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 (JP2022-032755, filed on March 03, 2022) under 35 U.S.C. 119 (a)-(d). Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Claim Objections
Claim 3 objected to because of the following informalities:
The phrase “supplied to other second desalting device” should be corrected to read “supplied to the other second desalting device” for grammar.
Appropriate correction is required.
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.
Claims 4 is 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 4 recites the limitation “a dissolved salt concentration less than a saturation solubility.” It is generally unclear as to what quantities are being compared. The instant SPEC defines saturation solubility as the solubility product Ksp of a scale species XY, expressed by the relationship [X⁺][Y⁻] = Ksp, where [X⁺] and [Y⁻] are molar ion concentrations (¶[0045]). The SPEC does not explain how the claimed dissolved salt concentration is compared with this ion-concentration product, leaving the scope of the limitation indefinite.
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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
Determining the scope and contents of the prior art.
Ascertaining the differences between the prior art and the claims at issue.
Resolving the level of ordinary skill in the pertinent art.
Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-7 are rejected under 35 U.S.C. 103 as being unpatentable over NAKAMURA et al. (JP2021037480A, hereinafter, NAKAMURA).
Regarding Claim 1, NAKAMURA discloses water treatment systems and methods using reverse osmosis (RO) membranes and permeate water to clean scale from membrane surfaces (¶[0001]–¶[0002]). FIG. 1 illustrates water treatment system 1A with RO membrane device A and parallel downstream devices B and C. Pump P1 supplies raw water under pressure from tank 51 through line 55 to A’s supply side As. A’s concentrate side Ac connects to B’s supply side Bs through line AB1 and C’s supply side Cs through line AC2. A’s permeate side At connects to C’s supply side Cs through line AC1 and B’s supply side Bs through line AB2. Gate valves V1–V4 in lines AB1, AC1, AB2, and AC2, respectively, switch the concentrate and permeate supplies between B and C (¶[0011]–¶[0014]). Based on the illustrated arrangement, device A corresponds to the first desalting device, and devices B and C correspond to second desalting devices arranged in parallel.
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FIG. 1 of NAKAMURA
In operation, parallel devices B and C alternate between concentrate treatment and permeate-water cleaning. Switching from the first to the second connection arrangement sends A’s permeate through line AB2 to B, gradually dissolving scale that accumulated on B’s membrane surface during concentrate treatment. At the same time, C receives A’s concentrate for further desalting, during which scaling progresses in C. After a certain period, the connections are switched back, sending A’s concentrate to B’s supply side Bs and A’s permeate to C’s supply side Cs. The cleaned device B resumes concentrate treatment while the permeate gradually dissolves scale from C’s membrane surface and cleans C. Repeated switching allows B and C to exchange treatment and cleaning roles, removing scale in a timely manner using RO permeate (¶[0016]–¶[0017]).
Based on the disclosure, it is reasonable to interpret the RO permeate produced by device A as “a dilute water having a lower concentration than the first concentrated water.” Device A separates the feed water into concentrate and low-TDS permeate, and the switching arrangement directs this lower-salt permeate to B or C in place of A’s concentrate to dissolve scale on the receiving device’s membrane surface and clean that device.
In the first connection arrangement, pump P1 supplies raw water from tank 51 to first-stage device A, which separates the feed into concentrate and permeate. A’s concentrate flows through line AB1 to second-stage device B for further desalting. This treatment produces concentrate and permeate that leave B through sides Bc and Bt, respectively (¶[0023]–¶[0024]).
A control unit can automatically operate the gate valves that direct concentrate and permeate to B and C. Solenoid valves are preferred for their operating speed. A timer sets the opening and closing times, and the control unit operates the valves when those preset times are reached. To protect the RO membranes from sudden pressure fluctuations, the valves are opened and closed slowly. To further limit these fluctuations, pumps P1 and P2 can be controlled by inverters. The inverter settings are temporarily lowered before valve switching to reduce pressure and flow, then restored afterward (¶[0044]).
The cleaning method is effective in preventing membrane scaling. During RO treatment, poorly soluble components in raw water accumulate or precipitate on membrane surfaces, forming scale that degrades membrane performance. Scaling is not limited to a particular substance. Examples include calcium, magnesium, barium, and aluminum salts, as well as silica (¶[0064]).
In view of the preset timer control and the disclosed purpose of preventing scale-related performance loss, a person skilled in the art would set the switching time so that dilute-water cleaning begins “before a corrected permeated water amount of the second desalting device is reduced.” Beginning the cleaning operation at that time would be reasonably expected to dissolve scale as it develops and maintain membrane performance using the existing switching arrangement.
Regarding Claim 2, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. NAKAMURA discloses the second-stage devices B and C arranged in parallel downstream of the first-stage device A (¶[0011]–¶[0014]). While device A treats the feed water, device B treats device A’s concentrate in normal operation and device C receives device A’s permeate for membrane cleaning. Switching the connections sends device A’s concentrate to device C for treatment and device A’s permeate to device B for cleaning (¶[0016]–¶[0017]).
Regarding Claim 3, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. NAKAMURA discloses the second-stage devices B and C arranged in parallel downstream of the first-stage device A (¶[0011]–¶[0014]). While device A treats the feed water, device B treats device A’s concentrate in normal operation and device C receives device A’s permeate for membrane cleaning. Switching the connections sends device A’s concentrate to device C for treatment and device A’s permeate to device B for cleaning (¶[0016]–¶[0017]). The control unit opens and closes the gate valves at the times preset using the timer (¶[0044]). In Example 1, the connections are switched after 200 hours of operation to supply device A’s permeate to device B for cleaning. After another 200 hours, the connections are switched back, and device B’s permeate output is compared with its initial output (¶[0065]).
Regarding the limitation “switched at a frequency of once every 30 to 180 minutes,” the switching interval is a result-effective variable affecting scale buildup during concentrate treatment and the time available for permeate-water cleaning. NAKAMURA’s timer allows that interval to be preset and adjusted. A person skilled in the art would optimize the switching interval through routine experimentation using the preset timer to shorten concentrate treatment, limit scale accumulation, and allow sufficient cleaning to maintain membrane performance. Selecting a workable interval within the claimed 30–180-minute range would constitute routine optimization of the disclosed operating conditions (In re Aller, 220 F.2d 454, 456–57; 1955).
Regarding Claim 4, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. NAKAMURA discloses that the permeate from the first-stage RO membrane device A is supplied to second-stage devices B or C to gradually dissolve scale accumulated on the membrane surface and clean the device (¶[0016]–¶[0017]). Based on the disclosure, Device A’s permeate corresponds to “dilute water,” as the permeate is undersaturated with respect to the scale-forming salt and dissolves the scale during cleaning.
Regarding Claim 5, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. NAKAMURA discloses that the permeate from the first-stage RO membrane device A is supplied to second-stage devices B or C to gradually dissolve scale accumulated on the membrane surface and clean the device (¶[0016]–¶[0017]).
Regarding Claim 6, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. NAKAMURA discloses adding acidic or alkaline pH adjusters to the permeate from the first-stage RO membrane device A (¶[0056]). Hydrochloric acid or sulfuric acid increases calcium solubility when calcium carbonate scale is present, while sodium hydroxide increases silica solubility. These pH adjustments improve RO membrane cleaning efficiency (¶[0058]).
Regarding Claim 7, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. NAKAMURA discloses that the first-stage device A and the second-stage devices B and C are RO membrane devices (¶[0011]–¶[0014]).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over NAKAMURA as applied to Claim 1 above, and further in view of ITO et al. (US20180104652A1, hereinafter, ITO).
Regarding Claim 8, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. However, NAKAMURA does not explicitly disclose that “a dilute water has a water temperature of 25° C. or higher.”
ITO discloses a reverse osmosis membrane cleaning method and apparatus (¶[0001]). The RO membrane 2 is cleaned using water at a temperature above 45°C and up to 60°C (¶[0058]), which falls within the claimed range of “a water temperature of 25° C. or higher.”
The higher cleaning water temperature disclosed by ITO improves stripping and elution of scale from the RO membrane and provides a better cleaning effect than conventional cleaning water (¶[0059]). In view of NAKAMURA using the permeate from the first-stage RO membrane device A to clean the second-stage devices B and C, a person skilled in the art would heat that permeate to above 25°C to predictably improve scale removal during cleaning.
Therefore, it would have been obvious to a person having ordinary skill in the art, prior to the effective filing date of the claimed invention, to apply the higher cleaning water temperature, as disclosed by ITO, to the permeate used for cleaning the second-stage devices in the water treatment methods by NAKAMURA.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over NAKAMURA as applied to Claim 1 above, and further in view of COSTA et al. (US20070034571A1, hereinafter, COSTA).
Regarding Claim 9, NAKAMURA makes obvious the method for operating the desalting device of Claim 1. NAKAMURA discloses scale formation from raw-water constituents, including calcium salts, aluminum salts, and silica (¶[0064]). In Example 1, raw water having a calcium concentration of 20 ppm, a silica concentration of 15 ppm, and a pH of 8.5 undergoes RO treatment. The recovery rate of the first-stage RO membrane device A is set at 50% (¶[0065]). However, NAKAMURA does not explicitly disclose a water temperature of 20°C or higher, a pH of <6.0, presence of iron ions, or respective calcium ion, aluminum ion, iron ion, and silica concentrations in the first concentrated water.
COSTA discloses a method and related apparatus for desalinating water using high recovery reverse osmosis. The process permits recovery of 90% or more of the feedwater as purified product even when the feedwater contains a substantial amount of silica (¶[0001]). Selecting the RO system size and number of stages relative to the volume of acidic pH-adjusted feedwater being processed controls the retentate concentration and the content and recovery of retentate and permeate (¶[0017]).
Type 2 pretreatment alters the nature or amount of dissolved feedwater components without substantially changing the dissolved silica content, using processes such as softening and partial ion exchange. Pretreatment adjusts concentrations of components that can adversely affect RO performance, including calcium sulfate that forms scale and calcium, aluminum, and iron that promote or catalyze silica precipitation (¶[0019]–¶[0020]).
In Example 2, feedwater is treated with a weak acid cation exchange resin and sparged with nitrogen to remove carbon dioxide. The treated feedwater, at pH 2.7, undergoes RO treatment at 94% recovery, producing clear retentate having a pH of 3.4 and a silica concentration of 1084 ppm. Further tests vary feed silica concentration, recovery, and feed pH, producing retentates having pH 3.3 with silica at 1122 ppm and pH 5.0 with silica at 845 ppm (¶[0026]–¶[0027], Table 2). The disclosed retentate pH ranges from 3.3 to 5.0, and silica concentrations range from 845 to 1122 ppm (mg/L), which fall within the claimed ranges of “pH of <6.0” and “a silica concentration of 500 to 1500 mg/L.”
The feedwater pretreatment disclosed by COSTA adjusts concentrations of calcium, aluminum, and iron that can promote silica precipitation, while acidic RO operation supports efficient and stable treatment of silica-containing water (¶[0019]–¶[0020], ¶[0023]). In view of NAKAMURA’s two-stage RO treatment of raw water containing scale-forming constituents, a person skilled in the art would apply such pretreatment and acidic pH adjustment to iron-containing feedwater before first-stage RO treatment to predictably control silica precipitation and maintain stable operation.
Regarding the recited limitation “a water temperature of 20°C or higher,” this range encompasses ordinary room-temperature operation without requiring a separate heating step. Operating the first-stage RO device under such ambient conditions represents a routine selection of operating conditions without producing an unexpected result.
Regarding the claimed calcium, aluminum, and iron ion concentrations, the first concentrated water is an intermediate stream produced by the first-stage RO membrane device. Its properties depend on result-effective variables including feed-water composition, temperature, recovery rate, and membrane rejection. COSTA recognizes that these metals promote or catalyze silica precipitation and provides feedwater pretreatment to adjust their concentrations and control scaling. A person skilled in the art would optimize feedwater pretreatment and first-stage recovery through routine experimentation to establish workable calcium, aluminum, and iron ion concentrations for controlling silica precipitation (In re Aller, 220 F.2d 454, 456–57; 1955).
Therefore, it would have been obvious to a person having ordinary skill in the art, prior to the effective filing date of the claimed invention, to incorporate acidic feedwater pH adjustment and RO recovery control for feedwater containing iron ions, as disclosed by COSTA, into the first-stage RO treatment in the water treatment methods by NAKAMURA.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TAK L. CHIU whose telephone number is (703)756-1059. The examiner can normally be reached M-F: 9:00am - 6:00pm (CST).
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/TAK L. CHIU/Examiner, Art Unit 1771
/KRISHNAN S MENON/Primary Examiner, Art Unit 1771
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