DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Examiner Request
The applicant is requested to provide line numbers to each claim in all future claim submissions to aide in examination and communication with the applicant about claim recitations. The applicant is thanked for aiding examination.
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.
Claim(s) 31-35 is/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 pre-AIA the applicant regards as the invention.
In regard to claim 31, the recitation, “the cryogenic expansion turbine has an optimal rotational speed that results in a first optimal efficiency” is indefinite as there is no way to determine what speed the recitation includes and excludes since there are several theoretical efficiencies and there is no way to determine which efficiency is being referenced and no way to determine how or in what way the speed is “optimal”. Optimal is a relative term that has no absolute meaning but is only understood in relative relation to others and in the present recitation there is no way to determine what other speeds and other efficiencies are being compared with the presently recited speed and efficiency and therefore no way to determine what speed and efficiency is being required by the recitation. Further, an analysis of a turbine can lead to several different efficiency definitions (including Hydraulic efficiency, mechanical efficiency, volumetric efficiency, overall efficiency, etc) and there is no way to determine what efficiency is being referenced.
Lastly, it is not clear how the efficiency is permitted to be influenced by operating conditions and therefore it is unclear how the efficiency is to be compared.
For present examination, it is presumed that the turbine has a speed that provides some efficiency that is a highest efficiency as compared with operating the turbine at least some other speeds.
The recitation, “the first booster compressor has an optimal rotational speed that results in a second optimal efficiency” is indefinite as there is no way to determine what speed the recitation includes and excludes since there are several theoretical efficiencies and there is no way to determine which efficiency is being referenced and no way to determine how or in what way the speed is “optimal”. Optimal is a relative term that has no absolute meaning but is only understood in relative relation to others and in the present recitation there is no way to determine what other speeds and other efficiencies are being compared with the presently recited speed and efficiency and therefore no way to determine what speed and efficiency is being required by the recitation. Further, an analysis of a compressor can lead to several different efficiency definitions (including isentropic efficiency, mechanical efficiency, total compressor efficiency, energy efficiency, exergy efficiency, etc) and there is no way to determine what efficiency is being referenced.
Lastly, it is not clear how the efficiency is permitted to be influenced by operating conditions and therefore it is unclear how the efficiency is to be compared.
For present examination, it is presumed that the first booster compressor has a speed that provides some efficiency that is a highest efficiency as compared with operating the first booster compressor at least some other speeds.
The recitation, “the second booster compressor has an optimal rotational speed that results in a third optimal efficiency” is indefinite as there is no way to determine what speed the recitation includes and excludes since there are several theoretical efficiencies and there is no way to determine which efficiency is being referenced and no way to determine how or in what way the speed is “optimal”. Optimal is a relative term that has no absolute meaning but is only understood in relative relation to others and in the present recitation there is no way to determine what other speeds and other efficiencies are being compared with the presently recited speed and efficiency and therefore no way to determine what speed and efficiency is being required by the recitation. Further, an analysis of a compressor can lead to several different efficiency definitions (including isentropic efficiency, mechanical efficiency, total compressor efficiency, energy efficiency, exergy efficiency, etc) and there is no way to determine what efficiency is being referenced.
Lastly, it is not clear how the efficiency is permitted to be influenced by operating conditions and therefore it is unclear how the efficiency is to be compared.
For present examination, it is presumed that the second booster compressor has a speed that provides some efficiency that is a highest efficiency as compared with operating the second booster at least some other speeds.
Claim Interpretation
All of the claims have been evaluated under the three-prong test set forth in MPEP § 2181, subsection I, and it is considered that none of the claim recitations should be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 31-33, 35 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ha (US 2005/0126221) in view of Grainer (US 2012/0174622) and one of Mariotti (CN 102312726) or Wiesmeier (AT 512 651).
In regard to claim 31, Ha teaches a method for separating air by cryogenic distillation (see para. 14 and at least fig. 2), comprising:
(a) compressing an inlet air stream (to 1) in an auxiliary compressor (1) to produce a first compressed air stream (after 1, para. 48);
(b) dividing the first compressed air stream (after 1) into a turbine feed fraction (to 15) and a booster-feed fraction (to 3);
(c) cooling the turbine-feed fraction (12) in a main heat exchanger (5) to form a cooled-turbine-feed fraction (15);
(d) expanding the cooled turbine-feed fraction (15) in a cryogenic expansion turbine (13) having a single wheel to generate work (para. 48, 50), the cryogenic expansion turbine (13) having an inlet temperature lower than -100°C (see T3, para. 48, 55);
(e) compressing the booster-feed fraction (to 3) in a first booster compressor (3) having a single wheel (para. 48, 50), the first booster compressor (3) having an inlet temperature higher than -50°C (see fig. 2 booster compresses air before it is cooled in the main heat exchanger 5);
(f) cooling the booster-feed fraction (after 3) from the first booster compressor (3) in the main heat exchanger (5);
(g) withdrawing the booster-feed fraction (from 3) from an intermediate point (location of 7) of the main heat exchanger (5) and then compressing the booster-feed fraction (from 3) in a second booster compressor (8; para. 48) to form a second booster air stream (9), the second booster compressor (8) having a single wheel (para. 48, 50), the second booster compressor (8) having an inlet temperature lower than -100°C (see T1 para. 48, 55);
(h) further cooling the second booster air stream (9) in the main heat exchanger (5) to produce a liquefied air stream (10; para. 48);
(i) introducing the liquefied air stream (10) into a system of columns (30, 31) for separation therein (para. 48),
Ha does not explicitly teach that a wheel of the turbine, the first booster compressor, and the second booster compressor are all are mounted on a single common rotation shaft so as to rotate at a same rotational speed. However, Ha does teach that the first booster compressor (5) and the second booster compressor (23) are part of an expander booster package (para. 50) and Grainer teaches that it is routine to drive two compressors with a turbine via a single shaft. Grainer teaches mounting a turbine (22), a first booster compressor (14) and a second booster compressor (15) on the same shaft (16)(see figure and para. 33 expander mounted on “the same shaft”). Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify Ha to put the first booster (3), the second booster (8) and turbine (13) on a single shaft for the purpose of driving both boosters with the energy from the turbine and making gainful use of the work provided by the turbine to both boosters in a simple and cost effective manner.
Note that the described modification results in the work generated by the expansion turbine (13) in the step (d) is used to drive both the first booster compressor (3) in the step (e) and the second booster compressor (8) in the step (g).
It is noted that the cryogenic expansion turbine (13) of Ha inherently has an optimal rotational speed (interpreted as a speed for which the turbine has a highest efficiency as compared to at least some other speed) that results in a first optimal efficiency (highest efficiency of 13 as compared with an efficiency at some other speed), the first booster (3) inherently has an optimal rotational speed (interpreted as a speed for which the first booster has a highest efficiency as compared to at least some other speed) that results in a second optimal efficiency (highest efficiency of 3 as compared with an efficiency at some other speed), the second booster compressor (8) has an optimal rotational speed (interpreted as a speed for which the second booster has a highest efficiency as compared to at least some other speed) that results in a third optimal efficiency (highest efficiency of 8 as compared with an efficiency at some other speed).
Ha, as modified, does not explicitly teach operating at least one of the cryogenic expansion turbine (13), the first booster compressor (3), or the second booster compressor (8) at a sub-optimal speed that results in a lower efficiency for the at least one of the cryogenic expansion turbine (13), the first booster compressor (3), or the second booster compressor (8).
However, this is merely operating the system at part load or off-design speeds which is severely routine and ordinary for compressors and turbines. Mariotti teaches that it is known and ordinary for a system having a single shaft (30, 230) connecting a compressor (20, 224) and a turbine (10, 210) having a same speed (para. 10) for the actual practice of operation to require operation at off-design conditions (para. 13-15) and that one can operate guide vanes to attempt to compensate for such off-design conditions (para. 13-15) resulting in other speeds that are not the most efficient design speed, but still provide desired compression by the compressor and expansion by the turbine for the purpose of maintaining operation and obtaining production even if the conditions are not ideal. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to operate Ha at an off-design speed for the purpose of maintaining production of air products for sale in spite of less efficient conditions.
Alternatively to Mariotti, it is well known to operate at part load or off-design speeds as a matter of simplicity and reduction of cost. Wiesmeier teaches that it is known and ordinary for a system having a single shaft (16) connecting a compressor (7) and a turbine (5) having a same speed (page 2 see shaft direct connection) and teaches that one can forgo the cost and complexity of speed controls by simply accepting a lower efficiency (page 3) and operate at other speeds that are not the most efficient design speed when operating with variable conditions for the purpose of maintaining operation and obtaining production during non-ideal conditions. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to operate the system of Ha at non-optimum speeds for the purpose of maintaining production of air products for sale in spite of less efficient conditions.
In regard to claim 32, Ha, as modified above, teaches that the work produced by the turbine (13) is not transferred to a generator, an oil brake, or any compressor other than the first and second booster compressors (3, 8)(see no other compressor, brake or generator taught).
In regard to claim 33, Ha teaches that all of the air compressed in the first booster compressor (3) is subsequently compressed in the second booster compressor (8) (see Fig. 2 without 27 as 27 is optional - para. 56).
In regard to claim 35, Ha teaches that the inlet temperature of the cryogenic expansion turbine (13) is lower than the inlet temperature of the second booster compressor (8) (see fig. 2, para. 48).
Claim(s) 31-33, 35 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ha (US 2005/0126221) in view of Abdelwahab (US 2016/0053764) and one of Mariotti (CN 102312726) or Wiesmeier (AT 512 651).
In regard to claim 31, Ha teaches a method for separating air by cryogenic distillation (see para. 14 and at least fig. 2), comprising:
(a) compressing an inlet air stream (to 1) in an auxiliary compressor (1) to produce a first compressed air stream (after 1, para. 48);
(b) dividing the first compressed air stream (after 1) into a turbine feed fraction (to 15) and a booster-feed fraction (to 3);
(c) cooling the turbine-feed fraction (12) in a main heat exchanger (5) to form a cooled-turbine-feed fraction (15);
(d) expanding the cooled turbine-feed fraction (15) in a cryogenic expansion turbine (13) having a single wheel to generate work (para. 48, 50), the cryogenic expansion turbine (13) having an inlet temperature lower than -100°C (see T3, para. 48, 55);
(e) compressing the booster-feed fraction (to 3) in a first booster compressor (3) having a single wheel (para. 48, 50), the first booster compressor (3) having an inlet temperature higher than -50°C (see fig. 2 booster compresses air before it is cooled in the main heat exchanger 5);
(f) cooling the booster-feed fraction (after 3) from the first booster compressor (3) in the main heat exchanger (5);
(g) withdrawing the booster-feed fraction (from 3) from an intermediate point (location of 7) of the main heat exchanger (5) and then compressing the booster-feed fraction (from 3) in a second booster compressor (8; para. 48) to form a second booster air stream (9), the second booster compressor (8) having a single wheel (para. 48, 50), the second booster compressor (8) having an inlet temperature lower than -100°C (see T1 para. 48, 55);
(h) further cooling the second booster air stream (9) in the main heat exchanger (5) to produce a liquefied air stream (10; para. 48);
(i) introducing the liquefied air stream (10) into a system of columns (30, 31) for separation therein (para. 48).
Ha does not explicitly teach that a wheel of the turbine, the first booster compressor, and the second booster compressor are all are mounted on a single common rotation shaft so as to rotate at a same rotational speed. However, Ha does teach that the first booster compressor (5) and the second booster compressor (23) are part of an expander booster package (para. 50) and Abdelwahab teaches that booster air compressors (BAC, para. 3) are known to have an impeller (para. 10 and to be mounted on a single shaft coupled to a single speed driver (para. 10). Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify Ha to put the first booster (3), the second booster (8) and turbine (13) on a single shaft for the purpose of driving both boosters with the energy from the turbine and making gainful use of the work provided by the turbine to both boosters in a simple and cost effective manner.
Note that the described modification results in the work generated by the expansion turbine (13) in the step (d) is used to drive both the first booster compressor (3) in the step (e) and the second booster compressor (8) in the step (g).
It is noted that the cryogenic expansion turbine (13) of Ha inherently has an optimal rotational speed (interpreted as a speed for which the turbine has a highest efficiency as compared to at least some other speed) that results in a first optimal efficiency (highest efficiency of 13 as compared with an efficiency at some other speed), the first booster (3) inherently has an optimal rotational speed (interpreted as a speed for which the first booster has a highest efficiency as compared to at least some other speed) that results in a second optimal efficiency (highest efficiency of 3 as compared with an efficiency at some other speed), the second booster compressor (8) has an optimal rotational speed (interpreted as a speed for which the second booster has a highest efficiency as compared to at least some other speed) that results in a third optimal efficiency (highest efficiency of 8 as compared with an efficiency at some other speed).
Ha, as modified, does not explicitly teach operating at least one of the cryogenic expansion turbine (13), the first booster compressor (3), or the second booster compressor (8) at a sub-optimal speed that results in a respectively lower efficiency for the at least one of the cryogenic expansion turbine (13), the first booster compressor (3), or the second booster compressor (8).
However, this is merely operating the system at part load or off-design speeds which is severely routine and ordinary for compressors and turbines. Mariotti teaches that it is known and ordinary for a system having a single shaft (30, 230) connecting a compressor (20, 224) and a turbine (10, 210) having a same speed (para. 10) for the actual practice of operation to require operation at off-design conditions (para. 13-15) and that one can operate guide vanes to attempt to compensate for such off-design conditions (para. 13-15) resulting in other speeds that are not the most efficient design speed, but still provide desired compression by the compressor and expansion by the turbine for the purpose of maintaining operation and obtaining production even if the conditions are not ideal. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to operate Ha at an off-design speed for the purpose of maintaining production of air products for sale in spite of less efficient conditions.
Alternatively to Mariotti, it is well known to operate at part load or off-design speeds as a matter of simplicity and reduction of cost. Wiesmeier teaches that it is known and ordinary for a system having a single shaft (16) connecting a compressor (7) and a turbine (5) having a same speed (page 2 see shaft direct connection) and teaches that one can forgo the cost and complexity of speed controls by simply accepting a lower efficiency (page 3) and operate at other speeds that are not the most efficient design speed when operating with variable conditions for the purpose of maintaining operation and obtaining production during non-ideal conditions. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to operate the system of Ha at non-optimum speeds for the purpose of maintaining production of air products for sale in spite of less efficient conditions.
In regard to claim 32, Ha, as modified above, teaches that the work produced by the turbine (13) is not transferred to a generator, an oil brake, or any compressor other than the first and second booster compressors (3, 8)(see no other compressor, brake or generator taught).
In regard to claim 33, Ha teaches that all of the air compressed in the first booster compressor (3) is subsequently compressed in the second booster compressor (8) (see Fig. 2 without 27 as 27 is optional - para. 56).
In regard to claim 35, Ha teaches that the inlet temperature of the cryogenic expansion turbine (13) is lower than the inlet temperature of the second booster compressor (8) (see fig. 2, para. 48).
Response to Arguments
Applicant's arguments filed 11/4/2025 have been fully considered but they are not persuasive in view of the new grounds of rejection above.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOHN F PETTITT whose telephone number is (571)272-0771. The examiner can normally be reached on M-F, 9-5p. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR): http://www.uspto.gov/interviewpractice. The examiner’s supervisor, Frantz Jules can be reached on 571-272-6681. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/JOHN F PETTITT, III/Primary Examiner, Art Unit 3763
JFPIII
January 16, 2026