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 .
Applicant amended Claims 9 and 12-13. Applicant added Claims 20-22. Claim 19 is cancelled. Support for the amendments and new claim are found in the original filing. No new matter is presented.
Election/Restrictions
Claims 1-8 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected method, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 10/10/2025.
Continued Examination Under 37 CFR 1.11
Receipt is acknowledged of a request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e) and a submission, filed on 06/11/2026.
Claim Rejections - 35 USC § 102
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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 9-10 and 12-16, are rejected under 35 U.S.C. 102(a)(1) and (a)(2) as being anticipated by NPL Viitasaari, "Utilisation possibilities of biochar produced by pyrolysis." (2021).
Regarding Claims 9-10 and 12-13, NPL Viitasaari discloses a system for producing a gas feed containing bio-oil and/or fast pyrolysis biochar and feeding the stream as fuel to a blast furnace for iron ore reduction to produce metallic iron (Abstract) (Figs. 1, 9, Pages 7, 31), meeting the limitations of the instant Claims.
Regarding Applicant’s Arguments, the blast furnace recited in instant Claim 1 is part of a system that need only be capable of gasifying a source of fuel comprising at least one of bio-oil or fast pyrolysis biochar. The claims are drawn to a system, and not to a method. Therefore, the teachings of NPL Viitasaari meet the limitations of the instant Claims. Regarding the specifications of biochar being produced by fast pyrolysis and having at least one of a molar ratio of hydrogen to carbon from about 0.5 to about 0.8 or a volatile matter content of at least about 20%, these features are not required to meet the limitation of a system for reducing iron oxide comprising a source of fuel and a blast furnace configured to gasify the fuel and reduce iron. A material or article worked upon does not limit apparatus claims. See MPEP 2115. "Inclusion of the material or article worked upon by a structure being claimed does not impart patentability to the claims." In re Otto, 312 F.2d 937, 136 USPQ 458, 459 (CCPA 1963); see also In re Young, 75 F.2d 996, 25 USPQ 69 (CCPA 1935). In the instant case, the material acted upon (biofuel) is not required or critical for the function of the apparatus, the claimed system.
Regarding Claim 14, NPL Viitasaari discloses blending biochar with coal for use as fuel in blast furnace injection at (Page 33), meeting the limitations of the instant Claim.
Regarding Claim 15, NPL Viitasaari discloses the use of liquid bio-oil as fuel (Page 11), meeting the limitations of the instant Claim.
Regarding Claim 16, NPL Viitasaari discloses feeding fuel through inputs (meeting the limitation for a plurality of lines) configured to feed the fuel through hot blast through a plurality of tuyeres in the blast furnace (Page 30), meeting the limitations of the instant Claim.
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.
Claims 11 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari.
Regarding Claim 11, NPL Viitasaari teaches the use of bio-oil as blast furnace fuel wherein the bio-oil has a water content of up to 20% water (Page 12), overlapping and meeting the limitation of the instantly claimed range of a water content less than about 10% by mass.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize as fuel a bio-oil with a water content in the claimed range of less than about 10% by mass based on the teachings of NPL Viitasaari at (Pages 5, 11-12) that such oils with a water content of up to 20% by mass, overlapping the claimed range of water content, are useful as feedstock to a blast furnace.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Regarding Claim 20, As set forth above, NPL Viitasaari discloses a system for producing a gas feed containing bio-oil and/or fast pyrolysis biochar and feeding the stream as fuel to a blast furnace for iron ore reduction to produce metallic iron (Abstract) (Figs. 1, 9, Pages 7, 31).
NPL Viitasarri further teaches an exemplary biochar collected from fast pyrolysis and presenting a H/C ratio (molar ratio of hydrogen to carbon of 0.49), meeting the limitations of the instant Claim for a molar ratio of hydrogen to carbon of about 0.5 to about 0.8.
A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap but are merely close. See MPEP 2144.05(I). Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari as applied to Claims 9-10 and 12-16 above further in view of NPL Dimofte et al. "Hot air distribution through main bustle pipe on the tuyeres of a blast furnace." Proceedings of the 3rd International Conference of Thermal Equipment, Renewable Energy and Rural Development-TE-RE-RD. 2014.
Regarding Claim 17, NPL Viitasaari discloses the limitations set forth above and further teaches hot blast injection e.g. at (Page 30) but NPL Viitasaari does not expressly teach a ring-shaped manifold disposed around the blast furnace and configured to feed the fuel to a plurality of tuyeres in the blast furnace.
However, NPL Dimofte et al. teaches that the use of a ring-shaped bustle pipe (meeting the limitation for a manifold) disposed around a blast furnace and configured to feed fuel to a plurality of tuyeres in the blast furnace is beneficial for controlling the blast volume within the furnace.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to dispose the ring-shaped bustle pipe (meeting the limitation for a manifold) configured to feed fuel to a plurality of tuyeres in the blast furnace of NPL Viitasaari in order to control the hot blast volume. One of ordinary skill in the art would have been motivated by desire to increase uniformity of fuel distribution to utilize the ring-shaped manifold of NPL Dimofte et al., meeting the limitations of the instant Claim.
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari as applied to Claims 9-10 and 12-16 above further in view of Dong et al. CN 117431079 A.
Regarding Claim 18, NPL Viitasaari discloses the limitations set forth above and further teaches achieving a 100% coal replacement ratio with biochar e.g. at (Page 31) but NPL Viitasaari does not expressly teach a replacement ratio of bio-oil.
However, Dong et al. ’079 expressly teaches gasified bio-oil as blast furnace fuel with a 1:1 replacement ratio [0012, 0023]. Insofar as the system disclosed by NPL Viitasaari reads on the system of Claim 15, it would have been obvious to one having ordinary skill in the art at the time of filing the invention to achieve a 100% coal replacement ratio of bio-oil fuel based on the teachings of Dong et al. ‘079 at [0012, 0023].
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to achieve a 1:1 replacement of bio-oil in the blast furnace of NPL Viitasaari in order to reduce costs and save energy, based on the teachings of NPL Dong et al. ‘079 at [0026] meeting the limitations of the instant Claim. See MPEP 2141.01(a) I. “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Claims 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari as applied to Claims 9-10 and 12-16 above further in view of Sun et al. “Comparative Study on the Performance and Mechanism of Adsorption-Oriented Phosphorous-Modified High-Efficiency and Durable Activated Biochar from Fast Pyrolysis.” (2023).
Regarding Claims 9-10 and 12-13, As set forth above, NPL Viitasaari discloses a system for producing a gas feed containing bio-oil and/or fast pyrolysis biochar and feeding the stream as fuel to a blast furnace for iron ore reduction to produce metallic iron (Abstract) (Figs. 1, 9, Pages 7, 31).
NPL Viitasarri does not expressly teach biochar produced by fast pyrolysis with a volatile matter content of at least about 20%.
However, Sun et al. teaches exemplary biochars formed from fast pyrolysis having volatile matter contents of 24.1% and 83.46%, both overlapping the instantly claimed ranges of about 20% and about 24%.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize a fast pyrolysis produced biochar having a volatile matter content of 24% or 83.46% in the system of NPL Viitasarri in order to improve production efficiency, meeting the limitations of the instant Claim.
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Claims 9-16 and 21-22 are additionally and alternatively rejected under 35 U.S.C. 103 over NPL Viitasaari in view of Sun et al.
Regarding Claims 9-10, 12-13, and 21-22, NPL Viitasaari teaches a system for producing a gas feed containing bio-oil and/or fast pyrolysis biochar and feeding the stream as fuel to a blast furnace for iron ore reduction to produce metallic iron (Abstract) (Figs. 1, 9, Pages 7, 31).
NPL Viitasaari teaches the use of fast pyrolysis biochar e.g. at (Page 8) but does not expressly teach biochar produced by fast pyrolysis with a volatile matter content of at least about 20%.
However, NPL Sun et al. teaches exemplary biochars formed from fast pyrolysis having volatile matter contents of 24.1% and 83.46% (Figure 2., Page 6), both overlapping the instantly claimed ranges of about 20% and about 24%.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize a fast pyrolysis produced biochar having a volatile matter content of 24% or 83.46% in the system of NPL Viitasaari in order to improve production efficiency, based on the teachings of NPL Sun et al. at (Abstract, Pages 5-6), meeting the limitations of the instant Claim.
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding Claim 11, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches the use of bio-oil as blast furnace fuel wherein the bio-oil has a water content of up to 20% water (Page 12), overlapping and meeting the limitation of the instantly claimed range of a water content less than about 10% by mass.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize as fuel a bio-oil with a water content in the claimed range of less than about 10% by mass based on the teachings of NPL Viitasaari at (Pages 5, 11-12) that such oils with a water content of up to 20% by mass, overlapping the claimed range of water content, are useful as feedstock to a blast furnace.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Regarding Claim 14, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches blending biochar with coal for use as fuel in blast furnace injection at (Page 33), meeting the limitations of the instant Claim.
Regarding Claim 15, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches the use of liquid bio-oil as fuel (Page 11), meeting the limitations of the instant Claim.
Regarding Claim 16, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches feeding fuel through inputs (meeting the limitation for a plurality of lines) configured to feed the fuel through hot blast through a plurality of tuyeres in the blast furnace (Page 30), meeting the limitations of the instant Claim.
Claim 17 is additionally and alternatively rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari in view of NPL Sun et al. as applied to Claims 9-16 above further in view of NPL Dimofte et al.
Regarding Claim 17, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches hot blast injection e.g. at (Page 30) but NPL Viitasaari does not expressly teach a ring-shaped manifold disposed around the blast furnace and configured to feed the fuel to a plurality of tuyeres in the blast furnace.
However, NPL Dimofte et al. teaches that the use of a ring-shaped bustle pipe (meeting the limitation for a manifold) disposed around a blast furnace and configured to feed fuel to a plurality of tuyeres in the blast furnace is beneficial for controlling the blast volume within the furnace.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to dispose the ring-shaped bustle pipe (meeting the limitation for a manifold) configured to feed fuel to a plurality of tuyeres in the blast furnace of NPL Viitasaari in order to control the hot blast volume. One of ordinary skill in the art would have been motivated by desire to increase uniformity of fuel distribution to utilize the ring-shaped manifold of NPL Dimofte et al., meeting the limitations of the instant Claim.
Claim 18 is additionally and alternatively rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari in view of NPL Sun et al. as applied to Claims 9-16 above further in view of Dong et al. CN 117431079 A.
Regarding Claim 18, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches achieving a 100% coal replacement ratio with biochar e.g. at (Page 31) but NPL Viitasaari does not expressly teach a replacement ratio of bio-oil.
However, Dong et al. ’079 expressly teaches gasified bio-oil as blast furnace fuel with a 1:1 replacement ratio [0012, 0023]. Insofar as the system disclosed by NPL Viitasaari reads on the system of Claim 15, it would have been obvious to one having ordinary skill in the art at the time of filing the invention to achieve a 100% coal replacement ratio of bio-oil fuel based on the teachings of Dong et al. ‘079 at [0012, 0023].
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to achieve a 1:1 replacement of bio-oil in the blast furnace of NPL Viitasaari in order to reduce costs and save energy, based on the teachings of NPL Dong et al. ‘079 at [0026] meeting the limitations of the instant Claim. See MPEP 2141.01(a) I. “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Claim 20 is additionally and alternatively rejected under 35 U.S.C. 103 over NPL Viitasaari in view of NPL Sun et al. as applied to Claims 9-16 above further in view of f NPL Kim et al. “Influence of pyrolysis temperature on physiochemical properties of biochar obtained from the fast pyrolysis of pitch pine (Pinus rigida).” (2012).
Regarding Claim 20, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches an exemplary biochar collected from fast pyrolysis and presenting a H/C ratio (molar ratio of hydrogen to carbon of 0.49)(Table 5., Page 24), meeting the limitations of the instant Claim for a molar ratio of hydrogen to carbon of about 0.5 to about 0.8.
A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap but are merely close. See MPEP 2144.05(I). Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Nonetheless, NPL Kim et al. expressly teaches an exemplary fast pyrolysis biochar having an atomic H/C ratio of 0.6 (Fig. 1, Page 160), lying within the instantly claimed range of a molar ratio of hydrogen to carbon from about 0.5 to about 0.8.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize a fast pyrolysis biochar with an H/C ratio of 0.6 in the system of NPL Viitasaari in order to achieve a highly ordered structure based on the teachings of NPL Kim et al. at (Abstract, Pages 159-160), meeting the limitations of the instant Claim.
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). See MPEP 2141.01(a) I. “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Claims 9-16 and 20 are additionally and alternatively rejected under 35 U.S.C. 103 over NPL Viitasaari in view of NPL Kim et al.
Regarding Claims 9-10, 12-13, and 20, NPL Viitasaari teaches a system for producing a gas feed containing bio-oil and/or fast pyrolysis biochar and feeding the stream as fuel to a blast furnace for iron ore reduction to produce metallic iron (Abstract) (Figs. 1, 9, Pages 7, 31).
NPL Viitasaari further teaches an exemplary biochar collected from fast pyrolysis and presenting a H/C ratio (molar ratio of hydrogen to carbon of 0.49) (Table 5., Page 24), meeting the limitations of the instant Claim for a molar ratio of hydrogen to carbon of about 0.5 to about 0.8.
A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap but are merely close. See MPEP 2144.05(I). Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Nonetheless, NPL Kim et al. expressly teaches an exemplary fast pyrolysis biochar having an atomic H/C ratio of 0.6 (Fig. 1, Page 160), lying within the instantly claimed range of a molar ratio of hydrogen to carbon from about 0.5 to about 0.8.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize a fast pyrolysis biochar with an H/C ratio of 0.6 in the system of NPL Viitasaari in order to achieve a highly ordered structure based on the teachings of NPL Kim et al. at (Abstract, Pages 159-160), meeting the limitations of the instant Claim.
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). See MPEP 2141.01(a) I. “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Regarding Claim 11, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches the use of bio-oil as blast furnace fuel wherein the bio-oil has a water content of up to 20% water (Page 12), overlapping and meeting the limitation of the instantly claimed range of a water content less than about 10% by mass.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize as fuel a bio-oil with a water content in the claimed range of less than about 10% by mass based on the teachings of NPL Viitasaari at (Pages 5, 11-12) that such oils with a water content of up to 20% by mass, overlapping the claimed range of water content, are useful as feedstock to a blast furnace.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Regarding Claim 14, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches blending biochar with coal for use as fuel in blast furnace injection at (Page 33), meeting the limitations of the instant Claim.
Regarding Claim 15, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches the use of liquid bio-oil as fuel (Page 11), meeting the limitations of the instant Claim.
Regarding Claim 16, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches feeding fuel through inputs (meeting the limitation for a plurality of lines) configured to feed the fuel through hot blast through a plurality of tuyeres in the blast furnace (Page 30), meeting the limitations of the instant Claim.
Claim 17 is additionally and alternatively rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari in view of NPL Kim et al. as applied to Claims 9-16 and 20 above further in view of NPL Dimofte et al.
Regarding Claim 17, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches hot blast injection e.g. at (Page 30) but NPL Viitasaari does not expressly teach a ring-shaped manifold disposed around the blast furnace and configured to feed the fuel to a plurality of tuyeres in the blast furnace.
However, NPL Dimofte et al. teaches that the use of a ring-shaped bustle pipe (meeting the limitation for a manifold) disposed around a blast furnace and configured to feed fuel to a plurality of tuyeres in the blast furnace is beneficial for controlling the blast volume within the furnace.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to dispose the ring-shaped bustle pipe (meeting the limitation for a manifold) configured to feed fuel to a plurality of tuyeres in the blast furnace of NPL Viitasaari in order to control the hot blast volume. One of ordinary skill in the art would have been motivated by desire to increase uniformity of fuel distribution to utilize the ring-shaped manifold of NPL Dimofte et al., meeting the limitations of the instant Claim.
Claim 18 is additionally and alternatively rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari in view of NPL Kim et al. as applied to Claims 9-16 and 20 above further in view of Dong et al. CN 117431079 A.
Regarding Claim 18, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari further teaches achieving a 100% coal replacement ratio with biochar e.g. at (Page 31) but NPL Viitasaari does not expressly teach a replacement ratio of bio-oil.
However, Dong et al. ’079 expressly teaches gasified bio-oil as blast furnace fuel with a 1:1 replacement ratio [0012, 0023]. Insofar as the system disclosed by NPL Viitasaari reads on the system of Claim 15, it would have been obvious to one having ordinary skill in the art at the time of filing the invention to achieve a 100% coal replacement ratio of bio-oil fuel based on the teachings of Dong et al. ‘079 at [0012, 0023].
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to achieve a 1:1 replacement of bio-oil in the blast furnace of NPL Viitasaari in order to reduce costs and save energy, based on the teachings of NPL Dong et al. ‘079 at [0026] meeting the limitations of the instant Claim. See MPEP 2141.01(a) I. “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Claims 21-22 are additionally and alternatively rejected under 35 U.S.C. 103 as being unpatentable over NPL Viitasaari in view of NPL Kim et al. as applied to Claims 9-16 and 20 above further in view of NPL Sun et al.
Regarding Claims 21-22, modified NPL Viitasaari teaches the limitations set forth above. NPL Viitasaari teaches a system for producing a gas feed containing bio-oil and/or fast pyrolysis biochar and feeding the stream as fuel to a blast furnace for iron ore reduction to produce metallic iron (Abstract) (Figs. 1, 9, Pages 7, 31).
NPL Viitasaari teaches the use of fast pyrolysis biochar e.g. at (Page 8) but does not expressly teach biochar produced by fast pyrolysis with a volatile matter content of at least about 20%.
However, NPL Sun et al. teaches exemplary biochars formed from fast pyrolysis having volatile matter contents of 24.1% and 83.46% (Figure 2., Page 6), both overlapping the instantly claimed ranges of about 20% and about 24%.
See MPEP 2144.05. In cases where claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to utilize a fast pyrolysis produced biochar having a volatile matter content of 24% or 83.46% in the system of NPL Viitasaari in order to improve production efficiency, based on the teachings of NPL Sun et al. at (Abstract, Pages 5-6), meeting the limitations of the instant Claim.
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Response to Arguments
Applicant's arguments filed 06/11/2026 have been fully considered but they are not persuasive.
Applicant argues the cited primary reference does not teach the claimed H/C ratio or volatile matter content claimed.
However, the claims are drawn to a system, and not to a method of producing biochar or a method of ironmaking or gasifying fuel. Therefore, the system of the prior art is capable of gasifying fast pyrolysis biochar and consequently reads on, or otherwise overlaps and encompasses the instantly claimed subject matter.
As set forth above, biochars produced via fast pyrolysis having volatile matter contents overlapping and lying within the instantly claimed ranges were known to persons of ordinary skill in the art at the time of filing the invention.
The system of NPL Viitasaari reads on the limitations of the instant claims. As established above, a material or article worked upon does not limit apparatus claims. See MPEP 2115. "Inclusion of the material or article worked upon by a structure being claimed does not impart patentability to the claims." In re Otto, 312 F.2d 937, 136 USPQ 458, 459 (CCPA 1963); see also In re Young, 75 F.2d 996, 25 USPQ 69 (CCPA 1935). In the instant case, the material acted upon (biofuel) is not required or critical for the function of the apparatus, the claimed system. Nonetheless, additionally and alternatively, the teachings of NPL Viitasaari in view of the cited prior art render the system of Claim 9 obvious to persons of ordinary skill in the art at the time of filing the invention.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
CN 116855267 A teaches producing biomass pyrolysis oil as clean fuel.
Leng, Lijian, and Huajun Huang. "An overview of the effect of pyrolysis process parameters on biochar stability." Bioresource technology 270 (2018): 627-642. teaches comprehensively how biochar performance is impacted by physical properties, reaction time, and processing temperature among other factors.
US 8945247 B1 teaches gasification reactors for carbonaceous biomass solid feedstocks.
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/M.S.S./Examiner, Art Unit 1733
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