.
Appeal No. 1997-2674
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Burton teaches a process for reducing the concentration
of nitrogen oxides, or other pollutants, in an effluent from
the combustion of a carbonaceous fuel (column 3, lines 44-47).
According to Burton, the apparatus 20 used to carry out the
process comprises a probe 21 comprising: (i) a supply conduit
24 for supplying and injecting a treatment fluid 28, such as a
solution, into a high temperature environment, such as the
effluent stream of a utility boiler 10; and (ii) an
atomization conduit 30 for supplying an atomization fluid 32
(figures 1-3; column 3, lines 61-66; column 6, lines 19-21).
Burton further states that the supply conduit 24 is coaxial
with and disposed within atomization conduit 30 and that it is
axially slidable within atomization conduit 30 so that end
portion 24a of supply conduit 24 can extend beyond the end 31
of atomization conduit 30, as illustrated in figures 2 and 3,
or portion 24a can be retracted into atomization conduit 30,
as illustrated by the phantom lines in figure 3 (column 6,
lines 39-46; column 6, lines 54-58). Regarding the purpose of
the axial slidability of supply conduit 24, Burton teaches
that this feature facilitates the independent control of both
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atomization (i.e., droplet size) and dispersion of fluid 28
throughout effluent 60 (i.e., distance of injection) and that
it can be provided by suitable means known to the skilled
artisan, such as by compression fitting 26 (column 6, lines
46-49; column 6, lines 59-61).
Burton further describes that the effluent flue conduit
additionally has a thermocouple for temperature measurement
(column 8, lines 7-9). Also, Burton states that the treatment
fluid 28 should be dispersed uniformly within effluent stream
60 at a point where effluent 60 is at a temperature effective
for pollutant reduction employing the desired additive at a
particular concentration and that, in the exemplary case of
droplets of an aqueous urea solution, the temperature will be
above about 1300EF with enhancers (column 5, lines 16-24).
In comparing Burton’s method against the subject matter
of appealed claim 9, we determine that Burton does not teach
the following element of appealed claim 9: “. . . when the
temperature of the gas is sensed to be within a selected
range, activating the conduit to insert the nozzle into the
gas through the opening and activating the conduit to spray
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reagent through the nozzle into the gas; and when the
temperature of the gas is sensed to be outside the selected
range, activating the conduit to withdraw the nozzle from the
gas and out of the opening, and deactivating the conduit so
that no reagent is supplied through the conduit to the nozzle”
(emphasis added).
Recognizing the differences between the applied prior art
and the subject matter of the appealed claims (answer, pages 5
and 6), the examiner alleges as follows:
One skilled in the art knowing that Burton
emphasizes adding nitrogen oxide inhibiting liquid
reagent (28) only when conditions are proper for
pollutant reduction (i.e., temperature of boiler gas
(60) above about 1,300EF) and known [sic, knowing]
that Burton at least provides a means to measure the
temperature of boiler gas (60) during operation
(i.e., the thermocouples), would have been motivated
to monitor the temperature of boiler gas (60) and
activate supply conduit (24) to add or stop the
addition of nitrogen oxide inhibiting liquid reagent
(28) in response to the monitored temperature where
the addition occurs if the temperature of boiler gas
(60) is above about 1,300EF and where no addition
occurs when the temperature of boiler gas (60) is
outside of this temperature range. [Answer, pp. 5-
6.]
Further, the examiner states:
With respect to moving supply conduit (24) out
of boiler gas (60) and out of opening (31) when
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supply conduit (24) is not adding nitrogen oxide
inhibiting liquid reagent (28), Burton teaches that
it is important in the art of treating boiler gases
that the temperature in the boiler gas not destroy
the structural integrity of nozzles and their
support
(col. 2, lines 34-36), and Burton teaches the
atomization conduit (30) (i.e., the housing
surrounding supply conduit (24)) is made from a heat
resistant material (col. 6, lines 19-25). Burton,
also teaches that supply conduit (24) is made of a
heat resistant material (col. 3, line 66, to col. 4,
line 2). Thus, it is considered important to Burton
that the temperature of the atmosphere of boiler
(10) not damage the integrity of supply conduit
(24). Therefore, it would have been obvious to a
person of ordinary skill in the art at the time the
invention was made to have moved supply conduit (24)
out of boiler gas (60) and out of opening (31) when
supply conduit (24) is not adding nitrogen oxide
inhibiting liquid reagent (28) (i.e., to have
retracted supply conduit (24) completely within
atomization conduit (30)) to prevent supply conduit
(24) from contacting the atmosphere of boiler (10)
for extended periods of time when such is not in use
where the material of atomization conduit (30) will
add further heat protection for supply conduit (24).
This will have the benefit of extending the life of
supply conduit (24) where Burton desires to prevent
premature heat damage to nozzles and their supports
and recognizes this damage to be a problem. [Answer,
pp. 6-7.]
We cannot agree. Under 35 U.S.C. § 103, the examiner
carries the initial burden of establishing a prima facie case
of obviousness. In re Piasecki, 745 F.2d 1468, 1471-72, 223
USPQ 785, 787-88 (Fed. Cir. 1984).
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Here, we determine that the examiner has not met this
burden because there is no teaching or suggestion in Burton
that supports the examiner’s rejection. Specifically, Burton
does not teach or suggest to a person skilled in the art to
measure the temperature and to use this temperature
information to activate supply conduit 24 for spraying
additive at certain temperatures and to deactivate the supply
conduit 24 so that no reagent is supplied through the conduit
at all other temperatures as in the appellant’s claimed
invention. At best, Burton might suggest using the
temperature information to control the concentration of the
additive or the size of the droplets being sprayed into the
boiler (column 5, lines 25-52). However, this cannot result
in the appellant’s claimed process in which the spraying of
additive is stopped altogether under certain temperatures.
While the examiner alleges that one of ordinary skill in
the art “would have been motivated to monitor the temperature
of boiler gas (60) and activate supply conduit (24) to add or
stop the addition of nitrogen oxide inhibiting liquid reagent
(28)” (examiner’s answer, pp. 5-6), we find that such an
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allegation is contrary to the actual teachings of Burton. In
particular, Burton teaches that, in the most typical
situation, the interior boiler 10 can be accessed only in the
area of the flame 15 and at an area above the flame, where the
temperatures at full load are typically within the range of
about 2,050EF and above (column 5, lines 29-37).
Additionally, Burton teaches that in the exemplary case of
aqueous urea solution, pollutant reduction can occur at
temperatures above about 1,300EF with enhancers and above
about 1,550EF without enhancers (column 5, lines 20-24). No
other evidence has been presented by the examiner to establish
that additives other than urea would not be effective at the
boiler temperatures disclosed in Burton. Given the
disclosures in Burton, we see no reason why one of ordinary
skill in the art would have been motivated to monitor the
temperature to activate or deactivate supply conduit 24 in the
manner as suggested by the examiner. That is, the examiner
has not established the requisite factual basis upon which to
conclude that a person of ordinary skill in the art would have
found any incentive or suggestion in the prior art to monitor
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the temperature for the purpose stated in the examiner’s
answer.
As to the retraction of supply conduit 24, the examiner’s
rationale is equally untenable. The examiner states that
it would have been obvious to a person of ordinary skill in
the art to move supply conduit 24 out of the boiler gas 60 and
out of opening 31 when supply conduit 24 is not adding
nitrogen oxide inhibiting reagent 28 to prevent supply conduit
24 from contacting the atmosphere of the boiler 10 for
extended periods of time and that, in doing so, the material
of atomization conduit 30 would provide further heat
protection for supply conduit 24 (examiner’s answer, pp. 6-7).
Again, however, there is no teaching or suggestion in Burton
to support the examiner’s rationale. Moreover, Burton teaches
the use of other means, such as the use of heat resistant
materials or a cooling fluid to counteract the high
temperature in the boiler (column 3, line 66 to column 4, line
2; column 7, lines 49-53). The examiner has not pointed to,
and we do not find any, evidence to indicate that a person of
ordinary skill in the art would have been led to modify
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Burton’s process in the manner as suggested by the examiner in
spite of Burton’s teachings regarding the use of heat
resistant materials or a cooling fluid to counteract the harsh
environment in the boiler.
Under these circumstances, we determine that Burton would
not have suggested the modification of Burton’s process in the
manner as proposed by the examiner. Because the examiner has
engaged in impermissible hindsight reconstruction, we reverse
the examiner’s rejection under 35 U.S.C. § 103 of claims 6, 7,
9, and 10 as unpatentable over Burton. W. L. Gore & Assoc. v.
Garlock, Inc., 721 F.2d 1540, 1553, 220 USPQ 303, 312-13 (Fed.
Cir. 1983)(“To imbue one of ordinary skill in the art with
knowledge of the invention in suit, when no prior art
reference or references of record convey or suggest that
knowledge, is to fall victim to the insidious effect of a
hindsight syndrome wherein that which only the inventor taught
is used against its teacher.”).
The decision of the examiner is reversed.
REVERSED
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Application No. 08/266,809
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JOHN D. SMITH )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
TERRY J. OWENS ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
ROMULO H. DELMENDO )
Administrative Patent Judge )
ROBERT J. EDWARDS
PATENT DEPT.
McDERMOTT INCORPORATED
P.O. BOX 60035
1450 POYDRAS ST.
NEW ORLEANS, LA 70160
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RHD/