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 .
Priority
Acknowledgment is made of applicant's claim for foreign priority based on an application filed in Japan on February 19th, 2024. It is noted, however, that applicant has not filed a certified copy of the JP 2024-022972 application as required by 37 CFR 1.55.
Drawings
New corrected drawings in compliance with 37 CFR 1.121(d) are required in this application
because the submitted drawings have a line quality that is too light to be reproduced (weight of all lines and letters must be heavy enough to permit adequate reproduction) or text that is illegible (reference characters, sheet numbers, and view numbers must be plain and legible). See 37 CFR 1.84(l) and (p)(1). Applicant is advised to employ the services of a competent patent draftsperson outside the Office, as the U.S. Patent and Trademark Office no longer prepares new drawings. The corrected drawings are required in reply to the Office action to avoid abandonment of the application. The requirement for corrected drawings will not be held in abeyance.
Claim Objections
Claims 1-7 are objected to because of the following informalities:
Claim 1, lines 2-3: “a main heat exchanger comprising feed air introduced from a warm end
thereof and drawn from a cold end thereof” should read “main heat exchanger comprising feed air introduced from a warm end of the main heat exchanger and drawn from a cold end of the main heat exchanger”
Claim 1, line 4: “into configured” should read “configured”
Claim 1, line 6: “into configured” should read “configured”
Claim 1, line 9: “into configured” should read “configured”
Claim 1, line 12: “condenser, after” should read “condenser after”
Claim 1, line 15: “column, after” should read “column after”
Claim 1, line 16: “exchanger, been” should read “exchanger and has been”
Claim 2, line 1: “further comprising” should read “further comprising:”
Claim 2, line 2: “into configured” should read “configured”
Claim 2, line 4: “into configured” should read “configured”
Claim 3, line 2: “nitrogen gas” should read “the nitrogen gas”
Claim 3, line 3: “nitrogen gas” should read “the nitrogen gas”
Claim 3, line 5: “to branch the” should read “to branch from the”
Claim 3, lines 7-8: “to draw out out” should read “to draw out”
Claim 3, line 8: “nitrogen gas” should read “the nitrogen gas”
Claim 3, line 12: “to bypasds” should read “to bypass”
Claim 3, line 12: “nitrogen gas” should read “the nitrogen gas”
Claim 3, line 13: “introduced therein” should read “introduced into the main heat exchanger”
Claim 3, line 15: “nitrogen gas” should read “the nitrogen gas”
Claim 4, line 2: “nitrogen gas” should read “the nitrogen gas”
Claim 4, line 3: “nitrogen gas” should read “the nitrogen gas”
Claim 4, line 8: “nitrogen gas” should read “the nitrogen gas”
Claim 5, line 1: “further comprising” should read “further comprising:”
Claim 5, line 3: “nitrogen gas” should read “the nitrogen gas”
Claim 5, line 4: “nitrogen gas” should read “the nitrogen gas”
Claim 7, line 1: “further comprising” should read “further comprising:”
Claims 2-4 and 7 are also objected to by virtue of their dependency on claim 1.
Claims 5-6 are also objected to by virtue of their dependency on claim 1.
Appropriate correction is required.
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.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are:
Claim 4, line 14: “cooling unit” draws corresponding structure to the heat exchangers 15 and/or 18 as shown in Figures 3-5, or equivalents thereof.
Claim 6, line 5: “cooling unit” draws corresponding structure to the heat exchangers 15 and/or 18 as shown in Figures 3-5, or equivalents thereof.
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
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 1-7 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, lines 7-8 recite, “the vapour stream being condensed and drawn out as a reflux liquid” which renders indefinite the metes and bounds sought for protection of the claim. In the instant case, the claim recites both an apparatus and process in the same claim. Per MPEP 2173.05(p): “[a] single claim which claims both an apparatus and the method steps of using the apparatus is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.” The Examiner recommends amending the claim to recite this limitation either structurally or as intended use.
Claim 2, lines 5-6 recite, “the vapour stream being condensed and drawn out as a reflux liquid” which renders indefinite the metes and bounds sought for protection of the claim. In the instant case, the claim recites both an apparatus and process in the same claim. Per MPEP 2173.05(p): “[a] single claim which claims both an apparatus and the method steps of using the apparatus is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.” The Examiner recommends amending the claim to recite this limitation either structurally or as intended use.
Claim 3, lines 5-8 recite, “a nitrogen gas branch pipeline…configured to draw out out nitrogen gas from an intermediate portion” which is unclear to the Examiner as to what the intermediate portion is a portion of (i.e., an intermediate portion of the nitrogen gas branch pipeline or an intermediate portion of the main heat exchanger). For purposes of examination, the Examiner will interpret the intermediate portion to be an intermediate portion of the main heat exchanger. The Examiner recommends amending the claim as interpreted herein.
Claim 3, lines 8-10 recite, “the nitrogen gas then being expanded by the nitrogen turbine and merged into the nitrogen gas pipeline or extracted as nitrogen gas once again via the main heat exchanger” which renders indefinite the metes and bounds sought for protection of the claim. In the instant case, the claim recites both an apparatus and process in the same claim. Per MPEP 2173.05(p): “[a] single claim which claims both an apparatus and the method steps of using the apparatus is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.” The Examiner recommends amending the claim to recite this limitation either structurally or as intended use.
Claim 4, lines 5-8 recite, “a nitrogen gas branch pipeline…configured to draw out nitrogen gas from an intermediate portion” which is unclear to the Examiner as to what the intermediate portion is a portion of (i.e., an intermediate portion of the nitrogen gas branch pipeline or an intermediate portion of the main heat exchanger). For purposes of examination, the Examiner will interpret the intermediate portion to be an intermediate portion of the main heat exchanger. The Examiner recommends amending the claim as interpreted herein.
Claim 4, lines 8-10 recite, “the nitrogen gas then being expanded by the nitrogen turbine and merged into the nitrogen gas pipeline or extracted as nitrogen gas once again via the main heat exchanger” which renders indefinite the metes and bounds sought for protection of the claim. In the instant case, the claim recites both an apparatus and process in the same claim. Per MPEP 2173.05(p): “[a] single claim which claims both an apparatus and the method steps of using the apparatus is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.” The Examiner recommends amending the claim to recite this limitation either structurally or as intended use.
Claim 4, line 12 recites, “a predetermined pressure” which is unclear to the Examiner as to how the predetermined pressure of claim 4 relates to the previously claimed predetermined pressure of claim 1 from which claim 4 depends. For purposes of examination, the Examiner will interpret the predetermined pressure of claim 4 and the predetermined pressure of claim 1 to be different predetermined pressures.
Claim 6, line 3 recites, “a predetermined pressure” which is unclear to the Examiner as to how the predetermined pressure of claim 4 relates to the previously claimed predetermined pressure of claim 1 from which claim 4 depends. For purposes of examination, the Examiner will interpret the predetermined pressure of claim 4 and the predetermined pressure of claim 1 to be different predetermined pressures.
Claim 7, lines 3-4 recite, “introduced from a warm end and drawn from a cold end” which is unclear to the Examiner as to component the warm end and the cold end are portions of (i.e., the medium-pressure rectification column or the sub-cooler). For purposes of examination, the Examiner will interpret the claim to read “introduced from a warm end of the sub-cooler and drawn from a cold end of the sub-cooler”. The Examiner recommends amending the claim interpreted herein.
Claims 2-4 and 7 are also rejected by virtue of their dependency on claim 1.
Claims 5-6 are also rejected by virtue of their dependency on claim 1.
Examiner Notes
Claim 5, lines 1-5 recite, “The air separation unit according to claim 3, further comprising a recycling nitrogen line configured to branch from the nitrogen gas branch pipeline inside the main heat exchanger, configured to draw nitrogen gas out from the cold end of the main heat exchanger, and configured to introduce nitrogen gas into the medium-pressure rectification column.” The Examiner notes that per the figures and the specification the embodiment of Figure 2, which is described by claim 3, does not include a recycling nitrogen. This is further evidenced by the following recitation of the present disclosure, “The air separation units (A4, A5) may comprise: a recycling nitrogen line (L431 b) which branches from the nitrogen gas branch pipeline (L431) inside the main heat exchanger (1 ), draws nitrogen gas out from the cold end of the main heat exchanger (1), and serves to introduce nitrogen gas into the rectification portion (22) or the upper portion (23) of the medium-pressure rectification column (2); and a valve (V2) provided in the recycling nitrogen line (L431 b) (Pg. 9, lines 3-9)”. Therefore, the Examiner believes a dependency error has been made and claim 5 should not depend from claim 3.
Claim 6, lines 1-7 recite, “The air separation unit according to claim 3, further comprising: a second nitrogen booster which is provided in the nitrogen gas branch pipeline and configured to boost the pressure of the nitrogen gas to a predetermined pressure; and a second cooling unit which is provided in the nitrogen gas branch pipeline and configured to cool the nitrogen gas pressure-boosted by the second nitrogen booster.” The Examiner notes that per the figures and the specification the embodiment of Figure 2, which is described by claim 3, does not include a second nitrogen booster nor a second cooling unit. This is further evidenced by the following recitation of the present disclosure, “The air separation units (A3, A4, A5) may comprise: a nitrogen booster (14) which is provided in the nitrogen gas branch pipeline (L431) and boosts the pressure of the nitrogen gas to a predetermined pressure; a second cooling unit (15) for cooling the nitrogen gas pressure-boosted by the nitrogen booster (14) (Pg. 8, lines 17-21)”. Therefore, the Examiner believes a dependency error has been made and claim 6 should not depend from claim 3.
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.
Claims 1-2 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Hirose et al. (US 20190293347), hereinafter Hirose in view of Bauer et al. (US 20110209498), hereinafter Bauer.
Regarding claim 1, Hirose discloses an air separation unit (Fig. 1, apparatus 100) comprising:
a main heat exchanger comprising feed air introduced from a warm end thereof and drawn from a cold end thereof (Fig. 1, main heat exchanger 1; Pg. 6-7, paragraph 114, Inside the main heat exchanger 1, the raw air undergoes heat exchange with at least one of the product nitrogen gas, condenser gas and intermediate portion gas which will be described later. The raw air is cooled to close to the liquefaction point thereof as a result. The temperature of the raw air is 20° C., for example, when it is introduced into the main heat exchanger 1, and it is cooled in the main heat exchanger 1 to between -170° C. and -155° C., for example);
a medium-pressure rectification column into configured to introduce the feed air drawn from the main heat exchanger (Fig. 1, first rectification column 2; Pg. 7, paragraph 115, The raw air cooled in the main heat exchanger 1 is introduced into the first rectification column 2 where it is rectified. The number of theoretical plates in the first rectification colunm 2 is between 30 plates and 80 plates, and may be set at 50 plates, for example. The operating pressure range in the first rectification column 2 is 7 barA-15 barA, and the operating pressure may be set at 9 barA, for example);
a nitrogen condenser into configured to introduce a vapour stream from the medium-pressure rectification column, the vapour stream being condensed and drawn out as a reflux liquid (Fig. 1, first condenser 3; Pg. 7, paragraph 118-119, A first condenser 3 is arranged in such a way as to perform heat exchange between the gas accumulated in the colunm top portion of the first rectification colunm and the liquid accumulated in the colunm bottom portion of the second rectification column. The raw air is separated into oxygen-enriched liquid and nitrogen gas in the first rectification column 2, and the oxygen-enriched liquid is accumulated in the colunm bottom portion of the first rectification column 2. The separated nitrogen gas is condensed in the first condenser 3 to form liquid nitrogen. The oxygen-enriched liquid which will be described later is utilized as a refrigerant in the first condenser 3 as a result of dropping down in the interior of the second rectification column 5 arranged above the condenser 3. At least a portion of the liquid nitrogen obtained as a result of being condensed in the first condenser 3 (e.g., between 10% and 97% of the liquid nitrogen condensed in the first condenser 3) passes through the nitrogen-containing liquid introduction pipe 11 and is introduced as a reflux liquid into an upper portion of the second rectification column 5);
a low-pressure rectification column into configured to introduce an oxygen-rich liquid drawn from the medium-pressure rectification column (Fig. 1, second rectification column 5; Pg. 7, paragraph 116, The product nitrogen gas is extracted from the column top portion of the second rectification column 5. The number of theoretical plates in the second rectification column 5 is between 40 plates and 120 plates, and may be set at 80 plates, for example. The operating pressure range in the second rectification column 5 is 1.5 barA-6 barA, and the operating pressure may be set at 2.5 barA, for example; Pg. 7, paragraph 121, The oxygen-enriched liquid accumulated in the column bottom portion of the first rectification column 2 is drawn from the column bottom portion of the first rectification column by means of an oxygen-enriched liquid drawing pipe 21. Some or all of the oxygen-enriched liquid (e.g., between 10% and 100% of the oxygen-enriched liquid accumulated in the column bottom portion) is introduced into the second rectification column 5 via the first oxygen-enriched liquid introduction pipe 12, and the portion of the oxygen-enriched liquid accumulated in the column bottom portion of the first rectification column 2 which is not introduced into the second rectification column 5 is introduced into the third rectification column 6 via the second oxygen-enriched liquid introduction pipe 13);
an oxygen turbine for expanding and cooling an oxygen-rich gas drawn from the nitrogen condenser, after the oxygen-rich gas has undergone heat exchange in the main heat exchanger (Fig. 1, expansion turbine 8; Pg. 8, paragraph 128, The condenser gas drawing pipe 14 and the intermediate portion gas drawing pipe 15 merge at a stage before the main heat exchanger 1, and the intermediate portion gas and the condenser gas are mixed at that stage. The oxygen concentration in the mixed gas is between 70% and 97%, for example; Pg. 8, paragraph 130; The expansion turbine 8 is an expansion turbine for expanding and cooling the mixed gas comprising the intermediate portion gas and the condenser gas after said mixed gas has passed through the main heat exchanger 1 and the cold has been released therefrom as a result of undergoing heat exchange with the raw air in the interior of the main heat exchanger 1).
However, Hirose does not disclose a nitrogen turbine for expanding nitrogen gas drawn from the low-pressure rectification column, after said nitrogen gas has undergone heat exchange at least in the main heat exchanger, been compressed to a predetermined pressure and cooled, and once again cooled in the main heat exchanger.
Bauer teaches a nitrogen turbine for expanding nitrogen gas drawn from the low-pressure rectification column, after said nitrogen gas has undergone heat exchange at least in the main heat exchanger, been compressed to a predetermined pressure and cooled, and once again cooled in the main heat exchanger (Fig. 2, low-pressure column T2, line 4, line 4’, line 9, compressor C, line 9’, line 15, expansion turbine X, line 15’; Pg. 2, paragraph 28-29, In contrast to the procedure shown in FIG. 1, in the procedure shown in FIG. 2, now, at least occasionally, a substream of the compressed nitrogen-rich fraction 9" which was condensed in heat exchanger El is taken off via line 16, expanded in valve f and fed via line 17 to the nitrogen-rich fraction in line 4'. Together with this, the expanded substream is vaporized at least in part, preferably completely, in heat exchanger E1 for the purpose of cold generation. After the nitrogen-rich fraction in compressor C is compressed preferably to a pressure between 20 and 80 bar, in valve f it is preferably expanded to a pressure between 1 and 20 bar. Via line 15, in addition, at least occasionally, a substream of the compressed nitrogen-rich fraction, after cooling
thereof in heat exchanger El, can be taken off and cold producingly expanded in expansion turbine X. The expanded substream is subsequently likewise fed to the nitrogen-rich fraction in line 4' via line 15' and warmed in heat exchanger E1 for the purpose of cold generation. By means of this embodiment the additional refrigeration performance is increased).
Therefore, it would have been obvious before the effective filing date of the claimed invention to modify the air separation unit of Hirose of claim 1 to include a nitrogen turbine for expanding nitrogen gas drawn from the low-pressure rectification column, after said nitrogen gas has undergone heat exchange at least in the main heat exchanger, been compressed to a predetermined pressure and cooled, and once again cooled in the main heat exchanger as taught by Bauer. One of ordinary skill in the art would have been motivated to make this modification to increase the refrigeration performance of the system (Bauer, Pg. 2, paragraph 29).
Further, Hirose as modified teaches the claimed invention except for “an inlet temperature of the oxygen turbine is lower than an inlet temperature of the nitrogen turbine”. It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include “an inlet temperature of the oxygen turbine is lower than an inlet temperature of the nitrogen turbine”, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges [or optimum value] involves only routine skill in the art. In re Aller, 105 USPQ 233. MPEP 2144.05-II-A.
Moreover, since applicants have not disclosed that these modifications solve any stated problem or are for any particular purpose and it appears that the device would perform equally well with either designs, these modifications are a matter of design choice. Absent a teaching as to criticality of “an inlet temperature of the oxygen turbine is lower than an inlet temperature of the nitrogen turbine”, this particular arrangement is deemed to have been known by those skilled in the art since the instant specification and evidence of record fail to attribute any significance (novel or unexpected results) to a particular arrangement. In re Kuhle, 526 F.2d 553,555,188 USPQ 7, 9 (CCPA 1975). MPEP 2144.05.
Regarding claim 2, Hirose as modified discloses the air separation unit according to claim 1 (see the combination of references used in the rejection of claim 1 above), further comprising
a crude argon column into configured to introduce an oxygen-containing fluid drawn from the low-pressure rectification column (Hirose, Fig. 1, third rectification column 6; Pg. 7, paragraph 121, The oxygen-enriched liquid accumulated in the column bottom portion of the first rectification column 2 is drawn from the column bottom portion of the first rectification column by means of an oxygen-enriched liquid drawing pipe 21. Some or all of the oxygen-enriched liquid (e.g., between 10% and 100% of the oxygen-enriched liquid accumulated in the column bottom portion) is introduced into the second rectification column 5 via the first oxygen-enriched liquid introduction pipe 12, and the portion of the oxygen-enriched liquid accumulated in the column bottom portion of the first rectification column 2 which is not introduced into the second rectification column 5 is introduced into the third rectification column 6 via the second oxygen-enriched liquid introduction pipe 13); and
a crude argon condenser into configured to introduce a vapour stream from the crude argon column, the vapour stream being condensed and drawn out as a reflux liquid (Hirose, Fig. 1, second condenser 7; Pg. 7, paragraph 125, The second oxygen-enriched liquid introduction pipe 13 is disposed in such a way that the oxygen-enriched liquid is introduced into the second condenser disposed in the upper region of the third rectification column 6. The oxygen-enriched liquid which has passed through the second oxygen-enriched liquid introduction pipe 13 is utilized as a refrigerant in the second condenser 7 in order to cause condensation of the argon gas rising up in the interior of the third rectification column 6. The oxygen-enriched liquid vaporized in the second condenser 7 may be expelled from the second condenser 7, after which it may merge in the first oxygen-enriched liquid introduction pipe 12, and may be introduced into the second rectification column 5; Pg. 8, paragraph 136, The argon-containing gas introduced into the third rectification column 6 is separated by means of rectification into an oxygen-enriched argon-containing liquid and product argon gas. The product argon gas is drawn from the product argon gas drawing pipe 18. Meanwhile, the oxygen-enriched argon-containing liquid accumulated in the column bottom portion of the third rectification column 6 is introduced into the second rectification column 5 via an argon containing liquid drawing pipe 19. The position of the argon-containing liquid drawing pipe 19 is below the product argon gas drawing pipe 18).
Regarding claim 7, Hirose as modified discloses the air separation unit according to claim 1 (see the combination of references used in the rejection of claim 1 above), further comprising a subcooler which is configured to accept an oxygen-rich liquid drawn from the medium-pressure rectification column introduced from a warm end and drawn from a cold end (Hirose, Fig. 1, sub-cooler 4; Pg. 8, paragraph 132, The product nitrogen gas undergoes heat exchange with the nitrogen-containing liquid and oxygen-enriched liquid in the interior of the sub-cooler 4. That is to say, the cold of the product nitrogen gas is utilized to cool the nitrogen-containing liquid and the oxygen-enriched liquid in the interior of the sub-cooler 4).
Claims 3 is rejected under 35 U.S.C. 103 as being unpatentable over Hirose as modified by Bauer as applied to claim 1 above, and further in view of Ayres et al. (US Patent No. 4,783,210), hereinafter Ayres.
Regarding claim 3, Hirose as modified discloses the air separation unit according to claim 1 (see the combination of references used in the rejection of claim 1 above), further comprising:
a nitrogen gas pipeline configured to draw nitrogen gas from the low-pressure rectification column and extracts nitrogen gas at least via the main heat exchanger (Hirose, Fig. 1, product nitrogen gas drawing pipe 16; Pg. 8, paragraph 131, The product nitrogen gas drawing pipe 16 is a pipe for drawing the product nitrogen gas from the column top portion of the second rectification column 5. The temperature of the product nitrogen gas which has been drawn is in a range of between -192° C. and -175° C., and it may be supplied as nitrogen gas without further treatment, but it may equally be introduced into the main heat exchanger 1 where it may undergo heat exchange with the raw air, whereby the cold may be released therefrom, and said nitrogen gas may be supplied as nitrogen gas at a temperature of between 0° C. and 20° C., for example. In addition, said nitrogen gas may also undergo heat exchange in the sub-cooler 4 before introduction into the main heat exchanger 1);
a nitrogen gas branch pipeline configured to branch the nitrogen gas pipeline downstream from the main heat exchanger, configured to introduce the nitrogen gas from the warm end of the main heat exchanger, configured to draw out nitrogen gas from an intermediate portion, the nitrogen gas then being expanded by the nitrogen turbine and merged into the nitrogen gas pipeline or extracted as nitrogen gas once again via the main heat exchanger (Bauer, Fig. 2, line 9, compressor C, line 9’, line 15, expansion turbine X, line 15’; Pg. 2, paragraph 28-29, In contrast to the procedure shown in FIG. 1, in the procedure shown in FIG. 2, now, at least occasionally, a substream of the compressed nitrogen-rich fraction 9" which was condensed in heat exchanger El is taken off via line 16, expanded in valve f and fed via line 17 to the nitrogen-rich fraction in line 4'. Together with this, the expanded substream is vaporized at least in part, preferably completely, in heat exchanger E1 for the purpose of cold generation. After the nitrogen-rich fraction in compressor C is compressed preferably to a pressure between 20 and 80 bar, in valve f it is preferably expanded to a pressure between 1 and 20 bar. Via line 15, in addition, at least occasionally, a substream of the compressed nitrogen-rich fraction, after cooling thereof in heat exchanger El, can be taken off and cold producingly expanded in expansion turbine X. The expanded substream is subsequently likewise fed to the nitrogen-rich fraction in line 4' via line 15' and warmed in heat exchanger E1 for the purpose of cold generation. By means of this embodiment the additional refrigeration performance is increased).
However, Hirose as modified does not disclose a bypass line configured to branch from the nitrogen gas branch pipeline, configured to bypass a heat exchanger so that nitrogen gas is not introduced therein, and configured to merge with the nitrogen gas branch pipeline; and
a regulating valve for regulating an amount of nitrogen gas circulating through the bypass line.
Ayres teaches a bypass line configured to branch from a gas pipeline, configured to bypass the main heat exchanger so that gas is not introduced therein, and configured to merge with the gas pipeline (Fig. 1, line 101, heat exchanger 9, line 97, line 103; Col. 8, lines 9-14, The warmed stream, now in line 95, is split into two substreams, lines 97 and 101, respectively. Substream 97 bypasses heat exchanger 9 by passing through valve 99 and is reunited with substream 101 which has been warmed in heat exchanger 9); and
a regulating valve for regulating an amount of gas circulating through the bypass line (Fig. 1, valve 99; Col. 8, lines 9-14, The warmed stream, now in line 95, is split into two substreams, lines 97 and 101, respectively. Substream 97 bypasses heat exchanger 9 by passing through valve 99 and is reunited with substream 101 which has been warmed in heat exchanger 9; Further, the teachings of Ayres at least imply the valve 99 can regulate amount of gas circulating through the bypass line since it has been held in considering the disclosure of a reference, it is proper to take into account not only specific teachings of the reference but also the inferences which one skilled in the art would reasonably be expected to draw therefrom (MPEP 2144.01)).
Hirose as modified fails to teach a bypass line configured to branch from the nitrogen gas branch pipeline, configured to bypass a heat exchanger so that nitrogen gas is not introduced therein, and configured to merge with the nitrogen gas branch pipeline and a regulating valve for regulating an amount of nitrogen gas circulating through the bypass line, however Ayres teaches that it is a known method in the art of air separation units to include a bypass line configured to branch from a gas pipeline, configured to bypass the main heat exchanger so that gas is not introduced therein, and configured to merge with the gas pipeline and a regulating valve for regulating an amount of gas circulating through the bypass line. This is strong evidence that modifying Hirose as modified as claimed would produce predictable results (i.e. controlling the refrigeration capacity available in the heat exchanger to improve overall system efficiencies). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hirose as modified by Ayres and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of controlling the refrigeration capacity available in the heat exchanger to improve overall system efficiencies.
Claims 4 is rejected under 35 U.S.C. 103 as being unpatentable over Hirose as modified by Bauer as applied to claim 1 above, and further in view of Agrawal et al. (US Patent No. 5,255,524), hereinafter Agrawal.
Regarding claim 4, Hirose as modified discloses the air separation unit according to claim 1 (see the combination of references used in the rejection of claim 1 above), further comprising:
a nitrogen gas pipeline configured to draw nitrogen gas from the low-pressure rectification column and extracts nitrogen gas at least via the main heat exchanger (Hirose, Fig. 1, product nitrogen gas drawing pipe 16; Pg. 8, paragraph 131, The product nitrogen gas drawing pipe 16 is a pipe for drawing the product nitrogen gas from the column top portion of the second rectification column 5. The temperature of the product nitrogen gas which has been drawn is in a range of between -192° C. and -175° C., and it may be supplied as nitrogen gas without further treatment, but it may equally be introduced into the main heat exchanger 1 where it may undergo heat exchange with the raw air, whereby the cold may be released therefrom, and said nitrogen gas may be supplied as nitrogen gas at a temperature of between 0° C. and 20° C., for example. In addition, said nitrogen gas may also undergo heat exchange in the sub-cooler 4 before introduction into the main heat exchanger 1);
a nitrogen gas branch pipeline configured to branch the nitrogen gas pipeline downstream from the main heat exchanger, configured to introduce the nitrogen gas from the warm end of the main heat exchanger, configured to draw out nitrogen gas from an intermediate portion, the nitrogen gas then being expanded by the nitrogen turbine and merged into the nitrogen gas pipeline or extracted as nitrogen gas once again via the main heat exchanger (Bauer, Fig. 2, line 9, compressor C, line 9’, line 15, expansion turbine X, line 15’; Pg. 2, paragraph 28-29, In contrast to the procedure shown in FIG. 1, in the procedure shown in FIG. 2, now, at least occasionally, a substream of the compressed nitrogen-rich fraction 9" which was condensed in heat exchanger El is taken off via line 16, expanded in valve f and fed via line 17 to the nitrogen-rich fraction in line 4'. Together with this, the expanded substream is vaporized at least in part, preferably completely, in heat exchanger E1 for the purpose of cold generation. After the nitrogen-rich fraction in compressor C is compressed preferably to a pressure between 20 and 80 bar, in valve f it is preferably expanded to a pressure between 1 and 20 bar. Via line 15, in addition, at least occasionally, a substream of the compressed nitrogen-rich fraction, after cooling thereof in heat exchanger El, can be taken off and cold producingly expanded in expansion turbine X. The expanded substream is subsequently likewise fed to the nitrogen-rich fraction in line 4' via line 15' and warmed in heat exchanger E1 for the purpose of cold generation. By means of this embodiment the additional refrigeration performance is increased);
a nitrogen booster which is provided in the nitrogen gas branch pipeline and configured to boost the pressure of the nitrogen gas to a predetermined pressure (Bauer, Fig. 2, compressor C; Pg. 2, paragraph 28, After the nitrogen-rich fraction in compressor C is compressed preferably to a pressure between 20 and 80 bar).
However, Hirose as modified does not disclose a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster.
Agrawal teaches a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster (Fig. 5, line 30, line 163, line 229, compressor 58, cooler 59).
Hirose as modified fails to teach a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster, however Agrawal teaches that it is a known method in the art of air separation units to include a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster. This is strong evidence that modifying Hirose as modified as claimed would produce predictable results (i.e. increasing the refrigeration capacity available in the main heat exchanger to improve overall system efficiencies). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hirose as modified by Agrawal and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of increasing the refrigeration capacity available in the main heat exchanger to improve overall system efficiencies.
Claims 5 is rejected under 35 U.S.C. 103 as being unpatentable over Hirose as modified by Bauer and Ayres as applied to claim 3 above, and further in view of Darredeau et al. (US Patent No. 5,437,160, hereinafter Darredeau.
Regarding claim 5, Hirose as modified discloses the air separation unit according to claim 3 (see the combination of references used in the rejection of claim 3 above).
However, Hirose as modified does not disclose further comprising a recycling nitrogen line configured to branch from the nitrogen gas branch pipeline inside the main heat exchanger, configured to draw nitrogen gas out from the cold end of the main heat exchanger, and configured to introduce nitrogen gas into the medium-pressure rectification column.
Darredeau teaches a recycling nitrogen line configured to branch from the nitrogen gas branch pipeline inside the main heat exchanger, configured to draw nitrogen gas out from the cold end of the main heat exchanger, and configured to introduce nitrogen gas into the medium-pressure rectification column (See annotated Fig. 4 of Darredeau below, recycling nitrogen line A is depicted to branch from the nitrogen gas branch pipeline B inside the heat exchanger 32, configured to draw nitrogen gas out from the cold end of the main heat exchanger, and configured to introduce nitrogen gas into the medium-pressure column 30).
Hirose as modified fails to teach a recycling nitrogen line configured to branch from the nitrogen gas branch pipeline inside the main heat exchanger, configured to draw nitrogen gas out from the cold end of the main heat exchanger, and configured to introduce nitrogen gas into the medium-pressure rectification column, however Darredeau teaches that it is a known method in the art of air separation units to include a recycling nitrogen line configured to branch from the nitrogen gas branch pipeline inside the main heat exchanger, configured to draw nitrogen gas out from the cold end of the main heat exchanger, and configured to introduce nitrogen gas into the medium-pressure rectification column. This is strong evidence that modifying Hirose as modified as claimed would produce predictable results (i.e. utilizing waste heat of internal process streams to improve overall system efficiencies). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hirose as modified by Darredeau and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of utilizing waste heat of internal process streams to improve overall system efficiencies.
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Annotated Fig. 4 of Darredeau
Claims 6 is rejected under 35 U.S.C. 103 as being unpatentable over Hirose as modified by Bauer and Ayres as applied to claim 3 above, and further in view of Agrawal et al. (US Patent No. 5,255,524), hereinafter Agrawal.
Regarding claim 6, Hirose as modified discloses the air separation unit according to claim 3 (see the combination of references used in the rejection of claim 3 above), further comprising:
a nitrogen booster which is provided in the nitrogen gas branch pipeline and configured to boost the pressure of the nitrogen gas to a predetermined pressure (Bauer, Fig. 2, compressor C; Pg. 2, paragraph 28, After the nitrogen-rich fraction in compressor C is compressed preferably to a pressure between 20 and 80 bar).
However, Hirose as modified does not disclose a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster.
Agrawal teaches a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster (Fig. 5, line 30, line 163, line 229, compressor 58, cooler 59).
Hirose as modified fails to teach a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster, however Agrawal teaches that it is a known method in the art of air separation units to include a second cooling unit configured to cool the nitrogen gas pressure-boosted by the nitrogen booster. This is strong evidence that modifying Hirose as modified as claimed would produce predictable results (i.e. increasing the refrigeration capacity available in the main heat exchanger to improve overall system efficiencies). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hirose as modified by Agrawal and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of increasing the refrigeration capacity available in the main heat exchanger to improve overall system efficiencies.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Miura et al. (JP 2001130928) discloses similar arrangements of boosters, cooling units, and bypass lines for adjusting temperature and pressure parameters of a nitrogen stream of a rectification column.
Agrawal et al. (US Patent No. 4,705,548) discloses a similar nitrogen gas branch line and nitrogen booster.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DEVON T MOORE whose telephone number is 571-272-6555. The examiner can normally be reached M-F, 7:30-5.
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/DEVON MOORE/Examiner, Art Unit 3763 August 06th, 2026
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