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 .
Response to Amendments
This is a final office action in response to applicant's arguments and remarks filed on
01/09/2026.
Status of Rejections
The rejection of claim 10 under 35 USC 112(b) is withdrawn in view of the Applicant’s amendments.
The previous prior art rejections are withdrawn in view of the Applicant’s amendments.
New grounds of art rejection are necessitated by the Applicant’s amendments.
Claims 1-18 are pending and under consideration for this Office Action.
Claim Rejections - 35 USC § 102
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1, 2, 7, 8, 14, and 18 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Domon et al (US 20180195183 A1).
Claim 1: Domon discloses a method for operating an electrolysis system (see e.g. abstract) comprising an electrolyzer for generating oxygen and hydrogen (see e.g. [0011] and [0016]) as first and second product gas streams respectively (see e.g. #7 and #10 on Fig 4), the method comprising:
discharging the first product gas stream from the electrolyzer (see e.g. #7 on Fig 4, [0040]),
receiving the first product gas stream in a first gas separation device (see e.g. #6 on Fig 4), separating a liquid from the first product gas stream in the first gas separation device to form a dried first product gas stream (see e.g. [0050]: “The anode side gas-liquid separation unit 6 separates the electrolytic solution and the anode gas conveyed from the anode chamber 2 from each other”), and discharging the dried first product gas stream from the first gas separation device via a first discharge line (see e.g. #102 on Fig 4), and
mixing a secondary gas with the first product gas stream at a location upstream of the first discharge line (see e.g. #12 on Fig 4), wherein the secondary gas is a gas which is generated by the electrolyzer or is an inert gas (see e.g. #20 on Fig 4; [0068]: “Anode gas (oxygen gas) discharged from the anode side gas-liquid separation unit 6 and flowing in the anode gas feeding line 20 is divided into the anode gas feeding line 20 and the anode gas release line 102 at the above-described branch. A part of the oxygen gas is supplied to the circulation tank 12 through the anode gas feeding line 20”).
Claim 2: Domon discloses that the secondary gas comprises the dried first product gas stream (see e.g. [0068]: “Anode gas (oxygen gas) discharged from the anode side gas-liquid separation unit 6 and flowing in the anode gas feeding line 20 is divided into the anode gas feeding line 20 and the anode gas release line 102 at the above-described branch. A part of the oxygen gas is supplied to the circulation tank 12 through the anode gas feeding line 20”).
Claim 7: Domon discloses that at least part of a dried product gas is branched off and temporarily stored in a gas store (see e.g. #20 and 21 on Fig 4), wherein the stored product gas is recycled as secondary gas when the electrolysis system is started up (see e.g. [0014]).
Claim 8: Domon discloses an electrolysis system (see e.g. Fig 4) comprising:
an electrolyzer (see e.g. #5 on Fig 4) for generating oxygen and hydrogen (see e.g. [0011] and [0016]) as first and second product gas streams respectively (see e.g. #7 and #10 on Fig 4),
a first product gas line and a second product gas line for discharging the first product gas stream and the second product gas stream respectively from the electrolyzer (see e.g. [0040] and [0041]);
a first gas separation device configured to receive the first product gas stream from the first product gas line, to separate liquid from the first product gas stream, and to discharge a dried first product gas stream via a first discharge line (see e.g. [0049] and [0068]), and
a secondary gas line, by which a secondary gas is to be mixed with the first product gas stream at a location upstream of the first discharge line (see e.g. #20 and #22 on Fig 4), wherein the secondary gas line is configured to receive a gas that is generated by the electrolyzer as the secondary qas (see e.g. #20 on Fig 4).
Claim 14: Domon discloses that the secondary gas line is fluidically connected to a gas store for the secondary gas (see e.g. #22 on Fig 4).
Claim 18: Domon discloses that the dried first product gas is injected into the first product gas stream at a location that is upstream of the first gas separation device (see e.g. #22 on Fig 4).
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 5, 9, 10, and 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Domon.
Claim 5: Domon discloses a pressure of the secondary gas prior to being injected is greater than a pressure in the first gas separation device (see e.g. [0064]).
Domon does not explicitly teach that the secondary gas is injected into the first gas separation device and mixed with the first product gas stream therein. Domon teaches that the secondary gas is injected into a second gas separation device and mixed with the first product gas stream therein (see e.g. #22, #102, and #23 on Fig 4). The point where the secondary gas is added to the first product gas stream is considered an arbitrary distinction along path #102 (see e.g. Fig 4) that would result in the same type of gas stream entering #23. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify the method of Domon so that the secondary gas is injected into the first gas separation device and mixed with the first product gas stream therein as a matter of design choice.
Claim 9: Domon does not explicitly teach that a downstream end of the secondary gas line opens into the first gas separation device. Domon teaches that the secondary gas is injected into a second gas separation device and mixed with the first product gas stream therein (see e.g. #22, #102, and #23 on Fig 4). The point where the secondary gas is added to the first product gas stream is considered an arbitrary distinction along path #102 (see e.g. Fig 4) that would result in the same type of gas stream entering #23. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify the method of Domon so that the secondary gas is injected into the first gas separation device and mixed with the first product gas stream therein as a matter of design choice.
Claim 10: Domon discloses that an upstream end of the secondary gas line is branched off from the first discharge line (see e.g. #20 on Fig 4).
Claim 15: Domon does not explicitly teach that the secondary gas is injected into the first gas separation device and mixed with the first product gas stream therein. Domon teaches that the secondary gas is injected into a second gas separation device and mixed with the first product gas stream therein (see e.g. #22, #102, and #23 on Fig 4). The point where the secondary gas is added to the first product gas stream is considered an arbitrary distinction along path #102 (see e.g. Fig 4) that would result in the same type of gas stream entering #23. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify the method of Domon so that the secondary gas is injected into the first gas separation device and mixed with the first product gas stream therein as a matter of design choice.
Claim(s) 3 and 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Domon in view of Seymour et al (US 20210020975 A1).
Claim 3: Domon discloses that the secondary gas is is the gas which is generated in the electrolysis system and wherein the secondary gas is recycled (see e.g. [0068]: “Anode gas (oxygen gas) discharged from the anode side gas-liquid separation unit 6 and flowing in the anode gas feeding line 20 is divided into the anode gas feeding line 20 and the anode gas release line 102 at the above-described branch. A part of the oxygen gas is supplied to the circulation tank 12 through the anode gas feeding line 20”).
Domon does not explicitly teach that the secondary gas is purified. Domon teaches that secondary gas is taken from one of the product gas streams (see e.g. [0031] and [0040]). Seymour teaches that these electrolytic systems can include product gas processing including purifying, drying, compressing, and cooling (see e.g. [0361]). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify the method of Domon by including the step of purifying the gas as taught in Seymour because this is a known processing step for oxygen gas produced via electrolysis of water. Purifying the gas would remove any unwanted by-products from the secondary gas stream.
Claim 4: Domon in view of Seymore teaches that at least part of the product gas stream is sent to a gas separation device and used as secondary gas (see e.g. Domon - [0068]).
Domon in view of Seymore does not explicitly teach that the gas stream is purified after the gas separation device. However, this purification step can only occur in a limited number of places between the generation of the product gas streams and the mixing of the secondary gas stream with one of the product streams. Furthermore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention that the effect of purifying would not drastically change based on its location in process. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to have the gas stream purified after the gas separation device as a simple design choice with a reasonable expectation of success.
Claim(s) 6 and 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Domon in view of Rusta-Sallehy et al (US 20050186458 A1).
Claim 6: Domon does not explicitly teach a foreign gas concentration in the first product gas stream which is mixed with the secondary gas is determined but does teach the secondary gas is mixed in to reduce the concentration of a foreign gas (see e.g. [0068]). Rusta-Sallehy discloses a method of electrolyzing water (see e.g. abstract) wherein a foreign gas concentration (hydrogen) in the product gas stream (oxygen) is determined to ensure a safe concentration of hydrogen is maintained (see e.g. [0080]). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify method of Domon to include the step of determining a foreign gas concentration in the product gas stream to make sure a safe level of foreign gas is in the product gas stream.
Claim 13: Domon does not explicitly teach a measuring device for measuring a foreign gas concentration in the product gas stream which is mixed with the secondary gas. Rusta-Sallehy discloses a method of electrolyzing water (see e.g. abstract) wherein a foreign gas concentration (hydrogen) in the product gas stream (oxygen) is determined to ensure a safe concentration of hydrogen is maintained (see e.g. [0080]). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify system of Domon to include a measuring device for measuring a foreign gas concentration in the product gas stream to make sure a safe level of foreign gas is in the product gas stream.
Additionally, Domon discloses using a pump to control the flow rate of the secondary gas (see e.g. [0064]). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify system of Domon in view of Rusta-Sallehy to control the volumetric flow rate of the secondary gas is adjusted depending on the foreign gas concentration to make sure a safe level of foreign gas is maintained.
Claim(s) 11 and 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Domon in view of Libby et al (US 20070000789 A1).
Claim 11: Domon does not explicitly teach a recombiner is arranged in the first discharge line between the first gas separation device and the upstream end of the secondary gas line. Libby teaches including a recombiner downstream from the electrolytic cell that can remove unwanted gas crossover from the product stream by reacting the two gases together into water (see e.g. [0020]). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify system of Domon to include a recombiner taught in Libby arranged in the first discharge line between the first gas separation device and the upstream end of the secondary gas line to remove unwanted gas crossover from the product stream by reacting the two gases together into water.
Claim 16: Domon does not explicitly teach that the dried first product gas stream is passed through a recombiner to further purify the dried first product gas stream. Libby teaches including a recombiner downstream from the electrolytic cell that can remove unwanted gas crossover from the product stream by reacting the two gases together into water (see e.g. [0020]). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify system of Domon to include a recombiner taught in Libby to treat the dried first product gas stream to remove unwanted gas crossover from the product stream by reacting the two gases together into water.
Based on the above configuration, the secondary gas would comprise a portion of the dried first product gas stream that has been purified in the recombiner for Domon in view of Libby.
Claim(s) 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Domon in view of Kurokawa et al (US 20170044677 A1).
Claim 12: Domon does not explicitly teach that the secondary gas line comprises a fan. However, Domon teaches that the secondary gas line is included to reduce the concentration of hydrogen (see e.g. abstract). Kurokawa teaches an electrolytic hydrogen gas generator (see e.g. abstract) wherein the means to dilute the hydrogen gas includes a fan (see e.g. [0034]). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify system of Domon by including a fan in the secondary gas line to aid in the diluting of hydrogen and provide a means of moving the secondary gas.
The fan of Domon in view of Kurokawa is configured to increase a pressure of the secondary gas (see e.g. [0034]). It would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention that this pressure would be above a pressure in the first gas separation device so that the streams can be mixed. If the pressures were reversed, the second gas cannot enter the device.
Claim(s) 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Domon in view of Libby as applied to claim 16 above, and in further view of Sandeep et al (“Experimental investigation on the kinetics of catalytic recombination of hydrogen with oxygen in air”, International Journal of Hydrogen Energy, Volume 39, Issue 31, 22 October 2014, Pages 17906-17912).
Claim 17: Domon in view of Libby does not explicitly teach heating the dried first product gas stream to at least 80oC before passing the dried first product gas stream through the recombiner. Sandeep investigated the effects of different variables on catalytic recombination of hydrogen with oxygen (see e.g. abstract). According to Sandeep, “It is observed that up to a temperature of about 110oC, the overall rate constant rises exponentially according to Arrhenius equation. Nearly above 110 oC, the rate of increase of the apparent rate constant with temperature decreases. In this region, the internal diffusion of hydrogen inside catalyst particle may be limiting the overall rate of reaction. Above temperature of 280 oC, the plot is tending towards a plateau, indicating the predominance of external mass transfer limitations on the overall kinetics at higher temperatures. The external mass transfer coefficient increases nearly linearly with temperature according to the correlations used. In this region, the intrinsic surface reaction is so fast that the rate determining step becomes the external mass transfer of hydrogen from bulk fluid to the catalyst surface.” (see e.g. page 17911, “Effect of temperature”). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant invention to modify the method of Domon in view of Libby so that the dried first product gas stream is heated to at least 110oC before passing the dried first product gas stream through the recombine to improve the overall rate constant.
Response to Arguments
Applicant’s arguments filed 01/09/2029 with respect to prior art rejections from the previous Office Action. have been fully considered and are persuasive. These art rejections have been withdrawn.
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 ALEXANDER W KEELING whose telephone number is (571)272-9961. The examiner can normally be reached 7:30 AM - 4:00 PM. 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) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Luan Van can be reached at 571-272-8521. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ALEXANDER W KEELING/Primary Examiner, Art Unit 1795
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