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
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 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 1-3 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Lindahl (US4599138A) in view of Averheim (EP3399095A1).
In regards to claim 1, Lindahl teaches a method of treating biomass which compresses and dewaters a biomass (Col. 3 Lines 15-21, “In accordance with the process of this invention, particulate lignocellulosic material is pretreated to re move heavy metals and resins without any delignification and/or defibration, which comprises washing particulate lignocellulosic material; compressing the washed material to a solids content of at least 40% to remove undiluted, absorbed liquid”)
that feeds the biomass along with a treatment liquid (Col. 3 Lines 21-25, “…impregnating the compressed material with an alkaline aqueous solution…”; Fig 1)
which is discharged, compressed and dewatered (Col. 7 Lines 47-49, “The feeder 9 is also equipped with a conically shaped ram 9a for compressing the chips to increase the density of the material”; Fig. 1, 9a)
in an impregnator treatment vessel (Col. 8 Lines 29-32, “The pretreating solution charged through the duct 7 into the impregnating vessel 5 was an aqueous solution of diethylenetriamine pentaacetic acid, sodium bisulfite and sodium hydroxide”)
where there is two plug screw devices used in the process (Fig. 1).
Lindahl does not teach the hydrolysis of a compressed and dewatered biomass.
Averheim teaches a method of treating biomass involving hydrolysis of a compressed and dewatered biomass (Col. 1 Lines 5-9, “The invention generally relates to a treatment of biomass. In particular, the invention relates to a method and a device for treating biomass, wherein the biomass is exposed to a prehydrolysis step first and to a hydrolysis step subsequently”; Col. 1 Lines 41-49, “In one step of the method biomass is fed to a pressurized prehydrolysis reactor unit by means of a feeding system, wherein by means of the feeding system the biomass is compressed, and – in parallel – a filtrate is squeezed out of the biomass by means of the feeding system. For example, biomass that has been moisturized by e.g. being soaked in water before, can be dewatered by the compression of the feeding system”). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to treat the biomass produced after the second plug screw device of Lindahl in the hydrolysis as taught by Averheim in order to produce monomeric sugars as a final product of the biomass (Col. 12 Lines 6-9, In the hydrolysis reactor unit 10 an enzymatic hydrolysis process is applied to the biomass 2, wherein cellulose and yet unreacted hemicellulose is converted into monomeric sugars”).
In regards to the difference of solids content being between 1% and 6%, example 1 has a DS1 of 42% and DS2 of 41% (Col. 8 Lines 24-28, “lower end of which was connected to the screw feeder 3. During the passage of the chips through the screw feeder 3, they were compressed to a solids content of 42%...”; Col. 8 Lines 43-48, “After a 10 minutes transit time the treated chips reached the second screw conveyor 9, and were compressed to a solids content of 41%...”). This would have a difference of solids content (DS1-DS2) of 1%, which is infinitesimally different from the range of the instant claim and where one skilled in the art would not expect a difference in properties due to the extremely small difference. Thus, a prima facie case of obviousness exists. See MPEP 2144.05 I.
Lindahl and Averheim do not explicitly teach that the first plug screw device is configured or controlled to provide higher compression or dewatering than the second plug screw device. However, as discussed above, the solid content difference of 1% shows that the dewatering devices are configured as claimed where the first plug screw device has a higher compression or dewatering than the second plug screw device. Further, the determination of the proper amount of compression in each step would have been obvious to one of ordinary skill in the art with the motivation of providing a product with the desired solids content.
In regards to claim 2, Lindahl does not explicitly teach that the difference in solids content is between 2% and 5%. However, Lindahl teaches that the solids content is at least 40%. If the solids content for DS1 was 42%, as taught in example 1, and DS2 was 40% as needed (Abstract, “…compressing the washed material to a solids content of at least 40% to remove absorbed and excess liquid…”), the difference of solids content would be 2%, which is infinitesimally different from the range of the instant claim and where one skilled in the art would not expect a difference in properties due to the extremely small difference. Thus, a prima facie case of obviousness exists. See MPEP 2144.05 I.
In regards to claim 3, Lindahl teaches that the solids content of the washed material is between 35% and 60% (Abstract, “…compressing the washed material to a solids content of at least 40% to remove absorbed and excess liquid…”).
Claims 4, 5, and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Lindahl (US4599138A) in view of Averheim (EP3399095A1) and further in view of Lambert (US20190271113A1),
In regards to claim 4, Lindahl does not teach or suggest impregnation where the treatment liquid is an acid or catalyst.
Lambert teaches that impregnation liquid can consist of an acid or catalyst (Para. 0044, “According to an embodiment of the invention, the impregnation liquid comprises chemicals selected from the group consisting of an acid, a catalyst or mixtures thereof”). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to use the impregnation liquid taught by Lambert in the embodiment taught by Lindahl for a more rapid and/or selective hydrolysis for the biomass (Para. 0067, “The impregnation liquid may for instance be an acidic liquid. Residual acidic liquid can be recovered in the process and at the same time a more rapid and/or a more selective hydrolysis can be achieved since the acidic liquid functions as a catalyst in the hydrolysis process”).
In regards to claim 5, Lindahl teaches an impregnator that is vertical where biomass is fed to the impregnating vessel from below and is discharged in the upper part (Fig. 1). Lindahl does not teach or suggest having a predetermined fill level in the impregnator.
Lambert teaches a predetermined fill level of the impregnation liquid in a vertical impregnating vessel (Para. 0007, “For example, the first reactor unit is a longitudinal vessel arranged vertically with respect to an earth's surface. In this manner, it is possible to fill the first reactor unit with impregnation liquid up to a predetermined fill level such that the entire biomass is transferred through the impregnation liquid. This means that the biomass is transferred in an upward direction within the first reactor unit and through the impregnation liquid such that a homogeneous impregnation of the biomass with the impregnation liquid is achieved”). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to use the predetermined fill level of Lambert in the apparatus of Lindahl in order to achieve homogenous impregnation of the biomass with the treatment liquid.
In regards to claim 8, Lindahl does not teach or suggest a buffer bin being used in the apparatus prior to hydrolysis.
Lambert teaches that a buffer bin is placed between a first and second reactor unit where hydrolysis can take place (Para. 0076, “The impregnated biomass 2a is then fed into a buffer tank 15 which is arranged between the first reactor unit 10 and a second reactor unit 20 in which a hydrolysis of the impregnated biomass 2a takes place”). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to use the buffer bin taught by Lambert to control the flow of biomass into the hydrolysis tank.
Claims 15 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Lindahl (US4599138A) in view of Averheim (EP3399095A1), Lehoux (WO2015077885A1) and further in view of Reitter (US4427453A).
In regards to claims 15 and 16, Lindahl and Averheim do not explicitly teach that the plug screws comprise plug pipes and dewatering holes where the first plug screw has less dewatering holes than the second plug screw device.
Lehoux teaches a screw press device that has multiple perforations for the drainage of water (Page 3 Lines 8-10, “United States Patent US 7,357,074 is directed to a screw press with a conical dewatering housing with a plurality of perforations for the drainage of water from bulk solids compressed in the press”). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to determine the devices and number of dewatering holes in a plug screw given the solid/liquid to be separated as well as the desired solids content of the final product as more perforations decreases the pressure resistance (Page 3 Lines 11-12, “As will be readily understood, the higher the number of perforations in the housing, the lower the pressure resistance of the housing”). The pressure is important as evidenced by Reiter as it allows a pressure seal to be formed within a housing (Col. 2 Lines 52-61, “The material is injected into the charging opening and is moved by the worm under strong compression, and thus high pressure, to the smaller end where it is forced through the exit sleeve as a compressed plug. The plug tube or exit sleeve can be chosen in such a way that the plug forms a sufficient pressure seal under continuous feeding of the material into the pressure vessel. The conical housing is provided with perforations so liquid is squeezed out from the material during the compression”).
Response to Arguments
Applicant's arguments filed 10/06/2025 have been fully considered but they are not persuasive.
In regards to applicant’s remarks on pages 6-8, applicant states that Lindahl teaches away from hydrolysis.
It is first noted, that the hydrolysis discussed as being non-preferrable in column 5 of Lindahl would be before the dewatering/impregnation/dewatering steps (the delignification process). Lindahl discusses, “when the delignification process of the instant invention is applied to paper pulp, it is usually desirable to avoid hydrolysis of the cellulose”, i.e. hydrolysis is usually not desirable before the delignification steps. Lindahl does not discourage the use of hydrolysis after the delignification steps.
Lindahl teaches that hydrolysis can be performed on a biomass, such as raw lignocellulosic materials (Col. 5 Lines 61-64, “In the case of raw lignocellulosic materials, such as wood, such a treatment may be accompanied by hydrolysis of the cellulose, with the formation of additional acids”) and example I uses spruce wood chips (Col. 8 Lines 18-20, “Spruce logs were made into chips, the average length of which was about 25mm, average width about 20 mm, and average thickness of 3 mm”). Lindahl also teaches that it is usually desirable to avoid hydrolysis of cellulose, but not always (Col. 2 Lines 34-44, “U.S. Pat. No. 4,152,197 patented May 1, 1979 to Lindahl et al., provides process and apparatus for the preparation of improved high-yield cellulose pulps, such as semichemical, chemimechanical, thermomechanical, and mechanical pulps, which comprises mechanically defibrating a mixture of particulate lignocellulosic materials which have been partially pulped and softened to different extents. Part of the raw lignocellulosic material in particulate form is washed, moistened with steam, impregnated with pulping chemicals and pulped to a yield of from about 65 to about 92%”). Averheim also teaches that hydrolysis can be applied to a compressed and dewatered biomass produce monomeric sugars as a final product (Col. 12 Lines 6-9, “In the hydrolysis reactor unit 10 an enzymatic hydrolysis process is applied to the biomass 2, wherein cellulose and yet unreacted hemicellulose is converted into monomeric sugars”), where the cellulose fibers are dissolved from the hydrolysis (Col. 1 Lines 13-16, “Prehydrolyses with the purpose of dissolving hemicellulose sugars from a lignocellulosic biomass (often called pretreatment if preceding an enzymatic hydrolysis stage) are known”). In regards to Lindahl’s solid dry contents, Lindahl teaches that the material has a solid content of at least 40% (Col. 3 Lines 15-35, “In accordance with the process of this invention, particulate lignocellulosic material is pretreated to re move heavy metals and resins without any delignification and/or defibration, which comprises washing particulate lignocellulosic material; compressing the washed material to a solids content of at least 40% …”).
In regards to applicant’s remarks of the dry solids content if hydrolysis was performed on pages 7-8, Lindahl teaches that the solids content of the washed material is at least 40%. Even if the hydrolysis as taught by Averheim was performed, the process of biomass treatment as taught by Lindahl teaches a solids content of at least 40% to remove the absorbed and excess liquid from a washed impregnated material.
In regards to applicant’s remarks on Lindahl teaching higher dewatering in the second compression on page 8, Lindahl teaches that compression in the respective plug screw feeder can be lower as the biomass is transported (Col. 8 Lines 24-28, “lower end of which was connected to the screw feeder 3. During the passage of the chips through the screw feeder 3, they were compressed to a solids content of 42%...”; Col. 8 Lines 43-48, “After a 10 minutes transit time the treated chips reached the second screw conveyor 9, and were compressed to a solids content of 41%...”). This would have a difference of solids content (DS1-DS2) of 1%, which is infinitesimally different from the range of the instant claim and where one skilled in the art would not expect a difference in properties due to the extremely small difference. Even if hydrolysis was performed, the compression in the second plug screw feeder would be lower than the first plug screw feeder as the solid content of the second screw conveyer is lower than the first plug screw feeder.
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 JAANZEB RAJA whose telephone number is (703)756-4531. The examiner can normally be reached M - F 8:30-6.
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, Anthony Zimmer can be reached at 571-270-3591. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/JAANZEB C RAJA/Examiner, Art Unit 1736
/ANTHONY J ZIMMER/Supervisory Patent Examiner, Art Unit 1736