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 Arguments
Applicant’s arguments, see Page 9, lines 1-5 of Remarks, filed July 7th, 2026, with respect to the rejection of claims 3, 7, and 20 under 35 U.S.C. 112(b)/2nd Paragraph have been fully considered and are persuasive. Due to amendments to the claims, the rejections have been withdrawn.
Applicant’s arguments, see Page 9, line 6 - Page 14, line 21 of Remarks, filed July 7th, 2026, with respect to the rejections of claims 1-8, 10-11, 14, 18-19, and 21-24 under 35 U.S.C. 102(a)(1) and of claims 12-13, 15-17, and 20 under 35 U.S.C. 103 have been fully considered and are persuasive. Due to amendments to the independent claim 1, the rejections have been withdrawn. However, upon further consideration, new grounds of rejection are made in view of the prior art over the amended claims.
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 1-6, 8-12, 18, 21-22, and 24 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Robin (WO 2023/166464 A1, effectively filed 02 March 2022, corresponding to the filing date of provisional U.S. Application 63/315,632).
Regarding claim 1, Robin teaches a process for producing metal oxide in a flash calciner (Robin, Figs. 6-7, [0021]-[0022], [0048], [0102]), the process comprising:
pre-heating a metal carbonate particulate stream, prior to the particulate stream being fed into the flash calciner (Robin, Figs. 6, [0021], pre-heating section 42); and,
calcining the particulate stream in a flash calciner to produce a raw stream comprising metal oxide (Robin, Fig. 6, [0021], decarbonated particles (16) comprising CaO and/or MgO) and a flue gas comprising CO2 (Robin, Fig. 6, [0021], flue gas recirculation; [0029], first entraining gas (4) contains carbon dioxide),
wherein at least a portion of the flue gas comprising CO2 produced in step (b) is used to pre-heat the metal carbonate particulate in step (a) (Robin, Fig. 6, [0021], “delivering at least some of the first entraining gas (4) to the reactor (8) from a location downstream of a solid/gas heat exchanger (44) in the pre-heating section (42) of the first circuit (2)”); and
wherein at least a portion of the flue gas comprising CO2 produced in step (b) is recycled back into the flash calciner via a furnace (Robin, Fig. 6, [0048], recycling passage 90 directs first entraining gas 4 (flue gas) through hot gas generator 70 (furnace)),
wherein the flue gas comprising CO2 is recirculated at above atmospheric pressure within the flash calciner (Robin, Fig. 7, [0022], “maintaining the current operating pressure in the reactor (8) at or above a neutral pressure with respect to said ambient air”) using a fan in a forced draft configuration (Robin, [0022] at Page 17, lines 4-8).
Regarding claim 2, Robin teaches the process according to claim 1, as discussed above, wherein step (a) is carried out by feeding the particulate stream and a portion of the flue gas stream comprising CO2 into a cyclonic heat exchanger system in a counter flow arrangement (Robin, Fig. 6, [0021], pre-heating section 42; [004141], pre-heaters are in a counter current gas-solid contact mode).
Regarding claim 3, Robin teaches the process according to claim 2, as discussed above, wherein the cyclonic heat exchanger system comprises a plurality of series connected cyclonic heat exchangers (Robin, Fig. 6, pre-heating section 42 comprises a plurality of series connected cyclonic heat exchangers).
Regarding claim 4, Robin teaches the process according to claim 1, as discussed above, comprising a step of separating a portion of the raw stream, after it exits the flash calciner, into a metal oxide stream and a flue gas stream which comprises CO2 (Robin, Figs. 2 and 6, [0021], decarbonated particles transferred to cooling section (22); flue gas (first entraining gas (4)) delivered to pre-heating section (42); [0029], first entraining gas (4) comprises carbon dioxide; [0043], second reactor 86 serves as a vessel for collecting the decarbonated particles 16 transferred from the reactor 8).
Regarding claim 5, Robin teaches the process according to claim 4, as discussed above, wherein the separation of the portion of the raw stream is carried out by a cyclone separator (Robin, Fig. 7, [0022] at Page 19, lines 7-9).
Regarding claim 6, Robin teaches the process according to claim 1, as discussed above, wherein the furnace heats the flue gas comprising CO2 to a temperature capable of maintaining auto-ignition of a fuel within the flash calciner (Robin, Fig. 7, [0021], “maintaining a ratio of oxygen provided to the hot gas generator (70): first entraining gas (4) which is sufficient for burning the first entraining gas (4) in the reactor (8)”; since auto-ignition is maintained, the temperature is capable of doing so).
Regarding claim 8, Robin teaches the process according to claim 4, as discussed above comprising a step of feeding a portion of the metal oxide from the separator to a cooler (Robin, Fig. 6, [0021] at Page 16, lines 9-11, “transferring the decarbonated particles (16) to a cooling section (22) of a second circuit (12) comprising a second entraining gas (14) in which the conveyed decarbonated particles (16) release a portion of their thermal energy”).
Regarding claim 9, Robin teaches the process according to claim 8, as discussed above, wherein the cooler is controlled to exclude CO2 (Robin, [0032] at Page 32, lines 21-23, “The cooling section (22) may comprise a second entraining gas (14) substantially free of carbon dioxide circulating within the cooling section (22).
Regarding claim 10, Robin teaches the process according to claim 1, as discussed above, comprising a step of feeding an admixture of fuel and oxidant into the flash calciner (Robin, [0018]).
Regarding claim 11, Robin teaches the process according to claim 1, as discussed above, comprising a step of feeding an admixture of fuel and oxidant into the furnace (Robin, [0023], natural gas and/or air to second reactor (86)).
Regarding claim 12, Robin teaches the process according to claim 10, as discussed above, wherein the fuel comprises a gaseous hydrocarbon and the oxidant comprises oxygen (Robin, [0014] at Page 9, lines 1-4).
Regarding claim 18, Robin teaches a process for calcining a metal carbonate feedstock within a flash calciner to produce a metal oxide and flue gas comprising CO2 (Robin, Figs. 6-7, [0021]-[0022], [0048], wherein the process comprises recirculating at least a portion of the flue gas comprising CO2 (Robin, Fig. 6, [0021], flue gas recirculation; [0029], first entraining gas (4) contains carbon dioxide) at a pressure above atmospheric pressure (Robin, Fig. 7, [0022], “maintaining the current operating pressure in the reactor (8) at or above a neutral pressure with respect to said ambient air”) within a closed loop fluid path (Robin, Fig. 6, annotated below) which includes a the flash calciner using a fan in a forced draft configuration (Robin, [0022] at Page 17, lines 4-8).
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551
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Figure 1. Fig. 6 of Robin showing loop fluid path of flue gas in instant claims 18 and 21.
Regarding claim 21, Robin teaches a process for calcining a metal carbonate feedstock within a flash calciner to produce a raw stream comprising metal oxide and a flue gas comprising CO2 (Robin, Figs. 6-7, [0021]-[0022], [0048], [0102]), wherein the process comprises recirculating and feeding a portion of the flue gas comprising CO2 (Robin, Fig. 6, [0021], flue gas recirculation; [0029], first entraining gas (4) contains carbon dioxide) back into the glash calciner via a fluid path which includes a preheater furnace (Robin, Fig. 6, [0048], recycling passage 90 directs first entraining gas 4 (flue gas) through hot gas generator 70 (furnace)) which heats the flue gas comprising CO2 to a temperature capable of maintaining auto-ignition of a fuel within the flash calciner (Robin, Fig. 7, [0021], “maintaining a ratio of oxygen provided to the hot gas generator (70): first entraining gas (4) which is sufficient for burning the first entraining gas (4) in the reactor (8)”; since auto-ignition is maintained, the temperature is capable of doing so),
wherein the flue gas comprising CO2 is recirculated at above atmospheric pressure within the fluid path (Robin, Fig. 6, annotated above) using a fan in a forced draft configuration (Robin, [0022] at Page 17, lines 4-8).
Regarding claim 22, Robin teaches the process according to claim 21, as discussed above, in which the temperature is between approximately 1100 and 1300°C (Robin, [0018] at Page 11, lines 14-15, temperature is within this range in the reactor and brought to this temperature range in the hot gas generator 70 - see Paragraph [0021]).
Regarding claim 24, Robin teaches the process according to claim 21, as discussed above, wherein the recirculated flue gas comprising CO2 is used to carry a fluidized stream of metal carbonate feedstock through one or more counter flow cyclonic heating stages (Robin, Fig. 6, [0021], pre-heating section 42; [004141], pre-heaters are in a counter current gas-solid contact mode), such that the metal carbonate feedstock is thereby heated by the flue gas comprising CO2 prior to being fed into the flash calciner (Robin, Fig. 6, [0021] at Page 16, lines 4-6, “conveying particles of carbonated materials (6) by a first entraining gas (4) in the first circuit (2) for preheating said carbonated materials (6), said entraining gas (4) comprising said carbon dioxide”).
Claims 13 is rejected under 35 U.S.C. 102(a)(2) as being anticipated by Robin (WO 2023/166464 A1, effectively filed 02 March 2022, corresponding to the filing date of provisional U.S. Application 63/315,632), as applied to claim 12 above, further evidenced by OSSM (“Gas mixtures - Amagat’s law of partial volumes”, 2024), and further evidenced by Randall (“Composition of Air”, 2019)
Regarding claim 13, Robin teaches the process according to claim 12, as discussed above, wherein the oxygen enriched air comprises greater than 90% by volume oxygen (Robin, [0048], [0101]). While the range of greater than 90% by volume oxygen is not explicitly at least 50% by weight oxygen, the following demonstrates that this is necessarily the case: For a gas mixture which is 90% by volume oxygen to be less than 50% by weight oxygen, the average molecular weight of the non-oxygen gas in the mixture would need to be over 9 times the molecular weight of oxygen. This follows from Amagat’s law of partial volumes, namely that the volume of a mixture can be expressed as a sum of partial volumes of its component species, each of which is proportional to its molar amount within its respective partial volume (see “Gas Mixtures”, Page 1). In a sample of 1 mol of gas having a composition at the lower bound of Robin’s range of greater than 90% by volume O2,
0.9
m
o
l
O
2
32
g
O
2
m
o
l
O
2
=
28.8
g
O
2
0.1
m
o
l
n
o
n
O
2
x
g
n
o
n
O
2
m
o
l
n
o
n
O
2
=
28.8
g
n
o
n
O
2
x
=
288
g
/
m
o
l
Thus, in an ideal gaseous mixture having an equal mass of O2 and non-O2 components where O2 makes up 90% of the volume, the non-O2 components would have an average molecular weight of 288 g/mol. Correspondingly, the average molar mass of non-O2 components would have to be greater than 288 g/mol for there to be less than 50% by weight oxygen. Air has no components that are greater than 288 g/mol, much less an average molecular weight of greater than 288 g/mol (see Randall, Table 1), so Robin’s range of greater than 90% O2 by volume anticipates the claimed range of enriched air comprising at least 50% by weight oxygen.
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 7 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Robin (WO 2023/166464 A1), as applied respectively to claims 1 and 18 above.
Regarding claim 7, Robin teaches the process according to claim 1, as discussed above, wherein the furnace heats the recycled flue gas stream to a temperature of between approximately 1100 and 1300°C (Robin, [0018] at Page 11, lines 14-15, temperature is within this range in the reactor (flash calciner) and brought to this temperature range in the hot gas generator 70 (furnace) - see Paragraph [0021]), which overlaps with the claimed range of from 500°C to 1200°C.
It would have been obvious to one of ordinary skill in the art before the
effective filing date of the invention to have selected the overlapping portion of the
temperature ranges because selection of overlapping portions of ranges has been held to be a prima facie case of obviousness. See MPEP § 2144.05.I.
Regarding claim 20, Robin teaches the process according to claim 18, as discussed above, wherein the flue gas comprising CO2 is heated within a preheater furnace by combustion of a fuel/oxygen mixture (Robin, [0028] at Page 27, lines 16-21) to a temperature of between approximately 1100 and 1300°C (Robin, [0018] at Page 11, lines 14-15, temperature is within this range in the reactor (flash calciner) and brought to this temperature range in the hot gas generator 70 (furnace) - see Paragraph [0021]), which overlaps with the claimed range of from 500°C to 1200°C.
It would have been obvious to one of ordinary skill in the art before the
effective filing date of the invention to have selected the overlapping portion of the
temperature ranges because selection of overlapping portions of ranges has been held to be a prima facie case of obviousness. See MPEP § 2144.05.I.
Claims 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Robin (WO 2023/166464 A1), as applied to claim 1 above, and further in view of Jia (CN 112344742 A) (the machine translation of record is referenced below).
Regarding claim 15, Robin teaches the process according to claim 1, as discussed above, wherein a portion of the flue gas stream comprising CO2 passes through a purification and storage process, wherein this step occurs after the portion of the flue gas stream is used to pre-heat the metal carbonate particulate stream (Robin, Fig. 1, [0036], “This facilitates the final purification of the exhaust gas 4 into a suitable purity for downstream CO2 use or sequestration.”). Robin does not explicitly teach that part of this purification and storage process comprises CO2 passing through a condensing heat exchanger. However, in an analogous process of separating and storing CO2 from flue gas, Jia teaches using a condensing heat exchanger to cool CO2 in the flue gas for storage (Jia, [0062]).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to have modified Robin’s method by incorporating passing CO2 through a condensing heat exchanger as taught by Jia (Jia, [0062]). The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art (see MPEP 2143.A.). The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, USPQ2d 1385, 1395 - 97 (2007) (see MPEP § 2143.B.). In the instant case, incorporating a condensing heat exchanger would yield the predictable result of preparing the CO2 in a form that can be sequestered after it is used to preheat the reactants, which is a stated goal of Robin (Robin, [0009], [0036]).
Regarding claim 16, modified Robin renders the process according to claim 15 obvious, as discussed above, comprising a step of separating and sequestering a portion of the CO2 in the flue gas stream that has passed through the condensing heat exchanger (Robin, [0009], [0036]; Jia, [0062]; see discussion of claim 15 above).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over Robin (WO 2023/166464 A1), as applied to claim 1 above, and further in view of Bittner (U.S. 2020/0361819 A1).
Regarding claim 17, Robin teaches the process according to claim 1, as discussed above, wherein the metal carbonate particulate stream comprises CaCO3 particles (Robin, [0036], limestone, [0037], [0097], CaCO3). Robin does not explicitly teach that the CaCO3 particles have an average particle size of 5 to 120 μm. However, Bittner teaches that CaCO3 particles having a particle size of 50 μm to 5 mm, which overlaps with the claimed range of 5 to 120 μm, are suitable for a similar lime production process (Bittner, [0032]).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to have selected a CaCO3 particle size of 50 μm to 5mm in Robin’s process. The selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960), Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945), and MPEP § 2144.07. In the instant case, it was known that a CaCO3 particle size of 50 μm to 5 mm was suitable for lime production (Bittner, [0020]).
Additionally, it would have been obvious to one of ordinary skill in the art before the
effective filing date of the invention to have selected the overlapping portion of the particle sizes because selection of overlapping portions of ranges has been held to be a prima facie case of obviousness. See MPEP § 2144.05.I.
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 ZACHARY J. BAUM whose telephone number is (571)270-0895. The examiner can normally be reached Monday-Friday 8:30-5:00.
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/ZACHARY JOHN BAUM/Examiner, Art Unit 1736
/ANTHONY J ZIMMER/Supervisory Patent Examiner, Art Unit 1736
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