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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 2 February 2026 has been entered.
Response to Arguments
Applicant's arguments filed 2 February 2026 have been fully considered but they are not persuasive.
Applicant is of the position that the combination of references would not lead a person of ordinary skill in the art to realize the combination of features recited by claim 1 because the proposed modification changes the principle of operation of the Graziani (primary) reference.
The office respectfully disagrees and maintains the position taken in the final office action (FOA) mailed 07 October 2025 and the advisory action (AA) mailed 15 January 2026, namely that the feeding of the dissolved plastic through the fractionator is not necessarily an essential aspect of Graziani, such that introduction of dissolved plastic to the coker drum itself, as in the proposed modification, would materially change the principle of operation of Graziani. As noted therein, Graziani also discloses that plastics which are sufficiently soluble in the extract phase can be fed directly to the coker (FOA, par. 6). Furthermore, Volk is considered to provide the motivation for a person of ordinary skill in the art to modify Graziani by implementing injection of anti-foaming agent through a nozzle near the top of the coker drum ( FOA, par. 7-8, 13-14). Therefore, the office is of the position that the combination of references is proper.
The office further notes that the proposed modification does not necessarily mean that the dissolved plastic mixture in Graziani may not be introduced at other locations as disclosed within the reference, but is, at the very least, additive, i.e., based on the suggestions of Volk, a person of ordinary skill would be motivated to modify Graziani to include injection of the plastic mixture into the top of the coke drum in order to control foam levels and manipulate the formation of coke (FOA, par. 14).
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, 2 and 6-12 are rejected under 35 U.S.C. 103 as being unpatentable over Graziani et al (WO 95/14069) in view of Volk, JR. (US 2010/0300940).
Regarding claims 1 and 11, Graziani discloses a method of reducing foaming within a coke drum of a delayed coking unit comprising (see p. 9, lines 11-33):
forming a plastic mixture including a plastic material and a carrier (solvent), wherein the plastic material includes one or more of: polyethylene, polypropylene, polystyrene and polyester (see p. 7, lines 20-35; p. 9, lines 4-13); and
injecting the plastic mixture into the coke drum during operation of the coke drum (see p. 5, lines 3-12; p. 9, lines 11-15).
Graziani does not disclose wherein injecting includes dispensing the plastic mixture on top of foam occurring within the coke drum.
Volk discloses injecting anti-foaming agent through a nozzle near the top of the coker drum to control foam levels and manipulate the formation of coke. The injection occurs on top of foam within the drum (see [0022]; [0024]).
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 Graziani by injecting the plastic mixture (i.e., anti-foaming agent) into the top of the coke drum, above foam occurring therein, as suggested by Volk, in order to control foam levels and manipulate the formation of coke.
Regarding claim 2, Graziani discloses wherein forming the plastic mixture comprises at least partially dissolving the plastic material in the carrier (see p. 5, lines 3-7).
Regarding claim 6, Graziani discloses wherein the plastic material includes one or more of a recycled plastic material or a post-consumer plastic material (see Abstract, plastic waste).
Regarding claim 7, Graziani discloses wherein the carrier includes a hydrocarbon carrier (see Table 1).
Regarding claim 8, Graziani discloses wherein the carrier includes one or more of: heavy coker gas oil, FCC slurry oil, and decant oil (see Table 1).
Regarding claim 9, Graziani discloses wherein forming the plastic mixture includes temperature controlling the carrier to an elevated temperature (see p. 14, lines 1-9).
Regarding claim 10, Graziani does not explicitly disclose the concentration of plastic material in the mixture. However, Graziani discloses mixing such that a substantial amount of the plastic is dissolved, suspended, and/or dispersed within the carrier (see p. 14, lines 1-4). Determining a suitable concentration which achieves the stated objective would be obvious to and require nothing more than routine experimentation for a person of ordinary art. Absent a showing of criticality or unexpected results, the claimed concentration is not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claim 12, Graziani does not disclose the concentration at which the combined plastic material and carrier is injected into the coke drum, with respect to the total coker feedstock. However, Graziani discloses that injection of the plastic mixture produces a superior product and reduced foaming in comparison to operation of the delayed coker in the absence of the plastic mixture (see p. 9, lines 11-33). A person of ordinary skill in the art would optimize, by routine experimentation, the concentration at which the plastic mixture is injected in order to achieve the stated objectives. Absent a showing of criticality or unexpected results, the claimed concentration of plastic mixture is not considered to patentably distinguish the instant claims over the cited prior art.
Claims 3, 13-15 and 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Graziani in view of Volk, as applied to the claims above, in further view of Esselbrugge et al (US 2004/0176259).
Regarding claim 3, Graziani does not disclose wherein forming the plastic mixture comprises combining the plastic material and the carrier using a high-shear mixer.
However, insofar as it is well-known in the art to prepare stable foam control compositions using high-shear mixers with rotor blades (see Esselbrugge: [0021]), use of such in the process of Graziani would have been obvious to a person of ordinary skill in the art and associated with at least a reasonable expectation of success.
Regarding claims 13 and 20, Graziani discloses a method of reducing foaming within a coke drum of a delayed coking unit comprising (see p. 9, lines 11-33):
providing a plastic material, wherein the plastic material includes one or more of polyethylene, polypropylene, polystyrene, or polyester (see p. 9, lines 4-13);
providing a carrier (solvent) (see p. 9, lines 4-13);
combining the plastic material and the carrier to at least partially dissolve the plastic material in the carrier (seep. 5, lines 3-7; p. 7, lines 20-35); and
injecting the combined plastic material and carrier into the coke drum during thermal cracking of a coker feedstock (see p. 5, lines 3-12; p. 9, lines 11-15; p. 15, line 35 – p. 16, line 2).
Graziani does not disclose wherein: (1) forming the plastic mixture comprises combining the plastic material and the carrier using a high-shear mixer; and (2) injecting the combined plastic material includes dispensing the plastic mixture on top of foam occurring within the coke drum.
However, regarding (1), insofar as it is well-known in the art to prepare stable foam control compositions using high-shear mixers with rotor blades (see Esselbrugge: [0021]), use of such in the process of Graziani would have been obvious to a person of ordinary skill in the art and associated with at least a reasonable expectation of success.
Regarding (2), Volk discloses injecting anti-foaming agent through a nozzle near the top of the coker drum to control foam levels and manipulate the formation of coke. The injection occurs on top of foam within the drum (see [0022]; [0024]).
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 Graziani by injecting the plastic mixture (i.e., anti-foaming agent) into the top of the coke drum, above foam occurring therein, as suggested by Volk, in order to control foam levels and manipulate the formation of coke.
Regarding claim 14, Graziani discloses heating the carrier to a temperature of 50 to 600°F (see p. 14, lines 5-9), overlapping the claimed range.
Regarding claim 15, Graziani discloses wherein heating is done during the mixing of the plastic material and the carrier (see p. 14, lines 1-9).
Regarding claim 17, Graziani discloses wherein the carrier includes one or more of: heavy coker gas oil, FCC slurry oil, and decant oil (see Table 1).
Regarding claim 18, Graziani does not explicitly disclose the concentration of plastic material in the mixture. However, Graziani discloses mixing such that a substantial amount of the plastic is dissolved, suspended, and/or dispersed within the carrier (see p. 14, lines 1-4). Determining a suitable concentration which achieves the stated objective would be obvious to and require nothing more than routine experimentation for a person of ordinary art. Absent a showing of criticality or unexpected results, the claimed concentration is not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claim 19, Graziani does not disclose the concentration at which the combined plastic material and carrier is injected into the coke drum, with respect to the total coker feedstock. However, Graziani discloses that injection of the plastic mixture produces a superior product and reduced foaming in comparison to operation of the delayed coker in the absence of the plastic mixture (see p. 9, lines 11-33). A person of ordinary skill in the art would optimize, by routine experimentation, the concentration at which the plastic mixture is injected in order to achieve the stated objectives. Absent a showing of criticality or unexpected results, the claimed concentration of plastic mixture is not considered to patentably distinguish the instant claims over the cited prior art.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Graziani in view of Volk and Esselbrugge, as applied to the claims above, in further view of Bush et al (US 2007/0008812).
Regarding claim 4, Graziani in view of Volk and Esselbrugge does not disclose wherein the high-shear mixer includes a slotted rotor/stator high-shear mixer.
Bush is directed to a mixing process for producing a mixture from a solids component and a liquid component (see Abstract). In particular, Bush discloses use of a high-shear mixer having a slotted rotor/stator which is capable of achieving a homogenous mixture (see [0011]).
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 Graziani in view of Volk and Esselbrugge by using a high-shear mixer having a slotted rotor/stator, as suggested by Bush, in order to ensure formation of a homogenous plastic mixture.
Conclusion
All claims are identical to or patentably indistinct from, or have unity of invention with claims in the application prior to the entry of the submission under 37 CFR 1.114 (that is, restriction (including a lack of unity of invention) would not be proper) and all claims could have been finally rejected on the grounds and art of record in the next Office action if they had been entered in the application prior to entry under 37 CFR 1.114. Accordingly, THIS ACTION IS MADE FINAL even though it is a first action after the filing of a request for continued examination and the submission under 37 CFR 1.114. See MPEP § 706.07(b). 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