Detailed Office Action
Notice of Pre-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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Restriction/Election
Applicant’s election without traverse of Group II, claims 13 – 23 in the reply filed on 07/14/26 is acknowledged. Claims 1 – 12 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Group I, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 07/14/26.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
In particular, the limitation of claim 1 of “means therein for reducing the pressure of said portion of gas” because the limitation/claim recites the word “means”, the “means” is modified with functional language, and the claim does not recite structure for accomplishing the function. [Page 6, line 16 – 26] describes that the means can be a turbine, vent vale, or expansion value.
Claim Rejections – U.S.C. § 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.
Claim 18 is 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.
Regarding claim 18, “the system according to any claim 17” is indefinite. The use of “any” makes it unclear whether all of claim 17 is incorporated into claim 18 or only part of claim 17 is. The former interpretation is taken for purposes of examination.
Claim Rejections – U.S.C. §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 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.
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.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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 13 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over Millner (US2015/0007697) in view of Bechara (NPL, 2018) alone, or additionally in view of Michigan (“Pressure Relief and Control”; 2017)
Regarding claim 13, Millner teaches a system for iron-oxide reduction [Title]. The system contains a reduction unit [Fig. “1”] connected to a gas line “7” to introduce gas and a gas exit “3”, meeting the limitations of a reduction unit with a second inlet and outlet for reduction gas and top gas.
The system contains a feed gas line “4” connected to the gas line “7” [Figure]. The top gas is recycled “15” with a first circuit “8” connecting to the gas line “7” downstream of a compressor “5”. Meeting the claimed limitation of a primary circuit for conducting part of the top gas from the outlet to the gas line downstream of a compressor.
The system also contains a second circuit “8”” which contains a compressor “12” and connects to the gas line “7” upstream from the compressor “5”, meeting the claimed limitation of a secondary circuit for conducting part of the top gas removed from the primary circuit to another part of the gas line with is upstream from the first compressor.
Millner teaches that this circuit has a valve “9” that regulates the amount of gas that the enters the circuit [Figure; 0059], meeting the claimed limitation of a first valve for controlling flow into the secondary circuit. Millner states that the valve is controlled/regulated such that the flow size is increased and the recycle gas is mixed into the feed gas line when the pressure of the recycle gas lies above the pressure the feed gas [0028]. That is, the valves disclosed in Millner open in response to the upstream pressure (e.g. for the primary circuit/secondary circuit) being higher than a threshold (e.g. the feed gas line pressure, meeting the claimed limitation of the valve configured to open in response to the pressure being above a threshold.
Millner teaches that the reduction unit can be a shaft [0025] but does not expressly disclose an inlet and outlet for iron ore and sponge iron, respectively.
Bechara provides a schematic diagram for a reduction shaft furnace that is used for iron ore [Title, Figure 2]. As shown in Figure 2, the reduction shaft furnace contains an inlet for pellets and outlet for directly reduced iron, in addition to an inlet and outlet for gas (including top gas).
It would have been obvious to one of ordinary skill in the art before the effective filing date to have included an inlet and outlet for iron material in the shaft reduction unit disclosed by Millner, as disclosed by Bechara, to achieve predictable results. Both are directed to the same field of endeavor of iron reduction. Additionally, Millner teaches that the reduction unit can be a shaft reduction furnace and as such, an ordinarily skilled artisan would have had a reasonable expectation of success in combining the teachings to achieve predictable results with no changes in their respective functions.
Millner teaches that the circuit (“8”” interpreted as the secondary line) also has another section which can draw from the secondary circuit to account for fluctuations in feed gas pressure [0061]. Wherein this meets the broadest reasonable interpretation of a means for reducing pressure of gas in the secondary circuit (i.e., via diverting gas volume from the secondary circuit).
Alternatively, Michigan provides an overview of process control in process engineering [Title]. Michigan discloses that pressure control in a system is critical for safety and that equipment such as sensor, controller, and valves are used to monitor and maintain pressure and process safety [Page 1]. In particular, Michigan teaches that pressure relief equipment such as pressure relief valves must be included in any system which generates high pressure [page 5].
As such, it would have been obvious to one of ordinary skill in the art before the effective filing date to have included pressure relief valves within each of the gas lines of Millner in order to promote process safety, as described by Michigan (meeting the claimed limitation of a pressure reducing device in the secondary circuit). Millner is directed to a process in which gas pressures of 10 Bar or higher are generated and as such, an ordinarily skilled artisan would have considered the teachings of pressure control and safety of Michigan to be pertinent to the system of Millner and would have had a reasonable expectation of the success in implementing them.
Regarding claim 21, Millner in view of Bechara alone, or in view of Michigan teaches the invention as applied in claim 13. Millner teaches that the recycle loop (“15”) can comprise a heat exchanger [0039, “14”], meeting the claimed limitation.
Claims 17 – 18 are rejected under 35 U.S.C. 103 as being unpatentable over Millner (US2015/0007697) in view of Bechara (NPL, 2018) alone, or additionally in view of Michigan (“Pressure Relief and Control”; 2017)
Regarding claims 17 – 18, Millner in view of Bechara alone, or in further view of Michigan teaches the invention as applied in claim 13. Millner teaches that the primary circuit has a compressor downstream of a point where the secondary circuit is connected to the primary circuit [Figure], meeting the claimed limitation of claim 18.
Millner states that the valve is controlled/regulated such that flow size is increased and recycle gas is mixed into the feed gas line when the pressure of the recycle gas lies above the pressure of the feed gas [0028]. That is, the valves disclosed in Millner open in response to the upstream pressure being higher than a threshold (i.e., the recycle gas line being higher pressure than a threshold).
Millner does not expressly teach the valve to the secondary circuit is a controllable valve responsive to a control unit which monitors input from a pressure sensor in the primary circuit upstream of a compressor.
Michigan provides an overview of the process control in the process engineering [Title] and discloses that pressure control in a process is critical for safety [page 1]. Michigan states that pressure control equipment consists of a transmitter (i.e. pressure sensor), a controller (i.e., a control unit) and a control element (i.e., a controllable valve) [Page 2]. Michigan teaches that a pressure transmitter is set such that it sends a signal to active a pressure control element when a set-point value is obtained [page 2].
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the system of Millner and included a pressure control system as described by Michigan in order to control when/how much gas flows into the secondary circuit area. Millner describes that the second circuit has a valve responsive to pressure(s) in the system and as such, an ordinarily skilled artisan would have had a reasonable expectation of success in applying the teachings. Moreover, an ordinarily skilled artisan would have been motivated to the apply the components of Michigan because these are vital for pressure control as well as process safety and moreover, would allow for automated control and monitoring of the system.
As described, the pressure sensor/transmitter and control unit of Michigan applied to Millner would be set such that the controllable valve would activate the when the pressure of the recycle gas line (“primary circuit”) was below the pressure of the gas line at 7” and above the pressure of the gas line at 7’ [Fig]. Moreover, the pressure sensor would need to be placed upstream of where the higher pressure line was connected so that the appropriate gas pressure was measured for determining when to open the controllable valve of 9”.
Moreover, given that the second circuit described in Millner is split from the first circuit upstream of the compressor “9”, it would have been obvious that the placement of the pressure sensor determining when gas enters the second circuit would also be upstream of the compressor as well.
Claims 14 – 15 are rejected under 35 U.S.C. 103 as being unpatentable over Millner (US2015/0007697) in view of Bechara (NPL, 2018) alone, or additionally in view of Michigan (“Pressure Relief and Control”; 2017), as applied to claim 13, in further view of Millner (US2014/0217653, henceforth referred to as “US ‘653” for clarity).
Regarding claim 14 – 15, Millner in view of Bechara alone, or in further view of Michigan teaches the invention as applied in claim 13. Millner does not expressly teach controlling the reduction gas flow from the source into the gas line based on the flow rate of gas through the gas line.
US ‘653 teaches a system in the same field of endeavor as Millner of producing direct-reduced metal using reduction gas and including a recycling line for the exhaust gas [Fig 1, Abstract]. US ‘653 teaches that prior to entrance into the reduction reactor, a device for regulating/monitoring the process gas volume is placed because the reduction reactor requires an almost constant volume of process gas to ensure quality [0026]. US ‘653 states that this can be achieved by regulation of the process gas volume [0029]. These teachings imply/meeting the broadest reasonable interpretation of a gas flow monitoring/measuring device in the gas line connected to a control unit. Moreover, US ‘653 teaches that the gas source line “2” has a valve [Fig 1], that the device for regulating process gas volume has control of valves [0047], and that the source has fluctuations in gas volume [0041]. As such, US ‘653 reasonably suggests controlling the source gas flow volume/valve based, at least in part, on the process gas volume in the gas line, meeting the claims 14 and 15.
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the system described by Millner as-modified and provided a valve for source gas flow regulation as well as a device for monitoring/controlling process gas flow volume/pressure and used this device to control the gas source flow volume/valve based, at least in part, on the process gas volume in the gas line, as suggested by US ‘653. US ‘653is in the same field of endeavor as Millner and both describe providing a gas source feed line combined with a recycle gas line. As such, an ordinarily skilled artisan would have had a reasonable expectation of success in modifying Millner as suggested by US ‘653. Moreover, an ordinarily skilled artisan would have been motivated to do so because US ‘653 expressly acknowledges that constant process gas flow volume is critical to the operation of the reduction reactor (and overall process) and that a device for regulating the process flow volume via control over valves allows for achieving this.
Claims 19 – 20 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Millner (US2015/0007697) in view of Bechara (NPL, 2018) alone, or additionally in view of Michigan (“Pressure Relief and Control”; 2017), as applied to claim 13, in further view of Zampa (WO2020165342, using US2022/0098686 as reference)
Regarding claims 19 – 20, Millner in view of Bechara alone, or in further view of Michigan teaches the invention as applied in claim 13. Millner teaches that the top gas is passed through a cleaning device but does not expressly disclose cleaning the gas by removing inert gas and/or water.
Zampa teaches a direct reduction system [title] in particular for iron (i.e., same field of endeavor as Zampa). Zampa discloses that the system includes a top gas recovery and treatment line which is returned, at least in part, to the reduction gas feed line [Fig 2]. Zampa discloses that upon exiting the reduction area the top gas is fed through a heat exchanger to cool the gas down [0075]. Zampa further discloses that the recycled top gas is then treated via a condensing unit to remove water [Fig 2, 0106], meeting the claimed limitation of claim 19. The dehydrated top gas line is then split to remove accumulated inert gases and subsequently treated to remove carbon dioxide [Fig 2, 0108, 0109], meeting the claimed limitation of claim 20.
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the system described by Millner as-modified and included steps/devices for condensing moisture and removing inert gases as described by Zampa. Zampa is in the same field of endeavor as Millner and both describe cleaning the top gas prior to recycling it back to the feed line. As such, an ordinarily skilled artisan would have had a reasonable expectation of success in modifying Millner as described by Zampa. Moreover, an ordinarily skilled artisan would have been motivated to do so because it would allow for removing/controlling components such as water and inert gas in order to control the composition quality of the recycled gas.
Regarding claim 22, Miller in view of Bechara alone, or in further view of Michigan teaches the invention as applied in claim 21. Millner teaches that the recycle loop (“15”) can comprise a heat exchanger [0039, “14”], but does not expressly teach that the gas line is also connected such that heat is transferred from top gas to reduction gas.
Zampa discloses a direct reduction system [title] in particular for iron (i.e., same field of endeavor as Zampa). Zampa discloses that the system includes a top gas recovery and treatment line which is returned, at least in part, to the reduction gas feed line [Fig 3]. Zampa discloses that upon exiting the reduction area the top gas is fed through a heat exchanger to cool the gas down [0075]. Zampa further discloses that once the recycled top gas and feed gas have been mixed, they can be fed through said heat exchanger to preheat the gas prior to being fed into a heating unit to achieve the final desired temperature [0089]. Zampa teaches that this configuration allows for exploiting the heat of the exiting top gas (i.e., reducing heater energy requirements by siphoning heat from top gas) [0089].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the system described by Millner as-modified and controlled the reduction gas feed line to pass through the heat exchanger of the top gas line such that heat is transferred, as described by Zampa. Zampa is in the same field of endeavor as Millner and both describe providing a heat exchanger to cool down the top gas exiting the reduction area. As such, an ordinarily skilled artisan would have had a reasonable expectation of success in modifying Millner as described by Zampa. Moreover, an ordinarily skilled artisan would have been motivated to do so because it would improve energy efficiency by exploiting the heat of used gas to preheat feed gas prior to the feed gas passing through a heater unit.
Claim 23 is rejected under 35 U.S.C. 103 as being unpatentable over Millner (US2015/0007697) in view of Bechara (NPL, 2018) alone, or additionally in view of Michigan (“Pressure Relief and Control”; 2017), as applied to claim 13, Meyer (“Direct Reduction Process by H2”, NPL).
Regarding claim 23, Millner in view of Bechara alone, or in further view of Michigan teaches the invention as applied in claim 13. Millner describes a feed line for a reduction gas [Fig 1] and that the reduction gas can be H2 gas [0025] but does not describe that the H2 gas is obtained via a water electrolyzer.
Meyer describes performing iron reduction via hydrogen gas, which is the most powerful reducer [page 1, 2]. Meyer describes that hydrogen gas can be produced by water electrolysis and fed into the reduction shaft [Page 3].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the system described by Millner as-modified and used a water electrolyzer to produce hydrogen gas, as described by Meyer. Meyer provides teachings regarding the reduction of iron and as such, an ordinarily skilled artisan would have considered the teachings pertinent to the method/system of Millner. Moreover, Millner acknowledges that the reduction gas can be H2 gas and as such, an ordinarily skilled artisan would have had a reasonable expectation of success in applying the teachings of Meyer to Millner to achieve predictable results with no change in the respective functions of the water electrolyzer of Meyer or process/system of Millner.
Relevant Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 10,260,117 – Direct reduction system with top gas recycling and storage and control unit
US2020/0385827 – DRI system with multiple gas loops
US2016/0186276 – Recycling lines for DRI shaft furnace
US 6,027,545 – Recycling of top gas for DRI process including separation of hydrogen and recycling
WO2021260225 – Direct reduction system with multiple recycle gas lines and control valves
WO2017046653 – direction reduction system with multiple recycle gas lines responsive to controllable valves
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AUSTIN POLLOCK whose telephone number is (571)272-5602. The examiner can normally be reached M - F (8 - 5).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sally Merkling can be reached on (571) 272-6297. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/AUSTIN POLLOCK/Examiner, Art Unit 1738
/SALLY A MERKLING/SPE, Art Unit 1738
Prosecution Insights