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 § 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 7-15 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.
Claim 7 recites the limitation "the granulated slag" in line 4. There is insufficient antecedent basis for this limitation in the claim.
Claim 13 recites a percentage without a basis, e.g. mass, volume, or mole. The lack of a basis makes the limitation unclear. Correction is required, though new matter will be subject to analysis under 35 U.S.C. 112, first paragraph.
Claim 14 recites a percentage without a basis, e.g. mass, volume, or mole. The lack of a basis makes the limitation unclear. Correction is required, though new matter will be subject to analysis under 35 U.S.C. 112, first paragraph.
Claim 15 recites a percentage without a basis, e.g. mass, volume, or mole. The lack of a basis makes the limitation unclear. Correction is required, though new matter will be subject to analysis under 35 U.S.C. 112, first paragraph.
Claims dependent on any of the rejected claims are likewise rejected under this statute.
Claim Rejections - 35 USC § 102
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-3 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Greenwalt (US 5,397,376) and as evidenced by Hasanbeigi et al in Renewable and Sustainable Energy Reviews.
Greenwalt as evidenced by Hasanbeigi et al in Renewable and Sustainable Energy Reviews is applied as discussed in the office action mailed 01/16/2026.
Claims 1-3 and 13-15 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Schlüter et al (US 2023/0175087 A1), which is in the same patent family as CA 3181620 A1 published 11/04/2021.
Applicant cannot rely upon the certified copy of the foreign priority application to overcome this rejection because a translation of said application has not been made of record in accordance with 37 CFR 1.55. When an English language translation of a non-English language foreign application is required, the translation must be that of the certified copy (of the foreign application as filed) submitted together with a statement that the translation of the certified copy is accurate. See MPEP §§ 215 and 216.
Schlüter et al is applied as discussed in the office action mailed 01/16/2026 for Claims 1-3.
Regarding Claim 13, the furnace is electrically operated [0013].
Regarding Claim 14, the iron content in the granulated slag is less than 1.0 wt. % [0075].
Regarding Claim 15, the iron content in the granulated slag is less than 1.0 wt. % [0075].
Claim 1 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by EP 0134852 A1.
EP 0134852 A1 (EP ‘852) teaches producing liquid iron in an electric melter or furnace as represented below in the drawing:
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The molten iron is pig iron (page 26, line 6). The direct reduction plant is represented above and also on page 6, lines 5 and 6. Slag is produced in the iron melter as represented above. Samples of slag or liquid iron can be taken at any time. If it is desired to increase a carbon rate, excess or additional carbon can be entered in a controlled matter. If it is desired to increase oxygen levels within the melter, additional ore or oxygen can be entered in a controlled manner (page 23, lines 3-9). Electrical parameters also permit control of reduction within the slag to provide the liquid iron with required levels of dissolved oxides (page 24, lines 23-27). Controlled feed of carbon is an important control parameter to maintain correct slag chemistry (page 28, lines 13-16). Therefore, EP ‘852 teaches step a) heating iron oxide in a direct reduction plant where a majority of the iron oxide is reduced (page 7, lines 1-5); step b) heating to give pig iron and slag (see at least drawing above); step c) analyzing the iron-containing intermediate and/or slag (page 23, lines 3 and 4); and d1) determining a property of an additive to alter the composition of the slag (page 28, lines 13-16) or d2) controlling electrical parameters for the temperatures of the slag and iron and control of reduction in the slag (page 24, lines 17-27). EP ‘852 anticipates the claimed invention.
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.
Claims 4-8 are rejected under 35 U.S.C. 103 as being unpatentable over Schlüter et al as applied to claims 1-3 above, and further in view of WO 2020/245070 A1.
Schlüter et al further in view of WO 2020/245070 A1 is applied as discussed in the office action mailed 01/16/2026.
Claims 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over Schlüter et al in view of WO ‘070 as applied to claims 1-9 above, and further in view of DE 10340880 A1, based on the original document and machine translation.
Schlüter et al further in view of WO 2020/245070 A1 and DE 10340880 A1 is applied as discussed in the office action mailed 01/16/2026.
Claims 2-8 and 13-15 are rejected under 35 U.S.C. 103 as being unpatentable over EP ‘852 as applied to claim 1 above, and further in view of Golberger et al (US 2011/0247457 A1).
EP ‘852 discloses the invention substantially as claimed. However, EP ‘852 does not teach direct reduction comprises hydrogen as a reducing agent as claimed.
Golberger et al teaches direct reduction (DRI) of iron oxides from pellets composed of iron oxide and carbonaceous material (abstract). The carbonaceous material includes coal [0025]. Solid particles are fluidized with a gas including hydrogen; the presence of a gaseous reductant in the fluidizing gas increases the rate of DRI pellet reduction [0040]. Sponge iron and DRI are analogous. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use the reduction process of Golberger et al in the process of EP ‘852, since Golberger et al teaches higher reduction and production rates [0016].
Regarding Claim 3, EP ‘852 teaches the melter has a reducing atmosphere (page 24, lines 23-25).
Regarding Claim 4, Golberger et al teaches reduction occurs between 850-1100 °C (abstract), which overlaps the claimed range.
Regarding Claim 5, EP ‘852 teaches determining the composition of the metal and slag and a “desired target composition” (“GOOD OPERATION,” page 30). It is desirable to maintain the slag between 2-4% Fe (page 28, lines 20-22).
Regarding Claim 6, EP ‘852 teaches a controlled feed of carbon (page 28, line 14) based on the amount of carbon that is contained in char(page 26, lines 1-3), which reads on a control unit being present.
Regarding Claim 7, EP ‘852 the control of reduction within the slag to provide the liquid iron with required levels of dissolved oxides (page 24, lines 23-27) reads on a desired chemical composition of the slag.
Regarding Claim 8, EP ‘852 teaches an opening for introducing raw material as represented in 11 in FIG. 2. The control occurs after the introduction of material, since samples of the slag or liquid iron can be taken at any time (page 23, lines 3 and 4).
Regarding Claim 13, EP ‘852 teaches the smelter is an electric furnace (page 1, line 3).
Regarding Claim 14, EP ‘852 teaches 2-3% and 3-6% FeO in the slag (page 31).
Regarding Claim 15, EP ‘852 teaches 2-3% and 3-6% FeO in the slag (page 31), which partially overlaps the claimed range.
In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists because the prior art discloses the utility of the composition over the entire disclosed range. See MPEP § 2144.05.
Claim 9 is rejected over EP ‘852 in view of Golberger et al as applied to claims 1-8 above, and further in view of Saleh et al in Indonesian Mining Journal.
EP ‘852 in view of Golberger et al discloses the invention substantially as claimed. However, EP ‘852 in view of Golberger et al does not teach the slag basicity as in Claim 9.
Saleh et al teaches a study on basicity in direct reduced iron smelting, where the iron smelting produces pig iron and slag (abstract). The best conditions were at a basicity of 1.1 8 (page 68). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention for the slag basicity in EP ‘852 in view of Golberger et al to be 1.18 as taught by Saleh et al, since Saleh et al teaches high iron content (page 64).
Claims 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over EP ‘852 in view of Golberger et al and Sahel et al as applied to claims 1-9 above, and further in view of DE ‘880 A1.
EP ‘852 in view of Golberger et al and Sahel et al discloses the invention substantially as claimed. Regarding Claim 10, EP ‘852 teaches the electric furnace as the first reactor. However, EP ‘852 in view of Golberger et al and Sahel et al does not teach a second reactor configured to receive the slag as claimed.
DE ‘880 teaches pulverizing pig iron slag from a blast furnace (page 1) as represented in the drawing below:
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DE ‘880 teaches before atomizing the slag, an additive is added to the slag after separation from pig iron. The additive is added with means 9 and 10 (page 3), which reads on having a control unit. An additive is added to the slag to increase or decrease the basicity to 1 to 5.5 (page 3).The second reactor is taught by tundish 7 and atomizer 8. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use the slag treatment system of DE ‘880 to treat the slag in the process taught by EP ‘852 in view of Golberger et al and Sahel et al, since DE ’880 teaches facilitating the process of atomizing slag to make higher quality binder (page 2).
Regarding Claim 11, DE ‘880 teaches the particle size is 1 to 100 microns (page 3), and atomizing occurs in 8.
Regarding Claim 12, DE ‘880 teaches mixing the ground slag with cement in a ratio of 36:64 to 95:5 to form a binder whose 28-d standard strength is at least 30 N/mm2 (page 3).
Response to Arguments
Applicant's arguments filed 04/16/2026 have been fully considered but they are not persuasive. Applicant argues Greenwalt does not disclose analyzing the iron-containing intermediate and/or the slag that deposits during the heating of the iron-containing intermediate. Greenwalt teaches “analyzing, via an analysis unit, … the slag” as recited in Claim 1, line 8 by evaluating the sulfur content of the slag by evaluating the ratio of oxygen partial pressure to sulfur partial pressure by derivation (column 11, lines 34-54). Greenwalt teaches “recognizing the slag requires a thermal treatment to give the slag the desired characteristics, and initiating the thermal treatment” by controlling the melter gasifier dome temperature with CO2 (column 17, lines 42-44) and thus the sulfur capacity function (column 11, lines 37-39). The claim does not suggest an analytical feedback step for the d2) option.
Applicant argues Schlüter et al does not expressly disclose step c) “as a distinct analytical step separate from the process model computation.” Schlüter et al teaches adjusting the slag phase [0015] with automated addition ensuring the necessary adjustments of the desired metal and/or slag parameters [0025]. Therefore, Schlüter et al teaches an analytical 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 Tima M. McGuthry-Banks whose telephone number is (571)272-2744. The examiner can normally be reached Monday through Friday, 7:30 am to 4:00 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith D. Hendricks can be reached at (571) 272-1401. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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Tima M. McGuthry-Banks
Primary Examiner
Art Unit 1733
/TIMA M. MCGUTHRY-BANKS/Primary Examiner, Art Unit 1733
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