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 .
Response to Amendment
The rejection of claims 1-20 on the ground of nonstatutory double patenting as being unpatentable over claims 1-20 of copending Application No. 18/691,088 is withdrawn by the examiner in view of the amendment filed on 1/27/2026.
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.
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 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over Gephart et al. (US 2015/0080624 A1) in view of Wolf et al. (US 2007/0227874 A1).
Gephart discloses:
a liquification vessel (melt screw reactor 2) for liquefying solid plastic (¶¶13, 20, 32);
a pyrolysis reactor 4 for pyrolyzing the liquefied plastic to generate a pyrolysis vapor/effluent (¶¶13, 31–32, 45);
multiple condensation steps (3 condensers: condensers 9, 11, 13) producing multiple oil streams (heavy, middle, light fractions) (¶¶25-35, 40–48; 51–53);
indirect heat exchange of the pyrolysis effluent with a heat transfer medium (HTM) in the first condenser (heat-transfer oil) to generate heated HTM (¶41);
using the heated HTM to heat solid plastic upstream in the dryer (¶41; 51) and to heat liquefied plastic upstream via the hot-oil-heated melt screw and pump screw (¶¶45, 61).
Thus, Gephart teaches all elements of claim 1 except, at most, the specific degree of heat-integration and distribution of HTM throughout multiple circuits.
Wolf teaches:
a multi-circuit indirect heating system using oil/salt/gas HTMs (¶¶7, 17, 44) and employing five discrete heat-transfer medium circuits (WT1-WT5) ((¶¶ 46).
recovering heat from multiple condensers (pre-condenser and main condenser) and returning it to HTM circuits (¶¶8–10, 36, 46);
using heated HTM to heat solid plastic (melting tank) and liquefied plastic (evaporation/re-heating tanks) upstream of cracking/pyrolysis (¶¶7, 17, 31–35, 46–49);
multi-stage condensation (¶¶6, 10, 13, 36–37).
Both references teaches new limitations “at least 3 condensation steps” whereas Wolf expressly teaches five discrete HTM circuits.
The claimed limitations requiring “not more than 100 heat transfer medium loops” does not distinguish over the combined prior art, because Wolf’s five HTM loops (¶¶ 46) fall within the claimed upper bound.
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Gephart by incorporating Wolf’s well-known multi-circuit HTM and energy-recuperation techniques into Gephart’s pyrolysis system to improve energy efficiency and reduce external utility load, consistent with Wolf’s explicit motivation (¶¶5, 7–10). Claims 2–3: Gephart teaches heating solid and liquefied plastic upstream using heated HTM (¶¶41, 45, 61); Wolf confirms such heat distribution.
Claims 4–5: Gephart teaches ≥3 condensation steps (condensers 9, 11, 13) and indirect heat exchange via HTM (¶¶40–43, 51–53).
Claim 6: Re-processing pyrolysis oil in a cracking facility is conventional; Wolf explicitly discloses cracking tower and downstream oil handling.
Claims 7–9: HTM compositions (aqueous, non-aqueous, oil, salt, molten media) taught by Wolf (¶7; 44).
Claim 10: Gephart inherently operates HTM above 270 °C (¶¶41, 61–63).
Claim 11: Wolf teaches multiple independent HTM circuits (WT1–WT5), each using oil/salt/gas and providing heat at different temperature levels (¶¶7, 44, 46). See claim 1 above.
Claims 12–13: Upstream heating via first/second HTM rendered obvious by Wolf’s multiple circuits.
Claims 14–15: Gephart teaches ≥3 condensation steps; Wolf teaches integration of condensers with multiple HTMs.
Claim 16: Sending pyrolysis oil to cracking is disclosed by Wolf’s cracking tower.
Claims 17–19: Wolf expressly teaches aqueous and non-aqueous HTMs including oils, salts, molten media (¶7; 44).
Claim 20: Temperature thresholds inherent in high-temperature HTM circuits in Gephart and Wolf (≥300 °C, ≥270 °C).
Response to Arguments
The argument that both Gephart and Wolf do not teach "wherein the multiple condensation steps comprise at least 3 and not more than 100 heat transfer medium loops with each loop comprising its own heat transfer medium" is not persuasive because the combined teachings of Gephart and Wolf render obvious:
• at least 3 condensation steps, as both references disclose multi-stage condensation of pyrolysis vapors, and• a plurality of HTM loops, as Wolf expressly teaches five discrete HTM circuits.
The claimed limitation requiring “not more than 100 heat transfer medium loops” does not distinguish over the combined references, because Wolf’s five HTM loops fall within the claimed upper bound.
Conclusion
THIS ACTION IS MADE FINAL. 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 TAM M NGUYEN whose telephone number is (571)272-1452. The examiner can normally be reached Mon - Frid.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Prem C Singh can be reached at 571-273-6381. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/TAM M NGUYEN/Primary Examiner, Art Unit 1771