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 1-10 and 15-18 in the reply filed on June 24, 2026 is acknowledged. The traversal is on the grounds that Wendlandt does not provide the disclosure missing from Watson. Although Wendlandt discloses a process for producing HNO3 from NH3, comprising the step of supplying pressurized O2 produced by pressure electrolysis, the O2 is only added to a reaction space at increased pressure for the oxidation of nitrogen oxides. However, the removal of remaining nitrogen oxides in the concentrated HNO3 is carried out by heating the concentrated HNO3 or by reducing the pressure without using a bleacher unit (see claims 1-4; p. 1, col. 1, I. 51 to col. 2, I. 10; p. 2, col. 4, 11. 7-21). Therefore, Wendlandt does not disclose or suggest the use of the O2 obtained by pressure electrolysis as a stripping medium in a bleacher unit.
This is not found persuasive because as clearly disclosed and explained in the restriction requirement, Wendlandt was brought to remedy the deficiency of Watson, which was the pressurized water electrolyser for use as a source of oxygen-rich gas at a pressure of 2 to 30 bar, for providing the bleacher unit with an oxygen-rich gas as a stripping medium via the inlet for the stripping medium. Examiner clearly explained how Wendlandt is in the same field of endeavor, how Wendlandt clearly teaches the importance of using pure oxygen in the process, and further, Wendlandt teaches that the pure oxygen may be produced by means of pressure electrolysis and the oxygen may be allowed to act upon the fluid at this pressure in the reaction space. Even, assuming arguendo, that Wendlandt teaches the removal of remaining nitrogen oxides in the concentrated HNO3 to be carried out by heating the concentrated HNO3 or by reducing the pressure without using the bleacher unit, Wendlandt provides sufficient reason and motivation to include a pressurized electrolyser in Watson’s system to use as a source of oxygen-rich gas at a pressure of 2 to 30 bar, for providing the bleacher unit with an oxygen-rich gas as a stripping medium via the inlet for the stripping medium, since Watson also requires the bleaching air for the bleacher unit to be enriched in oxygen and the oxygen used to enrich the bleaching air is meant to be pure oxygen (see restriction requirement and Watson column 5, lines 4-12), as claimed by the applicant, and hence arrive at the claimed invention.
In view of this, the argument is not considered persuasive and therefore, the requirement is still deemed proper and is therefore made FINAL. Claims 11-13 and 19 have been withdrawn as being directed to a non-elected invention.
Claim Objections
Claims 2-6 and 18 are objected to because of the following informalities: Language inconsistency.
Claims 2-4 and 18 recite: “The plant of claim 1…” Language consistency is recommended in order to avoid confusion.
For purposes of examination, examiner will interpret claims 2-4 and 18 as reciting: “The mono-pressure plant of claim 1…”
Claims 5-6 recite: “The plant of claim 4…” Language consistency is recommended in order to avoid confusion.
For purposes of examination, examiner will interpret claims 5-6 as reciting: “The mono-pressure plant of claim 4…”
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 1-10 and 15-18 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 1 recites the limitation “…for stripping the dissolved nitrogen oxides from the output product stream, thereby producing a first NOx-loaded stripping gas, the bleacher unit comprising an inlet for a stripping medium and an inlet for the product stream…” There is no mention of an output product stream previously in claim 1. Therefore, there is insufficient antecedent basis for this limitation in the claim.
For purposes of examination, examiner will interpret claim 1 as reciting: “…for stripping the dissolved nitrogen oxides from the product stream, thereby producing a first NOx-loaded stripping gas, the bleacher unit comprising an inlet for a stripping medium and an inlet for the product stream…”
Claim 2 recites: “…wherein the pressurized water electrolyser is connected to the mono-pressure plant such as to be at least partially powered by energy provided by the nitric acid plant.” There is no mention of a nitric acid plant previously in claim 1. Therefore, there is insufficient antecedent basis for this limitation in the claim.
Claim 3 recites: “…a liquid distributor comprising a feed box having a serrated weir for distribution of the output product stream…” There is no mention of an output product stream previously in claim 1. Therefore, there is insufficient antecedent basis for this limitation in the claim.
For purposes of examination, examiner will interpret claim 3 as reciting: : “…a liquid distributor comprising a feed box having a serrated weir for distribution of the product stream…”
Claim 6 recites: “The plant according to claim 4, wherein the working pressure is selected from the range of 9 bar to 16 bar, wherein the pressure in the first bleacher unit is at least 1 bar higher than the working pressure.” This limitation is considered indefinite. It is unclear as to how the first bleacher unit could operate at at least 1 bar higher than the working pressure, if the working pressure where to be at the maximum pressure of 16bar.
Claim 7 recites: “A method for continuously operating a bleacher unit in a plant according to claim 1, the ammonia convertor of the plant operating at a working pressure ranging from 2 bar to 16 bar, comprising consecutive steps of: (a) providing a first bleacher unit with an oxygen-rich gas from continuously operating a pressurized water electrolyser operating at a pressure of 2 bar to 30 bar, comprising more than 21 vol% oxygen as a stripping medium…” This limitation is considered indefinite because it is unclear if applicant is referring to the same first bleacher unit and the same pressurized water electrolyser as in claim 1 or if these are different, since claim 7 depends on claim 1 and these “first bleacher unit” and “pressurized water electrolyser” are disclosed in claim 7 as “a first bleacher unit” and “a pressurized water electrolyser” and not “the first bleacher unit” and “the pressurized water electrolyser” as making reference to those in claim 1.
For purposes of examination, examiner will interpret claim 7 as reciting: “A method for continuously operating a bleacher unit in a plant according to claim 1, the ammonia convertor of the plant operating at a working pressure ranging from 2 bar to 16 bar, comprising consecutive steps of: (a) providing the first bleacher unit with an oxygen-rich gas from continuously operating the pressurized water electrolyser operating at a pressure of 2 bar to 30 bar, comprising more than 21 vol% oxygen as the stripping medium…”
Claim 9 recites: “…wherein the pressurized water electrolyser is at least partially powered by energy provided by the nitric acid plant.” There is no mention of a nitric acid plant previously in claim 7. Therefore, there is insufficient antecedent basis for this limitation in the claim.
Claim 10 recites: “…wherein the method further comprises before step b), the step of: e) pre-heating the oxygen-rich gas as a stripping medium to a temperature of ambient temperature to 120ºC.” This limitation is considered indefinite because it is unclear if applicant is referring to the same stripping medium as in claims 1 or 7, or if this is a different stripping medium, since claim 9 depends on claim 7 and this “stripping medium” is disclosed in claim 9 as “a stripping medium” and not “the stripping medium” as making reference to the one in claim 7.
For purposes of examination, examiner will interpret claim 10 as reciting: “…wherein the method further comprises before step b), the step of: e) pre-heating the oxygen-rich gas as the stripping medium to a temperature of ambient temperature to 120ºC.”
Claims 4-5, 8 and 15-18 are rejected because they depend on rejected claim 1.
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.
Claim 1-2, 7-9 and 15-17 are rejected under 35 U.S.C. 103 as being unpatentable over Watson et al. (US Pat. No. 4,183,906, hereinafter Watson) in view of Wendlandt, R. (US Pat. No. 2,169,826, hereinafter Wendlandt).
In regards to Claim 1, Watson discloses a mono-pressure plant for a continuous production of nitric acid, comprising:
an ammonia convertor (#17), configured for operating at a working pressure ranging between 2 bar and 16 bar, for oxidizing ammonia, thereby producing a gaseous NOx gas/steam mixture, the ammonia convertor (#17) comprising at least one inlet for a stream of ammonia (#12) and pressurized air (#10), and an outlet (#18) for the gaseous NOx gas/steam mixture (see figure and column 8, lines 8-26 and lines 55-68; Watson discloses plant air is passed through compressor #3 where it is compressed from atmospheric pressure to a chosen pressure in the range of greater than 1 to 12 bars and carried to the converter #17. It is considered obvious, absent evidence to the contrary, that the ammonia convertor #17 is configured to operate at a working pressure of greater than 1 to 12 bars, which overlaps the claimed range of 2 to 16 bar, thereby making the claimed range prima facie obvious. See MPEP 2144.05.);
an air compressor (#3), in fluid communication with the ammonia convertor (#17), for pressurizing air to the working pressure (see figure and column 8, lines 8-21 and lines 55-64; Watson discloses plant air is passed through compressor #3 where it is compressed from atmospheric pressure to a chosen pressure in the range of greater than 1 to 12 bars and carried to the converter #17.);
an absorber unit (#28), configured for operating at the working pressure, wherein the nitrogen oxides contained in a gaseous NOx stream react with water, thereby producing nitric acid, the absorber unit (#28) comprising an inlet (#24) for a gaseous NOx stream, an inlet (#42) for an aqueous solution, an outlet for a product stream (#36) containing a nitric acid solution and dissolved nitrogen oxides, and an outlet (#40) for a tail gas (see figure and column 8, lines 26-45 and column 9, lines 9-33);
a first bleacher unit (#34), configured for operating at a pressure that is at least 0.01 bar to 1 bar higher than the working pressure reduced by a pressure drop in the ammonia convertor (#17) and during transport of the NOx gas stream to the absorber unit (#28), and up to 30 bar, for stripping the dissolved nitrogen oxides from the product stream (#36), thereby producing a first NOx-loaded stripping gas (#38), the bleacher unit (#34) comprising an inlet (inlet in communication with passage #8 and passage #32) for a stripping medium (passage #8 in communication with pipe #32 through which commercial oxygen may be passed into the passage #8 from a source (not shown)) and an inlet (#37) for the product stream (#36), an outlet (#38) for the first NOx-loaded stripping gas and an outlet (#44) for the stripped nitric acid stream (see figure and column 8, lines 45-54 and column 9, lines 35-47); and
a means (passage #38 which terminates in pipeline #23 for directing NOx-loaded stripping gas to inlet of absorbent unit #28) for directing the first NOx-loaded stripping gas to the inlet of the absorber unit (#28) (see figure and column 9, lines 16-19).
Watson discloses wherein the bleaching air is preferably enriched with oxygen upstream of (or in) the bleaching zone. Preferably, the oxygen is used to enrich the bleaching air is commercial oxygen by which is meant pure oxygen or a gas mixture containing at least 90% by volume of oxygen. Pure oxygen is added to the bleach air such that the quantity of oxygen flowing through the bleaching column is unaltered. Thus, a bleaching gas comprising oxygen-enriched air containing 33% oxygen by volume of oxygen, and 67% by volume of nitrogen is formed. This results in a total reduction of 36% in the rate of flow of gas through the bleaching column. Oxygen (substantially pure) is added to the column at a region where the absorption reaction is from 50 to 90% complete (see column 5, lines 4-11 and column 10, lines 35-51).
Watson is silent in regards to wherein the plant further comprises a pressurized water electrolyser as a source of oxygen-rich gas at a pressure of 2 to 30 bar, wherein the oxygen-rich gas comprises more than 21 vol% oxygen, for providing the bleacher unit with an oxygen-rich gas as a stripping medium via the inlet for the stripping medium.
However, Wendlandt, which is in the same field of endeavor, teaches a process and plant for producing highly concentrated nitric acid. Ammonia is oxidized with oxygen at atmospheric or at raised pressure in an ammonia converter (not shown) producing a gaseous NOx gas mixture. The process is effected in a single continuous operation by oxidizing ammonia with atmospheric air at pressure ranging between 2 and 10 atmospheres (2 to 10 bar). The NOx gas mixture is condensed, cooled, sent to a liquefier, and to an absorber where nitrogen oxides present are dissolved into a solution of highly concentrated nitric acid and nitrogen tetroxide, i.e. product stream containing nitric acid solution and dissolved nitrogen oxides. The solution of highly concentrated nitric acid and nitrogen tetroxide, i.e. product stream, is introduced into a bleacher. Oxygen gas needed for the bleacher (reaction space) may be produced under pressure, for instance by means of pressure electrolysis and the oxygen may be allowed to act upon the fluid at this pressure. The oxygen may also be directly fed to the reaction space of the bleacher through which the fluid is circulated, and the oxygen used should be completely pure (see figure 1, page 1, left column, line 51 to page 1, right column, line 10, page 2, left column, lines 57-69 and page 3, right column line 22 to page 4, left column line 12).
Since Watson discloses the importance of the bleaching air for the bleacher unit to be enriched in oxygen and the oxygen used to enrich the bleaching air is meant to be pure oxygen, and the commercial oxygen is passed into the passage from a source not shown (see column 5, lines 4-11 and column 8, lines 51-54), it would have been obvious by one of ordinary skill in the art before the effective filing date of the applicant’s invention to modify the mono-pressure plant as disclosed by Watson by further including a pressurized water electrolyser as a source of oxygen-rich gas at a pressure of 2 to 30 bar, for providing the bleacher unit with an oxygen-rich gas as a stripping medium via the inlet for the stripping medium, as claimed by the applicant, with a reasonable expectation of success, as Wendlandt teaches a process and plant for producing highly concentrated nitric acid, wherein ammonia is oxidized with oxygen at normal pressure in an ammonia converter producing a gaseous NOx gas mixture, the NOx gas mixture is condensed, cooled, sent to a liquefier, and to an absorber where nitrogen oxides present are dissolved into a solution of highly concentrated nitric acid and nitrogen tetroxide, i.e. product stream containing nitric acid solution and dissolved nitrogen oxides, whereby the solution of highly concentrated nitric acid and nitrogen tetroxide, i.e. product stream, is introduced into a bleacher, and oxygen gas needed for the bleacher (reaction space) may be produced under pressure, for instance by means of pressure electrolysis and the oxygen may be allowed to act upon the fluid at this pressure, whereby the oxygen may also be directly fed to the reaction space of the bleacher through which the fluid is circulated, whereby the oxygen used should be completely pure for efficiently separating nitric acid from the product stream (see figure 1, page 1, left column, line 51 to page 1, right column, line 10, page 2, left column, lines 57-69 and page 3, right column line 22 to page 4, left column line 12).
Examiner notes that the limitation regarding the plant further comprising means for lowering the pressure of the first NOx-loaded stripping gas to a pressure that is 0.01bar to 1bar higher than the working pressure, reduced by the pressure drop in the ammonia convertor and during transport of the NOx gas stream to the adsorber is an optional limitation, and therefore, does not need to be explicitly disclosed by the combination of Watson, in view of Wendlandt, in order to arrive at the claimed invention.
Examiner notes that although Watson, as modified above, is silent in regards to wherein the first bleacher unit is configured for operating at a pressure that is at least 0.01bar to 1 bar higher than the working pressure reduced by a pressure drop in the ammonia convertor, Watson, as modified above, discloses substantially the same mono-pressure plant as claimed by the applicant. Therefore, it is reasonably expected, absent evidence to the contrary, that Watson’s first bleacher unit is capable of functioning in the same manner as claimed, as it has been held that when the structure recited in the reference is substantially identical to that of the claims, claimed functions are considered prima facie obvious. See MPEP 2112.01.
In regards to Claim 2, Watson, in view of Wendlandt, discloses the mono-pressure plant as recited in claim 1. Although Watson, as modified above, does not explicitly disclose wherein the pressurized electrolyser is connected to the mono-pressure plant such as to be at least partially powered by energy provided by the mono-pressure plant, substituting a known energy source for another known energy source, such as for the pressurized electrolyser to be at least partially powered by energy provided by the mono-pressure plant is a mere engineering design choice, in order to obtain a desired end-result, such as for saving money on other alternative outside energy sources, and is considered prima facie obvious, absent evidence to the criticality or new or unexpected results. See MPEP 2144.04.
In regards to Claim 7, Watson, in view of Wendlandt, discloses the mono-pressure plant of claim 1.
Watson further discloses the ammonia converter (#17) of the plant operating at a working pressure of 2 bar to 16 bar (see figure and column 8, lines 8-26 and lines 55-68; Watson discloses plant air is passed through compressor #3 where it is compressed from atmospheric pressure to a chosen pressure in the range of greater than 1 to 12 bars and carried to the converter #17. It is considered obvious, absent evidence to the contrary, that the ammonia convertor #17 is configured to operate at a working pressure of greater than 1 to 12 bars, which overlaps the claimed range of 2 to 16 bar, thereby making the claimed range prima facie obvious. See MPEP 2144.05.), comprising the consecutive steps of:
providing the first bleacher unit (#34) with an oxygen-rich gas comprising more than 21 vol% oxygen as the stripping medium (see figure and column 8, lines 45-54 and column 9, lines 35-47; Watson discloses an inlet (inlet in communication with passage #8 and passage #32) for a stripping medium (passage #8 in communication with pipe #32 through which commercial oxygen may be passed into the passage #8 from a source (not shown));
operating the first bleacher unit (#34) at a pressure that is at least 0.01 bar to 1 bar higher than the working pressure reduced by the pressure drop in the ammonia convertor (#17) and during transport of the NOx gas stream to the absorber unit (#28), and up to 30 bar, thereby generating a first NOx-loaded stripping gas (#38) (see figure and column 8, lines 45-54 and column 9, lines 35-47);
directing the first NOx-loaded stripping gas (#38) to the inlet of the absorber unit (#28) (see figure and column 9, lines 16-19).
Examiner notes that the limitation regarding the plant further comprising means for lowering the pressure of the first NOx-loaded stripping gas to a pressure that is 0.01bar to 1bar higher than the working pressure, reduced by the pressure drop in the ammonia convertor and during transport of the NOx gas stream to the adsorber is an optional limitation, and therefore, does not need to be explicitly disclosed by the combination of Watson, in view of Wendlandt, in order to arrive at the claimed invention.
Examiner notes that although Watson, as modified above, is silent in regards to wherein the first bleacher unit is configured for operating at a pressure that is at least 0.01bar to 1 bar higher than the working pressure reduced by a pressure drop in the ammonia convertor, Watson, as modified above, discloses substantially the same mono-pressure plant as claimed by the applicant. Therefore, it is reasonably expected, absent evidence to the contrary, that Watson’s first bleacher unit is capable of functioning in the same manner as claimed, as it has been held that when the structure recited in the reference is substantially identical to that of the claims, claimed functions are considered prima facie obvious. See MPEP 2112.01.
In regards to Claim 8, Watson, in view of Wendlandt, discloses the method as recited in claim 7. Watson discloses wherein the oxygen used to enrich the bleaching air is commercial oxygen by which is meant pure oxygen or a gas mixture containing at least 90% by volume of oxygen to make possible the selection of a rate of feeding secondary air into the absorption zone or zones which can give favorable residence times and oxygen partial pressure at the bottom of the column (see column 5, lines 4-18). Wendlandt further teaches wherein the oxygen-rich gas comprises more than 95 vol% of oxygen (see page 2, left column, lines 57-69; Wendlandt teaches wherein the oxygen may be produced under pressure by means of pressure electrolysis, and the oxygen may be allowed to act upon the fluid at this pressure. The oxygen used should preferably be completely pure. Therefore, it is considered reasonably obvious, absent evidence to the contrary, that the oxygen-rich gas comprises more than 95 vol% of oxygen, as claimed by the applicant.).
It would have been obvious by one of ordinary skill in the art before the effective filing date of the applicant’s invention to modify the method as disclosed by Watson by having the oxygen-rich gas to comprise more than 95 vol% of oxygen, as claimed by the applicant, with a reasonable expectation of success, as Wendlandt teaches that the oxygen may be produced under pressure by means of pressure electrolysis, whereby the oxygen may be allowed to act upon the fluid at this pressure and the oxygen used should preferably be completely pure (see page 2, left column, lines 57-69).
In regards to Claim 9, Watson, in view of Wendlandt, discloses the method as recited in claim 7. Although Watson, as modified above, does not explicitly disclose wherein the pressurized electrolyser is at least partially powered by energy provided by the mono-pressure plant, substituting a known energy source for another known energy source, such as for the pressurized electrolyser to be at least partially powered by energy provided by the mono-pressure plant is a mere engineering design choice, in order to obtain a desired end-result, such as for saving money on other alternative outside energy sources, and is considered prima facie obvious, absent evidence to the criticality or new or unexpected results. See MPEP 2144.04.
In regards to Claim 15, Watson discloses wherein the stream of ammonia and pressurized air is an ammonia/pressurized air mixture (see figure and column 8, lines 14-21).
In regards to Claim 16, Watson, in view of Wendlandt, discloses the mono-pressure plant as recited in claim 1. Watson discloses wherein the absorber unit (#28) is configured for operating at the working pressure reduced by the pressure drop in the ammonia convertor (#17) and during transport of the NOx gas stream to the absorber unit (#28) (see figure, column 1, lines 65-68, column 8, lines 26-45 and column 9, lines 9-33).
In regards to Claim 17, Watson, in view of Wendlandt, discloses the mono-pressure plant as recited in claim 1. Watson discloses wherein the absorber unit (#28) is configured for operating at the working pressure reduced by 0.01 bar to 1bar (see column 1, lines 65-68, column 8, lines 26-45 and column 9, lines 9-33).
Examiner’s Comments
In regards to Claims 3-6, 10 and 18, no art rejection has been made for these claims. These have only been rejected under 35 USC § 112(b), as explained in the above office action.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JELITZA M PEREZ whose telephone number is (571)272-8139. The examiner can normally be reached Monday-Friday 9:00am-6:00pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Claire Wang can be reached at (571) 270-1051. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JELITZA M PEREZ/Primary Examiner, Art Unit 1774
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