Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
DETAILED ACTION
Response to Arguments/Affidavit
Applicant's arguments and affidavit filed 12/1/2025 have been fully considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument/affidavit.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim 1 is rejected under 35 U.S.C. 103 as being unpatentable over Niemitz (US 2857148 A), hereinafter Niemitz, in view of Khinkis (US 5209187 A), hereinafter Khinkis, and further in view of Mirkovic (US 20040197239 A1), hereinafter Mirkovic.
Regarding claim 1, Niemitz discloses a method for operating a calcinator in a plant for producing cement clinker, in which lime, as hot meal, is freed of carbon dioxide and converted into burnt lime (“My invention relates to improvements in methods of firing rotary kilns, particularly with natural gas and to a burner for handling natural gas in the firing of such kilns for the burning and calcining of raw materials in the production of cement, lime and the like” column 1, line 15), the method comprising:
providing a gas burner (“A gas burner 26” column 4, line 3),
supplying methane-rich natural gas as a fuel to the gas burner wherein the gas burner has a central air supply pipe which is annularly encompassed by a gas supply pipe (“The gas burner 26, shown more in detail in Figs. 2, 3 and 4, comprises concentrically-arranged pipes 34 and 36 so mounted in spaced relation to provide an annular passageway 38 for combustible gas, for example, natural gas” column 4, line 25),
combusting the methane-rich natural gas in the gas burner such that a complete burnout takes place in the calcinator in the presence of carbon dioxide and hot meal (“the flame should extend into the kiln” column 5, line 67), and
wherein, in a region of a mixing of fuel and air, an annularly disposed group of nozzles, forming a spiral vortex, is arranged, which mix the fuel with the air (“Natural gas, for example, is supplied under pressure through the valve connection 40 to the annular space 38 and flows in the form of an annular jet or stream through the passageway 69 and as individual jets 80 through the multiplicity of nozzles 76. The jets 80 are directed in spiral fashion, as shown in Fig. 4, into the stream of primary air issuing through the pipe 36, where the gas jets produce a whirling spiral action and the gas is burned” column 5, line 12), and wherein the process further comprises:
providing a control device in the form of a throttle valve, which, by an adjustment of the supplied air flow and fuel flow, maintains an air/fuel ratio λ (“combustible gas, for example, natural gas delivered from a gas main under pressure through a contrcl valve 40. Primary air for supporting combustion is delivered into the pipe 36 through a connection 42 Housing a control damper operable by a handle 44” column 4, line 28) .
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Niemitz does not disclose:
an oxygen-impoverished environment, an oxygen concentration of which is insufficient for supporting a complete combustion,
a sub-stoichiometric combustion takes place in the gas burner, conditioning the fuel as a result of the sub-stoichiometric combustion, and
maintaining an air/fuel ratio λ in a range of 0.05 to 0.3,
wherein the control device, with a closed-loop control device with a control loop, sets the desired λ value via at least one of a measured temperature in a combustion chamber or a spectrometrically measured gas concentration.
However, Khinkis teaches:
an oxygen-impoverished environment, an oxygen concentration of which is insufficient for supporting a complete combustion,
a sub-stoichiometric combustion takes place in the gas burner, conditioning the fuel as a result of the sub-stoichiometric combustion, and
maintaining an air/fuel ratio λ in a range of 0.05 to 0.3 (“Approximately 30% to 90% of the stoichiometric requirement of combustion air, that is, primary combustion air, is introduced into the cyclonic first stage producing reducing primary combustion zone 43” column 6, line 27 and “partially combusted gases from primary combustion zone 43 contain mostly CO and
H
2
species” column 9, line 34).
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In view of the teachings of Khinkis, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to include an oxygen-impoverished environment, an oxygen concentration of which is insufficient for supporting a complete combustion, a sub-stoichiometric combustion takes place in the gas burner, conditioning the fuel as a result of the sub-stoichiometric combustion, and maintaining an air/fuel ratio λ in a range of 0.05 to 0.3 as is taught in Khinkis, in the method disclosed by Niemitz because “reducing conditions suppress thermal NOx formation in the primary combustion zone” (column 9, line 25) and “Because partially combusted gases from primary combustion zone 43 contain mostly CO and
H
2
species, second stage combustion can be efficiently accomplished with very low excess air in a small combustion chamber. Low excess air and the absence of high peak temperatures in secondary combustion zone 44 minimizes NOx formation” (column 9, line 34). Therefore, operating the burner of Niemitz in an oxygen impoverished environment will reduce NOx.
Niemitz, as modified by Khinkis, does not disclose wherein the control device, with a closed-loop control device with a control loop, sets the desired λ value via at least one of a measured temperature in a combustion chamber or a spectrometrically measured gas concentration.
However, Mirkovic teaches wherein the control device, with a closed-loop control device with a control loop, sets the desired λ value via at least one of a measured temperature in a combustion chamber or a spectrometrically measured gas concentration (“a temperature sensor positioned within the combustion zone, capable of measuring the temperature of at least one point within the combustion zone; and a control system, comprising: a processor to which the temperature sensor is capable of reporting the measured temperature; and an air flow adjustment apparatus controlled by the processor and capable of adjusting the flow rate of air to the combustion zone in response to the reported temperature” abstract).
In view of Mirkovic’s teachings, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to include wherein the control device, with a closed-loop control device with a control loop, sets the desired λ value via a measured temperature in a combustion chamber as taught in Mirkovic, in the method disclosed by Niemitz because the court held that broadly providing an automatic or mechanical means to replace a manual activity which accomplished the same result is not sufficient to distinguish over the prior art In re Venner, 262 F.2d 91, 95, 120 USPQ 193, 194 (CCPA 1958). In this case, the difference between the claims and Niemitz is the provision of automatic control of the air/fuel ratio.
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Niemitz, in view of Khinkis, in view of Mirkovic, and further in view of Freze (US 4128388 A), hereinafter Freze.
Regarding claim 3, Niemitz as modified by Khinkis and Mirkovic, discloses the method as claimed in claim 1.
Niemitz as modified by Khinkis and Mirkovic, does not disclose providing at least one additional pilot burner which, in the region of the combustion chamber, reliably ignites the mixture of injected fuel and oxidation means.
However, Freze teaches providing at least one additional pilot burner which, in the region of the combustion chamber, reliably ignites the mixture of injected fuel and oxidation means (“It is also an important requirement of the burner design to provide a strong stable pilot flame for reliable ignition of the main combustion gases” column 2, line 13).
In view of Freze’s teachings, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to include providing at least one additional pilot burner which, in the region of the combustion chamber, reliably ignites the mixture of injected fuel and oxidation means as is taught in Freze, in the method disclosed by Niemitz because Freze states that the pilot provides reliable ignition. Therefore, including the pilot will improve reliability of ignition in Niemitz.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Niemitz, in view of Khinkis, in view of Mirkovic, and further in view of Brola (US 2929442 A), hereinafter Brola.
Regarding claim 4, Niemitz as modified by Khinkis and Mirkovic, discloses the method as claimed in claim 1.
Niemitz as modified by Khinkis and Mirkovic, does not disclose wherein inner walls of the gas burner have at least one air suction nozzle, by means of which, sucked-in ambient air flows into the gas burner in the region of the walls of said burner and, as a result, cools the inner walls of the gas burner.
However, Brola teaches wherein inner walls of the gas burner have at least one air suction nozzle, by means of which, sucked-in ambient air flows into the gas burner in the region of the walls of said burner and, as a result, cools the inner walls of the gas burner (“To prevent carbonaceous deposits within the furnace tube 22, part of the secondary air is introduced tangentially into the chamber and is directed towards the inner wall surface of the furnace tube by the action of deflector baffles 50 secured to the cup member 44. The rotational movement of the deflectors causes the air to swirl around the wall of the furnace tube thereby to burn up progressively any deposits which may tend to settle thereon, while simultaneously protecting the refractory material by a film of cool air” column 3, line 53).
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In view of Brola’s teachings, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to include wherein inner walls of the gas burner have at least one air suction nozzle, by means of which, sucked-in ambient air flows into the gas burner in the region of the walls of said burner and, as a result, cools the inner walls of the gas burner as is taught in Brola, in the method disclosed by Niemitz because Brola states that this feature prevents carbonaceous deposits and cools the inner walls of the gas burner. Therefore, including the feature of Brola will prevent deposits in and protect the walls of Niemitz.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Falla (US 2007676 A) “It has for an object the more effective distribution of heat within the kiln, more particularly in connection with the operation of the kiln under conditions involving initially incomplete combustion of the fuel with subsequent complete combustion thereof at a point intermediate the ends of the kiln” column 1, line 5
Culliford (US 4541346 A) “Starved air combustion of this type ensures that the burning bed of material in the primary combustion chamber reaches a very high temperature, giving complete burn-out and, in the case of contaminated waste, a sterile and non-toxic ash” column 2, line 41
Leger (US 5572938 A) “After passage through a portion of the kiln length, generally from about 3 to 5 kiln diameters, this lanced secondary oxygen reacts with incompletely combusted fuel from the main combustion reaction to complete the combustion in a deeply staged manner so as to improve fuel efficiency and increase clinker production and reduce emissions of carbon monoxide, hydrocarbons and sulfur dioxide” column 4, line 44
Nick (US 20060112639 A1) “The most effective heating scheme, however, is to combust (as nearly completely as possible) the hydrocarbon stream with near-stoichiometric or better yet, significantly sub-stoichiometric concentration levels of oxygen. This is done for five reasons: [0070] 1. Combustion heat will provide the necessary (and maximum) heat release to the gas leaving the burner. [0071] 2. Water vapor in the superheated combustion products will be adequate at least for steam gasification reactions (reactions 2 and 3 listed in earlier discussions) with the pyrolyticly-generated char. [0072] 3. Oxygen content of the gas in the reactor can be maintained preferably at zero but no greater than 1000 ppm by weight [0073] 4. CO content will be maximized, while CO.sub.2 is minimized, to promote the rapid reactions in the gasification section. [0074] 5. Enough product water vapor in the superheated combustion products can be made available for partial steam reforming of the pyrolysis products”
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/LOGAN P JONES/Examiner, Art Unit 3762