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
Amendments to the drawings and to claims 1, 4, 6, 7, 13, 14, 16 and 17 are noted.
The amendments overcome the drawing objection, claim objections, and claim rejections under 35 USC 112(b) and (d).
Due to amendments to the claims, the previous prior art rejections are modified herein.
Response to Arguments
Applicant's arguments filed 15 July 2026 have been fully considered but they are not persuasive.
Applicant argues that amended claim 1 requires that “heat from the fluid energy source is transferred to the initial stream through a heat transfer medium loop” and, by contrast, the cited passage of Grispin describes the hot flue gas itself flowing through the system then out of the system.
This argument is not found persuasive. Grispin’s flow of flue gas through the system, including its use for preheating incoming plastic waste material, is considered to fully read on the scope implied by the claim language as currently presented. There are no additional defining details or limitations which distinguish the claimed “heat transfer medium loop” from the embodiment disclosed in Grispin. In this respect, Applicant appears to be applying an overly narrow interpretation of the claims.
Applicant argues that the office action does not identify any disclosure in Grispin of a separate heat transfer medium, a loop carrying that heat transfer medium, or transfer of heat from the flue gas to the initial stream through such loop.
This argument is not found persuasive. The office respectfully reiterates that Applicant appears to be applying an overly narrow interpretation of the claims. The claims do not require a “separate heat transfer medium.” The office maintains that Grispin’s flue gas flow configuration is considered to read on the claimed embodiment for the reasons outlined in the previous office action and below in the current office action, updated to reflect the claim amendments.
Applicant argues that the office action does not explain how Grispin’s hot flue gas constitutes the claimed “waste stream that is undergoing or otherwise subject to exhaustion from a chemical recycling plant.” Applicant contends that the fact that Grispin’s flue gas ultimately exits the apparatus after flowing through the system does not itself teach the claimed use of an exhaust-bound waste stream “as a recoverable fluid energy source whose heat is transferred to an initial stream through a heat transfer medium loop.”
The office respectfully disagrees. Instant claim 10 explicitly discloses that the fluid energy source is a flue gas. Thus, Grispin’s flue gas is considered to teach the claimed fluid energy source. Furthermore, the office respectfully submits that flue gases are well known in the art to be waste gases and Grispin’s process flow clearly shows exhaust of the flue gas from the system (see Fig. 1).
Applicant further argues that (1) there is no articulated reason why a person of ordinary skill would have modified Grispin’s disclosed flue gas flow arrangement to include a distinct heat transfer medium loop; and (2) the office action appears to rely on impermissible generalization that because Grispin discloses heating in a pyrolysis process, Grispin renders obvious any heat source or heat transfer configuration associated with chemical recycling.
These arguments are not found persuasive. The office maintains that Grispin is considered to fully teach the claimed preheating with a fluid energy source. The claims, as currently presented, do not require “a distinct heat transfer medium loop” which is in any way distinguished from the flow of flue gas in Grispin, as discussed above. Finally, the office has taken no such position that Grispin renders obvious “any heat source or heat transfer configuration with chemical recycling;” rather, the position is that Grispin’s flow configuration of flue gas through the system to heat the incoming material reads on the scope of the claim, as presented. The office notes that only one of the alternatives listed in claim 1 is required. Grispin’s teaching of a flue gas to heat the waste plastic connected to the liquefying step fully teaches the claimed embodiment. Applicant has not sufficiently pointed out why or how they consider Grispin’s configuration to be deficient as it relates to the claimed embodiment.
In response to Applicant’s argument that a proper obviousness rejection must account for the claimed invention “as a whole”, the office respectfully submits that the position taken in this and the previous office action does consider the claimed invention as a whole. Grispin is considered to fully teach and/or suggest the embodiment of claim 1 for the reasons articulated therein and outlined above in the argument responses.
Applicant argues that claim 14 requires a specific process architecture in which heat from a flue gas stream is indirectly transferred to an initial stream through a heat transfer medium loop.
In response, the office notes that a new reference is applied to claim 14 in light of the change in scope required by indirect heat exchange. This argument is therefore moot.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-10 are rejected under 35 U.S.C. 103 as being unpatentable over Grispin (US 2007/0289862).
Regarding claim 1, Grispin discloses a chemical recycling process comprising (see Fig. 1; [0001]; [0011]; [0014]):
(a) liquefying (melting) at least a portion of a waste plastic in a liquification system to form a liquefied waste plastic (see [0012]; [0024]; [0034]);
(b) pyrolyzing at least a portion of the liquefied waste plastic to produce a pyrolysis effluent (see [0034]; [0038]); and
(c) preheating at least a portion of the waste plastic subjected to the liquefying of step (a) with a fluid energy source (flue gas) (see [0032]; [0038] – “hot flue gas then flows through 16 then out 18, preheating the incoming material”).
The flue gas stream in Grispin is considered to teach the claimed waste gas stream that is undergoing or otherwise subject to exhaustion from a chemical recycling facility, as it is a waste gas produced from combusted loop gas used for the pyrolysis of the waste plastic (i.e., “chemical recycling facility”) which is undergoing exhaustion (via its flow through 16 then out 18) (see Fig. 1; [0038]). Furthermore, this flow of flue gas and its heat transfer with the initial stream (waste plastic) is considered to teach the claimed heat transfer loop (refer to Fig. 1 and the gas flow arrows from burner 51, through the space between the lower outer walled vessel 32, upper outer walled vessel 25, past the auger air lock 20, then through 16 and out 18).
Grispin does not explicitly disclose the temperature of the flue gas. However, given that the purpose of the flue gas is to provide heat to preheat the incoming feed material (see [0038]), determining the optimum temperature compatible with this objective amounts to nothing more than routine experimentation for a person of ordinary skill in the art. Absent a showing of criticality or unexpected results, the claimed temperature of the fluid energy source is not considered to patentably distinguish the instant claim over the cited prior art.
Regarding claim 2, Grispin discloses wherein the fluid energy source is exhausted after the preheating step of (c) (see Fig. 1; [0038]).
Regarding claims 3 and 4, Grispin does not explicitly disclose the enthalpy of the fluid energy source. Nevertheless, a person of ordinary skill in the art would select a suitable fluid energy source which provides thermal capabilities consistent with the objectives in Grispin, i.e., is able to provide sufficient heat to heat the reactor and the incoming feed material (see [0032]; [0038]). Absent a showing of new or unexpected results, the claimed enthalpy of the fluid energy source is not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claim 5, Grispin does not explicitly disclose the pressure of the fluid energy source. Nevertheless, a person of ordinary skill in the art would select a suitable pressure at which to provide the fluid energy source to the reactor system which is compatible with operation of the system and the flow of the flue gas therethrough. Absent a showing of unexpected results, the claimed pressure of the fluid energy source is not considered to patentably distinguish the instant claim over the cited prior art.
Regarding claims 6 and 7, the temperature of the fluid energy source is addressed in the rejection of claim 1 above, which applies equally herein.
Regarding claims 8-10, Grispin discloses wherein the flue gas is a pyrolysis reactor flue gas (see [0038]).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Grispin, as applied to the claims above, in view of Dana (US 2012/0138422).
Regarding claim 11, Grispin does not disclose wherein the fluid energy source comprises a quench stream from a quench system. It is noted, however, that Grispin discloses cooling and condensing the gaseous stream obtained from the pyrolysis reaction using “appropriate equipment” (see [0032]).
In this regard, Dana discloses that quenching is a suitable technique for cooling a reaction effluent resulting from pyrolysis (see [0048]-[0049]; [0085]). Steam generated from quenching water may be collected and used as a secondary energy source in the system (see [0096]), where energy source includes providing heat to the reactor system (see [0087]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to modify the process of Grispin by cooling the reaction effluent with quenching water to produce steam, as suggested by Dana, wherein the steam may then be used as a secondary energy source for heating the system, in order to improve the overall energy efficiency of the process.
Claims 12 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Grispin, as applied to the claims above, in view of Yamamoto (JP 2000-176403).
Yamamoto is cited from the English translation provided by Applicant.
Regarding claim 12, the flow of the flue gas through the preheating step in Grispin would necessarily entail cooling of the gas based on principles of heat exchange. However, Grispin does not disclose recovering carbon dioxide from the cooled gas (fluid energy source).
Yamamoto discloses absorbing carbon dioxide present in waste gas generated from pyrolysis of residue, including waste plastic. Removing carbon dioxide before venting is advantageous because carbon dioxide is deleterious for the environment (see Abstract; pp. 7-9)
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to modify the process of Grispin to include a step of capturing carbon dioxide from the gas prior to venting, as suggested by Yamamoto, in order to minimize environmental harm caused by the exhaust gas.
Regarding claim 13, the temperature of the cooled flue gas depends on the operating conditions within the pyrolysis system and the desired temperature to which the feed material is preheated. A person of ordinary skill in the art would determine the optimum workable temperature ranges which provide favorable conditions for the upgrading of the plastic feed material. Absent a showing of criticality or unexpected results, the claimed temperature range of the cooled flue gas is not considered to patentably distinguish the instant claimed invention over the cited prior art.
Claims 14-20 are rejected under 35 U.S.C. 103 as being unpatentable over Wang (CN 111778046) view of Yamamoto.
Wang is cited from the English machine translation, provided herewith.
Regarding claims 14, 15, 19 and 20, Wang discloses a chemical recycling process comprising (see Figs. 1-3; Abstract, recycling plastic waste):
(a) liquefying (melting) at least a portion of a waste plastic in a liquification system (melting device 3) to form a liquefied waste plastic (see; p. 2, paragraph beginning “heating and melting”)
(b) pyrolyzing 4 at least a portion of the liquefied waste plastic to produce a pyrolysis effluent (see p. 2, paragraph beginning “the molten plastic waste”); and
(c) preheating at least a portion of the waste plastic subjected to the liquefying of step (a) with a flue gas stream (see Fig. 2, flue gas inlet 33, flue gas outlet 34, material inlet 31, molten material outlet 32; paragraph bridging pp. 2-3; p. 4, paragraph beginning “In one embodiment, the high temperature”; p. 6, paragraph beginning “In the present application, the structure”).
Heat from the flue gas stream is indirectly transferred to the waste plastic stream through a heat transfer medium loop (see Figs. 1-3, in particular Fig. 2, depicting separate chambers for heating plastic material 37 and for flow of flue gas 36, i.e., indirect heat transfer).
After the preheating step, the flue gas is exhausted (see Fig. 2). The flow of the flue gas through the preheating step in Wang would necessarily entail cooling of the gas based on principles of heat exchange. However, Wang does not disclose (1) the temperature of the flue gas stream before and after preheating or (2) recovering carbon dioxide from the cooled flue gas stream.
Regarding (1), Wang discloses carrying out melting at a temperature in the range of 120-180°C (see pp. 4-5, step (2)). Thus, the temperature of the flue gas must necessarily be sufficient to provide the heat to bring the molten plastic to the recited temperature, i.e. within or overlapping the ranges of claims 19 and 20. Furthermore, the flue gas is used in a subsequent drying step and is further cooled (see p. 4, step (1)). The temperature of the cooled flue gas is reasonably expected to be as claimed or substantially overlapping (where the drying step is controlled to a temperature of 100-105°C). Determining the operating conditions consistent with the objective of heating the incoming material prior to pyrolysis amounts to nothing more than routine experimentation for a person of ordinary skill in the art and would be associated with a reasonable expectation of success. Absent a showing of criticality or unexpected results, the claimed temperatures are not considered to patentably distinguish over the cited prior art.
Regarding (2), Yamamoto discloses absorbing carbon dioxide present in waste gas generated from pyrolysis of residue, including waste plastic. Removing carbon dioxide before venting is advantageous because carbon dioxide is deleterious for the environment (see Abstract; pp. 7-9)
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to modify the process of Wang to include a step of capturing carbon dioxide from the flue gas prior to venting, as suggested by Yamamoto, in order to minimize environmental harm caused by the exhaust gas.
Regarding claims 16 and 17, Wang does not explicitly disclose the enthalpy of the flue gas stream. Nevertheless, a person of ordinary skill in the art would select a suitable flue gas composition which provides thermal capabilities consistent with the objectives in Wang, i.e., is able to provide sufficient heat to heat the reactor and the incoming feed material (see p. 4). Absent a showing of new or unexpected results, the claimed enthalpy of the flue gas stream is not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claim 18, Wang does not explicitly disclose the pressure of the flue gas stream. Nevertheless, a person of ordinary skill in the art would select a suitable pressure at which to provide the flue gas to the reactor system which is compatible with operation of the system and the flow of the flue gas therethrough. Absent a showing of unexpected results, the claimed pressure of the flue gas stream is not considered to patentably distinguish the instant claim over the cited prior art.
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 RENEE ROBINSON whose telephone number is (571)270-7371. The examiner can normally be reached Monday - Thursday 8:00a-5:00p and Friday 8:00a-2:00p.
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/Renee Robinson/Primary Examiner, Art Unit 1772
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