Prosecution Insights
Last updated: May 29, 2026
Application No. 18/139,447

Pyrolysis Plants and Methods for Thermal Mineralization of Biomass and Production of Combustible Gases, Liquids and Biochar

Non-Final OA §103§112
Filed
Apr 26, 2023
Priority
Nov 02, 2020 — DK PA 2020 01242 +1 more
Examiner
MERKLING, MATTHEW J
Art Unit
1725
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Frichs Holding 2 Aps
OA Round
1 (Non-Final)
68%
Grant Probability
Favorable
1-2
OA Rounds
0m
Est. Remaining
81%
With Interview

Examiner Intelligence

Grants 68% — above average
68%
Career Allowance Rate
857 granted / 1262 resolved
+2.9% vs TC avg
Moderate +13% lift
Without
With
+13.0%
Interview Lift
resolved cases with interview
Typical timeline
3y 1m
Avg Prosecution
43 currently pending
Career history
1312
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
78.7%
+38.7% vs TC avg
§102
13.9%
-26.1% vs TC avg
§112
5.7%
-34.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1262 resolved cases

Office Action

§103 §112
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 . 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. Specification The specification and drawings have been reviewed and no clear informalities or objections have been noted. Election/Restrictions Applicant’s election without traverse of Group I in the reply filed on 2/20/2026 is acknowledged. 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. Claims 1-7 are 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. In claim 1, line 8, Applicant claims “a gas accelerator configured for recirculating the pyrolysis gas” and then in line 11, Applicant claims “a carbon separator recirculating pyrolysis gas to a preheater…”. It is not clear if the “pyrolysis gas” in each of these limitations is the same pyrolysis gas or different pyrolysis gas. For purposes of this examination, it will be assumed that these two recitations are directed to the same pyrolysis gas. A correction for this clarity issue would be to amend line 11 such that it reads “a carbon separator recirculating the pyrolysis gas”. 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) 1-7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Piskorz (WO 97/44410) in view of Coates (US 2010/0294700). Regarding claim 1, Piskorz discloses a pyrolysis plant comprising: a reactor (205) for producing pyrolysis gas from biomass (this italicized portion does not further define the claimed apparatus but rather recites the intended purpose of the reactor), the reactor comprising: one or more reaction channels (inside reactor 205, there is formed a channel) linked thermally with at least one heating circuit configured to heat the one or more reaction channels to a temperature that gasifies the biomass (adjacent to reactor 205 is heating channel/circuit 204, see Fig. 1 which illustrates this); and a feed section configured for feeding the biomass into the one or more reaction channels (such as feed section which includes hopper 101 and feed auger 102); a gas accelerator (blower 201, see Fig. 1) configured for recirculating the pyrolysis gas that is present in the one or more reaction channels and for generating a gas flow velocity that is able to distribute the biomass in the one or more reaction channels (blower 201 provides velocity/pressure to the recycled pyrolysis gas stream coming from demister 405 such that it can be fed back to the reactor and provide a fluidized/entrained bed, see page 24 2nd full paragraph) ; a carbon separator recirculating pyrolysis gas to a gas preheater (preheater 202) from a top of the carbon separator (see separator 206 which separates a gas stream from a solid stream, where the gas stream 207 comes out of the top). Piskorz, however, does not explicitly teach a plurality of nozzles provided in the heating circuit. Coates also discloses a pyrolysis system (see abstract). Coates, like Piskorz, teaches a heated reaction chamber (1) and teaches that the heat is generated by combustion of a gas stream (via burners 2 in heating circuit 7). Coates goes on to teach that the heating circuit (7) is situated with a plurality of nozzles/burners to heat the reactor in a uniform manner (see paragraphs 50, 53, 54 and claim 19). As such, it would have been obvious to one of ordinary skill in the art at the time of the invention to add the plurality of nozzles of Coates to the heating circuit of Piskorz in order to provide a more uniform heating surface and avoid the generation of hot zones and cold zones. Regarding claim 2, Piskorz further discloses the heating circuit is configured to carry out heating by burning gas (via combustor 203). Regarding claim 3, Piskorz further discloses an oxygen minimizing device in fluid communication with the feed section, wherein the oxygen minimizing device is configured to keep an oxygen concentration of air, which is fed together with the biomass into the one or more reaction channels via the feed section, below a predefined level (see page 26, 2nd full paragraph which states that a limited amount of oxygen is added to the feed stream which suggests a controlled amount). Regarding claim 4, Piskorz further discloses the oxygen minimizing device is in fluid communication with a pipe that receives flue gas from the heating circuit (see page 26, 2nd full paragraph which states that air is added to stream 304, which is a flue gas stream from combustor 203 and which is then added to a space which is in fluid communication with the feed section). Regarding claim 5, Piskorz further discloses the oxygen minimizing device is connected to or integrated in a feed system configured for feeding the biomass into the one or more reaction channels (the oxygen minimizing device, feed stream 304, as described above, is connected to the feed system), the feed system comprising: a silo (hopper 101) for receiving, storing and supplying biomass; a metering screw mounted rotatably in a first screw channel (screw feeder that is upstream of screw feeder 102, see Fig. 2); and a feed screw mounted rotatably in a second screw channel (screw feeder 102); wherein the feed system is pressurizable (see claim 6 of Piskorz which discloses a pressure of upwards of 100kPa gauge which would require a pressurized feed system to allow for transfer of material into the reactor). Regarding claim 6, Piskorz further discloses wherein the one or more reaction channels comprise one or more ejection sections configured to release a portion of the pyrolysis gas when a gas pressure exceeds a predefined level (claimed this way, Applicant is not claiming any structure to the claimed “ejection section” other than stating that it allows flow when a pressure is above a certain level… in Piskorz, flow out of the reactor (via conduit 207) will not happen unless the pressure in the reactor is above the pressure of the downstream equipment). Regarding claim 7, Piskorz further discloses the gas accelerator is a blower (fan 201) mounted and configured for providing a gas flow velocity that disperses the biomass in the one or more reaction channels (the fan provides velocity to fluidize/disperse the bed particles). Relevant Prior Art US 2012/0063965 – Discloses a pyrolysis system that includes a gas accelerator, a feed section, a reaction channel and a heating channel but is silent re: the carbon separator that recirculates pyrolysis gas to a preheater. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to MATTHEW J MERKLING whose telephone number is (571)272-9813. The examiner can normally be reached Monday - Thursday 8am-6pm. 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, Basia Ridley can be reached at 571-272-1453. 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. /MATTHEW J MERKLING/Primary Examiner, Art Unit 1725
Read full office action

Prosecution Timeline

Apr 26, 2023
Application Filed
Apr 01, 2026
Non-Final Rejection mailed — §103, §112 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12640387
FUEL CELL SYSTEM
3y 7m to grant Granted May 26, 2026
Patent 12640424
BATTERY PACK AND ELECTRIC VEHICLE
3y 6m to grant Granted May 26, 2026
Patent 12633614
REMOTE CONTROLLER BACK SHELL
3y 1m to grant Granted May 19, 2026
Patent 12626946
PROTECTIVE LAYER FOR AN ELECTROLYTE IN A FLOW BATTERY
3y 8m to grant Granted May 12, 2026
Patent 12624302
METHOD AND REACTOR FOR PROCESSING A GAS
3y 3m to grant Granted May 12, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

Strategy Recommendation AI-generated — please review before filing

Get a prosecution strategy drawn from examiner precedents, rejection analysis, and claim mapping.
Typically takes 5-10 seconds — AI-generated, attorney review required before filing

Prosecution Projections

1-2
Expected OA Rounds
68%
Grant Probability
81%
With Interview (+13.0%)
3y 1m (~0m remaining)
Median Time to Grant
Low
PTA Risk
Based on 1262 resolved cases by this examiner. Grant probability derived from career allowance rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month