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 .
Response to Amendment
The amendment filed 04/20/2026 has been entered. Claim(s) 1-19 is/are pending in this application and examined herein. Claim(s) 1,3 and 15-19 is/are withdrawn. Claim(s) 2, 6-9, and 11-14 is/are amended.
The objection(s) to claim(s) 6-9 and 11-14 is/are withdrawn in view of the amendments to claim(s) 6-9 and 11-14 respectively.
The rejection(s) under 35 USC 112(b) to claim(s) 2 and 4-14 is/are withdrawn in view of the amendments to claim(s) 2, 8, and 11.
Claim Objections
Claims 2 are objected to because of the following informalities:
Claim 2: “(a) iron ore, (b) gaseous oxygen and (c) a solid reductant” in line 3 should read “iron ore, gaseous oxygen, and solid reductant” to not be conflated with the process steps designated as (a), (b), and (c) disclosed later in claim 2.
Appropriate correction is required.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
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 2, 4-6, 9, and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Lindstrom (US 4360378 A, cited in IDS filed 11/21/2022) in view of Orth et al. (US 20080196549 A1, cited in IDS filed 11/21/2022).
Regarding claim 2, Lindstrom teaches a process for producing direct reduced iron (“DRI”) from iron-containing material and biofuel in a fluidized bed (Abstract, Col. 2 lines 31-42), wherein the iron-containing material may be iron ore concentrate (e.g., Col. 5 lines 3-7) and wherein the biofuel may be fuel wood, wood waste, straw, kelp, or peat (i.e., 100% biomass by weight) (Col. 3 line 67-Col. 4 line 11, claim 1). Lindstrom teaches the fluidized bed reactor comprising a single fluidized bed (Col. 2 lines 40-42, Col. 5 lines 34-52, Fig. 4). The instant application defines a “single stage” to mean “that gas and solids are brought into contact with one another in the fluidized bed in such a way that they are mixed together in and reside at (or close to) a single, common operating temperature” (instant specification: pg. 5 lines 20-22), however Lindstrom teaches that gas 3 and solids 6 are mixed together and reside in the fluidized bed reactor (Fig. 4, Col. 5 lines 34-52), and while the reactor operates at different temperatures at different stages (Fig. 1, claim 1), the steps may all occur in a single reactor, where the entire reactor is at the same temperature during each stage (Claims 1, 15, 7-8, Col. 6 lines 47-51), Lindstrom teaching a single stage fluidized bed as claimed. Lindstrom teaches feeding iron ore (Fig. 1), air and/or oxygen (i.e., gaseous oxygen) (Col. 5 lines 46-51, Col. 6 lines 27-29) and solid reductant including biomass into the fluidized bed (i.e., a reaction zone of the fluidized bed) (Fig. 1, Abstract, Col. 4 lines 11-22, Claims 4-5). Lindstrom teaches operating the fluidized bed so that the fluidized bed has an operating temperature such as 800 °C (Col. 2 line 66), which is within the claimed 750-850 °C range. Lindstrom teaches reducing iron ore and forming DRI in the fluidized bed (Abstract, Col. 2 lines 64-68), and discharging iron product (i.e., DRI) from the fluidized bed (Fig. 1).
Lindstrom does not teach the fluidized bed having a lower region, an intermediate region, or an upper region, pneumatically injecting the solid reductant into the lower region of the bed, or injecting oxygen via one or more downward-facing nozzles.
Orth teaches a direct reduction process for a metalliferous material includes supplying the metalliferous material such as ore (Abstract, [0001]), a solid carbonaceous material, an oxygen-containing gas, and a fluidizing gas into a fluidized bed in a vessel (Abstract), therefore Orth and Lindstrom are analogous to the instant application as both are directed to direct reduction of iron ore to direct reduced iron. Orth teaches the fluidized bed having a metal-rich zone (i.e., a lower region) which has a higher volumetric concentration of DRI relative to the rest of the bed (Fig. 1, [0006]), and an intermediate region which has a lower concentration of DRI and a higher concentration of char relative to the lower region (Fig. 1, [0007, 0038]). Orth teaches an upper region [0077], where as the upper region is neither metal or carbon rich [0006-0007], the upper region is relatively lean in both DRI and char relative to the lower region and the intermediate region. Orth teaches the solid feed materials (i.e., including solid reactant) are injected by a solids injection lance (i.e., pneumatically injecting the solid reductant) [0063], where at least some solids from the solid reductant reach the lower region of the bed [0072]. Orth teaches injecting oxygen via a downward-facing nozzle 5 extending into the fluidized bed above the lower region 19 (Fig. 1, [0024-0025, 0064]). Orth teaches the fluidized bed can accept metalliferous feed material with a particle size of less than 100 microns without this material exiting the process entrained in off-gas due to an agglomeration mechanism operating within the fluidized bed that promotes a desirable level of agglomeration between particles of feed materials [0037].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a fluidized bed as taught by Orth as the fluidized bed of Lindstrom as doing so would allow use of metalliferous feed material with a particle size of less than 100 microns without negative effects as taught by Orth.
Claim(s) 4-6, 9, and 14 remain(s) rejected as set forth in the Office Action dated 11/18/2025. Claim(s) 4-5 has/have not been amended since that time, and the amendments to claim(s) 6, 9, and 14 are of an editorial nature and do not materially affect any statements made in the rejection in the prior Office Action. Therefore, the previously presented grounds of rejection set forth how the prior art teaches or suggests all of the limitations of the claim(s).
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Lindstrom in view of Orth as applied to claim 2 above, and further in view of Berg (US 20090000144 A1, cited in Office Action dated 11/18/2025).
Claim(s) 7 remain(s) rejected as set forth in the Office Action dated 11/18/2025. The amendments to claim(s) 7 are of an editorial nature and do not materially affect any statements made in the rejection in the prior Office Action. Therefore, the previously presented grounds of rejection set forth how the prior art teaches or suggests all of the limitations of the claim(s).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Lindstrom in view of Orth as applied to claim 2 above, and further in view of Maki et al. (US 4758117 A, cited in Office Action dated 11/18/2025).
Claim(s) 8 remain(s) rejected as set forth in the Office Action dated 11/18/2025. The amendments to claim(s) 8 are of an editorial nature and do not materially affect any statements made in the rejection in the prior Office Action. Therefore, the previously presented grounds of rejection set forth how the prior art teaches or suggests all of the limitations of the claim(s).
Claims 10-11 are rejected under 35 U.S.C. 103 as being unpatentable over Lindstrom in view of Orth as applied to claim 2 above, and further in view of Lee et al. (US 5762681 A, cited in Office Action dated 11/18/2025).
Claim(s) 10-11 remain(s) rejected as set forth in the Office Action dated 11/18/2025. Claim(s) 10 has/have not been amended since that time, and the amendments to claim(s) 11 are of an editorial nature and do not materially affect any statements made in the rejection in the prior Office Action. Therefore, the previously presented grounds of rejection set forth how the prior art teaches or suggests all of the limitations of the claim(s).
Claims 12-13 are rejected under 35 U.S.C. 103 as being unpatentable over Lindstrom in view of Orth as applied to claim 2 above, and further in view of Marsh et al. (US 20090324440 A1, cited in IDS filed 11/21/2022).
Claim(s) 12-13 remain(s) rejected as set forth in the Office Action dated 11/18/2025. The amendments to claim(s) 12-13 are of an editorial nature and do not materially affect any statements made in the rejection in the prior Office Action. Therefore, the previously presented grounds of rejection set forth how the prior art teaches or suggests all of the limitations of the claim(s).
Response to Arguments
Applicant's arguments filed 04/20/2026 have been fully considered but they are not persuasive.
Regarding Applicant’s argument that Lindstrom and Orth are not properly combinable because Lindstrom is directed to a biomass-specific reduction system, while Orth teaches a process tailored to coal-based thermochemical behavior (see pg. 7-10 of remarks), the Examiner respectfully disagrees.
While as Applicant notes, Lindstrom discloses biomass to have different properties compared to fossil fuels, Lindstrom the properties constituting the foundation of the Lindstrom’s process to be that biomass and peat can undergo very rapid heating under flash pyrolysis, and that they experience high reactivity during a gasification step (Lindstrom: Col. 4 lines 23-36). Lindstrom then attributes these properties as responsible for reduction occurring at the relatively lower temperatures of the process of Lindstrom compared to others (Lindstrom: Col. 5 lines 13-16). Lindstrom does not however, disclose any specific features to be necessary or present in the construction of the fluidized bed reactor used based on such properties or behavior, instead Lindstrom discloses that the method may be carried out in different kinds of fluidized bed reactors in different system configurations (Lindstrom: Abstract), such as classical fluidized beds, or other reactor types such as circulating fluidized beds (Lindstrom: Col. 6 line 63 – Col. 7 line 5). Therefore, Lindstrom appears to instead suggest that while the certain properties of biomass differ greatly from e.g., coal, the resulting differences in behavior of the biomass or peat in a direct reduction process are largely if not entirely accounted for by the lower temperatures used in the process, and do not e.g., limit or restrict the choices of fluidized bed or prohibit zonal injection and oxygen management; and that the process may be performed with a variety of different constructions of fluidized bed reactor, thus the fluidized bed reactor of Orth could presumably be used with a reasonable expectation of success.
While as Applicant notes, Orth is directed to a process that preferably uses coal (e.g., Orth: [0038]), Orth explicitly discloses that the process (and in turn the equipment used to carry out such a process) is not limited to coal, but extends to the use of any other suitable solid carbonaceous material (Orth: [0061]). As Lindstrom teaches biomass to be a suitable solid carbonaceous material for performing direct reduction of iron in a fluidized bed reactor, using biomass in the fluidized bed reactor of Orth would have a reasonable expectation of success, and without resulting in “altering the very basis on which Lindstrom operates” as Applicant suggests.
Further, Lindstrom in view of Orth as applied in the rejection of claim 2 does not change the principle of operation of Lindstrom: other types of fluidized bed reactor beyond that shown in Lindstrom are permitted within the invention of Lindstrom, and Orth would have been amenable to using biomass in its fluidized bed reactor, thus the principle of operation of Lindstrom (direct reduction of iron in a fluidized bed reactor using biomass at the claimed temperatures of Lindstrom) is unchanged.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning (see pg. 10 of remarks), it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). As in the instant case, the combination of Lindstrom and Orth is based on the expected advantage of allowing use of metalliferous feed material with a particle size of less than 100 microns without negative effects as taught by Orth, the reconstruction is proper.
Regarding Applicant’s argument that Lindstrom in view of Orth does not teach a “single stage” as claimed and as defined by the instant specification (see pg. 11-13 of remarks), the Examiner respectfully disagrees.
As Applicant notes, the instant specification defines “single stage” to mean “that gas and solids are brought into contact with one another in the fluidized bed in such a way that they are mixed together in and reside at (or close to) a single, common operating temperature” (instant specification: pg. 5 lines 20-22). Therefore, Applicant’s definition requires that:
Gas and solids are brought into contact with one another in the fluidized bed,
that the gas and solids are mixed together in the fluidized bed reactor, and
that the gas and solids reside at or close to a single common operating temperature
None of the limitations imposed by this definition, nor the context in which “single stage” is used in claim 2, however, require that the “single stage” actually comprise a single process step.
While it has long been established that Applicant may be their own lexicographer, Applicant cannot act as their own lexicographer and require that claim terminology be given its plain meaning, instead acting as one’s own lexicographer to define the meaning of a term is an exception to giving the worlds in a claim their ordinary and customary meaning, and where an explicit definition is provided by the applicant for a term, that definition will control interpretation of the claim. See MPEP 2111.01 (IV).
Therefore, as Lindstrom teaches bringing gas and solids into contact with one another in the fluidized bed and are mixed together in the fluidized bed reactor (Lindstrom: Fig. 4, Col. 5 lines 34-52), and that they reside at or close to a single common operating temperature during each step in the reactor (Claims 1, 7-8, 15, Col. 6 lines 47-51), Lindstrom teaches all of the features of a “single stage reactor” as claimed and as defined in the instant application, even if Lindstrom discloses that the process may operate in a batch-wise manner or in multiple steps as understood by the plain meaning of a process “step”.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Nikolas T Pullen whose telephone number is (571)272-1995. The examiner can normally be reached Monday - Thursday: 10:00 AM - 6:00 PM EST.
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/NIKOLAS TAKUYA PULLEN/Examiner, Art Unit 1733
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