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 Amendment
The Amendment filed August 26th, 2025 has been entered. Examiner acknowledges cancellation of Claim 11. Claims 1-10 and 12-24 remain pending in the application. Applicant’s amendments to the Claims have overcome the 112(b) and 102(a)(1) rejections previously set forth in the Non-Final Office Action mailed May 27th, 2025. Therefore, these rejections have been withdrawn. However, upon further consideration in light of these amendments, a new grounds of rejection is made in view of 35 USC § 103.
Response to Arguments
Applicant’s arguments regarding rejections under 35 U.S.C. § 112(b), see page, filed August 26th, 2025, with respect to claims 10 and 20 have been fully considered and are persuasive. The 112(b) rejection of claims 10 and 20 has been withdrawn.
Applicant's arguments regarding rejections under 35 U.S.C. § 103 on pages 9-11 filed August 26th, 2025 have been fully considered but they are not persuasive.
Applicant argues that Hong (EP3848331A1) fails to disclose or suggest that the electrolysis cell is powered by electricity generated by hydrocarbon combustion, and therefore cannot anticipate or render obvious the amended claims. Examiner agrees that Hong expressly discloses its electrolysis cell using solar electrical energy and therefore no longer anticipates amended claim 1. However, the Examiner maintains that it would have been obvious to a person of ordinary skill in the art to substitute Hong’s solar electrical source with electricity generated by hydrocarbon combustion, as taught or suggested by Savage (US20140151300A1). Please see new 103 rejection below for further explanation.
Applicant further argues that Savage is directed to treating produced water and does not disclose or suggest an electrolysis cell, and therefore cannot be properly combined with Hong. This argument is not persuasive. It is well established that references need not be combined for the same purpose as the applicant’s invention (In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981)). Savage is cited not for disclosing an electrolysis cell, but for teaching a hydrocarbon-producing and water treatment environment where electric power and CO2 are generated from on-site hydrocarbon combustion. Hong’s electrolysis system requires electrical power and benefits from CO2 for its carbonate precipitation reactions (Hong par. [0121—126]). Savage teaches that such resources (hydrocarbon combustion products and CO2 emissions) are readily available in the same type of industrial setting. A person of ordinary skill in the art would have recognized that Hong’s electrolysis process could be powered by on-site hydrocarbon generators described in Savage to achieve an integrated system using available fuel and by-products, resulting in predictable improvements in energy efficiency and carbon utilization. Therefore, the combination is properly based on complementary teachings addressing a known engineering need.
Applicant further argues that the combination of Hong and Savage represents hindsight reconstruction, since Hong’s system is solar-based while Savage’s is unrelated to electrolysis. This argument is unpersuasive. The Examiner’s combination is based on explicit teachings in the prior art and ordinary engineering knowledge, not on applicant’s disclosure. Hong emphasizes sustainable, integrated systems for desalination and chemical production using electrical energy (Hong par. [0018-0022] and teaches using CO2 to react with calcium ions for carbon sequestration (Hong par. [0121—126]). Savage teaches treatment of produced water from oil and gas wells using electrically driven and thermally driven processes such as electrocoagulation, ultrafiltration, and crystallization (Savage par. [0001-0011] and examples I and II). Savage’s disclosure places these treatment systems at hydrocarbon-production facilities, where on-site combustion of available hydrocarbons is an ordinary and well-known means for providing both heat and electrical power for field equipment. A person of ordinary skill in the art reading Hong and Savage together would have recognized that Hong’s electrolysis system requires a source of electrical energy, and that in the produced water environment described by Savage, such electricity would conventionally be provided by on-site hydrocarbon-fueled generators rather than by solar panels, particularly when solar energy is unavailable. Substituting one well-known energy source for another to achieve the same electrical function constitutes a predictable design choice, not an inventive act (see MPEP 2144.06 II). Therefore, the proposed modification results from the ordinary skill and common sense of an engineer seeking to implement Hong’s electrolysis process in the produced-water setting of Savage, rather than from knowledge of applicant’s disclosure. The combination follows a known problem with a known solution-providing a reliable on-site power source for electrically driven treatment systems-and yields predictable results consistent with both references. Accordingly, the Examiner’s rationale does not rely on hindsight reconstruction but on explicit teachings and well-established design principles within the field.
Applicant further argues that Savage’s hydrocarbons are intended for sale or recovery, not for combustion to generate power; therefore, there would be no motivation to combust hydrocarbons on site. This argument is not persuasive. Savage identifies that oil and gas production sites routinely employ combustion systems and thermal units in remote locations (Savage par. [0001-0007]) and that these processes may be used for zero-liquid discharge treatment (Savage par. [0009]), all of which inherently rely on fuel combustion. Furthermore, Savage acknowledges the presence of electrocoagulation systems that require electrical energy input (Savage par. [0011] and [0042]), evidencing that such facilities are already equipped for on-site power generation. Therefore, using a portion of available hydrocarbons as fuel for electricity generation is consistent with Savage’s operating environment and would have been a routine design choice to meet energy demands for Hong’s electrolysis process.
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 factual inquiries 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.
Claims 1-4, 9-10, 12-14 and 19-24 are rejected under 35 U.S.C. 103 as being unpatentable over Hong (EP-3848331-A1) in view of Savage (US-20140151300-A1).
Regarding claim 1, Hong discloses a method comprising: obtaining produced water containing Ca2+ ions (Hong abstract and par. [0123]); combining the produced water with NaOH (Hong par. [0029]) to increase a pH (Hong par. [0011]) of the produced water; combining the produced water with byproducts of hydrocarbon combustion containing CO2 (Hong par. [0122] first concentrated water and carbon dioxide are supplied to the discharging unit and water and carbon dioxide are both byproducts of combustion containing CO2), thereby dissolving the CO2 in the produced water and increasing a concentration of CO32- that combines with the Ca2+ (Hong par. [0123]) to produce CaCO3 (Hong par. [0124]); precipitating the CaCO3 (Hong par. [0123]) to produce a CaCO3 product stream and an aqueous product stream; and providing at least a portion of the aqueous product stream to an electrolysis cell (Hong par. [129] "chlor-alkali process unit"), wherein the electrolysis cell produces the NaOH (Hong par. [0099]) that is combined with the produced water.
Hong expressly teaches powering the electrolysis cell using solar electrical energy rather than electricity generated by hydrocarbon combustion, therefore Hong does not disclose wherein the electrolysis cell is powered by electricity generated by the hydrocarbon combustion.
Savage is directed to treating produced water from oil and gas operations (Savage par. [0001]). Savage teaches that such treatment systems are co-located with hydrocarbon production sites and employ electrochemical and thermal unit operations such as electrocoagulation, ultrafiltration and crystallization (Savage par. [0011], [0027]). While Savage does not expressly state that electricity is generated on-site, the reference evidences that electrical energy is required (Savage par. [0011] and [0042]) and that the facilities operate in an environment where hydrocarbons are readily available as fuel for heating or power generation, in remote locations where solar energy sources may, at times, not be available. Thus Savage provides contextual support that produced water treatment facilities at oil and gas fields inherently have access to hydrocarbon fuel (Savage par. [0028]) and require substantial electrical energy to run their systems.
It would have been obvious to one of ordinary skill in the art at the time of filing to substitute Hong’s solar powered energy source with electricity generated by hydrocarbon combustion as would have been available at a hydrocarbon-production site such as described by Savage. Both energy sources serve the same purpose or supplying electrical power to an electrolysis system and their substitution represents a predictable use of known alternatives according to their established functions (see MPEP 2144.06 II). A person of ordinary skill in the art would have recognized that operating Hong’s electrolysis process within the produced water environment of Savage would require a reliable on-site energy supply and that combusting a portion of the available hydrocarbons to generate the necessary electricity would be an obvious engineering adaptation yielding expected results, namely, self-sufficient operation and utilization of existing fuel resources.
Regarding claim 2, Hong in view of Savage discloses the method of claim 1, wherein the produced water further contains Mg2+ ions that combine with the NaOH to produce Mg(OH)2 (Hong par. [0075] describes the precipitation reaction of Mg2+ with sodium hydroxide which forms Mg(OH)2).
Regarding claim 3, Hong in view of Savage discloses the method of claim 2 further comprising controlling the pH of the produced water (Hong discloses this repeatedly including in par. [0105] using hydrochloric acid and par. [0101] using sodium hydroxide).
Hong in view of Savage does not disclose that this control is to selectively precipitate the Ca2+ ions while precipitating relatively few Mg2+ ions, however It would have been obvious to one of ordinary skill in the art that calcium carbonate begins to precipitate at a pH around 8.3-8.5 while magnesium carbonate requires higher pH, typically around 9.0 to 10.0 to overcome the higher solubility of magnesium. Hong does disclose in par. [0012] that when the pH is “adjusted to approximately 8.2 by use of sodium hydroxide, carbon dioxide is converted into bicarbonate ions that are removable through the reverse osmosis membrane” it is preferentially the Ca2+ ions that are being targeted by this pH control to precipitate and remove carbonate ions and bicarbonate ions (Hong par. [0013]).
Regarding claim 4, Hong in view of Savage discloses the method of claim 1, further comprising using at least a portion of the aqueous product stream for hydraulic fracturing of a hydrocarbon bearing formation (Savage par. [0007] suggests this as a beneficial use).
Regarding claim 9, Hong in view of Savage discloses the method of claim 1 further comprising combining NaOH produced by the electrolysis cell with a portion of the CO2 from the byproducts of hydrocarbon combustion (Hong par. [0122] first concentrated water and carbon dioxide are supplied to the discharging unit and water and carbon dioxide are both byproducts of combustion containing CO2) to produce Na2CO3. Hong does not disclose the production of Na2CO3; however it would be obvious to a person of ordinary skill in the art that after the addition of NaOH to achieve 8.2 pH bicarbonate would begin to form. As the NaOH is continually added carbonate ions would also form as the pH increases. Hong discloses this in par. [0012] and goes on to disclose in par. [0013] that the precipitation and removal of carbonate would reduce the pH and thus the pH is raised by increasing the concentration of NaOH to recover alkalinity. It would be obvious to a person of ordinary skill in the art that the more NaOH is added the pH will increase to a point at which Na2CO3 is also formed.
Regarding claim 10, Hong in view of Savage discloses the method of claim 9 further comprising combining the Na2CO3 with the produced water (See rationale presented above regarding claim 9), thereby enhancing production of CaCO3. It would have been obvious to a person of ordinary skill in the art that addition of NaOH (Hong par. [0012]) would lead to formation of Na2CO3 which further raises the pH which favors carbonate ion stability over bicarbonate in the water, reducing the formation of calcium bicarbonate in favor of CaCO3.
Regarding claim 12, Hong in view of Savage discloses the method of claim 1, wherein H2 gas and Cl2 gas produced by the electrolysis cell (Hong Fig. 12 shows Cl2 produced in cell #233 and going to chlorine tank #273 and H2 produced at the other electrode and stored in a hydrogen tank #275) are combined to produce HCI (Hong par. [0030]).
Regarding claim 13, Hong in view of Savage discloses the method of claim 1. Hong in view of Savage does not disclose that the NaOH and Cl2 produced by the electrolysis cell are provided as inputs to a NaClO reactor to produce NaClO. However, Hong discloses in par. [0133] that “by lowering the pH of the second concentrated water before introduction into the chlor-alkali process unit, it is possible to prevent the second concentrated water from reacting with chlorine gas in the chlor-alkali process unit to produce hypochlorous acid (HCIO) and other compounds.” It would have been obvious to one of ordinary skill in the art that if the formation of NaClO were preferred for sanitation in lieu of the hydrochloric acid, then the omission of the acid would provide inputs to a NaClO reactor to produce NaClO.
Regarding claim 14, Hong in view of Savage discloses the method of claim 3 further comprising: providing at least a portion of the aqueous product stream as an input into a Mg2+ precipitation process that further comprises adding NaOH to precipitate Mg(OH)2 to produce a further aqueous product stream (Hong par. [0075] describes the precipitation reaction of Mg2+ with sodium hydroxide which forms Mg(OH)2); and providing at least a portion of the further aqueous product stream to the electrolysis cell (Hong par. [129] “chlor-alkali process unit”).
Regarding claim 19, Hong in view of Savage discloses the method of claim 14 further comprising combining NaOH produced by the electrolysis cell with a portion of the CO2 from the byproducts of hydrocarbon combustion (Hong par. [0122] first concentrated water and carbon dioxide are supplied to the discharging unit and water and carbon dioxide are both byproducts of combustion containing CO2) to produce Na2CO3. Hong in view of Savage does not disclose the production of Na2CO3; however it would be obvious to a person of ordinary skill in the art that after the addition of NaOH to achieve 8.2 pH, bicarbonate would begin to form. As the NaOH is continually added carbonate ions would also form as the pH increases. Hong discloses this in par. [0012] and goes on to disclose in par. [0013] that the precipitation and removal of carbonate would reduce the pH and thus the pH is raised by increasing the concentration of NaOH to recover alkalinity. It would be obvious to a person of ordinary skill in the art that the more NaOH is added the pH will increase to a point at which Na2CO3 is also formed.
Regarding claim 20, Hong in view of Savage discloses the method of claim 19 further comprising combining the Na2CO3 with the produced water (See rationale presented above regarding claim 19), thereby enhancing production of CaCO3. It would have been obvious to a person of ordinary skill in the art that addition of NaOH (Hong par. [0012]) would lead to formation of Na2CO3 which further raises the pH which favors carbonate ion stability over bicarbonate in the water, reducing the formation of calcium bicarbonate in favor of CaCO3 thereby enhancing production of CaCO3.
Regarding claim 21, Hong in view of Savage discloses the method of claim 14, wherein the electrolysis cell is powered by electricity produced by the energy from the hydrocarbon combustion (by suggestion of Savage, it would have been obvious to a person of ordinary skill to utilize a portion of the fuel provided from the process of the system to power the system).
Regarding claim 22, Hong in view of Savage discloses the method of claim 14 wherein H2 gas and Cl2 gas produced by the electrolysis cell (Hong Fig. 12 shows Cl2 produced in cell #233 and going to chlorine tank #273 and H2 produced at the other electrode and stored in a hydrogen tank #275) are combined to produce HCI (Hong par. [0030]).
Regarding claim 23, Hong in view of Savage discloses the method of claim 14. Hong does not disclose that the NaOH and Cl2 produced by the electrolysis cell are provided as inputs to a NaClO reactor to produce NaClO. However, Hong discloses in par. [0133] that “by lowering the pH of the second concentrated water before introduction into the chlor-alkali process unit, it is possible to prevent the second concentrated water from reacting with chlorine gas in the chlor-alkali process unit to produce hypochlorous acid (HCIO) and other compounds.” It would have been obvious to one of ordinary skill in the art that if the formation of NaClO were preferred for sanitation in lieu of the hydrochloric acid, then the omission of the acid would provide inputs to a NaClO reactor to produce NaClO.
Regarding claim 24, Hong discloses the method of claim 1, wherein the produced water is selected from the group consisting of water produced from a hydrocarbon well and seawater (Hong par. [0001]).
Claims 5-8 and 15-18 are rejected under 35 U.S.C. 103 as being unpatentable over Hong (EP-3848331-A1) in view of Savage (US-20140151300-A1) as applied to claim 1 and 14 above, and further in view of Saha (EP-0243557-A1).
Regarding claim 5, Hong in view of Savage disclose the method of claim 1.
Hong in view of Savage does not disclose pretreating the portion of the aqueous product stream provided to the electrolysis cell using an ion exchange process that reduces trace ions other than Na+ and Cl- in the aqueous product stream to produce an output stream having acceptable ion concentrations for operation of the electrolysis cell.
Saha discloses a method for water treatment (Saha title “method for removing strontium and/or cesium ions from an aqueous solution”) comprising pretreating the portion of the aqueous product stream (Saha p. 3 line 54 and table on page 5) using an ion exchange process that reduces trace ions other than Na+ and Cl- in the aqueous product stream to produce an output stream having acceptable ion concentrations for operation of the electrolysis cell (Saha table on page 5 shows the removal of the elements Ca, Mg and Fe with numbers indicating they are below the required concentrations in samples 1-48).
It would have been obvious to one of ordinary skill in the art at the time of filing to combine the teaching of Saha with the method of Hong in view of Savage. Ion exchange units are commonly known in the art and there would have been motivation to do so as well. Hong discloses in par. [0051] that “by preventing the scaling occurring in the distillation membrane or a membrane during the distillation process, it is possible to extend service life of the concentrated water treatment unit.” The addition of the ion exchange process could eliminate the need for the antiscalant used in the method completely and reduce costs in its use.
Regarding claim 6, the combination of Hong, Savage and Saha discloses the method of claim 5 wherein pretreating the portion of the aqueous product stream provided to the electrolysis cell further comprises increasing a NaCl concentration (Hong par. [0130]) of the output stream prior to providing it as an input stream to the electrolysis cell (Hong “chlor-alkali process unit” 233), thereby improving electrolysis cell efficiency.
Regarding claim 7, the combination of Hong, Savage and Saha discloses the method of claim 5 further comprising providing a portion of the output stream to the electrolysis cell to a de-salinification process that produces NaCl (Hong par. [0152]) and a reduced salinity water product.
Hong in view of Savage and further in view of Saha does not disclose that the portion of the output stream is not provided as an input stream, however this would this would have been within the ability of one of ordinary skill in the art at the time of filing to provide another line such that at least a portion of which is not part of the input stream.
Regarding claim 8, the combination of Hong, Savage and Saha discloses the method of claim 7 further comprising adding NaCl produced by the de-salinification process to the output stream prior to providing it as an input stream to the electrolysis cell (Hong par. [0107] discloses that it is possible to recycle crystalized salt), thereby improving electrolysis cell efficiency.
Regarding claim 15, the combination of Hong, Savage and Saha discloses the method of claim 14 further comprising: pretreating the portion of the further aqueous product stream provided to the electrolysis cell using an ion exchange process (Saha p. 3 line 54 and table on page 5) that reduces trace ions other than Na+ and Cl- in the aqueous product stream to produce an output stream having acceptable ion concentrations for operation of the electrolysis cell (Saha table on page 5 shows the removal of the elements Ca, Mg and Fe with numbers indicating they are below the required concentrations in samples 1-48).
Regarding claim 16, the combination of Hong, Savage and Saha discloses the method of claim 15 wherein pretreating the portion of the aqueous product stream provided to the electrolysis cell further comprises increasing a NaCl concentration of the output stream (Hong discloses in one embodiment in par. [0130]) prior to providing it as an input stream to the electrolysis cell (Hong par. [0130] “chlor-alkali process unit” #233 Fig. 8 in this embodiment), thereby improving electrolysis cell efficiency.
Regarding claim 17, the combination of Hong, Savage and Saha discloses the method of claim 15 further comprising providing a portion of the output stream not provided as an input stream to the electrolysis cell to a de-salinification process that produces NaCl (Hong par. [0152]) and a reduced salinity water product.
Hong in view of Savage and further in view of Saha does not disclose that the portion of the output stream is not provided as an input stream, however this would this would have been within the ability of one of ordinary skill in the art at the time of filing to provide another line such that at least a portion of which is not part of the input stream.
Regarding claim 18, the combination of Hong, Savage and Saha discloses the method of claim 17 further comprising adding NaCl produced by the de-salinification process to the output stream prior to providing it as an input stream to the electrolysis cell (Hong par. [0107] discloses that it is possible to recycle the crystalized salt), thereby improving electrolysis cell efficiency.
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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/W.A.G./Examiner, Art Unit 1779
/Bobby Ramdhanie/Supervisory Patent Examiner, Art Unit 1779