Detailed Office Action
The communication dated 11/12/2025 has been entered and fully considered.
Claim 30 is new. Claims 3,4, 6-8, 10-11, 14-15, and 21 have been canceled. Claims 1, 9, 14-15, 21, 23 have been amended. Claims 1, 2, 5, 9, 12, 13, 16-20, 22, and 24-30 are pending.
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 Arguments
In light of cancelation the rejection towards claim 14 has been withdrawn.
Applicant argues that DREHMER introduces magnesium into the oxygen bleaching stage while the instant claims introduce the magnesium into the weak black liquor.
In response the Examiner agrees that DREHMER introduces magnesium into the oxygen delignification stage. However, the magnesium in this stage is washed from the pulp into filtrate which becomes part of the weak black liquor. The claims do not limit how the magnesium is introduced into the weak black liquor.
Applicant argues that ‘oxygen bleaching’ is not part of pulping itself.
The Oxygen bleaching of DREHMER is an oxygen delignification stage. Oxygen bleaching is used to mean oxygen delignification. The Examiner refers the applicant to the dictionary definition in Handbook of Pulp & Paper Terminology by SMOOK.
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Further, it is clear from DREHMER that the magnesium added to the pulp goes into the weak black liquor from the loops of Figure 9.
Applicant argues that ‘oxygen bleaching is not part of the pulping process and that the filtrate of ‘oxygen bleaching’ would not be combined with the weak black liquor filtrate. The applicant argues that the person of ordinary skill in the art would not modify DREHMER in any way to add the filtrate from the bleaching stage to the weak black liquor filtrate.
In response the Examiner does not suggest modifying DREHMER as argued by the applicant. DREHMER explicitly shows in Figure 9 that the magnesium added to the pulp becomes part of the black liquor. It even says so:
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The applicant appears confused because of the term ‘oxygen bleaching’ which is understood to be ‘oxygen delignification’ which is a secondary stage after pulping. GULLICHSEN which is already cited by the Examiner shows this in Figure 128.
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Claim Interpretation
In claim 13 the applicant amended the claims to state the “magnesium addition unit is configured and arranged to introduce magnesium into a stream of a weak black liquor”. This claim is now interpreted under 112(f) as it meets the three-pronged test [MPEP 2181 (I)].
Prong one: Unit is a nonce word for means [MPEP 2181 (I)(A)].
Prong two: “magnesium addition unit” is modified by the functional language “configured and arranged to introduce magnesium into a stream of a weak liquor” [MPEP 2181 (I)(B)].
Prong three: “magnesium addition unit” is not modified by sufficient structure [MPEP 2181 (I)(C)].
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.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 13 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 limitation “magnesium addition unit is configured and arranged to” invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. However, the written description fails to disclose the corresponding structure, material, or acts for performing the entire claimed function and to clearly link the structure, material, or acts to the function. Therefore, the claim is indefinite and is rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.
Applicant may:
(a) Amend the claim so that the claim limitation will no longer be interpreted as a limitation under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph;
(b) Amend the written description of the specification such that it expressly recites what structure, material, or acts perform the entire claimed function, without introducing any new matter (35 U.S.C. 132(a)); or
(c) Amend the written description of the specification such that it clearly links the structure, material, or acts disclosed therein to the function recited in the claim, without introducing any new matter (35 U.S.C. 132(a)).
If applicant is of the opinion that the written description of the specification already implicitly or inherently discloses the corresponding structure, material, or acts and clearly links them to the function so that one of ordinary skill in the art would recognize what structure, material, or acts perform the claimed function, applicant should clarify the record by either:
(a) Amending the written description of the specification such that it expressly recites the corresponding structure, material, or acts for performing the claimed function and clearly links or associates the structure, material, or acts to the claimed function, without introducing any new matter (35 U.S.C. 132(a)); or
(b) Stating on the record what the corresponding structure, material, or acts, which are implicitly or inherently set forth in the written description of the specification, perform the claimed function. For more information, see 37 CFR 1.75(d) and MPEP §§ 608.01(o) and 2181.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim 13 is rejected under 35 U.S.C. 102 (a)(1) as being clearly anticipated by The removal of aluminum from the recovery system of a closed kraft pulp mill by ULMGREN, hereinafter ULMGREN.
As for claim 13, ULMGREN discloses a kraft pulp mill [summary]. ULMGREN has a digester (hence kraft pulp). ULMGREN further discloses washing and the option oxygen pre-bleaching [pg. 4 col. 2 “oxygen bleaching”]. ULMGREN further discloses evaporators which are concentrator plant and recovery boiler which is a recovery plant [summary, pg. 1 col. 1 par. 6, pg. 5 col. 1 “process alternatives: 1]. ULMGREN discloses a causticizing unit [pg. 5 Figure 7]. Finally, ULMGREN discloses adding the magnesium sulfate at oxygen delignification which travels to the weak black liquor via the washers [pg. 7 col. 2 ‘oxygen bleaching’]. It is the Examiners position that this addition reads o “magnesium addition unit”.
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.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-2, 5, 9, 12-13, 16-17, 19-20, 22, and 24-30 are rejected under 35 U.S.C. 102(a)(1) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Impact of the Mg-Salt from the Oxygen Stage Washing Liquor on the Aluminum Build-up in the Alkali Loop by DREHMER, hereinafter DREHMER.
As for claims 1, 2, 9, 19, 20,and 30 DREHMER discloses introducing magnesium into the oxygen bleaching stage. This magnesium is then introduced from the pulp at the oxygen bleaching stage by washing [pg. 618 Conclusion par. 1 and Figure 9] to weak black liquor prior to evaporation.
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The concentrated black liquor is burned in the recovery boiler forming a magnesium containing smelt which becomes green liquor; hydrotalcite is formed from aluminum and magnesium in both the smelt and green liquor [pg. 617 col. 1 par. 1-2].
There is 325 mg magnesium in the black liquor per kilogram dissolved solids after the start of addition of magnesium to the oxygen delignification which is 13.4 moles Mg / kg DS [pg. 617 col. 1 Figure 4; 325 g Mg/kg DS * mol Mg / 24.3 g Mg]. The process of evaporation removes liquid not solids. Therefore the aluminum or magnesium per kg dissolved solids is substantially the same for weak black liquor or concentrated black liquor.
DREHMER also teaches 70 mg magnesium in the black liquor per kilogram dissolved solids prior to the addition of magnesium in the black liquor. This means that the total magnesium added into the weak black liquor is 255 g Mg/kg DS (325-70) which is 10.5 moles Mg / kg DS [pg. 617 col. 1 Figure 4; 255 g Mg/kg DS * mol Mg / 24.3 g Mg].
There is 50 mg aluminum in the black liquor per kilogram dissolved solids which is 1.9 moles Al / kg DS [pg. 617 col. 1 Figure 4; 50 g Al/kg DS * mol Al / 27 g Al].
This gives a molar ratio of Mg/Al in the weak black liquor of 5.5 Mg:Al (10.5/1.9 = 5.5) which is greater than the claimed range. However, this is at a steady state after the accumulated aluminum has been removed from the liquor cycle via separated green liquor dregs. The pulp mill recovery cycles are a dynamic system and before the aluminum is removed it starts out high in the black liquor.
Prior to treatment the black liquor has 160 mg aluminum in the black liquor per kilogram dissolved solids which is 5.9 moles Al / kg DS [pg. 617 col. 1 Figure 4; 160 g Al/kg DS * mol Al / 27 g Al].
Therefore at the beginning of treatment the molar ratio is 1.8 Mg:Al (10.5/5.9 = 1.8) which falls within the claimed range. As time goes on the ratio increases as the accumulated aluminum is removed via the green liquor dregs.
In the alternative the concentration of magnesium supplied is a clear-result effective variable that is directly related to the amount of aluminum retained in the liquor circulations [pg. 617 Figure 6 and pg. 616 col. 2 which shows magnesium forms a double salt with aluminum]. At the time of the invention it would be obvious to the person of ordinary skill in the art to optimize the amount of magnesium salt added to the weak black liquor through routine experimentation. The examiner notes differences in concentration will not typically support non-obviousness [MPEP 2144.05].
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955)
As for claims 5, 24, and 25, the treated white liquor has 8 mg/L of aluminum [pg. 617 col. 1 Figure 4]. A value of 8 mg/L is 8 ppm which falls within the claimed range.
As for claim 12, 22, and 26-29, the magnesium and aluminum all travel together from the boiler to green liquor prior to dreg removal [pg. 617 col. 1 par. 2]. Therefore, the molar ratio of magnesium to aluminum in the black liquor is substantially the same as it is in the green liquor prior to clarification.
There is 325 mg magnesium in the black liquor per kilogram dissolved solids after the start of addition of magnesium to the oxygen delignification which is 13.4 moles Mg / kg DS [pg. 617 col. 1 Figure 4; 325 g Mg/kg DS * mol Mg / 24.3 g Mg].
There is 50 mg aluminum in the black liquor per kilogram dissolved solids which is 1.9 moles Al / kg DS [pg. 617 col. 1 Figure 4; 50 g Al/kg DS * mol Al / 27 g Al].
This gives a ratio of 13.4/1.9 or 7.1 moles Mg:Al which falls within the claimed range. At the start of treatment when the aluminum accumulation has not been substantially removed the black liquor has 160 mg aluminum in the black liquor per kilogram dissolved solids which is 5.9 moles Al / kg DS [pg. 617 col. 1 Figure 4; 160 g Al/kg DS * mol Al / 27 g Al].
This gives a ratio of 13.4/5.9 of 2.3 moles Mg/Al. This ratio increases as the Aluminum is removed over time.
As per above it would be obvious to the person of ordinary skill in the art to optimize the amount of magnesium added to the WBL through routine optimization.
As for claims 13, DREHMER discloses a kraft pulp mill [abstract ‘sulphate’ means kraft cooking] which has a digesting unit which turns wood chips into pulp using white liquor [Figure 9]. DREHMER discloses evaporators [abstract, pg. 616 col. 2 par. 1, pg. 617 col. 1 par. 3]. DREHMER discloses an oxygen bleaching stage in which magnesium salt is added and washer which introduces the washing filtrate (which now comprises magnesium) into the weak black liquor prior to the recovery boiler [pg. 616 col. 2 last par – pg. 617 col. 1 par. 1 and 2]
As for claims 16-17, the magnesium is supplied as a magnesium salt [title, pg. 617 col. 1 par. 1].
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over DREHMER in view of Chemical Pulping by GULLICHSEN, hereinafter GULLICHSEN
As for claim 18, DREHMER discloses using a magnesium salt in the oxygen delignification stage but does not specify the salt used. GULLICHSEN discloses adding Magnesium sulfate to oxygen delignification [pg. A140 Figure 130]. At the time of the invention it would be obvious to the person of ordinary skill in the art to add magnesium sulfate to the pulp prior to oxygen delignification. The person of ordinary skill in the art would be motivated to do so to increase selectivity and intrinsic viscosity of the pulp [GULLICHSEN pg. A140 section 4.3.1]. The person of ordinary skill in the art would expect success as DREHMER already suggests adding magnesium salts to oxygen delignification.
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 ANTHONY J CALANDRA whose telephone number is (571)270-5124. The examiner can normally be reached Monday-Friday 7:45 AM -4:15 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, Abbas Rashid can be reached at (571)270-7457. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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ANTHONY J. CALANDRA
Primary Examiner
Art Unit 1748
/Anthony Calandra/Primary Examiner, Art Unit 1748