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
Amendment to claims 1, 2 and 23; and cancelation of claims 4, 5, 9 and 16 are noted.
The reply overcomes the claim rejections under 35 USC 112(b).
Due to amendments to the claims, the previous prior art rejections are modified herein.
Response to Arguments
Applicant's arguments filed 30 December 2025 have been fully considered but they are not persuasive.
Applicant argues that the low temperature claimed is important to ensure negligible cracking where Mennell discloses temperatures upwards of 2000°C in various reactors.
This argument is not found persuasive. The office acknowledges that Mennell discloses reactors with high operating temperatures, including up to 2000°C as stated by Applicant. However, these higher temperatures occur in reactors downstream of the twin screw reactor. The first reactor (twin screw conveyor) operates at a temperature in between 300 and 700°C (see [0214]), which overlaps the claimed range. Applicant has not established criticality associated with the claimed range, i.e., where temperatures between 450 and 700°C as in the upper range of Mennell’s disclosure, for example, are disadvantageous.
Applicant further argues that the combination of the twin screw conveyor through which heat transfer fluid is passed with the low temperature reaction yields a carbon product which is ideal for carbon capture and achieving high carbon credits.
This argument is not found persuasive. The combination of references is considered to fully teach and/or suggest the claimed limitations. The fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
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, 6-8, 10-15, 23-27, 37 and 38 are rejected under 35 U.S.C. 103 as being unpatentable over Mennell et al (US 2022/0162726) in view of Tenore et al (US 2020/0369964) and McCabe et al (US 5,216,821).
Regarding claims 1, 6, 7, 10 and 11, Mennell discloses a process for converting biomass waste to a solid carbon product, comprising (see [0006]-[0007]; [0179]):
passing the biomass waste into a reactor comprising a twin screw conveyor (see [0042]; [0564]);
heating the reactor at a temperature of about 300 to 700°C, overlapping the claimed ranges (see [0011]; [0214]);
passing the biomass waste with heating and mixing along the length of the reactor (see [0554]); and
collecting a solid carbon product from the reactor (see [0073]; [0171]).
Mennell does not disclose a twin screw conveyor having the claimed configuration.
Tenore discloses a twin screw conveyor reactor comprising twin screws with cuts and folds, specifically comprising augers with a right hand cut and folded flighting. This design of the screw conveyors facilitates continuous wiping of product from the wall and moves it downstream through the reactor (i.e., flighting acts as fingers as claimed) (see Figs. 9 & 21; [0172]; [0175]).
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 Mennell by using a twin screw conveyor configuration as disclosed in Tenore in order to ensure sufficient movement of solid product through and out of the reactor chamber.
Mennell further does not disclose wherein heat transfer fluid is passed internally through the twin screws of the twin screw conveyor.
McCabe discloses that screw conveyors may be heated by directing a heat transfer medium into a conduit of the screw conveyor (see Abstract).
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 Mennell by implementing screws in the reactor through which heat transfer medium can flow, as suggested by McCabe, in order to enhance the heating capabilities of the reaction system.
Regarding claim 8, Mennell in view of Tenore does not explicitly disclose wherein the material is conveyed from 6 o’clock on the flight face to above 2 o’clock. Nevertheless, it is considered that a person of ordinary skill in the art would determine by routine experimentation the optimum design and operation of the conveyor screws which achieves the objective of adequately moving solids through the reactor chamber, thus avoiding or minimizing plugging and shutdown time. Absent a showing of criticality or unexpected results, the claimed design is not considered to patentably distinguish the instant claims over the cited art.
Regarding claim 12, Mennell discloses a reaction time of from 10 seconds to about 24 hours (see [0214]), overlapping the claimed range.
Regarding claim 13, Mennell discloses wherein the reactor is heated by one or more burners (see [0186]-[0187]; [0557]).
Regarding claim 14, Mennell does not explicitly disclose wherein the burner(s) heat the reactor from the bottom. However, recitation of such in the claims is not considered to patentably distinguish the instant claims over the cited prior art. A person of ordinary skill in the art would determine, by routine experimentation, suitable areas to provide heat to the reactor which achieves the desired degree of heating and reaction of the biomass therein. The location of heating provided to the reactor is a matter of design choice for a person of ordinary skill in the art.
Regarding claim 15, Mennell discloses wherein the burner(s) combust gases created during the heating of the biomass (see [0186]-[0187]).
Regarding claim 23, Mennell discloses wherein a portion of exhaust biomass gases are removed from the reactor and stored (i.e., in oxidizing reactor) (see [0018]; [0049]).
Regarding claims 24 and 25, Mennell discloses wherein the stored gases are used to start a reaction in the reactor and to supplement the heating of the reactor (see [0186]-[0187]).
Regarding claims 26 and 27, Mennell discloses wherein a portion of exhaust biomass gases are removed from the reactor and stored in a container containing charcoal recovered from a reaction (i.e., in reducing gas production reactor) (see Fig. 1; [0157]; [0159]).
Regarding claims 37 and 38, Mennell discloses carrying out the process in batch mode or continuous mode (see [0486]).
Claims 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Mennell in view of Tenore and McCabe, as applied to the claims above, in further view of Randazzo et al (US 2021/0388271).
Regarding claims 2 and 3, Mennell does not disclose a secondary volume around the reactor for a heat transfer fluid.
Randazzo discloses heating a reactor comprising a screw conveyor with the passage of molten salts in a jacket positioned on the outside of the reaction chamber which envelopes the whole reactor (see [0021]-[0023]; [0119]). Preferred molten salts is a mixture of sodium nitrate and potassium nitrate (i.e., solar salt composition) (see [0144]). Randazzo discloses that the heating jacket construction ensures necessary supply of heat to the reactor and guarantees homogenous distribution of the flow of molten salts for maximizing the thermal exchange coefficient (see [0143]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to further modify the process of Mennell by using a reactor jacket configuration through which molten salts flow, as suggested by Randazzo, in order to heat the reactor in a manner that maximizes the thermal exchange coefficient.
Claims 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Mennell in view of Tenore and McCabe, as applied to the claims above, in further view of Garjian (US 10,465,120).
Regarding claim 17, 19 and 20, while Mennell discloses that pyrolysis is performed in the absence of oxygen (see [0121]), the reference does not explicitly disclose wherein the reactor is sealed from outside air.
Garjian discloses sealing a screw conveyor reactor by use of valve airlocks, including rotary valves (see col. 2, line 61 – col. 3, line 24).
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 Mennell by using a reactor comprising valve airlocks, as suggested by Garjian, in order to seal the reactor and ensure an oxygen-free environment.
Regarding claim 18, Mennell discloses wherein the reactor is nitrogen purged (see [0492]; [0842]).
Claims 21 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Mennell in view of Tenore, McCabe, and Garjian, as applied to the claims above, in further view of Kretschmer et al (US 2012/0266966).
Regarding claims 21 and 22, Garjian discloses valves including rotary valves and other mechanisms which do not comprise hermeticity (see col. 3, lines 8-24), but does not explicitly disclose butterfly valves.
In this regard, reference is drawn to Kretschmer, which discloses that both rotary valves and butterfly valves are useful as airlocks (see [0037]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to select rotary valves, butterfly valves, and combinations thereof for use in the process of Mennell, in order to maintain an airtight seal and an oxygen-free environment for the pyrolysis reaction.
Claims 28 and 29 are rejected under 35 U.S.C. 103 as being unpatentable over Mennell in view of Tenore and McCabe, as applied to the claims above, in further view of Lepez et al (US 2018/0134963).
Regarding claims 28 and 29, Mennell does not disclose wherein the twin screws are solid metal rods and the body of the reactor comprises stainless steel.
Lepez discloses that stainless steel is a suitable material for constructing both a reactor body and screw component of a conveyor screw reactor because it is able to withstand high temperatures (see [0040]; [0049]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to further modify the process of Mennell by using a reactor and screw therein constructed from stainless steel, as suggested by Lepez, given that it is a material known to be suitable for the purpose based on its ability to withstand high temperatures.
Claims 30 and 31 are rejected under 35 U.S.C. 103 as being unpatentable over Mennell in view of Tenore and McCabe, as applied to the claims above, in further view of Vanttinen et al (US 2016/0326439).
Regarding claims 30 and 31, Mennell does not disclose wherein the reactor is insulated.
Vanttinen discloses thermally insulating a screw-type pyrolysis reactor by coating it with ceramic wool (see [0023]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to further modify the process of Mennell by using a reactor insulated with ceramic wool, as suggested by Vanttinen, in order to prevent heat from escaping the reactor.
Claims 32-35 are rejected under 35 U.S.C. 103 as being unpatentable over Mennell in view of Tenore, McCabe, and Vanttinen, as applied to the claims above, in further view of Muth (US 6,155,215).
Regarding claim 32, Mennell does not disclose wherein thermal breaks are provided between the reactor and one or more valves.
Muth discloses implementing thermal breaks around valves in order to prevent heat transfer through the valve (see col. 8, lines 56-60).
It would have been obvious to a person of ordinary skill in the art at the time of fling the instant claimed invention to further modify the process of Mennell by implementing thermal breaks around valves in the system, as suggested by Muth, in order to prevent heat transfer through the valve.
Regarding claim 33, the shape of the thermal breaks is a matter of design choice and is not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claims 34 and 35, Vanttinen discloses insulation with ceramic wool, as discussed above. Applying such insulation to the thermal breaks would have been obvious to a person of ordinary skill in the art for the same reason of preventing heat from escaping the system.
Claim 36 is rejected under 35 U.S.C. 103 as being unpatentable over Mennell in view of Tenore and McCabe, as applied to the claims above, in further view of Kung et al (US 2021/0087487).
Regarding claim 36, Mennell does not disclose wherein the solid carbon product is buried underground and covered.
Kung is directed to decomposition of biomass (see Abstract). Inert biochar is a product and can be buried underground as a means of CO2 sequestration (see [0303]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to further modify the process of Mennell by burying the solid carbon product, as suggested by Kung, as a means of CO2 sequestration.
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