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The rejection of claims 1-10 under 35 USC § 102(a)(a) anticipated by Van der Ree is withdrawn by the examiner in view of the amendment filed on 5/1/2026.
A new Final Office Action is follows.
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 1-10 are rejected under 35 U.S.C. §103 as being unpatentable over Van der Ree et al. (US 2018/0010050 A1) in view of Gephart et al. (US 2015/0080624 A1).
Regarding independent claim 1, Van der Ree teaches a chemical recycling process comprising pyrolyzing waste plastic in a cracking reactor to thereby provide a pyrolysis effluent, wherein reusable plastic materials are heated in first and second heating devices upstream of the cracking reactor using thermal oil heat exchange systems (¶¶ [0020]-[0025], [0038], [0043]-[0046], [0063]-[0064]). Van der Ree further teaches that short-chain hydrocarbons and uncondensed gases (C1–C4) derived from the cracking reactor are used “as fuel for heating the thermal oil” (¶¶ [0024], [0035], [0041]). Van der Ree additionally teaches heating waste plastic upstream of the cracking reactor using heated thermal oil in first and second tube heat exchangers (¶¶ [0031], [0038], [0044]-[0046], [0061]-[0064]).
Van der Ree does not expressly teach that the heating of the non-aqueous HTM occurs specifically “via heat recovery from” the pyrolysis effluent as recited.
Gephart teaches recovery and reuse of heat value from pyrolysis-derived gaseous streams, including that volatile organic components and non-condensable gases generated during pyrolysis are thermally oxidized while “recovering the heat value and recirculating the heat into the jackets of the pyrolysis reactor” (¶ [0014]), and further teaches recovering heat value from non-condensable gases for heating the pyrolysis reactor (¶ [0016]). Gephart additionally teaches improved utilization of recycled heat energy within the pyrolysis process (¶ [0025]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the Van der Ree process to recover thermal energy from pyrolysis-effluent streams, including pyrolysis-derived gaseous streams, for heating the thermal oil heat transfer medium as taught by Gephart in order to conserve energy, improve thermal efficiency, and reduce external fuel consumption in the pyrolysis process.
Regarding claim 2, Van der Ree teaches at least partially liquefying waste plastic in an upstream extruder and heating device prior to introduction into the cracking reactor using indirect heat exchange with thermal oil heat exchangers (¶¶ [0021]-[0022], [0031], [0038], [0044]-[0046], [0061]-[0064]).
Regarding claim 3, Van der Ree teaches that the pyrolysis effluent comprises pyrolysis oil and pyrolysis gas fractions, including diesel product, light boilers, and uncondensed gases derived from the cracking reactor (¶¶ [0023]-[0024], [0035], [0040]-[0041], [0053]-[0055]).
Regarding claim 4, Van der Ree expressly teaches thermal oil as the heat transfer medium (¶¶ [0024], [0031], [0038], [0044]-[0046], [0050], [0061]-[0063]).
Regarding claim 5, Van der Ree teaches heating reusable plastic materials to approximately 380–400°C using thermal oil heat exchangers (¶¶ [0021]-[0023], [0063]-[0064]), thereby teaching a heated HTM temperature of at least 300°C.
Regarding independent claim 6, Van der Ree teaches heating reusable plastic materials using tube heat exchangers flushed with thermal oil, thereby teaching indirect heat exchange between the HTM and the waste plastic stream (¶¶ [0038], [0044]-[0046], [0063]-[0064]). Van der Ree further teaches use of pyrolysis-derived gaseous streams as fuel for heating the thermal oil (¶¶ [0024], [0035], [0041]). Gephart teaches recovering heat value from pyrolysis-derived gaseous streams and recirculating the recovered heat into reactor heating systems (¶¶ [0014], [0016], [0025]). It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to employ indirect heat exchange using recovered thermal energy from pyrolysis effluent streams in the Van der Ree process for the reasons set forth above.
Regarding claim 7, Van der Ree teaches upstream liquefaction and melting of reusable plastic materials in indirectly heated thermal oil heat exchangers prior to introduction into the cracking reactor (¶¶ [0021]-[0022], [0031], [0038], [0044]-[0046], [0061]-[0064]).
Regarding claim 8, Van der Ree teaches that the pyrolysis effluent includes both gaseous and liquid hydrocarbon fractions, including diesel product, light boilers, and uncondensed gases (¶¶ [0023]-[0024], [0035], [0040]-[0041], [0053]-[0055]).
Regarding claim 9, Van der Ree expressly teaches thermal oil as the non-aqueous HTM (¶¶ [0024], [0031], [0038], [0044]-[0046], [0050], [0061]-[0063]).
Regarding claim 10, Van der Ree teaches heating operations using thermal oil heat exchangers at temperatures of approximately 380–400°C (¶¶ [0021]-[0023], [0063]-[0064]), thereby teaching a heated HTM temperature of at least 300°C.
Response to Arguments
Applicant argues that Van der Ree merely combusts pyrolysis gases in a burner and therefore does not disclose “heat recovery” is not persuasive. Van der Ree expressly teaches reuse of energy originating from pyrolysis effluent streams to heat thermal oil used in upstream process heating operations. The claims do not require any particular type of heat recovery equipment such as a heat recovery steam generator, recuperator, or economizer, nor do the claims exclude combustion-assisted recovery of thermal energy from pyrolysis-derived gases.
Moreover, Gephart expressly teaches recovery and recirculation of heat value from pyrolysis-derived process streams. Specifically, Gephart teaches that volatile organic components and non-condensable gases generated during pyrolysis are thermally oxidized while “recovering the heat value and recirculating the heat into the jackets of the pyrolysis reactor” and further teaches that non-condensable gases are treated “to recover the heat value for heating the pyrolysis reactor.” Gephart additionally teaches improved utilization of recycled heat energy within the pyrolysis system. Accordingly, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to recover thermal energy from pyrolysis effluent streams, including pyrolysis-derived gaseous streams, and use the recovered energy to heat a non-aqueous HTM for upstream heating operations in order to conserve energy, improve thermal efficiency, and reduce external fuel requirements.
With respect to amended independent claim 6, Van der Ree already teaches indirect heat exchange through tube heat exchangers flushed with thermal oil. Gephart likewise teaches indirectly heated pyrolysis systems and reactor jackets for transferring recovered heat. Therefore, the combination teaches or at least renders obvious heating a non-aqueous HTM via indirect heat exchange using heat recovered from pyrolysis effluent.
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 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
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