DETAILED ACTION
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 .
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 10-13, 16-17, and 20-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Duarte-Escareno et al. (US 2004/0226406 A1, hereinafter “Duarte”).
Regarding claim 10, Duarte teaches a method and an integrated steel plant wherein the plant includes a coke oven, blast furnace, blast oxygen furnace converter, direct reduction shaft furnace, and an electric arc furnace to produce liquid steel (Duarte, [0001], [0004], [0011], [0018-0027], and Figure 1). Duarte teaches iron ore particles are red to reactor 36 to form direct reduced iron, i.e., sponge iron, and the DRI is discharged from the reactor and charged to the blast furnace 14 (Duarte, [0052]).
Duarte further teaches DRI produced with the use of coke oven gas and blast furnace top gas can be utilized as a metallic charge to the blast furnace or electric arc furnace (Duarte, [0011]). Duarte also teaches reducing gas 94 is withdrawn from reactor 36 after having reacted with iron oxides 76 and is eventually recycled to the blast furnace (Duarte, [0054]). Duarte teaches cold air 50 is heated in stoves 52 by heat exchange with refractory material inside stoves which store heat from combustion fuel gases 54 effluent from the reduction reactor 36 (Duarte, [0043]). Duarte teaches gas mixture 48 is fed into the blast furnace (Duarte, [0043] and Figure 1).
Duarte teaches iron ore, sinter, and fluxes are fed to the blast furnace where molten pig iron is produced by reduction of iron ore and sinter by carbon monoxide and hydrogen generated from the partial combustion of coke and hot air (Duarte, [0043]). Duarte additionally teaches molten pig iron 46 is further processed and converted into steel in a blast oxygen furnace converter by adjusting the carbon and other elements present in the composition of pig iron and scrap by blowing oxygen (Duarte, [0044]).
The method and integrated steel plant of Duarte corresponds to a method for producing steel in an integrated metallurgical plant of claim 10. Forming DRI from iron ore particles in a shaft furnace of Duarte corresponds to directly reducing iron ore to give sponge iron using at least one direct reduction reactor of claim 10. Melting DRI in an electric arc furnace of Duarte corresponds to melting the sponge iron to give one of pig iron and crude steel using at least one electric furnace of claim 10. Forming molten pig iron in a blast furnace of Duarte corresponds to smelting iron ore to give pig iron using at least one blast furnace of claim 10. Using the blast oxygen furnace converter to produce refined steel of Duarte corresponds to refining pig iron to give crude steel using at least one converter of claim 10.
The reducing gas withdrawn from the reactor of Duarte corresponds to discharging process gas from the direct reduction reactor of claim 10. The mixture of the heated air and combustion fuel gases from the reduction reactor and feeding this mixture into the blast furnace of Duarte corresponds to admixing the process gas at least partly to at least one of hot blast air and a charging material, the at least one of the hot blast air and the charging material being blown into the blast furnace of claim 10 and wherein the process gas is admixed at least partly directly to the at least one of the hot blast air and the charging material of claim 11.
Regarding claims 12 and 13, Duarte further teaches a main portion of the withdrawn reducing gas is de-watered 98 and sent as stream 99 to a compressor and passes through CO2 absorber 68 thereby increasing its reducing potential and eventually recycled (Duarte, [0054]). The de-watered gas of Duarte corresponds to wherein the process gas is first dehumidified and then admixed as dehumidified process gas at least partly to at least one of the hot blast air and the charging material of claim 12. The removal of CO2 of Duarte corresponds to removing CO2 fraction contained in the process gas or in the dehumidified process gas; and admixing the removed CO2 as carbon dioxide-free process gas at least partly to at least one of the hot blast air and the charging material of claim 13.
Regarding claims 16 and 17, Duarte teaches blast furnace gas is generated by partial combustion of carbon with air and removed from the blast furnace where a portion of the blast furnace gas is utilized to heat the reducing gas for the direct reduction reactor in heater 30 (Duarte, [0035-0036]). The use of blast furnace gas to heat the reducing gas that is supplied to the direct reduction heater of Duarte corresponds to wherein the process gas discharged from the blast furnace is provided at least partly as at least one of (i) fuel gas for firing reduction gas heater of the direct reduction reactor; and (ii) supplied at least partly to the blast furnace of claim 16 and wherein the process gas discharged from the blast furnace is provided at least partly as fuel gas for firing the reduction gas heater of the direct reduction reactor of claim 17.
Regarding claims 20 and 21, Duarte teaches blast furnace gas is generated by partial combustion of carbon with air and removed from the blast furnace where a portion of the blast furnace gas is utilized to heat the reducing gas for the direct reduction reactor in heater 30 (Duarte, [0035-0036]). Duarte also teaches reducing gas 94 is withdrawn from reactor 36 after having reacted with iron oxides 76 and is eventually recycled to the blast furnace (Duarte, [0054]). The use of blast furnace gas to heat the reducing gas that is supplied to the direct reduction heater and recycling reducing gas from the reactor to the blast furnace of Duarte corresponds to wherein at least two discharged process gases are provided at least partly as at least one of (i) fuel gas for firing the reduction gas heater of the direct reduction reactor; and (ii) supplied at least partly to the blast furnace of claims 20 and 21.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claims 15 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Duarte-Escareno et al. (US 2004/0226406 A1, hereinafter “Duarte”).
Regarding claim 15, Duarte teaches the integrated steel works comprises a coke oven in which coal is converted into coke by heating coal and separating volatile components as coke oven gas (Duarte, [0042]). Duarte also teaches as compared to blast furnace gas, coke oven gas has a wider use because of its relatively low distribution costs, and that blast furnace gas can be used to heat the reducing gas for the direct reduction reactor in heater 30 (Duarte, [0035-0038]). Given that BFG can be used to heat reducing gases and COG can be used for more applications, i.e., COG can also be used for the same applications, it would have been obvious to one of ordinary skill in the art that COG could also be used to heat the reducing gas as it has a low distribution cost, and thereby arrive at the present invention. The coke oven of Duarte corresponds to the cookery of claim 15. The potential use of the coke oven gas to heat the reducing gas of Duarte corresponds to wherein the process gas discharged from the cokery is at least one of (i) provided at least partly as fuel gas for firing the reduction gas heater of the direct reduction reactor; and (ii) is supplied at least partly to the blast furnace of claim 15.
Regarding claim 19, Duarte teaches blast furnace gas is generated by partial combustion of carbon with air and removed from the blast furnace where a portion of the blast furnace gas is utilized to heat the reducing gas for the direct reduction reactor in heater 30 (Duarte, [0035-0036]). Duarte also teaches reducing gas 94 is withdrawn from reactor 36 after having reacted with iron oxides 76 and is eventually recycled to the blast furnace (Duarte, [0054]). The use of blast furnace gas to heat the reducing gas that is supplied to the direct reduction heater and recycling reducing gas from the reactor to the blast furnace of Duarte corresponds to wherein at least two discharged process gases are provided at least partly as at least one of (i) fuel gas for firing the reduction gas heater of the direct reduction reactor; and (ii) supplied at least partly to the blast furnace of claim 19.
Claims 14 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Duarte as applied to claim 13 above, and further in view of Duarte-Escareno (WO 2020/245070 A1, hereinafter “WO070”).
Regarding claim 14, while Duarte teaches the use of an EAF to melt direct reduced iron (Duarte, [0011]), Duarte does not explicitly disclose process gas discharged from the electric furnace is at least one of (i) provided at least partly as fuel gas for firing a reduction gas heater of the direct reduction reactor; and (ii) supplied at least partly to the blast furnace.
With respect to the difference WO070 teaches methods and systems for producing steel in which the energy losses are significantly decreased by using the energy from the off gas of an EAF (WO070, Abstract and pg. 1, paragraph 6). WO070 teaches the hot gases produced from an electric melting furnace are used to produce steam and/or water, by recovering the heat from the hot gases (WO070, pg. 2, paragraphs 3-5). WO070 further teaches an electric power generator to produce electric energy utilizing steam from the heat recovery unit, in which the electricity is used in an electrolysis unit to produce hydrogen for the use in a direct reduction furnace (WO070, pg. 2, paragraph 1 and Figure 1).
As WO070 expressly teaches, the use of a heat recovery unit, electric power generator, and electrolysis unit significantly reduces the carbon footprint of the steelmaking process (WO070, pg. 4, paragraph 1).
Duarte and WO070 are analogous art as they are both drawn to steelmaking processes that include a direct reduction furnace and EAF (Duarte, [0011]; WO070 Figure 1).
In light of the motivation to use the hot gases from an EAF to produce electricity that is used in an electrolysis unit as taught in WO070 above, it therefore would have been obvious to one of ordinary skill in the art to use the electricity produced by the EAF hot gases of Duarte to heat the heater for reducing gases in order to significantly reduce the carbon footprint of the steelmaking process (WO070, pg. 4, paragraph 1), and thereby arrive at the present invention.
Regarding claim 18, Duarte teaches blast furnace gas is generated by partial combustion of carbon with air and removed from the blast furnace where a portion of the blast furnace gas is utilized to heat the reducing gas for the direct reduction reactor in heater 30 (Duarte, [0035-0036]). Duarte also teaches reducing gas 94 is withdrawn from reactor 36 after having reacted with iron oxides 76 and is eventually recycled to the blast furnace (Duarte, [0054]). The use of blast furnace gas to heat the reducing gas that is supplied to the direct reduction heater and recycling reducing gas from the reactor to the blast furnace of Duarte corresponds to wherein at least two discharged process gases are provided at least partly as at least one of (i) fuel gas for firing the reduction gas heater of the direct reduction reactor; and (ii) supplied at least partly to the blast furnace of claim 18.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DANIELLE CARDA whose telephone number is (571)270-1240. The examiner can normally be reached Monday-Friday 8:30-4:00 EST.
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/DANIELLE M. CARDA/Primary Examiner, Art Unit 1738