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 .
Applicant’s Submission of a Response
Applicant’s submission of a response was received on 6/9/2026.
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.
Claim(s) 1-6, 8-11, 14-15 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Burns (US 2024/0116777) in view of Lambert et al. (US 2004/0168965), and Kosick et al. (US 2019/0275536).
Regarding claim 1, Burns teaches a process comprising more than one stage of flotation operated by a first vessel for flotation (primary flotation chamber) configured to receive incoming liquid for treatment, the first vessel generating a first treated liquid and a first foam; wherein the first vessel is associated with a means for hydraulically controlling the incoming liquid into the first vessel; and a means for hydraulically controlling the discharge of first treated liquid from the first vessel; and the first foam is collected in a foam tank (fractionation chamber); (Figs. 1-3, [0057]-[0061], [0168]-[0172], and [0200]-[0204]).
It is noted that Burns teaches that the liquid is delivered to various parts of the equipment by pumping ([0168]-[0172]). While one skilled in the art could conclude that each means is a pump, such a limitation is not explicitly stated so Burns fails to teach all the means for controlling liquid flow being pumps/means that are capable of controlling the hydraulics of vessels independently and a control system controlling with a variable speed drive. Lambert teaches that multiple pumps are used to move liquid from one treatment chamber to another (influent pumped to flocculation tank/first vessel [0012] and clean water pumped (30) from flotation tank/second vessel [0016] and [0020]) that are capable of controlling the hydraulics of vessels independently and a control system controlling with a variable speed drive ([0020]). Thus, one skilled in the art would have found it obvious to provide the variable speed pumps/controller for hydraulically controlling liquid flow during operation consistent with Burns and Lambert in order to allow for control of the liquid within each of the treatment chambers to desired levels during operation.
Burns teaches one primary flotation vessel and the first treated liquid being further treated by downstream means to further remove contaminants. Burns fails to teach a second vessel for flotation configured to receive incoming first treated liquid from the first vessel, the second vessel generating a second treated liquid and a second foam, wherein the second vessel is associated with a means for hydraulically controlling the discharge of second treated liquid from the second vessel; and the second foam is collected in the foam tank. Kosick teaches that flotation chambers can be provided in series thereby increasing removal efficiency as the floatable material in the second flotation chamber would be material that passed through the first flotation chamber and also provide a reduction of reducing the size needed for flotation units thereby saving on the plant footprint, installation, and infrastructure costs ([0058]). As such, one skilled in the art would have found it obvious to provide duplicate flotation vessels in series in order to better remove contaminants while providing economic benefits.
Regarding claim 2, Burns teaches that flow can be controlled via automated valves to and from the various treatment chambers ([0168]-[0172]). As discussed above, providing duplicate flotation vessels in series as claimed would have been an obvious matter to one skilled in the art based on Burns in view of Kosick.
Regarding claim 3, Burns fails to teach the flotation vessels include a break tank that collects the second treated liquid. Kosick teaches that the flotation vessel can include a tank/vessel after the flotation step capable of receiving incoming liquid from the flotation vessel upstream of it (Figs. 2-3). As such, one skilled in the art would have found it obvious to provide break tank as claimed as part of the flotation vessels in order to receive the incoming treated liquid and prepare said fluid for more downstream treatments.
Regarding claim 4, Burns teaches that at two primary flotation vessels are operated in parallel ([0169]-[0175]).
Regarding claims 5-6 and 8, Burns only teaches one foam tank and thus does not teach a second foam tank with accompanying operations. It is Examiner’s position that providing a foam tank for each of the foam collected from each flotation process would have been an obvious matter of duplicating essential working parts especially in light of Kosick teaching duplication of flotation vessels (see In re Harza, 274 F.2d 669, 124 USPQ 378 (CCPA 1960) (Claims at issue were directed to a water-tight masonry structure wherein a water seal of flexible material fills the joints which form between adjacent pours of concrete. The claimed water seal has a "web" which lies in the joint, and a plurality of "ribs" projecting outwardly from each side of the web into one of the adjacent concrete slabs. The prior art disclosed a flexible water stop for preventing passage of water between masses of concrete in the shape of a plus sign (+). Although the reference did not disclose a plurality of ribs, the court held that mere duplication of parts has no patentable significance unless a new and unexpected result is produced.).
Regarding claim 9, Burns teaches that the foam may be sent to disposal with no further treatment ([0215]).
Regarding claims 10 and 14, Burns teaches that the foam portion can be sent for further treatment in a fourth foam vessel (re-flotation chamber) (Figs. 1-3, [0057]-[0061], [0168]-[0172], and [0200]-[0204]).
Regarding claim 11, Burns teaches that the vessels/tanks includes a foam fractionator including a hood ([0183]-[0185]).
Regarding claim 15, see claim 5 above for the second foam tank and claim 14 above for the fourth foam vessel.
Regarding claim 20, the liquid produced from the Burns treatment process reads on the claim.
Claim(s) 7 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Burns (US 2024/0116777) in view of Lambert et al. (US 2004/0168965), and Kosick et al. (US 2019/0275536) as applied above, and further in view of Kin et al. (US 2005/0126972).
Regarding claim 7, Burns fails to teach mixing the contents of the second foam tank with the incoming liquid for treatment in the first vessel. Kin teaches that foams produced from treating water can be fractionated/destroyed and then combined with the incoming liquid to be treated thereby further treating the liquid content of the second foam ([0014] and claim 4). As such, one skilled in the art would have found it obvious to combine the liquid from the second foam tank with the incoming liquid stream in order to further treat the liquid in the foam.
Regarding claim 12, Burns teaches the fractionator including a hood and thus fails to teach the fractionator being hoodless. Kin teaches that in fractionating/destroying the foam, a centrifugal type degassing unit (considered to be hoodless) can be employed ([0014] and claim 4). As such, one skilled in the art would have found it obvious to use other known foam fractionator, such as a hoodless one, with a reasonable expectation of success in view of Kin.
Claim(s) 16-17, and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Burns (US 2024/0116777) in view of Puttamraju et al. (US 11,840,471), Lambert et al. (US 2004/0168965), and Kosick et al. (US 2019/0275536).
Regarding claims 16-17, Burns teaches a flotation process comprising more than one stage of flotation for the removal of PFAS from wastewater, one or more first vessels for flotation configured to receive incoming liquid for treatment, the first vessel generating a first treated liquid and a first foam comprising long chain PFAS (Figs. 1-3, [0057]-[0061], [0163]-[0172], and [0200]-[0209]).
Burns fails to teach one or more second vessels for flotation configured to receive incoming first treated liquid from the first vessel for treatment, the second vessel generating a second treated liquid and a second foam. Burns teaches one primary flotation vessel and the first treated liquid being further treated by downstream means to further remove contaminants. Burns fails to teach a second vessel for flotation configured to receive incoming first treated liquid from the first vessel, the second vessel generating a second treated liquid and a second foam, wherein the second vessel is associated with a means for hydraulically controlling the discharge of second treated liquid from the second vessel; and the second foam is collected in the foam tank. Kosick teaches that flotation chambers can be provided in series thereby increasing removal efficiency as the floatable material in the second flotation chamber would be material that passed through the first flotation chamber and also provide a reduction of reducing the size needed for flotation units thereby saving on the plant footprint, installation, and infrastructure costs ([0058]). As such, one skilled in the art would have found it obvious to provide duplicate flotation vessels in series in order to better remove contaminants while providing economic benefits.
Burns teaches that short chain PFAS are removed by a different process as froth flotation, which Burns teaches is done without any flocculant, does not sufficiently remove short chain PFAS. Burns fails to teach that a flocculant is added to the second vessel to assist in the removal of short chain PFAS. Puttamraju teaches that specifically to remove short chain PFAS compounds, it is beneficial to add polyDADMAC in flotation processes (Fig. 6A and C9/L24-10/8). As Burns teaches that long chain PFAS are removed via flotation and then are process in downstream means to remove short chain PFAS,it would have been obvious to provide polyDADMAC as a flocculant as claimed in second froth flotation means as taught in Puttamraju in order to aid in the removal of short chain PFAS in place of the adsorption means taught in Burns as Puttamraju teaches that flotation with the use of specific flocculants are effective in removing short chain PFAS and one skilled in the art would have a reasonable expectation of success in doing so. It is noted that first flotation vessel would be the one taught in Burns and the next flotation in series that would be added based on Puttamraju and Kosick would be the one with the flocculant added to specifically remove the short chain PFAS contaminants.
It is noted that Burns teaches that the liquid is delivered to various parts of the equipment by pumping ([0168]-[0172]). While one skilled in the art could conclude that each means is a pump, such a limitation is not explicitly stated so Burns fails to teach all the means for controlling liquid flow being pumps/means that are capable of controlling the hydraulics of vessels independently and a control system controlling with a variable speed drive. Lambert teaches that multiple pumps are used to move liquid from one treatment chamber to another (influent pumped to flocculation tank/first vessel [0012] and clean water pumped (30) from flotation tank/second vessel [0016] and [0020]) that are capable of controlling the hydraulics of vessels independently and a control system controlling with a variable speed drive ([0020]). Thus, one skilled in the art would have found it obvious to provide the variable speed pumps/controller for hydraulically controlling liquid flow during operation consistent with Burns and Lambert in order to allow for control of the liquid within each of the treatment chambers to desired levels during operation.
It is noted modified Burns teaches the claimed method steps and also the broad result of removing PFAS. The specific type of PFAS removed (long or short chain) would be a result of the claimed process steps. As the claimed process steps are taught in modified Burns, the expected results would also be similar even if not explicitly stated.
Regarding claim 19, see claim 3 above.
Response to Arguments
Applicant's arguments filed 6/9/2026 have been fully considered but they are not persuasive.
Applicant argues that the combination of prior fails to teach a stagewise flotation process where each flotation vessel is hydraulically controllable through a controller and variable speed pumps. Attention is directed to claims 1 and 16 above where flotation processes are well known for removing various contaminants such as PFAS (Burns and Puttamraju), flotation vessels in series are known and used for specific purposes (Kosick), and controlling the level of various tanks/flotation vessels (Burns and Lambert) and flow within the system are done by a variety of means that include control systems and variable speed pumps (Lambert). Thus, the combination claimed is merely a combination of well known and used means in the art. Level heights in tanks would be controlled in order to ensure proper residence/retention times (Burns [0194]). Hydraulically controlling the level in the tank would be needed in order to ensure the desired level would be accomplished via known means, such as pumps and valves, and Lambert specifically teaches using a controller that operates variable speed pumps hydraulically control the level in the flotation tanks to ensure proper treatment and operation in the flotation vessels. As such, the combination teaches all claimed method steps.
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).
Similarly, the arguments directed to claim 16 are similarly rebutted by the combination of prior references above. Puttamraju explicitly teaches that flotation processes with specific flocculants allow for treatment and removal of short chain PFAS, something that Burns teaches is done by a different means. As discussed above, one skilled in the art would have found it obvious to provide or include the short chain removal means in combination with or instead of the means taught in Burns with a reasonable expectation of success.
Allowable Subject Matter
Claim 21 is allowed.
It is Examiner’s position that the amount of modification necessary for Burns to read on claim 21 would be the result of impermissible hindsight due the number of references and/or modifications needed to address every limitation present in claim 21.
Conclusion
THIS ACTION IS MADE FINAL. 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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/PETER KEYWORTH/Primary Examiner, Art Unit 1776
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