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 .
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.
Claims 1 – 4 are rejected under 35 U.S.C. 103 as being unpatentable over JP 2018-168274 to Iijima (hereinafter referred to as Iijima) in view of KR 10-1187004 to Kim et al. (hereinafter referred to as Kim ‘004) and KR 10-2015-0006718 to Kim et al. (hereinafter referred to as Kim ‘718).
In regard to claims 1 – 3, as discussed in paragraphs [0012] and [0015] – [0017], Iijima discloses a method that performs methane fermentation for organic residue and results in a biogas having methane and carbon dioxide. As further discussed in paragraphs [0020] – [0021], the mixed biogas containing methane and carbon dioxide is supplied to a culture tank containing water as a culture solution for culturing algae. Culturing the algae fixes the carbon dioxide contained in the mixed gas to the algae and results in a biogas stream with a higher methane concentration. Iijima does not disclose a step of re-supplying to the culture tank or another culture tank the mixed gas that has passed through the culture solution to reduce the carbon dioxide contained in the mixed gas. Firstly, it is noted that in Iijima the culture tank is functioning as a separator that removes carbon dioxide from the biogas stream. It is known in the art to use separators in series to achieved higher separation rates. As discussed in the abstract and shown in figure 2, Kim ‘004 discloses a system for absorb carbon dioxide from biogas to similarly result in a biogas with a higher methane concentration. The system uses absorption columns (10, 20, 30) in series. The later columns allow for more carbon dioxide to be removed to achieve the higher methane concentration. The culture tank in Iijima acts similarly to the absorption column in Kim ‘004 to capture carbon dioxide. Predictably, further culture tanks provide in series would allow more carbon dioxide to be captures and similarly result in a biogas with a higher methane concentration.
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Iijima to include a plurality of culture tanks in series as suggested by Kim ‘004 in order to produce a biogas with a higher methane concentration. In this case, the mixed gas that has passed through the first culture solution in the first culture tank is supplied to a second culture solution in a second culture tank, and the re-supplying in performed in the second culture tank.
Alternately, one of ordinary skill in the art would reasonably expect the algae in a single tank could further consume carbon dioxide. For example, Kim ‘718 discloses an algae cultivation facility that supplies carbon dioxide form a cylinder (41) and also collects the effluent gas a port (12) and uses a pump (31) to resupply the carbon dioxide in the effluent gas back to the algae culture solution. Predictably, the more of the carbon dioxide the algae consume, the lower the concentration of carbon dioxide can remain in a biogas collected from the tank containing the algae culture.
Thus, it alternately would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Iijima and Kim ‘004 to re-supply the mixed gas from the culture tank back to the same culture tank as suggested by Kim ‘718 as it is known that the algae can continue to consume carbon dioxide and this arrangement would function equivalently to reduce the carbon dioxide concentration in the biogas such that it has a higher methane concentration.
Additionally, as discussed in paragraph [0018] of Iijima, it is known to use the digestate produced in performing methane fermentation as nutrients for the algae. As discussed above, Iijima does not disclose the re-supplying step. The combination of Iijima and Kim ‘004 and Kim ‘718 includes a re-supplying step where the mixed gas is supplied back to the culture tank or to another culture tank. The algae in the re-supplying step is the same and predictably would also benefit from the nutrients in the digestate. Thus, it would further have been obvious to one of ordinary skill in the art to modify the combination of Iijima and Kim ‘004 and Kim ‘718 to also supply digestate produced in the methane fermentation to the culture tank or another culture tank in the re-supplying step in order to similarly provide the algae in this step with nutrients.
In regard to claim 4, Iijima is used as the primary reference. As discussed in paragraph [0018], Iijima includes an inorganic substance (i.e. nitrogen and phosphorous) contained in residue produced in performing the methane fermentation. The inorganic substance is supplied to the culture tank and/or another one of the culture tanks, as it is a suitable nutrient for the algae.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Iijima and Kim ‘004 and Kim’718 as applied to claims 1 – 4 above, and further in view of JP 2021-151640 to Nomura (hereinafter referred to as Nomura).
The combination of Iijima and Kim ‘004 and Kim ‘718 is discussed above in section 5. Iijima is used as the primary reference disclosing the step of performing methane fermentation. Iijima does not disclose using the cultured algae as the organic residue for the methane fermentation. Nomura also discloses a process with a methane fermentation tank (1). As discussed in paragraph [0029], Nomura also uses a water rich in carbon dioxide to grow algae in a tank. The algae is disclosed to be capable of being reused as a raw material for methane fermentation.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Iijima and Kim ‘004 and Kim ‘718 to use the cultured algae as the organic residue for methane fermentation as suggested by Nomura as this is a known material in the art that can be used to perform methane fermentation.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Iijima and Kim ‘004 and Kim’718 as applied to claims 1 – 4 above, and further in view of JP 2011-241182 to Kameyama et al. (hereinafter referred to as Kameyama).
The combination of Iijima and Kim ‘004 and Kim ‘718 is discussed above in section 5. None of these reference disclose collecting the culture solution and using flash distillation to separate methane form the culture solution. Kameyama is directed to a process that results in a gas that is mainly methane and water, with hydrogen, carbon dioxide, and carbon monoxide as additional components, as discussed in paragraph [0011]. As further discussed, the water can be removed in a flash distillation tower. Predictably, an organic material in the water would remain with the water as the more volatile methane vaporizes. Thus, one of ordinary skill in the art would reasonably expect flash distillation to be usable for separating methane from a culture solution having water and algae.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Iijima and Kim ‘004 and Kim ‘718 to collect the culture solution before it is discarded and to use flash distillation to separate methane from the culture solution as suggested by Kameyama in order to collect any of the methane remaining in the culture solution.
Response to Arguments
Applicant's arguments filed December 29, 2025 have been fully considered but they are not persuasive.
Applicant argues that Iijima, Kim ‘004, and Kim ‘718 fail to teach or suggest limitation “in re-supplying the mixed gas, for culturing the algae, digestate produced in performing methane fermentation is supplied to the culture tank or the another culture tank as nutrients for the algae”. As applicant acknowledges, Iijima discloses using the digestate from the methane fermentation as nutrients for the algae. Applicant argues that Iijima does not suggest using the digestate in a step of re-supplying the mixed gas. Kim ‘004 and Kim ‘718 are used as secondary references suggesting the re-supplying step in order to further purify the methane. The examiner agrees that Kim ‘004 and Kim ‘718 are not directed to methane separation using an algae culture and thus do not teach supplying the culture tank or the another culture tank with digestate from methane fermentation in the re-supplying step. These arguments, however, are considered to be against the references individually. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). In the combination, Kim ‘004 and Kim ‘718 are used to suggest the principle of providing a re-supply back to the culture tank to another culture tank as a known means in separation processes to produce a further purified methane product. In this case, the algae in the re-supplying step is the same and predictably would also benefit from the nutrients in the digestate. Therefore, the examiner considers it to have been obvious to one of ordinary skill in the art to modify the combination of Iijima and Kim ‘004 and Kim ‘718 to also supply digestate produced in the methane fermentation to the culture tank or another culture tank in the re-supplying step in order to similarly provide the algae in this step with nutrients.
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.
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/ROBERT CLEMENTE/Primary Examiner, Art Unit 1773
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