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 .
Election/Restrictions
Applicant's election with traverse of group I, claims 1-8 in the reply filed on 2 April 2026 is acknowledged. The traversal is on the ground(s) that the claims share special technical features which define a contribution over Zhang and Zhang teaches away from using low-pressure steam ("Remarks", pg. 8, par. 9; pg. 9, par. 2). This is not found persuasive because it appears that Finneran (US 3,441,393) in view of Osman (US 4,409,191) and Woodhouse (US 2010/0029466) and Athey (“Deaerating condenser boosts combined-cycle plant efficiency”) teaches the corresponding technical feature. See rejection below. Therefore, the restriction requirement is maintained.
The requirement is still deemed proper and is therefore made FINAL.
Claims 9-13 and 15 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected groups II and III, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 2 April 2026.
Response to Amendment
The Amendment filed 2 April 2026 has been entered. Claims 1, 9, and 15 are amended. Accordingly, claims 1-13 and 15 remain pending in the application with claims 1-8 considered in this Office Action.
Information Disclosure Statement
The Information Disclosure Statements filed 24 August 2023 and 12 November 2025 have been considered.
Claim Objections
Claim 1 is objected to because of the following informalities:
Claim 1, lines 8-9, "the solution to be regenerated" should read "the carbon dioxide absorption solution to be regenerated" for clarity.
Appropriate correction is required.
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 5-8 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 5, line 2, recites “30% potassium carbonate”. It is unclear what the percent is based on (i.e. volume, molar, weight). There does not appear to be support in the specification regarding the percentage basis. However, for examination purposes, this limitation is interpreted as requiring 30 wt% potassium carbonate.
Claim 6, lines 2-3, recite “about 30% potassium carbonate, about 5% potassium bicarbonate, about 0.5% diethanolamine and about 0.5% glycine”. It is unclear what the percent is based on (i.e. volume, molar, weight). There does not appear to be support in the specification regarding the percentage basis. However, for examination purposes, this limitation is interpreted as requiring weight percentages.
The term “essentially free” in claim 7, lines 4, 5, 7, and 14 is a relative term which renders the claim indefinite. The term “essentially free” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. The quantity associated with the amount of sulfur and carbon dioxide of claim 7 is therefore rendered indefinite by the use of the term "essentially free".
Claim 8 recites the limitation "the mixture of hydrogen and methane obtained from step l)" in line 3. There is insufficient antecedent basis for this limitation in the claim. This limitation is interpreted as requiring step l) produces a mixture of hydrogen and methane.
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.
Claims 1-8 are rejected under 35 U.S.C. 103 as being unpatentable over Finneran (US 3,441,393) in view of Osman (US 4,409,191) and Woodhouse (US 2010/0029466) and Athey (“Deaerating condenser boosts combined-cycle plant efficiency”).
Regarding Claim 1, Finneran discloses a gas containing carbon dioxide is contacted with a CO2 absorbent such as water, monoethanolamine, hot potassium carbonate (water and monoethanolamine meet the limitation of a carbon dioxide absorption solution) in an absorption zone (absorption zone meets the limitation of an absorption unit) for the absorption of carbon dioxide (absorption of carbon dioxide meets the limitation of capturing carbon dioxide; Col. 6, lines 26-32). Finneran further discloses the carbon dioxide-containing absorbent (aka carbon dioxide absorption solution) is heated by indirect heat exchange with warmer process streams to a temperature necessary for desorption of carbon dioxide in a regeneration zone (regeneration zone meets the limitation of a regenerator; Col. 6, lines 34-44). Heating by heat exchange in a regeneration zone meets the limitation of a heat exchange system comprising the regenerator, comprising the solution to be regenerated. Finneran further discloses the carbon dioxide-containing absorbent is heated by indirect heat exchange with 50 p.s.i.g. steam in a reboiling exchanger to partially vaporize the stream (heating with steam in a reboiling exchanger meets the limitation of a heat exchange system comprising a steam-fired reboiler; Col. 15, lines 51-60), such that steam is supplied to the steam-fired reboiler for supplying heat to the regenerator. Finneran further discloses regenerated absorbent is withdrawn and recycled to the absorber (Col. 16, lines 1-3). Finneran further discloses steam condensate resulting from using 50 p.s.i.g steam in heat exchanger 61 to supply the necessary heat for regeneration of carbon dioxide-containing absorbent with low-pressure steam (Col. 18, lines 6-11), such that Finneran meets the limitation wherein by the exchange of the heat of the steam in the steam-fired reboiler with the carbon dioxide absorption solution comprising absorbed carbon dioxide in the regenerator, the carbon dioxide absorption solution comprising absorbed carbon dioxide is heated, thereby producing a steam condensate and a regenerated carbon dioxide absorption solution.
Regarding the steam pressure in claim 1, it appears that 50 p.s.i.g. taught by Finneran, which is equivalent to 3.5 kg/cm2, meets the limitation, or in the alternative, overlaps the claimed range of 3.2-3.5 kg/cm2 such that the range taught by Finneran obviates the claimed range, and therefore meets the limitation of low-pressure steam. See MPEP 2144.05 (I).
Finneran is silent to further treating the regenerated carbon dioxide absorption solution exiting a high-pressure regenerator in a low-pressure regenerator.
Finneran, however, discloses conditions in the regeneration zone include a pressure of about 0 p.s.i.g. to about 20 p.s.i.g. (Col. 12, lines 32-34), which overlaps the claimed ranges of 1.0 to 1.2 kg/cm2 for the high-pressure regenerator and below 0.2 kg/cm2 for the low-pressure regenerator such that the range taught by Finneran obviates the claimed ranges. See MPEP 2144.05 (I).
Regarding the use of two regenerators, Osman discloses a process for removing acid gases such as CO2 from gas streams using a cyclic aqueous alkaline scrubbing solution (aqueous alkaline scrubbing solution meets the limitation of a carbon dioxide absorption solution) which is circulated between an absorption and regeneration stage (Abstract). Osman further discloses regeneration can be conducted in one or more steps (Col. 13, line 4). Osman further discloses the regeneration of absorbent solution is carried out in two columns of which the first operates at a higher pressure and the second operates at a lower pressure (Col. 12, lines 30-34). Osman further discloses multiple stage regeneration produces a more thoroughly regenerated scrubbing solution (Col. 13, lines 4-11). Osman further discloses regeneration occurs at about -5 to about 50 psig (Col. 12, lines 23-26), which is equivalent to -0.35 kg/cm2 to 3.5 kg/cm2, which overlaps the claimed ranges of 1.0 to 1.2 kg/cm2 for the high-pressure regenerator and below 0.2 kg/cm2 for the low-pressure regenerator such that the range taught by Osman obviates the claimed ranges. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Finneran to incorporate the teachings of Osman wherein the regenerated carbon dioxide absorption solution exiting the high-pressure regenerator is further treated in a low-pressure regenerator because multiple stage regeneration produces a more thoroughly regenerated scrubbing solution, as recognized by Osman (Col. 13, lines 4-11).
Regarding the pressures in the high-pressure regenerator and the low-pressure regenerator, Woodhouse discloses a method for regeneration of a rich absorbent having absorbed CO2 to give a regenerated absorbent (Abstract), wherein the pressure in the regeneration column is normally atmospheric pressure or higher to obtain an effective regeneration of the absorbent, or stripping of CO2 [0038].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Finneran to incorporate the teachings of Osman and Woodhouse, wherein the high-pressure regenerator operates at a pressure ranging from 1.0 to 1.2 kg/cm2 and the low-pressure regenerator operates at a pressure below 0.2 kg/cm2, as both Finneran and Osman teach regenerator pressures overlapping the pressures of the high-pressure regenerator and the low-pressure regenerator such that one of ordinary skill in the art at the time the invention was made would have optimized, by routine experimentation, the amount of pressure in the regenerators to obtain the desired effective regeneration of the adsorbent, or stripping of CO2, as recognized by Woodhouse [0038], since discovery of optimum ranges of a result effective variable in a known process is ordinarily within the skill of art and selection of the optimum ranges within the general condition is obvious (MPEP 2144.05 (II)).
Finneran further discloses the deaerator is fed with steam condensate (feeding the deaerator with steam condensate meets the limitation of directly supplying the steam condensate produced in step c) to a de-aerator) resulting from using steam in the heat exchange to supply the heat necessary for regeneration of carbon dioxide-containing absorbent (Col. 18, lines 5-11), such that Finneran meets the limitation of a method for treating a steam condensate generated by a regenerator for regenerating a carbon dioxide absorption solution. Finneran further discloses the deaerated water is sent to a steam generator for generating steam (Col. 18, lines 11-20), such that the deaerated water meets the limitation of an aqueous solution suitable for producing steam.
Finneran is further silent to producing an aqueous solution with an oxygen content lower than 20 ppb.
Finneran, however, discloses feeding steam condensate to a deaerator to produce deaerated water, and the deaerated water is then sent to a steam generator (Col. 18, lines 5-20).
Athey discloses deaeration of waste steam and providing deaerated water containing less than 7 ppb of oxygen to a steam generator (pg. 2, Col. 1, par. 4). Athey further discloses it is essential that feedwater be deaerated to 7 ppb of oxygen to prevent corrosion (less than 7 ppb of oxygen meets the limitation of an oxygen content lower than 20 ppb; pg. 2, Col. 1, par. 8).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Finneran to incorporate the teachings of Athey to deaerate the steam condensate thereby producing an aqueous solution suitable for producing steam with an oxygen content lower than 20 ppb, because it is essential that feedwater to a steam generator be deaerated to 7 ppb of oxygen to prevent corrosion, as recognized by Athey (pg. 2, Col. 1, par. 8).
Regarding Claim 2, Athey discloses deaeration of waste steam and providing deaerated water containing less than 7 ppb of oxygen to a steam generator (pg. 2, Col. 1, par. 4). Athey further discloses it is essential that feedwater be deaerated to 7 ppb of oxygen to prevent corrosion (pg. 2, Col. 1, par. 8), such that less than 7 ppb or 7 ppb taught by Athey meets the limitation, or in the alternative, is close to the claimed range of from 7 ppb to less than 20 ppb such that the range taught by Athey obviates the claimed range. See MPEP 2144.05 (I).
Regarding Claim 3, Finneran discloses regenerated absorbent is withdrawn and recycled to the absorber (Col. 16, lines 1-3), such that Finneran meets the limitation of re-using the regenerated carbon dioxide absorption solution produced in step c) for absorption additional carbon dioxide in the carbon dioxide absorption unit.
Regarding Claim 4, Finneran discloses the deaerated water (deaerated water meets the limitation of the aqueous solution produced in step d)) is sent to a steam generator for generating steam (Col. 18, lines 11-20).
Regarding Claim 5, Finneran discloses the CO2 absorbent may be potassium carbonate (Col. 6, lines 28-30).
Finneran is silent to a concentration of potassium carbonate in the absorption solution.
Osman discloses a regenerable aqueous alkaline scrubbing solution (aka absorption solution) comprising 15 to 45% by weight potassium carbonate (Col. 11, lines 35-45), which overlaps the claimed range of about 30% such that the range taught by Osman obviates the claimed range. See MPEP 2144.05 (I). Osman further discloses the absorption solution may be a lean solution having about a 10-25% conversion of potassium carbonate to potassium bicarbonate or a semi-lean solution having about a 30-50% conversion of potassium carbonate to potassium bicarbonate (Col. 14, lines 32-37).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Finneran to incorporate the teachings of Osman wherein the absorption solution comprises about 30% potassium carbonate and partly converted to potassium bicarbonate, as Finneran recognized potassium carbonate as a CO2 absorption solution, and utilizing an absorption solution comprising about 30% potassium carbonate and partly converted to potassium bicarbonate is a process parameter well-known in the art of CO2 absorption solutions, as recognized by Osman.
Regarding Claim 6, Finneran discloses the CO2 absorbent may be potassium carbonate (Col. 6, lines 28-30). Finneran further discloses absorbents may include diethanolamine (Col. 12, lines 23-26).
Finneran is silent to the carbon dioxide absorption solution comprises about 30% potassium carbonate, about 5% potassium bicarbonate, about 0.5% diethanolamine and about 0.5% glycine.
Osman discloses a regenerable aqueous alkaline scrubbing solution (aka absorption solution) comprising 15 to 45% by weight potassium carbonate (Col. 11, lines 35-45). Osman further discloses the absorption solution may be a lean solution having about a 10-25% conversion of potassium carbonate to potassium bicarbonate or a semi-lean solution having about a 30-50% conversion of potassium carbonate to potassium bicarbonate (Col. 14, lines 32-37), which, in the alternative, overlap the claimed ranges of about 30% potassium carbonate and about 5% potassium bicarbonate such that the ranges taught by Osman obviate the claimed ranges. See MPEP 2144.05 (I). Osman further discloses potassium carbonate solutions are preferably activated by the addition of additives such as amines, particularly ethanolamines (diethanolamine is an ethanolamine), amino acids such as glycine or other additives which tend to increase the rates of absorption and desorption of acid gas in the potassium carbonate solution (Col. 11, lines 47-53).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Finneran to incorporate the teachings of Osman to use a carbon dioxide absorption solution comprising about 30% potassium carbonate, about 5% potassium bicarbonate, diethanolamine, and glycine, because additives such as diethanolamine and glycine tend to increase the rates of absorption and desorption of acid gas in the potassium carbonate solution, as recognized by Osman (Col. 11, lines 47-53). Additionally, one of ordinary skill in the art at the time the invention was made would have optimized, by routine experimentation, the amount of diethanolamine and glycine to obtain the desired absorption and desorption rate of acid gas in the potassium carbonate solution, as recognized by Osman (Col. 11, lines 47-53), since discovery of optimum ranges of a result effective variable in a known process is ordinarily within the skill of art and selection of the optimum ranges within the general condition is obvious (MPEP 2144.05 (II)).
Regarding Claim 7, Finneran discloses natural gas is a suitable feed material (Col. 8, lines 64-67). Finneran further discloses feed is introduced in line 11 and mixed with synthesis gas to form a mixed stream, wherein the mixed stream in line 13 is preheated and introduced into a desulfurization zone 15 (desulfurization meets the limitation of removing sulfur and desulfurization zone meets the limitation of a sulfur removal unit) to produce a desulfurized effluent in line 16 (desulfurized effluent meets the limitation of natural gas essentially free of sulfur; Col. 14, lines 60-69; Fig. 1). Finneran further discloses mixing the desulfurized effluent with steam from line 17 and introducing into a primary reforming furnace 19 to produces effluent stream 22, which is introduced into a secondary reforming zone 23 to produce effluent stream in line 29 (Col. 14, line 68-Col. 15, line 17; Fig. 1), wherein the effluent of the primary reforming zone contains hydrogen and carbon monoxide (Col. 10, lines 23-24), such that the natural gas essentially free of sulfur is converted, using steam, into a mixture of carbon monoxide and hydrogen in a primary reformer (see the reaction of Col. 1, line 49). Finneran further discloses in addition to hydrogen, the chemical reactions of the secondary reforming produce carbon monoxide using oxygen (Col. 1, lines 50-51; Col. 2, lines 21-38), such that conversion of the feed of natural gas essentially free in sulfur is increased using oxygen to produce a mixture of carbon monoxide and hydrogen in a secondary reformer. Finneran further discloses effluent 29 from the secondary reforming furnace is introduced into shift converter 33 (shift converter meets the limitation of a shift conversion unit; Col. 15, lines 17-20; Fig. 1), wherein carbon monoxide present in the effluent is reacted with steam in the presence of a catalyst to form carbon dioxide and additional hydrogen in the shift conversion zone (Col. 2, lines 41-47). Finneran further discloses effluent 44 (effluent 44 meets the limitation of the gaseous mixture of carbon dioxide and hydrogen generated in step j)) of the shift converter is introduced into absorber 53 (absorber meets the limitation of the carbon dioxide absorption unit) where it is contacted with a regenerable CO2 absorbent (Col. 15, lines 37-49; Fig. 1). Finneran further discloses the gaseous effluent 81 from absorber 53 contains 73.8% hydrogen (Col. 16, lines 11-13; Fig. 1), wherein the purified stream from said absorption zone will contain only minor amounts of oxides of carbon (minor amounts meets the limitation of essentially free; Col. 6, lines 32-34). Finneran further discloses the gaseous effluent 81 (gaseous effluent 81 meets the limitation of hydrogen produced in step k)) from absorber 53 is introduced into methanator 82 (methanator meets the limitation of a methanation unit; Col. 16, lines 11-15; Fig. 1), wherein methanation is where the oxides of carbon (oxides of carbon include carbon monoxide and carbon dioxide and therefore meets the limitation of remaining amounts of carbon monoxide and carbon dioxide) react with hydrogen in the presence of a catalyst to form methane and water (Col. 6, lines 54-57).
Regarding Claim 8, Finneran further discloses the effluent stream 83 of the methanator 82 (effluent stream 83 meets the limitation of the mixture of hydrogen and methane obtained from step l)) is cooled at 84 and 86 and condensate is separated at 87; the uncondensed stream in line 89 is compressed at 92 and 93; the resulting stream of compressed gas in line 105 is cooled at 106 and condensate is separated at 107; uncondensed material containing 63.2% hydrogen in line 109 is heated at 111 and 112 and injected into the ammonia converter 113, which contains ammonia synthesis catalyst, to produce ammonia in line 123 (Col. 16, lines 15-61; Fig. 1), wherein the compressed synthesis gas reacted in the ammonia conversion reactor also comprises methane from the methanation zone (Col. 13, lines 19-25).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SLONE ELZABETH SIMKINS whose telephone number is (571)272-3214. The examiner can normally be reached Monday - Friday 8:30AM-4:30PM.
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/S.E.S./Examiner, Art Unit 1735
/PAUL A WARTALOWICZ/Primary Examiner, Art Unit 1735
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