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 .
Remarks
The amendments and remarks filed on 12/04/2025 have been entered and considered. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior office action. The rejections and/or objections presented herein are the only rejections and/or objections currently outstanding. Any previously presented objections or rejections that are not presented in this Office Action are withdrawn. Claims 1-7, 12-17, and 20-24 are pending; Claims 8-11, 18-19, and 25-26 are cancelled; Claims 1, 5, 20, and 23 are amended; and Claims 1-7, 12-17, and 20-24 are under examination.
Withdrawal of Rejections
The rejection of Claim 11 under 35 U.S.C. 112(d) is withdrawn due to the cancellation of the claim.
The rejection of claims 11 and 26 under 35 U.S.C. 112(b) is withdrawn due to the cancellation of the claims.
Claim Objections
Claim 23 is objected to due to the recitation of “the stream of sorted MSW comprises an average particle size between … 120 mesh”. It is noted that a particle’s size is a property of the particle, and it is not a physical material that can be comprised in the MSW. The phrase should be corrected to “the stream of sorted MSW comprises particles having a size between … 120 mesh”. Appropriate correction is required. This objection is maintained.
Claim Rejections - 35 USC § 112(b), or 112, Second Paragraph
Claims 1-7, 12-17, and 20-24 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention.
Claim 1 is indefinite due to the recitation of the content of the adjusted reformer feed gas generated in the step D). Specifically, the claim defines the content as: “a carbon dioxide content at a level grater or equal to 15 vol% and lower or equal to 50 vol%”; and “a methane content at a level grater or equal to 40 vol% and lower or equal to 85 vol%”. As such, the adjusted reformer feed gas in Step D) can have: a carbon dioxide content at a level of 15 vol% and a methane content at a level of 85 vol%, which collectively comprise 100 vol% of the adjusted reformer feed gas, thus not containing any impurity gas. However, the claim 1 defines a purification step for removing impurity gas from the adjusted reformer feed gas. It is unclear how the purification step E) can be carried out when an adjusted reformer feed gas does not contain any impurity gas. Furthermore, the contents recited in the step D) are conflicted with the further limitation “a methane to carbon dioxide content ratio of at least 3:2 and at most 4:1” recited in the step D). For example, the combination of 85 vol% of methane and 15 vol% of carbon dioxide in the adjusted reformer feed gas would give a methane to carbon dioxide ratio of 5.7 : 1, which is out of the claimed range “at least 3:2 and at most 4:1”. It is unclear how the adjusted reformer feed gas can have a ratio in the claimed range while their CO2 and CH4 contents are respectively in the claimed ranges of 15 vol% - 50 vol% and 40 vol% - 85 vol%.
Claim 1 is also indefinite due to the recitation of “repeating the subjecting the treated reformer feed gas for a plurality of passes” in the step H). It is unclear how the step of repeating the subjecting the treated reformer feed gas is performed, and whether the “treated reformer feed gas” is referred to newly added treated reformer feed gas or to partially reacted treated reformer feed gas recovered/recycled from the previous methanol synthesis reaction in for the step G).
The remaining claims are rejected for depending from an indefinite claim.
Claim Rejections - 35 USC § 103
Claims 1-6, 12-17, and 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over Bradin et al. (US 2018/0135004, 2018, of record) in view of Mortensen et al. (WO 2020/254121. 2020, cited in IDS), Giwa et al. (Journal of Cleaner Production, 2019, 233:711-719, of record), de Mes et al. (Bio-methane & Bio-hydrogen, 2003, 58-95, of record), and Tonkovich et al. (CN 101528337, 2009, the machine-translated English version is of record), as evidenced by the printout of MPa to Bar conversion (retrieved from the website of UnitConverters.net on 9/20/2024, of record), the printout of Bar to Psi convention (retrieved from the website of UnitConverters.net on 9/20/2024, of record), and Wikipedia printout of pressure swing adsorption (retrieved from the Wikipedia website on 2/20/2024, of record).
Bradin et al. teach an anerobic digestion system comprising an anerobic digestor for producing a biogas mixture comprising methane and carbon dioxide, coupled with a syngas generator for converting the gas mixture to syngas containing a mixture of carbon monoxide and hydrogen, and a gas-to-liquid reactor for converting the syngas to products including methanol/alcohol (claims 1 and 9) (Note: these apparatuses respectively read on the “anerobic digestion apparatus”, “steam methane reformer”, and “methanol synthesis reactor” recited in the instant claim 1; and they constitute “a plurality of instruments” along with a reciprocating compressor described below, thus meeting the claimed requirements). Bradin et al. also teach a method of using the anerobic digestion system for producing biogas mixture from waste, then converting the biogas mixture to syngas and then converting to products including methanol, comprising steps: providing pretreated biomass waste sourced from unsorted municipal solid waste (MSW) [Note: this step inherently comprises receiving a stream of unsorted MSW at a first set of instruments and extracting the unsorted MSW, thereby producing the biomass waste (a sorted MSW) via the first set of instruments, further explanation is provided below], introducing a liquid slurry (solution) of the biomass waste, as a feedstock, into the anerobic digestor, and retaining the liquid slurry in the anerobic digestor for a period of time (epoch) for anaerobic digestion of the biomass waste [Note: the anerobic digestor reads on the “second set of instruments”], thereby producing the biogas mixture comprising methane and carbon dioxide; treating the biogas mixture comprising methane and carbon dioxide, by a conversion process performed in the syngas generator (steam methane reformer, SMR), thereby producing a syngas containing a mixture of carbon monoxide and hydrogen (i.e. a treated biogas mixture); and subjecting the syngas/treated biogas mixture to a conversion process in the gas-to-liquid reactor (methanol synthesis reactor), thereby producing a conversion product, specifically methanol (paras 0002, 0005-9, 0011, 0081-82, 0107-0119, 0045-46, 0051-0053, Claims 1, 8-9, and 12-14); wherein the syngas is treated in the gas-to-liquid reactor at a pressure of 5-10 MPa for methanol production (para 0119, line 6); wherein the method further comprises receiving from one or more sources a stream of unsorted MSW (at a first set of instruments), processing/extracting the unsorted MSW through sorting (via the first set of instruments), and producing a stream of sorted MSW containing biological/organic waste, before introducing the sorted MSW (biomass waste) into the anaerobic digester for anaerobic digestion (paras 0081-82 and 0003, 0040-41); wherein the biomass waste introduced to the anaerobic digester (in the liquid slurry/solution) comprises digestible biological solids, including waste of supermarkets, food waste, food-processing waste, animal by-products, yard waste including grass, shrub and tree trimming, and paper waste (paras 0040, 0081-82); and wherein the method further comprises removing carbon dioxide from the biogas produced by the anaerobic digestion in the anerobic digestor, by using instruments for pressure swing absorption (Claim 5) (this step is equivalent to the adjusting step D) via third set of instrument in the instant claim 1 ).
It is noted that the term “reformer feed gas” recited in Claim 1 stands for a gas to be fed to a reformer apparatus. The biogas mixture comprising methane and carbon dioxide, taught by Bradin et al., is a feed gas for the reformer apparatus/syngas generator, thus reading on the claimed term. It is also noted that the treatment of the syngas to a pressure of 5-10 MPa in the method of Bradin et al. inherently comprises subjecting the syngas to a compressor to a pressure of 5-10 MPa. Although Bradin et al. do not teach the compressor is a reciprocating compressor, the claimed reciprocating compressor is well known and commonly used in the art for compressing gas. Thus, it would be obvious to use the reciprocating compressor for compressing gases in the method suggested by the cited prior art. It is further noted that the pressure of 5-10 MPa in the methanol synthesis taught by Bradin et al. is equivalent to the pressure between 725 psi and 1450 psi, given 5-10 MPa is equivalent 50-100 bar and one bar is equivalent to 14.5 psi, as evidenced by the printout of MPa to Bar conversion (page 1) and the printout of Bar to Psi convention (pages 1-2). The pressure between 725 psi and 1450 psi taught by Bradin et al. overlaps with the claimed range between about 1000 psi and 3000 psi, thus rendering the claimed range to be obvious. See MPEP 2144.05 (I), which states “in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists.”
Bradin et al. do not teach introducing a purge gas or a portion of the purge gas from a methanol synthesis reactor into the solution/liquid slurry in the anaerobic digester, as required by the step C) of the claim 1.
Mortensen et al. teach a method for producing methanol from biogas comprising carbon dioxide/CO2 and methane/CH4, comprising steps: providing a reformer feed stream/biogas, carrying out steam methane reforming of the reformer feed stream in a reforming reactor and producing a synthesis gas (syngas) from the reactor, and providing the syngas to a methanol synthesis reactor and producing a product comprising methanol and an off-gas (i.e. purge gas) (page 2/para 3 – page 3/pare 2: steps a), c), c2) and d), page 6/para 2, Claims 1, 14, 19-20), wherein the method further comprises an adjustment step for adjusting the CO2 content in the biogas (reformer feed stream) by removing CO2, before conducting the steam methane reforming process, so as to facilitate downstream methanol production (page 19/para 2, page 9/paras 2 and 4, Claim 19). Mortensen et al. further teach recycling a part/portion of the off-gas/purge gas to fermentation plant (anaerobic fermentation reactor) of a biogas production facility for producing biogas/methane from CO2, and that hydrogen in the off-gas reacts with CO2 and enhances biogas production (the para spanning pages 9 and 10, Claim 20, page 1/lines 14-20); and Mortensen et al. teach that a biogas produced with recycling purge gas has a benefit with a higher CH4/CO2 ratio compared to biogas produced with no recycling of the purge gas (page 10, lines 2-4). Examiner notes that biogas with a higher CH4/CO2 ratio is preferable for enhancing downstream methanol production, as supported by Mortensen et al. (page 19/lines 7-10, page 9/lines 20-24, more explanation is provided below).
Giwa et al. investigated effect of syngas and simulated gas mixtures of H2 and CO on biogas/methane production and bio-methanation performance of anaerobic digestion (AD) of food waste (abstract). Giwa et al. applied real syngas (G62, 60 vol% H2, 20 vol% CO2) as well as different concentrations of mixtures of H2 and CO (G21, 20 vol% H2, 10 vol% CO2; G23, 20 vol% H2, 30 vol% CO2; and G61, 60 vol% H2, 10 vol% CO2) as simulated syngas mixtures for the investigation (page 712/col 2/last para – page 713/col 1/para 2, page 713/the para spanning both columns, Table 1, page 712/abbreviation table). Giwa et al. demonstrate that both real syngas and simulated syngas mixtures comprising different concentrations of H2 and CO and ratios of H2/CO, enhance methanation and methane production of the AD, with no toxicity to the AD (abstract, page 718/col 1/first full para), and specifically that the stimulated syngas mixtures (including G21 and G23) from the anerobic treatment of food waste generated more methane (75-80%) than the control (45%) (abstract/lines 8-9 from bottom), while the real syngas generated methane (100%) (abstract, line 11-12); and Giwa et al. teach that CO content in all the reactors (G21, G23, G61, and G63) was completely degraded, (abstract, lines 7-10).
Before the effective filing date of the claimed invention, it would have been obvious to modify the method of Bradin et al. by introducing a portion (section portion) of hydrogen-containing purge gas stream from the methanol synthesis reactor into the anaerobic digester for enhancing production of biogas/methane in the anaerobic digester, as taught by Mortensen et al. and Giwa et al. One of ordinary skill in the art would have been motivated to do so, because it is well known in the art to recycle a portion of a H2-containing purge gas from a methanol synthesis reactor to an anaerobic digestor for biogas/methane production, as supported by Mortensen et al. In addition, recycling the H2-containing purge gas into the anaerobic digestor has the advantage of producing a biogas having a higher CH4/CO2 ratio, which is preferable for enhancing downstream methanol production, as supported by Mortensen et al. Furthermore, hydrogen in the purge gas promotes biogas/methane production, as supported by Mortensen et al. and Giwa et al. One of ordinary skill in the art has a reasonable expectation of success at modifying the method of Bradin et al. based on the teachings of the cited prior art, because both the method of Mortensen et al. and the method of Bradin et al. are directed to using biogas for methanol production, and the teachings of Mortensen et al. about recycling purge gas for biogas production are readily applicable to the method of Bradin et al. Furthermore, the method of Bradin et al. comprises a process of anaerobic digestion of waste material (food waste) for producing a biogas containing methane. As such, the teachings of Mortensen et al. and Giwa et al. about introducing H2-containing gases into anaerobic digestion process for enhancing biogas/methane production are readily applicable to the method of Bradin et al.
Regarding the limitation “the purge gas comprises a hydrogen content at a level less than 20 vol%” recited in the step C) of claim 1, Giwa et al. further teach that each of the gas mixtures composed of H2 and CO (including G21 and G23 having 20 vol% H2) was flushed into each anaerobic bottle/reactor only for 10 min, and the reactors were fed only once (page 713/left col/para 2: lines 4-7). These teachings indicate that before bio-methanation starts the reactors flushed with G21 and G23 have the highest H2 concentration of 20 vol%, However, as soon as the H2 starts to react and degrades for providing energy for biogas methane production, H2 concentrations in the reactors drop to a level less than 20 vol% (given no additional H2 was fed to or flushed into the reactors to maintain its level to be consistent). As such, H2 at a level of less than 20 vol% is involved for promoting methane production in the AD of Giwa et al. Furthermore, Giwa et al. teach that during the trial period, the H2 was completely degraded in all the reactors (G21, G23, G61, and G63) (page 714/right col/lines 2-4, Fig. 3.), which further supports that the hydrogen level in G21 and G23 continued to drop to a level below 20 vol% during the AD for providing energy, until its level dropped to 0%, while such a H2 at a level of <20 vol% continued to contribute to methane production. Thus, in view of the teachings of Giwa et al. about effectiveness of H2 at a level of <20 vol%, it would have been obvious to recycle a purge gas containing H2 at a level of <20 vol% for anerobic digestion in the method of Bradin et al. for enhancing production of biogas/methane.
Regarding the limitation about the contents of the reformer feed gas recited in step C) of Claim 1, Bradin et al. further teach the biogas produced from the digestor typically contains approximately 65% CH4, 34% CO2 (para 0042). Bradin et al. do not specifically indicate these gas percentages as volume percentages. However, de Mes et al. teach volume percentages of biogas produced from anaerobic digestion of waste material by disclosing that the biogas is a mixture of CH4 between 55-75 vol% and CO2 between 25-45 vol% (title, abstract/lines 1-3) (note: these ranges encompass the specific ranges taught by Bradin et al.), which either overlap or read on the claimed ranges (20-69 vol% and 10-60 vol%) for CH4 and CO2, thus meeting the limitations about CH4 and CO2. Regarding the limitation of the impurity (at >20 vol%) in step C), Bradin et al. teach the biogas comprises impurity such as sulfur (H2S) (para 0042). rendering the reformer feed gas produced in the step C) to be obvious. Given the cited prior art teaches CH4 between 55-75 vol% and CO2 between 25-45 vol%, the biogas may comprise 20 vol% of impurity when its CH4 and CO2 are respectively at levels of 55 vol% and 25 vol% (100% – 80% = 20%). The 20 vol% of impurity nearly touches the claimed >20 vol%, thus rendering the claimed range to be obvious. Regarding the claimed CH4 to CO2 ratio of less than 3:1 in step C), 55% CH4 and 25% CO2 indicated above have a ratio of less than 3:1, thus meeting the limitation about the claimed ratio.
Regarding the adjusting step D) recited in Claim 1, Bradin et al. and Mortensen et al. teach an adjusting step for producing an adjusted biogas by removing CO2 from biogas through a separation process, as indicated above. Regarding the contents of CO2 and CH4 of the adjusted reformer feed gas recited in the step D) of claim 1, Bradin et al. further teach that the production of synthesis gas from methane produces 3 moles of hydrogen gas for every mole of carbon monoxide (CO2+H2O [Wingdings font/0xE0] CO+ 3H2), while the methanol synthesis consumes only 2 moles of hydrogen gas per mole of carbon monoxide (CO + 2H2 [Wingdings font/0xE0] CH3OH), thus leaving one mole of excess hydrogen (para 0119/last line, para 0120/lines 1-6, para 0108/last line), indicating an ideal ratio of H2/CO being 2:1; and Bradin et al. further teach using CO2 reformer (CH4 + CO2 [Wingdings font/0xE0] 2CO + 2H2) to balance the H2:CO ratio and to obtain an ideal ratio of H2/CO by adjusting the amount of steam methane reforming and CO2 reforming (paras 0110 and 0111). The combination of steam methane reforming and CO2 reforming processes for balancing H2:CO ratio would arrive at a chemical equation 3CH4 + CO2 + 2H2O[Wingdings font/0xE0] 4CO + 8H2, from which an ideal H2/CO ratio of 2:1 can be obtained for methanol production from a reaction between 3 moles of methane gas and one mole of CO2 gas (a CH4/CO2 ratio of 3:1, e.g. 75% CH4 reacts with 25% of CO2 in the absence of impurity). Mortensen et al. teach a chemical equation, consistent with teachings of Bradin et al.,
0.75CH4 + 0.25CO2 + 0.5H2O[Wingdings font/0xE0] CO + 2H2 [Wingdings font/0xE0] CH3OH, for achieving an advantageous methanol production (page 19/last line, page 9/lines 20-24), in which 0.75CH4 (e.g. 75 vol% CH4) reacts with 0.25CO2 (e.g. 75 vol% CH4) to produce 2H2 and CO (with an ideal ratio of 2:1) for producing one mole of CH3OH without any excess H2 molecules left in the reactions. Mortensen et al. indicate when biogas/reformer feed stream has more than 25% CO2, it is advantageous to remove some CO2 to reach an adjusted biogas/reformer feed stream with about 25% CO2 and about 75% CH4, which is preferable for downstream methanol production (page 9/lines 21-24, page 19/lines 7-10). As such, an adjusted biogas having a CO2 content of about 25 vol% and a methane content of about 75 vol% would have been obvious in view of the teachings of Bradin et al. and Mortensen et al., which read on the claimed CO2 (15-50%) and methane (40-85%) contents in the step D) of claim 1. Regarding the newly recited limitation about the CH4 to CO2 ratio in step D), the combined teachings of the cited prior art suggest a CH4/CO2 ratio of 3:1 (as indicated above), which reads on the claimed ratio between 3:2 and 4:1, thus meeting the claimed limitation. Examiner also notes that the step of adjusting biogas in the method suggested by the cited prior art inherently comprises applying an additional set of instruments for adjusting the biogas, thus meeting the limitation requirement about the “third set of instruments” recited in the step D).
Regarding the purification process recited in the step E), Bradin et al. teach removing a gas of sulfur compound, H2S from the biogas/reformer feed gas, typically by a scrabbing process (para 0042); and Mortensen et al., who teach subjecting reformer feed gas/biogas to a desulfurization unit/purification unit 30 (reading on the claimed “purification apparatus”) for desulfurizing the reformer feed gas/biogas by removing sulfur or one or more sulfur compounds, after adjusting CO2 content by separating CO2 from the biogas in a separation unit upstream of a preheating unit 20 and the purification unit 30 (page 17/lines 16-18 and 23-25, page 19/para 2, Fig. 1). These teachings supports that it is a common procedure in the art to remove toxic gases such as sulfur or one or more sulfur compounds from reformer feed gas sent to methane reformer. Regarding the limitation about the specific contents of the purified reformer feed gas recited in step E), Bradin et al. do not teach a specific gas content of the purified biogas. However, Bradin et al. teach H2S is at a level of 0.5% in the biogas (para 0042). As such, after removing the impurity of sulfur the contents of CH4 and CO2 would still be still close to 75 vol% and 25 vol%, respectively. In addition, Mortensen et al. (the top table of Example 1, page 25) shows the results of steam methane reforming, including the gas contents in an “Inlet reformer” “8” (i.e. reformer feed gas sent to a steam methane reformer/eSMR, which is considered as the reformer feed gas obtained after adjusting and purifying steps), wherein the Inlet reformer feed gas has: CH4 at a level of 1997 Nm3/h, CO at 1 Nm3/h, CO2 at 617 Nm3/h, H2 at 93 Nm3/h, and N2 at 18 Nm3/h, which can be converted respectively to volume percentages: CH4 with a content of about 74 vol%; and CO2 with a content of about 22 vol%. Overall, the contents of CH4 and CO2 taught by Mortensen et al. and Bradin et al. either nearly touch or read on the claimed ranges 75-80 vol% (for CH4) and 20-23 vol% (for CO2), which render the claimed ranges to be obvious.
Regarding the limitation about the specific contents of the treated reformer feed gas recited in step F), Mortensen et al. (the top table of Example 1, page 25) shows the results of steam methane reforming (for generating the treated reformer feed gas), including: gas contents in an “Inlet reformer” “8” (i.e. reformer feed gas sent to a steam methane reformer/eSMR) and gas contents of “Outlet reformer” (i.e. syngas or treated biogas/reformer feed gas, produced by steam methane reforming), wherein the treated biogas/reformer feed gas has: CH4 at a level of 113 Nm3/h, CO at 2208 Nm3/h, CO2 at 294 Nm3/h, H2 at 5421 Nm3/h, and N2 at 18 Nm3/h, which can be converted respectively to volume percentages: H2 with a content of about 67 vol%, CO with a content of about 27 vol%, CO2 with a content of about 4 vol%, and an impurity (CH4 and N2) with a content of about 2 vol%, which respectively read on the claimed ranges for H2 (60-78%), CO (14-33%), and impurity (less than 6 %) recited in the step F), except the claimed range for CO2 (5-20 vol%). However, the CO2 content of about 4 vol% is close to the low end of the claimed range 5-20 vol%, thus, rendering the claimed CO2 range to be obvious in absence evidence of criticality.
Regarding the step G) in the claim 1, the recited prior art suggests a step of subjecting the treated reformer gas to a reciprocating compressor at a pressure from 1000 PSI to 3000 PSI to form a compressed treated reformer feed gas for methanol synthesis and producing methanol in the methanol synthesis reactor, as indicated above. Regarding the claimed conversion efficiency for the conversion to methanol, Bradin et al. and Mortensen et al. are silent about specific conversion efficiency. However, the claimed conversion efficiency is directed to the outcome of the claimed method for the methanol synthesis. The cited prior art suggests a method comprising all the step limitations same as those recited in the claim 1. In the absence of evidence to the contrary, it is presumed that a method having substantially the same steps is capable of generating substantially the same outcome (i.e. the same conversion efficiency). Thus, the step G) would have been obvious over the cited prior art.
Regarding the step H) in the claim 1, Mortensen et al. teach repeatedly sending the treated reformer feed gas into methanol synthesis reactor for producing methanol, specifically, recycling and collecting off-gasses, i.e. partially reacted treated reformer feed gas, from the previous methanol synthesis step (equivalent to the step G) of claim 1), and mixing the off-gasses with make-up synthesis gas compressed by pressure, and then sending the mixed gases to the methanol synthesis reactor for producing methanol; and a last fraction of off-gasses is exported as a fuel-rich off-gas (i.e. purge gas) (page 24/lines 23-29 and page 25/lines 1-2, Fig. 1). Regarding the limitation “a plurality of passes” in the step H), Mortensen et al. teach repeatedly passing the treated reformer feed gas to the methanol synthesis reactor, such that the un-reacted treated reformer feed gas from the previous methanol synthesis reaction can be re-utilized for producing methanol. A specific number of passes in the method suggested by the cited prior art can be modified through routine optimization based on specific H2 and CO contents in the off-gasses (partially reacted treated reformer feed gas) for enhancing the utilization efficiency of the off-gases.
Regarding the carbon efficiency recited in the step H), a 95% efficiency would have been obvious over the prior art. In support, Mortensen et al. teach a carbon efficiency of 95.4% (page 25, lines 3-4). Further in supported, Tonkovich et al., teach a method for formation of methanol, comprising: reacting a portion of carbon-containing molecules (CO and CO2) with hydrogen-containing molecules (H2) to generate methanol; removing the methanol from the process stream; and reacting a further portion of carbon-containing molecules with hydrogen-containing molecules, wherein greater than ninety percent (> 90%) of the carbon containing molecules are reacted to form methanol (i.e. the carbon efficiency is more than 90%) (Claims 1, 58, 60-61 in pages 26 and 32, paras 0005, 0017 and 0067), wherein the carbon-containing and hydrogen-containing molecules are syngas that comprises carbon dioxide, carbon monoxide and hydrogen (para 0067, Claims 58 and 60-61). Given the >90% carbon efficiency encompasses the claimed 95% carbon efficiency, the teachings of Tonkovich et al. render the claimed carbon efficiency to be obvious. See MPEP 2144.05 (I). Regarding the specific amounts of methanol produced per day recited in the step H), the cited prior art does not expressively teach producing methanol from 18,144 kg to 226, 896 kg per day. However, a total amount of methanol produced each day is an obvious design choice in the method suggested by Bradin et al., de Mes et al., and other cited prior art, which is readily increased based on factors such as an increased demand for methanol production, and an increased amount of available biogas, reform feed gas or syngas produced from upstream processes. Therefore, the teachings of the cited prior art render the step H) to be obvious.
Regarding additional limitations in the steps A) and B) of Claim 1, Bradin et al. teach obtaining from one or more sources a stream of unsorted MSW, processing the unsorted MSW through sorting, and producing a stream of sorted MSW containing biologically digestible organic waste before introducing the stream of sorted MSW into the anaerobic digester, as indicated above. Bradin et al. further teach the stream of sorted MSW has a concentration of approximately 9% total solids (para 0041, lines 3-5), and specifically 8-10% by weight solids (para 0046, lines 2-3 from bottom), which reads on the claimed range between 5 wt% and 10 wt% solid concentration, recited in the step B). Thus, the teachings meet the requirement of steps A) and B).
Regarding the limitation “a portion of the stream of sorted MSW” recited in step C) of Claim 1, Bradin et al. does not specifically teach introducing a portion of the stream of sorted MSW into the anaerobic digester. Bradin et al. (para 0041) conducted a single batch of anaerobic digestion, in which the anaerobic digester is introduced with the entire stream of sorted MSW. However, how many amounts of the stream of sorted MSW is introduced into an anaerobic digester is deemed merely a matter of design choice and judicious selection, which is well within the purview of the skilled artisan having the cited reference before him/her as a guide. For example, a large scale of MSW sorting for providing hundreds of thousands of tons of sorted MSW for anaerobic digestion has been well established in the art, as supported by de Mes et al., who teach a method for anerobic digestion of sorted organic waste fraction of MSW for producing biogas, comprising subjecting the organic waste fraction to anerobic digestion in a liquid slurry (abstract, Figs 1-2, page 59/section 4.2.1, pages 62-65/section 4.3.1.1); and further teach that the processing capability of biodegradable waste (sorted MSW, organic waste fraction) in anaerobic digestion plants is ranged up to 190000 tonnes/year (t.p.a.) (page 62/left col/para 4, Appendix I) . As such, it would be an obvious design choice to introduce such a large stream of sorted MSW of biodegradable waste into parallel anaerobic digestors for a large scale of anaerobic digestion process for biogas production (Note: it is a common practice in the art to use parallel reactors, as evidenced by Mortensen et al., page 5/line 13), such that a portion of the stream of sorted MSW is introduced into an anaerobic digestor, and subsequent portions of the stream of sorted MSW are respectively into the remaining reactors.
Regarding the limitation “… (MSW) at a level of greater than 900,000 kg and less than 13.6 million kg per day” newly recited in the step B) of claim 1 as well as the further limitation recited in claim 6, de Mes et al. teach total biogas production capacity increases worldwide over years. It is noted that the process of Bradin et al. is readily scaled up for producing more biogas in a large scale. de Mes et al. (Appendix I) provides the processing capability of biodegradable waste (organic waste fraction) in anaerobic digestion plants, which is ranged up to 190000 tonnes/year (t.p.a.), which can be converted to 1.9 x 108 kg/year, or 5.2 x 105 kg/day (1 tonne = 1000 kgs). If assuming half of unsorted MSW is sorted/separated into the biodegradable organic waste fraction used in the anaerobic digestion of the plants, a stream of the unsorted MSW would be at an amount up to 380000 tonnes/year, i.e. up to 1.04 x106 kg/day, which overlaps with the claimed ranges, thus rendering the claimed ranges to be obvious.
Regarding Claim 12, Bradin et al. are silent about details about converting biogas to syngas and then to methanol. However, it is a common practice in the art to apply the processes specifically recited in the claim 12 for carrying out methane reforming and processing reformed biogas/reformer feed gas (syngas) to be sent to a methanol synthesis reactor for downstream methanol production, as supported by Mortensen et al., who teach: cooling and separating water from synthesis gas/syngas in a separator to get dry syngas (reading on a chilling and a dehydration processes), and compressing the dehydrated/dry syngas in a compressor to get a compressed syngas (reading on a gas-compression process), before sending the treated syngas to a methanol synthesis reactor (page 24/lines 20-26, page 18/lines 4-8). Given Bradin et al. and Mortensen et al. use substantially same methods for converting biogas to syngas and then to methanol, it would have been obvious to adopt the teachings of Mortensen et al. into the method of Bradin et al. by including the dehydration, chilling, and compressing processes for effectively treating syngas (treated reformer feed gas) for methanol production.
Regarding Claim 21, Bradin et al. is silent about a total volume of the liquid slurry (solution). However, a total volume of the liquid slurry in the anaerobic digester is an obvious design choice in the method suggested by Bradin et al., de Mes et al., and other cited prior art, which is readily adjustable based on factors such as a total amount of biogas demanded to produce, capacity of anaerobic digesters, and a total amount of sorted biological/organic waste portion subjected to anaerobic digestion. In addition, de Mes et al. teach, as an example, the total digester capacity of biogas plants in Denmark, which is ranged up to 8500 m3 (Table 7), which is readily applicable to the method suggested by Bradin et al., de Mes et al., and other cited prior art. Although the 8500 m3 capacity of de Mes et al. does not match the volumes recited in the claim, it is noted that differences in volumes/dimensions, when the volumes/dimensions do not affect performance/operation, are prima facie obvious. MPEP 2144.04(IV)(A). Furthermore, de Mes et al. teach total biogas production capacity increases worldwide over years. With such yearly increased biogas production capacity, adjustment of a particular volume of the slurry liquid to arrive the claimed total volume range is deemed merely a matter of design choice, judicious selection, and routine optimization which is well within the purview of the skilled artisan having the cited reference before him/her as a guide.
Regarding Claim 22, Bradin et al. teach separating/removing a part of CO2 by using a pressure swing absorption apparatus (PSA) or a membrane system (note: involved with a filtration process) (Claim 5, para 0010). As evidenced by the printout of Wikipedia, the using a pressure swing absorption apparatus comprises an adsorption processes, including gas compression under pressure, and absorbing target gas to fixed-bed with medium/elective adsorbent materials (see page 1, 1st para). Thus, the teachings of Bradin et al. meet the requirement of the claim.
Regarding Claim 2, Bradin et al. teach the unsorted MSW comprises a food waste, a garden waste, a wood waste, a crop waste, a food manufacture byproduct, an animal waste/by-product, a fat, oil, and/or grease waste, a sewage sludge, or a combination thereof (paras 0082 and 0003).
Regarding Claim 3, this claim defines a content (~10 to ~30 wt%) of wood waste in unsorted MSW. However, the claim does not specifically define how the wood waste to be sorted or processed, rather the claim only broadly requires a step A) of obtaining from one or more resources a stream of unsorted MSW containing such a wood waste. It is note that depending upon resources a specific wood waste content in a stream of unsorted MSW is a variable, which includes the claimed range of ~10 to ~30 wt%. For example, Bradin et al. teach that unsorted MSW typically comprises around 60-80 wt% of organic fraction consisting of lignocellulosic waste and food waste, wherein the lignocellulosic waste includes paper products and yard/garden waste (para 0082/lines 4-7), and the yard/garden waste (“green” waste) includes tree trimmings and shrub (i.e. wood waste) (para 0003, lines 9-11). If assuming the unsorted MSW is obtained from a food-waste dominant resource and half of the organic fraction is food waste, the unsorted MSW would comprise 30-40 wt% of lignocellulosic waste; and If assuming half of the lignocellulosic waste is wood waste, a wood content would be 15-20 wt%, reading on the claimed range, thus meeting the requirement of obtaining a stream of unsorted MSW having a wood waste content of ~10 to ~30 wt%. It is also noted that the techniques for sorting lignocellulosic waste including various contents of wood waste and converting it to biogas or syngas have been well established in the art, as supported by de Mes et al., who teaches the capability of processing biodegradable waste from MSW in anaerobic digestion plants, reaches up to 190000 tonnes/year, and as evidenced by Giwa et al., who teach difficult-biodegradable waste (DBF) containing wood waste material such as lignin and fibers (lignocellulosic fibers), sorted from waste facility center, can be effectively converted to a H2-rich syngas through pyrolysis and direct gas-to-liquid (water) processes (page 712/col 2/paras 2-3, page 713/col 1/paras 3-4, page 718/col 1/1st full para); and as evidenced by Bradin et al. described above and in paras 0083-0095. It should be noted that "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation” (see MPEP 2144.05, (Il)-A). In the absence of evidence of criticality, Examiner takes the position that the claimed range about wood waste in a stream of unsorted MSW would be obvious over the combined teachings of the cited prior art.
Regarding Claim 4, de Mes et al. further teach that the organic fraction of MSW has a biogas yield of 80-200 m3 per tonne, and a total production capacity will increase worldwide over years (abstract/lines 10-11 and last 5 lines). In addition, de Mes et al. provide the processing capability of biodegradable waste of anaerobic digestion plants, which is ranged up to 190000 tonnes/year (see Appendix I), which gives a biogas flow rate in range up to 1.52 x107- 3.8 x107 m3 per year, or 4.16 x104- 1.04 x105 m3 per day, or about 1735 – 4335 m3 per hour (based on the biogas yield of 80-200 m3 per tonne, taught by de Mes et al.), which does not exactly match the claimed mass flow rate range. However, de Mes et al. teach total biogas production capacity increases worldwide over years. With increased biogas production capacity, the adjustment of particular conventional working conditions to arrive the claimed mass flow rate is deemed merely a matter of design choice, judicious selection, and routine optimization which is well within the purview of the skilled artisan having the cited reference before him/her as a guide. Thus, Examiner takes the position that the mass flow rate recited in claim 4 would be obvious over the teachings of the cited prior art.
Regarding Claim 5, the organic waste fraction and/or animal manure taught by de Mes et al. (abstract, page 63/col 2: para 1/line 9, last para/lines 1-2) are 100% biological waste. The sorted MSW used for anaerobic digestion, taught by Bradin et al., is also 100% biological waste, which includes a food waste, a garden waste, a wood waste, a crop waste, a food manufacture byproduct, an animal waste, as indicated above. It would have been obvious to prepare a steam of sorted MSW with only biological waste and introduce it (a first portion) into the anaerobic digester in the method suggested by Bradin et al. and other cited prior art for producing biogas, because removing un-fermentable/nondigestible MSW and adding only biological waste to the anaerobic digester will allow the anaerobic digester to have more space to hold more biologically digestible waste, thus increasing efficiency of anaerobic digestion and biogas production.
Regarding Claim 13, this claim recites limitations only to define the anaerobic digester used in the claimed method, but not the steps in the method. The recited limitation “configured to continuously … agitate the solution” is directed to the function of the anaerobic digester. The anaerobic digester of Bradin et al. (claim 4) comprises a cavitation stirrer configured to stirs continuously or intermittently the slurry. de Mes et al. also teach the anaerobic digester/reactor comprises a stirrer (page 63/Fig. 3), which is configured to stirs continuously or intermittently the slurry.
Regarding Claims 14 and 15, Bradin et al. are silent about specific temperature and time ranges of the anaerobic digestion. Giwa et al. further teach the anaerobic digestion treatment of food waste at a temperature of 35oC (i.e. 95oF) and for 600 hours (i.e. 25 days) (page 713/col 1/para 2/lines 8-9, and page 714/col 2/line 2, Figs. 3-5 and 7), which read respectively on the claimed temperature and time ranges. de Mes et al. further teach that methane production from anaerobic digestion increases with increasing temperature and reaches a maximum level at 35 to 37°C (reading on the claimed range 85oF -105oF) (page 60/left col/para 3/lines 8-10 from bottom); and that the retention time in the anaerobic digester/reactor is typically in the range of 2-4 weeks (14-28 days) (page 62/col 2: last para/last 5 lines), specifically 10, 18 or 20 days (page 64, col 2: paras 3-4), which read on the claimed time range. In view of the fact that the claimed temperature and time ranges have been commonly and effectively used in the prior art for anaerobic digestion treatment of waste material for biogas production, it would have been obvious to one of ordinary skill in the art to perform the anaerobic digestion for a time period from about 5 days to about 55 days and at a temperature from 85oF to 105oF in the method of Bradin et al. for efficiently producing the biogas comprising methane and CO2.
Regarding Claim 16, Bradin et al. are silent about specific temperature range of the anaerobic digestion. However, de Mes et al. further teach that when thermophilic bacteria are involved in the anaerobic digestion, a maximum methanogenic activity for methane production occurs at about 55°C (i.e. about 131 oF) (page 60/left col/para 3, last 8 lines). In view of the cited prior art, it would have been obvious to incorporate the temperature range of de Mes et al. to the method of Bradin et al. for reaching the maximum methane/biogas production involved with anaerobic digestion by thermophilic bacteria. Examiner notes that the temperature range about 131 oF taught by de Mes et al. renders the claimed range 115 oF - 130 oF to be obvious. This is because the modifier “about” used by de Mes et al. indicates that a precise temperature is not required for the anaerobic digestion. One of ordinary skill in the art would have understood that any temperatures close to 131 oF, such as 129 oF and 130 oF (within the claimed temperature range) would reasonably be expected to be effective.
Regarding Claim 17, Bradin et al. teach that the liquid slurry (solution) comprises approximately 9% (para 0041/lines 3-5), or 8-10% (para 0046, last 3 lines) of digestible biological solid by weight, which reads on the claimed range of about 5% to about 25%.
Therefore, the invention as a whole would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention.
Claims 1-6, 12-17, and 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over Bradin et al. (US 2018/0135004, 2018, of record) in view of Mortensen et al. (WO 2020/254121. 2020, cited in IDS), Giwa et al. (Journal of Cleaner Production, 2019, 233:711-719, of record), Tonkovich et al. (CN 101528337, 2009, the machine-translated English version is of record), and de Mes et al. (Bio-methane & Bio-hydrogen, 2003, 58-95, of record), as applied to Claims 1-6, 12-17, and 21-22, further in view of Nieminen et al. (Processes 2019, 7(405):1-24, of record) and Paulo et al. (Water Sci Technol, 2001, 44 (4): 129–136, abstract, of record), as evidenced by the printout of MPa to Bar conversion (retrieved on 9/20/2024 from UnitConverters.net, of record), the printout of Bar to Psi convention (retrieved on 9/20/2024 from UnitConverters.net, of record), and Wikipedia printout of pressure swing adsorption (retrieved from the Wikipedia website on 2/20/2024, of record).
The teachings of Bradin et al., de Mes et al., Mortensen et al., Tonkovich et al. and Giwa et al. are described above.
Regarding Claim 20, Bradin et al. do not teach introducing wastewater from a methanol purification apparatus into the solution/liquid slurry in the anaerobic digester.
However, Bradin et al. further teach synthesizing methanol from the syngas having hydrogen and CO through a reaction between 2 H2 and CO, producing a methanol molecule, and a reaction between CO2 and 3 H2, producing a methanol molecule and a water molecule, (see chemical equations in paras 0119 and 0120), indicating water is a by-product; and Bradin et al. indicate that procedures for synthesizing/purifying methanol are well known in the art (para 0119).
Nieminen et al. teach a process of methanol synthesis by following the chemical equation taught by para 0120 of Bradin et al., wherein a gas feed containing molar ratio of three moles H2 per mole CO2 is used for the methanol synthesis (page 7, past para/lines 4-5 from bottom), and a liquid product stream consisting of methanol and water in a molar ratio of one to one is fed to a distillation column (DIST1) for purification of methanol, wherein the methanol is released from the top of the column and has a final purity of 99.3 wt%, and the water/wastewater with a purity 99.0%wt is removed from the bottom of the DIST1 column through a wastewater outlet (“31”) (Fig. 2, page 8/para 2). It is noted that the distillation column used for separating methanol from water can be considered as a methanol purification apparatus of the plurality of instruments.
Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to modify the method of Bradin et al. by introducing wastewater from the methanol synthesis process to the liquid slurry in the anaerobic digestor in the method suggested by Bradin et al. and other cited prior art for making the biogas production to be cost-effective and enhancing biogas production, wherein the wastewater is recovered from a methanol purification apparatus, because it had been well known in the art that water is a by-product of methanol synthesis, as supported by Bradin et al. and Nieminen et al.; and water/wastewater with a good purity (99.0%wt) is readily separated and recovered from distillation column (i.e. a methanol purification apparatus) during the process of purifying methanol for methanol production, as supported by Nieminen et al. Recycling such water into the anaerobic digestion process in the method suggested by Bradin et al. would reduce amounts of fresh water used in the process, thus saving the cost of water and making the process cost-effective and environmentally friendly. Furthermore, it has been well known in the art that methanol in wastewater is anaerobically digestible by microbial digestion in an anaerobic digester, as supported by Paulo et al., who teach treatment of methanol-containing wastewater by thermophilic anaerobic digestion, and demonstrate a good performance that methanol in wastewater is effectively degraded by microorganisms in the anaerobic digestor (see tile and abstract). As such, any methanol remained in the wastewater obtained from methanol purification in the method suggested by Bradin et al. is readily digestible by microorganisms of anaerobic digestion, thus enhancing biogas production in the anaerobic digester of Bradin et al.
Therefore, the invention as a whole would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention.
Claims 1-6, 12-17, 21-22 and 24 are rejected under 35 U.S.C. 103 as being unpatentable over Bradin et al. (US 2018/0135004, 2018, of record) in view of Mortensen et al. (WO 2020/254121. 2020, cited in IDS), Giwa et al. (Journal of Cleaner Production, 2019, 233:711-719, of record), Tonkovich et al. (CN 101528337, 2009, the machine-translated English version is of record), and de Mes et al. (Bio-methane & Bio-hydrogen, 2003, 58-95, of record), as applied to Claims 1-6, 12-17, and 21-22, further in view of Topf et al. (US 2007/0129449, 2007, of record), as evidenced by the printout of MPa to Bar conversion (retrieved on 9/20/2024 from UnitConverters.net, of record), the printout of Bar to Psi convention (retrieved on 9/20/2024, from UnitConverters.net, of record), and Wikipedia printout of pressure swing adsorption (retrieved from the Wikipedia website on 2/20/2024, of record).
The teachings of Bradin et al., de Mes et al., Mortensen et al., Tonkovich et al. and Giwa et al. are described above.
Regarding Claim 24, Bradin et al. and cited prior art do not teach introducing purge gas at a mass flow rate between 1000 kg/h and 2000 kg/h. However, it had been well known in the art to produce a purge gas from a methanol synthesis process at a mass flow rate at an amount falling into the claimed range, and such an amount can provide the advantage of effectively avoiding accumulation of the inert gas constituents in the methanol synthesis reactor, thus facilitating methanol production, as supported by Topf et al. teach a method of producing methanol as a liquid energy carrier (para 0001), comprising: introducing synthesis gas (syngas) comprising hydrogen and carbon monoxide into a synthesis apparatus for producing methanol, wherein a purge gas “P” in an amount of 1276 kg/h is removed from the apparatus in order to avoid accumulation of the inert gas constituents (paras. 0049-50, 0074, page 3/col 2/lines 1-3) (it is noted that the amount of 1276 kg/h reads on the claimed range of 1000 kg/h – 2000 kg/h). As such, it would have been obvious to one of ordinary skill in the art to conduct the methanol synthesis by removing a purge gas in a range of 1000 kg/h – 2000 kg/h from the methanol synthesis reactor in the method suggested by Bradin et al. and other cited prior art for facilitating methanol production and introducing the purge gas to the anaerobic digestion for improving biogas production.
It is noted that an obvious design choice to set up a specific flow rate for introducing purge gas into the anaerobic digester in the method suggested by Bradin et al. and other cited prior art, which is readily adjustable based on factors such as a total amount of biogas demanded to produce, capacity of anaerobic digesters, and a total amount of sorted biological/organic waste portion subjected to anaerobic digestion.
de Mes et al. teach total biogas production capacity increases over years. Topf et al. further teach that methanol is an alternative fuel for the traffic sector and offers the advantage of a considerable replacement potential for the fuels required today because renewable resources will play an important role in the longer term (para 0004, lines 4-8). With increased biogas production capacity and advantage of providing methanol as an alternative renewable liquid fuel, the adjustment of particular conventional working conditions in the biogas and methanol/purge gas productions to arrive a large production scale with the claimed mass flow rate is deemed merely a matter of design choice, judicious selection, and routine optimization which is well within the purview of the skilled artisan. Thus, Examiner takes the position that the mass flow rate recited in claim 4 would be obvious over the teachings of the cited prior art, in the absence of evidence of criticality.
Therefore, the invention as a whole would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention.
Claims 1-6, 12-17, and 21-23 are rejected under 35 U.S.C. 103 as being unpatentable over Bradin et al. (US 2018/0135004, 2018, of record) in view of Mortensen et al. (WO 2020/254121. 2020, cited in IDS), Giwa et al. (Journal of Cleaner Production, 2019, 233:711-719, of record), Tonkovich et al. (CN 101528337, 2009, the machine-translated English version is of record), and de Mes et al. (Bio-methane & Bio-hydrogen, 2003, 58-95, of record), as applied to Claims 1-6, 12-17, and 21-22, further in view of Vikhareva et al. (Sustainability 2022, 14, 9278, pages 1-16, publication date: 7/28/2022, of record), as evidenced by the printout of MPa to Bar conversion (retrieved on 9/20/2024 from UnitConverters.net, of record), the printout of Bar to Psi convention (retrieved on 9/20/2024, from UnitConverters.net, of record), and Wikipedia printout of pressure swing adsorption (retrieved from the Wikipedia website on 2/20/2024, of record).
The teachings of Bradin et al., de Mes et al., Mortensen et al., Tonkovich et al. and Giwa et al. are described above.
Regarding Claim 23, Bradin et al. and cited prior art do not teach a particle having a size of 50-120 mesh. However, Bradin et al. teach that the stream of sorted MSW are solid particles with maximum particle size of 6-7 mm wide by 10-15 mm length (para 0046, last 2 lines), the scope of which encompasses the claimed size range of 50 mesh -120 mesh (Note: 50 mesh -120 mesh is equivalent to 0.125 mm – 0.297 mm).
Vikhareva et al. teach that anaerobic digestion is a biological process in which organic matter is decomposed under anaerobic conditions into simple compounds, and one of the products is methane, an environmentally friendly renewable energy source (page 1, para 2, lines 1-3). Vikhareva et al. indicate that a particle size of organic matter influences the process of methanogenesis of anaerobic digestion, and specifically, large particles lead to clogging of the reactor, while small particles provide a large surface area for adsorption, which leads to an increase in microbial activity and an increase in biogas output (page 4, para 5, lines 1-3). Vikhareva et al. further teach that the effect of different particle sizes on the amount of biogas produced was studied for sizes of 0.088, 0.40, 1.0. 6.0, and 30.0 mm. It was found that the maximum amount of biogas was produced from raw materials with a particle size of 0.088 and 0.40 mm (page 4, para 5, lines 3-6).
It would have been obvious to reduce sizes of solid particles in the stream of sorted MSW in the method suggested by Bradin et al. and other cited prior art for providing a stream of sorted MSW having solid particles with sizes in the range of 50 mesh -120 mesh to the anaerobic digester, thus enhancing biogas production, because it had been well known in the art that small particles provide a large surface area for adsorption, which leads to an increase in microbial activity and an increase in biogas output, as supported by Vikhareva et al. Furthermore, Vikhareva et al. teach a specific particle size range of 0.088 - 0.40 mm, which produces the maximum amount of biogas from anaerobic digestion. It is noted that the range of 0.088 - 0.40 mm taught by Vikhareva et al. is sufficiently narrow and specific, which renders the claimed range of 50 mesh -120 mesh (equivalent to 0.125 mm – 0.297 mm) to be obvious. See MPEP 2144.05 (I), which states “in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists.”
Therefore, the invention as a whole would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention.
Claims 1-7, 12-17, and 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over Bradin et al. (US 2018/0135004, 2018, of record) in view of Mortensen et al. (WO 2020/254121. 2020, cited in IDS), Giwa et al. (Journal of Cleaner Production, 2019, 233:711-719, of record), Tonkovich et al. (CN 101528337, 2009, the machine-translated English version is of record), and de Mes et al. (Bio-methane & Bio-hydrogen, 2003, 58-95, of record), as applied to Claims 1-6, 12-17, and 21-22, further in view of Gundupalli et al. (Waste Management, 2017, 60:56–74, cited in IDS), as evidenced by the printout of MPa to Bar conversion (retrieved on 9/20/2024 from UnitConverters.net, of record), the printout of Bar to Psi convention (retrieved on 9/20/2024, from UnitConverters.net, of record), and Wikipedia printout of pressure swing adsorption (retrieved from the Wikipedia website on 2/20/2024, of record).
The teachings of Bradin et al., de Mes et al., Mortensen et al., Tonkovich et al. and Giwa et al. are described above.
Regarding Claim 7, Bradin et al. do not expressively teach separating a ferrous material from and reducing a size of the stream of unsorted MSW. However, Bradin et al. teach metal is one of major components in inorganic fraction in unsorted MSW (para 0082/lines 1-3), and not a part of the sorted organic fraction to be digested in the anaerobic digester (paras 0081, and 0082).
Gundupalli et al. teach methods for automated sorting unsorted MSW to obtain recycling (title, abstract), by using techniques such as: magnetic drum techniques for sorting recyclable metal materials such as ferrous materials from MSW; screw press for squeezing organic fractions in MSW stream for separating soft and wet fractions; and shredder and magnet for sorting paper and organic matter from MSW stream (page 58/paras 3-4 from bottom, page 59-60/sections (a)-(d), Fig. 3, Table 1). It noted that the use screw press and shredder results in reducing a size of the stream of unsorted MSW.
It would have been obvious to one of ordinary skill in the art to sort the stream of unsorted MSW by separating ferrous material from the stream of unsorted MSW and reducing a size of the stream (with screw press and shedder) in the method suggested by Bradin et al. and other cited prior art for obtaining a digestible organic fraction to be introduced into the anaerobic digester for biogas production, because Bradin et al. teach metal is an inorganic materiel to be separated from the organic fraction. In addition, metal including ferrous material is recyclable material, and it is a common practice in the art to separate metal including ferrous material from the unsorted MSW, as supported by Gundupalli et al. Furthermore, reducing a size of the stream of unsorted MSW (with screw press and shedder) facilitates sorting organic fraction from unsorted MSW, as supported by Gundupalli et al.
Therefore, the invention as a whole would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention.
Response to Arguments
Applicant's arguments about the claim objection in the response filed on 12/04/2025 (page 7) have been fully considered but they are not persuasive. It is noted that Applicant's amendment to the claim 23 is not sufficient to overcome the objection, because a particle’s size is a property of the particle and it is not a specific material that can be comprised in the MSW. Thus, the objection is maintained.
Applicant's arguments about the claim rejection under 35 U.S.C. 112(b) in the response filed on 12/04/2025 (pages 7-10) have been fully considered. These arguments are persuasive in part, because the amendment to the claim 1 does not resolve all the issues under 35 USC 112(b). Specifically, Applicant’s arguments based on the amendment to the steps D) and H) in the claim 1 are not persuasive because the amendment brought new issues as indicated above (see pages 3-4 for details).
Applicant's arguments about the claim rejection under 35 U.S.C. 112(d) in the response filed on 12/04/2025 (page 10) have been fully considered, but they are moot because the rejection of the claim 11 has been withdrawn, as indicated above.
Applicant's arguments about the 103 rejection of Claims 1-6, 11-17, 21-22 and 26 in the 12/04/2025 response (pages 11-15) have been fully considered but they are not persuasive for the following reasons.
In response to Applicant’s arguments based on purge gas having a hydrogen content of less than 20% in pages 14-15 of the response, these arguments are not persuasive because Applicant failed to submit any factual evidence to support that the claimed hydrogen content “less than 20 vol%” in the purge gas is critical for the anaerobic digestion of step C) in the claimed method. As indicated in the 103 rejection above, the syngas taught by Giwa has 20 vol% of hydrogen, which nearly touches the claimed content less than 20%. The combined teachings of Bradin et al., Mortensen et al., and Giwa render the claimed purge gas having less than 20 vol% of hydrogen to be obvious (see pages 7-11 of this action for details).
With regard to Applicant’s arguments based on the requirement of a large purge gas stream for preventing inert gas accumulation in pages 14-15 of the response, Examiner reminds Applicant that the instant claim 1 does not recite any limitation to require a large purge gas stream in the methanol synthesis reactor. Thus, the arguments are based on the feature not recited in the claim 1. Furthermore, it is well known in the art that a large purge gas stream is required to effectively avoid the adverse accumulation of inert gas in the methanol synthesis reactor for facilitating methanol production, as evidenced by Topf et al. described in the 103 rejection above. As such, even though the dependent claim 24 requires a large purge gas stream from a methanol synthesis reactor, the claimed invention still has no novelty in view of the status of the prior art.
Further in response to Applicant’s arguments in the paragraph spanning pages 14 and 15 of the response, a purge gas released from a methanol synthesis reactor is a syngas that has not been fully reacted in the methanol synthesis reactor and is rich in hydrogen, a major component of regular syngas; and it is well known to introduce a purge gas to anaerobic digestor for the benefits of promoting methane production and producing a biogas having a higher CH4/CO2 ratio for enhancing downstream methanol production, as supported by Mortensen et al. described above. With regard to the syngas generated by pyrolysis, Giwa et al. expressively teach that real syngas from pyrolysis does not have any toxicity to anaerobic digestion just like the simulated syngas does, as indicated above. The teachings of Giwa et al. clearly indicate the real syngas generated by pyrolysis does not contain any impurity having adverse effect on anaerobic digestion and biogas production, just like the simulated syngas does. In view of the teachings of Mortensen et al. and Giwa et al., one of ordinary skill in the art would have recognized that hydrogen in either purge gas or syngas provides the beneficial effects of promoting methane production in anaerobic digestion, thus would have been motivated to introduce the purge gas into the anaerobic digestor in the method suggested by Bradin for promoting methane production, as indicated in the 103 rejection above (see pages 7-11 for details).
As such, the combined teachings of Bradin et al., de Mes et al., Mortensen et al., Tonkovich et al. and Giwa et al. suggest each and every single element in claimed method, and render the claims 1-6, 12-17, and 21-22 to be obvious.
Applicant's arguments about the rejections of dependent claims 20, 24, 23, and 7 under 35 U.S.C. 103 in the 12/04/2025 response (pages 15-17) have been fully considered, but they are not persuasive. As indicated above, there is no deficiency in the rejection of claim 1 under 35 U.S.C. 103 over combined teachings of Bradin et al., de Mes et al., Mortensen et al., Tonkovich et al. and Giwa et al. As such, the dependent claims 20, 24, 23, and 7 comprising all limitations of claim 1 are properly rejected based on further teachings of the additional prior art, for the reasons indicated in 103 rejections above (see pages 25-34).
Overall, the conclusion of the obviousness of the claims 1-7, 12-17, and 20-24 has been established for all the reasons as indicated above.
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 extension fee 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 date of this final action.
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Any inquiry concerning this communication or earlier communications from the examiner should be directed to Qing Xu, Ph.D., whose telephone number is (571) 272-3076. The examiner can normally be reached on Monday-Friday from 9:30 AM to 5:00 PM. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Manjunath N. Rao, can be reached at (571) 272-0939. Any inquiry of a general nature or relating to the status of this application or proceeding should be directed to the receptionist whose telephone number is (571) 272-1600.
/Qing Xu/
Patent Examiner
Art Unit 1656
/MANJUNATH N RAO/Supervisory Patent Examiner, Art Unit 1656