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 .
Election/Restrictions
Applicant's election with traverse of Group I, Species A1, Species B1 and Species C1 in the reply filed on 08/07/2026 is acknowledged. The traversal is on the ground(s) that US'406 fails to disclose that the reducing gas used in the DRI process results from the gasification of solid waste fuels, and that the produced DRI is used to produce molten metal in an electric arc furnace. This is not found persuasive. US’406 discloses using DRI to produce molten metal in an electric arc furnace ([0011]; [0059]). US’406 in view of JP’029 (JP3808029B2) teaches that the reducing gas used in the DRI process includes syngas resulting from gasification of solid waste fuels ([0029] of JP’029).
The applicants further argued that claim Species A1 and reads on claim 23 as "wherein the reduction top gas is at least partly recycled within the direct reduction plant as part of the reducing gas" not at all precluded when "the reduction top gas is at least partly used as reductant in the hot metal production." The Examiner withdrew Group A and Group B Species restriction requirements; however, the examiner maintains Group C Species restriction requirement because Claims 29 and 30 recite mutually exclusive material. The requirement is still deemed proper and is therefore made FINAL. Claims 30 and 32 are withdrawn. Claims 17-29 and 31 are examined herein.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 17-31 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The terms “hot metal” and “hot blast” in claims 17-18, 20-21, 25 and 29 are relative terms which render the claim indefinite. The terms “hot metal” and “hot blast” are not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Appropriate correction is required.
Claim 19 recites green hydrogen. The meaning of green hydrogen is unclear. Appropriate correction is required.
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.
Claims 17-18, 20, 23-24 and 27-28 are rejected under 35 U.S.C. 103 as being unpatentable over US’406 (US 2004/0226406), and further in view of JP’029 (JP3808029B2).
Regarding claim 17, US’406 teaches a method of making steel, comprising: producing direct reduced iron and a reduction top gas in a direct reduction plant using a reducing gas including a syngas resulting from the gasification of coal and a gas from blast furnace top gas ([0011]; [0038]; [0041]; [0047] to [0054]); producing molten pig iron and a blast furnace top gas in a blast furnace using a hot blast, the blast furnace top gas being partly used in the direct reduction plant to heat the reducing gas ([0033] to [0036]; [0043]); and producing molten steel and electric furnace gas in an electric furnace using the produced direct reduced iron ([0011]; [0027]; [0059]).
US’406 does not disclose making direct reduced iron using a syngas from gasification of solid waste fuel. JP’029 teaches a method of making direct reduced iron and discloses that reducing gas comprising gas from gasification of coal and a gas from gasification of solid waste fuel is used in the manufacturing process to save cost ([0019]; [0020]; [0029]). Thus, it would be obvious to one of ordinary skill in the art to use reducing gas from gasification coal and gasification of solid waste fuel as taught by JP’029 in the direct reduction process of US’406 in order to save cost as disclosed by JP’029.
Regarding claim 18, US’406 discloses producing coke and a coke oven gas in a coke plant ([0038]), the coke being charged into the blast furnace for the hot metal production step ([0043]; Fig. 1), the coke oven gas being at least partly used as the reducing gas in the direct reduction plant ([0011]), which meets the limitation recited in claim 18.
Regarding claim 20, US’406 discloses that coke oven gas can be charged to the blast furnace to decrease its consumption of coke and/or powdered coal injection in producing hot metal ([0004]), which meets the limitation recited in claim 20.
Regarding claim 23, US’406 discloses that the reduction top gas is at least partly recycled within the direct reduction plant as part of the reducing gas ([0054]), which meets the limitation recited in claim 23.
Regarding claim 24, US’406 in view of JP’029 is silent on the composition of syngas. However, JP’029 discloses that the syngas is produced by gasification of plastic or wood chips ([0029]; [0030]), the same solid waste as disclosed in instant Specification. “Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established.” In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01 I. Thus, one of ordinary skill in the art would expect that the syngas disclosed by US’406 in view of JP’029 to meet the recited composition limitation in claim 24.
Regarding claim 27, blast furnace gas is utilized to heat the reducing gas for the direct reduction reactor ([0036]), which meets the limitation recited in claim 27.
Regarding claim 28, JP’029 discloses gasification of solid waste fuel such as plastic, wood chips and biomass ([0027] to [0030]). US’406 discloses that blast furnace gas can be used as fuel in coke oven for gasification of coal ([0036] to [0040]). It would be obvious to one of ordinary skills in the art that blast furnace gas can also be used as fuel for gasification of plastic, biomass and wood chips.
Claims 19 and 26 is rejected under 35 U.S.C. 103 as being unpatentable over US’406 (US 2004/0226406) in view of JP’029 (JP3808029B2), as applied to claim 17 above, and further in view of US’978 (US 2016/0304978).
Regarding claim 19, JP’029 discloses that the reducing gas obtained from gasification of solid waste contains CO and H2 and the reduction potential is low ([0026] to [0031]). US’406 in view of JP’029 does not disclose that the reducing gas further includes green hydrogen gas.
US’978 teaches a method of producing iron and discloses that hydrogen produced by electrolysis of water is added to reducing gas to adjust the H2 content to desired value (Abstract; [0017] to [0021]). It’s well-known to one of ordinary skills in the art that increasing H2 content in reducing gas increases reduction potential of the reducing gas. Thus, it would be obvious to one of ordinary skill in the art to add H2 produced by electrolysis of water as taught by US’978 to the reducing gas in the process of US’406 in view of JP’029 in order to increase the H2 content and the reduction potential of the reducing gas.
Regarding claim 26, US’406 in view of JP’029 does not disclose that the blast furnace top gas is sent to a chemical production unit. US’978 teaches a method of producing iron and discloses that the blast furnace top gas is used for producing chemical products in a chemical plant to improve cost-effectiveness and to reduce cost for steel production (Abstract; [0009]; [0012] to [0021]). Thus, it would be obvious to one of ordinary skill in the art to use blast furnace top gas for producing chemicals in a chemical plant as taught by US’978 in the process of US’406 in view of JP’029 in order to improve cost-effectiveness and to reduce cost for steel production as disclosed by US’978.
Claims 21 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over US’406 (US 2004/0226406) in view of JP’029 (JP3808029B2), as applied to claim 17 above, and further in view of US’526 (US 2024/0360526).
Regarding claims 21 and 22, US’406 in view of JP’029 does not disclose that the reduction top gas is at least partly used as reductant in the hot metal production. US’526 teaches a method of producing iron and discloses that direct reduction furnace top gas is used as reducing gas in a blast furnace to reduce coke consumption ([0012] to [0030]). Thus, it would be obvious to one of ordinary skill in the art to inject direct reduction furnace top gas to blast furnace as taught by US’526 in the process of US’406 in view of JP’029 in order to reduce coke consumption as disclosed by US’526.
Claim 25 is rejected under 35 U.S.C. 103 as being unpatentable over US’406 (US 2004/0226406) in view of JP’029 (JP3808029B2), as applied to claim 17 above, and further in view of US’364 (US 2015/0068364).
Regarding claim 25, US’406 in view of JP’029 does not disclose that the blast furnace top gas is recycled within the blast furnace as hot blast. US’364 teaches a method of producing iron and discloses that the blast furnace top gas is recycled within the blast furnace as hot blast to reduce coke consumption (Abstract; [0017] to [0021]). Thus, it would be obvious to one of ordinary skill in the art to recycle blast furnace top gas to blast furnace as hot blast as taught by US’364 in the process of US’406 in view of JP’029 in order to reduce coke consumption as disclosed by US’364.
Claim 29 is rejected under 35 U.S.C. 103 as being unpatentable over US’406 (US 2004/0226406) in view of JP’029 (JP3808029B2), as applied to claim 17 above, and further in view of US’008 (US 2014/0077008).
Regarding claim 29, US’406 in view of JP’029 does not disclose that the hot metal from blast furnace is used in electric furnace to produce molten metal. US’008 teaches a method of producing iron and discloses that the pig iron from blast furnace is used to produce steel, usually with an electric arc furnace, by burning off excess carbon and adding certain metal alloys (Abstract; [0004]). Thus, it would be obvious to one of ordinary skill in the art to use pig iron from blast furnace in an electric arc furnace as taught by US’008 in the process of US’406 in view of JP’029 in order to produce steel as disclosed by US’008.
Claim 31 is rejected under 35 U.S.C. 103 as being unpatentable over US’406 (US 2004/0226406) in view of JP’029 (JP3808029B2), as applied to claim 17 above, and further in view of US’314 (US 2024/0191314).
Regarding claim 31, US’406 in view of JP’029 discloses that the syngas can be produced from biomass ([0029] and [0030] of JP’029), which meets the limitation that step “a” is supplied with renewable energy.
US’406 discloses using air for production of pig iron in blast furnace (Fig. 1), which meets the limitation that step “b” is supplied with renewable energy.
US’406 in view of JP’029 does not disclose that step “c” is supplied with renewable energy.
US’314 teaches a method of producing steel and discloses that an electric arc furnace is supplied by renewable energy to reduce CO2 release (Abstract; [0044]; [0067]). Thus, it would be obvious to one of ordinary skill in the art to use an electric arc furnace operated on renewable energy as taught by US’314 in the process of US’406 in view of JP’029 in order to reduce CO2 release as disclosed by US’314.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Xiaowei Su whose telephone number is (571)272-3239. The examiner can normally be reached 8:00-5:00.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Hendricks can be reached at 5712721401. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/XIAOWEI SU/Primary Examiner, Art Unit 1733
Prosecution Insights