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
Applicant’s amendment filed on March 10, 2026 has been received. Claims 2, 3, and 14 are canceled. Claims 1, 4-13, and 15-25 are under consideration.
Response to Arguments
Applicant’s arguments filed on March 10, 2026 have been fully considered.
Applicant (at pages 17-18) argues that Kresynak fails to disclose or teach the claimed means or step for adjusting the H2/CO ratio of the combined synthesis gas stream. Applicant also argues that Jahnig and Park fail to overcome the deficiencies of Kresynak.
Kresynak, however, discloses “the feedstreams for the ATR and SMR may be common or uniquely prepared in the pre-treatment unit to meet specific syngas compositions desired at 26” (at column 12, lines 49-52).
Furthermore, the newly discovered prior art reference to Heinzel et al. discloses the claimed means or step for adjusting a H2/CO ratio of the combined synthesis gas, as detailed in the rejections below.
One of ordinary skill in the art would have been motivated to provide the claimed means or step for adjusting a H2/CO ratio of the combined synthesis gas stream in the modified plant or process of Kresynak because the claimed means or step would make it possible to influence the H2/CO ratio in the combined synthesis gas stream through individual adjustment to the volume flow rates of the first and second synthesis gas stream under closed-loop control, and, as such, the H2/CO ratio of the combined synthesis gas stream can be maintained at a value preferred for the Fischer-Tropsch synthesis reaction, as taught by Heinzel. (see, e.g., paragraphs [0015], [0024]).
Applicant (at page 19, second paragraph) further argues that “… Horton does not describe adjusting the H₂/CO ratio by balancing feed gas between two reformers, let alone an electrically heated reformer and an autothermal reformer, and thus does not describe or suggest the claimed subject matter.”
The argument is not found persuasive because the secondary reference to Horton was merely relied upon to teach the claimed post processing unit comprising a post conversion unit.
Applicant (at page 20, sixth paragraph) argues, “Ahmed lacks an electrically heated reforming reactor, wherein electrical heating is the sole heating source, and Claims 1 and 13 are not obvious over Ahmed in view of Jahnig and Park for reasons similar to those set forth above in relation to the obviousness rejection based on Kresnyak in view of Jahnig and Park.”
The Office respectfully disagrees.
The primary reference to Ahmed failed to disclose or teach an electrically heated reforming reactor. Thus, the secondary references to Jahnig and Park were relied upon to teach the claimed electrically heated reforming reactor.
One of ordinary skill in the art would have been motivated to substitute the claimed electrically heated reforming reactor for the steam reforming reactor in the chemical plant or process of Ahmed because i) the electrically heated reforming reactor would not suffer from the weakening of the reformer tubes as experienced by conventional fired steam reformers operating under high temperature and pressure, as taught by Jahnig (see column 1, lines 43-62; column 2, lines 13-35); and ii) the feed gas would be uniformly distributed through passages formed by a macroscopic structure, and the flow of feed gas would be turbulent, which enhances the contact between the feed gas and the catalytically active material, as taught by Park et al. (see paragraph [0053]).
Applicant (at page 21, second paragraph) further argues, “… Allam does not describe adjusting the H2/CO ratio by balancing feed gas between two reformers, let alone an electrically heated reformer and an autothermal reformer, and thus does not describe or suggest the claimed subject matter.”
The argument is not found persuasive because Allam was merely relied upon to teach the further provision of a water gas shift unit in a post processing unit (i.e., a high temperature shift reactor R3; FIG. 1) to carry out the water gas shift reaction.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 5, 11-13, 16, 22, and 25 are rejected under 35 U.S.C. 103 as being unpatentable over Kresnyak (US 9,212,319) in view of Jahnig (US 3,147,080), Park et al. (US 2006/0014056), and Heinzel et al. (US 2017/0260457 A1).
Regarding claim 1, Kresnyak discloses a chemical plant (see embodiment of FIG. 5; column 12, lines 37-58) comprising:
a reforming section arranged to receive a feed gas comprising hydrocarbons (i.e., natural gas 12) and provide a combined synthesis gas stream (i.e., through line 26), wherein said reforming section comprises:
a reforming reactor (i.e., a steam methane reformer 25 heated by external heat energy, e.g., by burning natural gas or excess refinery gas; see column 11, lines 16-42) housing a first catalyst (see column 11, lines 42-55) and being arranged for receiving a first part of the feed gas (i.e., via stream 23) and generating a first synthesis gas stream (i.e., as syngas stream 27); and
an autothermal reforming reactor 24 in parallel with the reforming reactor 25 and housing a second catalyst (i.e., a thermal catalytic stage; see column 8, lines 4-15), said autothermal reforming reactor 24 being arranged for receiving a second part of the feed gas (i.e., via stream 22) and generating a second synthesis gas stream;
wherein the reforming section is arranged to output the combined synthesis gas stream 26 comprising at least part of the first and/or second synthesis gas stream;
an optional post processing unit (i.e., a unit of the syngas cleanup and cooling section 28) downstream the reforming section, arranged to receive the combined synthesis gas stream 26 and provide a post processed synthesis gas stream;
a water separation unit (i.e., a water separator is inherent of the chemical plant) arranged to separate said combined synthesis gas stream or said post processed synthesis gas stream into a water condensate (i.e., as a produced water stream removed at 34 to waste water 72) and an intermediate synthesis gas; and
a downstream section (i.e., a Fischer-Tropsch unit 40; see column 9, line 51, to column 10, line 21) arranged to receive the intermediate synthesis gas and process the intermediate synthesis gas to a chemical product (i.e., hydrocarbons through line 49) and an off-gas (i.e., tail gas through line 44).
Kresnyak fails to disclose the recited electrically heated reforming reactor for the reforming reactor 25, wherein electrical heating is the sole heating source.
Jahnig (see FIG. 1) discloses an apparatus comprising an electrically heated reforming reactor (i.e., a reforming reactor solely heated by resistance heating) housing a catalyst (i.e., particles of a reforming catalyst 18; see column 3, lines 11-20), wherein electrical heating is the sole heating source; said electrically heated reforming reactor being arranged for receiving a feed gas (i.e., a mixture of steam and methane, through inlet line 8) and generating a synthesis gas stream (i.e., a product gas containing H2, CO, and CO2, through outlet line 19). The reactor further comprises a pressure shell (i.e., a metal pressure shell 6) housing an electrical heating unit (i.e., an electrical resistance tubular heating element 17) arranged to heat said catalyst, wherein the catalyst 18 comprises catalytically active material operable to catalyzing steam reforming of the feed gas (i.e., a reforming catalyst such as nickel-magnesia; see column 3, lines 8-12); wherein the pressure shell 6 has a design pressure of between 5 and 45 bar (i.e., it will readily resist and withstand an interior pressure up to 1500 psig; see column 3, lines 25-30); a heat insulation layer (i.e., an insulating wall 16 of any suitable insulating material, such as high purity alumina; see column 3, lines 25-33) adjacent to at least part of the inside of the pressure shell 6; and at least two conductors (i.e., electric current leads 14 and 15) electrically connected to the electrical heating unit 17 and to an electrical power supply placed outside said pressure shell 6; wherein the electrical power supply is dimensioned to heat at least part of the catalyst to a temperature of at least 800 °C by passing an electrical current through the electrical heating unit 17 (i.e., the heating element 17 provides a temperature within the tube of between about 1400 and 1900 °F, preferably about 1600 °F; see column 3, lines 17-24); and wherein the electrical heating unit comprises a macroscopic structure of electrically conductive material (i.e., the tubular heating element 17 is made of an electrically resistant material, such as a high resistance alloy, e.g., Nichrome, or silicon carbide; see column 3, lines 3-9).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the electrically heated reforming reactor of Jahnig for the reforming reactor 25 in the chemical plant of Kresnyak because the electrically heated reforming reactor would enable the steam reforming reaction to be conducted under a combination of high temperature and pressure, which saves on the cost of compressing the product hydrogen, and the electrically heated reforming reactor would not suffer from the weakening of the reformer tubes as experienced by conventional fired steam reformers operating under high temperature and pressure, as taught by Jahnig (see column 1, lines 43-62; column 2, lines 13-35).
Jahnig fails to disclose that the macroscopic structure supports a ceramic coating, wherein the ceramic coating supports the catalytic active material.
Park et al. discloses an electrically heated reforming reactor (see FIG. 3-4; paragraphs [0041]-[0053]) comprising: a shell (i.e., a main body 21) housing an electrical heating unit (i.e., a heat generating element 26) arranged to heat a catalyst comprising a catalytic active material for reforming a feed gas (i.e., a catalyst layer 28 for catalyzing a reforming reaction of a fuel; e.g., natural gas, see paragraph [0027]); a heat insulation layer (i.e., an insulating layer 205) adjacent to at least part of the inside of the shell 21; and at least two conductors electrically connected to the electrical heating unit 26 and to an electrical power supply 29 placed outside the shell 21 (i.e., both ends of the heat-generating element 26 are connected by conductors to a power supply 29; see paragraph [0051]); and wherein the electrical power supply 29 is configured to heat at least part of the catalyst 28 to a temperature that catalyzes the reforming reaction of the fuel by passing an electrical current through the electrical heating unit 26. Specifically, the electrical heating unit 26 comprises a macroscopic structure of electrically conduct material (i.e., a pleated or corrugated metal plate; see paragraph [0049]); and wherein the macroscopic structure supports a ceramic coating (i.e., a support layer 27, such as alumina; see paragraph [0048]), and said ceramic coating 27 supports the catalytically active material 28.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further substitute the macroscopic structure of Park et al., which supports a ceramic coating, and which ceramic coating supports said catalytically active material, for the macroscopic structure that is filled with the catalytically active material in the modified chemical plant of Kresnyak because the distribution of the feed gas through the passages formed by the pleated or corrugated shape of the macroscopic structure would be uniform and the flow of the feed gas would be turbulent, thereby enhancing the contact area of the feed gas to the surface of the catalytically active material supported by the ceramic coating, as taught by Park et al. (see paragraph [0053]).
With respect to the new limitation, Kresnyak (at column 12, lines 49-52) discloses, “the feedstreams for the ATR and SMR may be common or uniquely prepared in the pre-treatment unit to meet specific syngas compositions desired at 26”. Kresnyak, however, fails to specifically disclose a means for adjusting a H2/CO ratio of the combined synthesis gas stream 26 by controlling the amount of the first part 23 of the feed gas to the reforming reactor 25 and the amount of the second part 22 of the feed gas to the autothermal reforming reactor 24.
Heinzel et al. discloses a chemical plant (see Figure) comprising:
a reforming section arranged to receive a feed gas comprising hydrocarbons (i.e., a desulphurized natural gas feed stream 2; paragraph [0024]) and provide a combined synthesis gas stream (i.e., a third synthesis gas stream 5), wherein said reforming section comprises:
a reforming reactor (i.e., a steam reforming reactor D; see paragraph [0026]), the reforming reactor D being arranged for receiving a first part (i.e., a second feed substream 4) of the feed gas and generating a first synthesis gas stream (i.e., a second synthesis gas stream 10); and
an autothermal reforming reactor (i.e., a reactor R, which can be selected as an autothermal reactor (ATR); see paragraph [0025]) in parallel with the reforming reactor D, said autothermal reforming reactor R being arranged for receiving a second part (i.e., a first feed substream 3) of said feed gas and outputting a second synthesis gas stream (i.e., a first synthesis gas stream 8);
wherein the reforming section is arranged to output the combined synthesis gas stream 5 comprising at least part of the first and/or second synthesis gas streams 10,8;
a water separation unit arranged to separate condensed water from the combined synthesis gas stream 5 to provide an intermediate synthesis gas 11 (i.e., a cooling unit K for cooling and drying the third synthesis gas stream 5; see paragraph [0028]); and
a downstream section (i.e., a Fischer-Tropsch unit F; paragraphs [0028]-[0029]) arranged to receive the intermediate synthesis gas 11 and to process the intermediate synthesis gas to a chemical product (i.e., a crude product stream 22) and an off-gas (i.e., a tailgas 17).
Specifically, Heinzel et al. (at paragraph [0024]) discloses,
“… the desulphurized feed stream 2 is divided into two feed substreams 3 and 4, it being possible to individually adjust the respective volume flow rates of these substreams, in order more particularly to set the ratio of hydrogen to carbon monoxide in the third synthesis gas stream 5.” (with emphasis added).
Heinzel et al. (at paragraph [0015]) further discloses,
“As a result of the different production methods, the first synthesis gas stream obtained by POX or ATR usually has a different composition from the second synthesis gas stream produced by steam reforming, and so it is possible to influence the ratio of hydrogen to carbon monoxide in the third synthesis gas stream obtained by combining the two streams by altering the ratios of the volume flow rates. For this purpose, for example, the division of the feed stream into the two feed substreams can be made under closed-loop control, in order to adjust the ratio of hydrogen to carbon monoxide in the synthesis gas to a given value.” (with emphasis added).
Thus, Heinzel discloses means for adjusting a H2/CO ratio of the combined synthesis gas 5 by controlling the amount of the first part 4 of the feed gas to the reforming reactor D and the amount of the second part 3 of the feed gas to the autothermal reforming reactor R.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further provide the claimed means for adjusting a H2/CO ratio of the combined synthesis gas stream in the modified plant of Kresynak because the claimed means would make it possible to influence the ratio of hydrogen-to-carbon monoxide in the combined synthesis gas stream through individual adjustment of the respective volume flow rates of the first and second synthesis gas stream under closed-loop control, and, as such, the H2/CO ratio of the combined synthesis gas stream can be maintained at a value that was preferred for the Fischer-Tropsch reaction, as taught by Heinzel et al.
Regarding claim 5, the modified plant of Kresnyak meets the claim because the further limitations only apply when the “optional steam methane reforming reactor” is present.
Regarding claim 11, Kresnyak discloses that the downstream section comprises gas separation units (i.e., a H2 separator 33; a CO2 removal unit 21) arranged to separate a stream of substantially pure CO2 (i.e., as CO2 Product) and/or H2 (i.e., via line 74) from the intermediate synthesis gas, thereby providing a refined synthesis gas (i.e., as clean syngas 30).
Regarding claim 12, Kresnyak discloses that the downstream section comprises Fischer-Tropsch reactor 40 to convert the intermediate syngas or refined syngas to a mixture of higher hydrocarbons (see column 9, line 51, to column 10, line 21).
Regarding claim 13, Kresnyak (see FIG. 5) discloses a process for producing a chemical product (i.e., Fischer-Tropsch hydrocarbons) from a feed gas comprising hydrocarbons (i.e., natural gas 12) in a chemical plant comprising a reforming section that comprises a reforming reactor (i.e., a steam methane reformer 25 heated by external heat energy, e.g., by burning natural gas or excess refinery gas; see column 11, lines 16-42) housing a first catalyst (see column 11, lines 42-55) and autothermal reforming reactor 24 in parallel with said reforming reactor 25 and housing a second catalyst (i.e., the autothermal reactor 24 comprises a thermal catalytic stage; see column 8, lines 4-15); said process comprising:
inletting a first part of the feed gas (i.e., via stream 23) to the reforming reactor 25 and carrying out steam methane reforming to provide a first synthesis gas stream (i.e., synthesis gas through stream 27);
inletting a second part of the feed gas (i.e., via stream 22) to the autothermal reforming reactor 24, and carrying out reforming to provide a second synthesis gas stream;
outputting a combined synthesis gas stream (i.e., though stream 26) comprising at least part of the first and/or second syngas stream from the reforming section;
optionally, in a post processing unit downstream the reforming reactor 25 and the autothermal reforming reactor 24 (i.e., in a unit of syngas cleanup and cooling section 28), post processing the combined synthesis gas stream 26 to provide a post processed synthesis gas stream;
separating the combined syngas stream or said post processed synthesis gas stream into a water condensate (i.e., subsequently, water is removed through line 34 and sent to waste water 72; see column 8, lines 16-18) and an intermediate synthesis gas in a water separation unit (i.e., an inherent water separator to produce water 34) downstream of the post processing unit; and
providing the intermediate synthesis gas to a downstream section (i.e., a Fischer-Tropsch Unit 40; see column 9, line 51, to column 10, line 21 to process the intermediate synthesis gas to a chemical product (i.e., Fischer Tropsch hydrocarbons, through line 49) and an off-gas (i.e., FT tailgas through line 44).
Kresnyak fails to disclose that the process uses the recited electrically heated reforming reactor for the reforming reactor 25, wherein electrical heating is the sole heating source.
Jahnig (see FIG. 1) discloses an apparatus comprising an electrically heated reforming reactor (i.e., a reforming reactor heated by resistance heating) housing a catalyst (i.e., particles of a reforming catalyst 18; see column 3, lines 11-20), wherein electrical heating is the sole heating source; said electrically heated reforming reactor being arranged for receiving a feed gas (i.e., a mixture of steam and methane, through inlet line 8) and generating a synthesis gas stream (i.e., a product gas containing H2, CO, and CO2, through outlet line 19). The reactor further comprises a pressure shell (i.e., a metal pressure shell 6) housing an electrical heating unit (i.e., an electrical resistance tubular heating element 17) arranged to heat said catalyst, wherein the catalyst 18 comprises catalytically active material operable to catalyzing steam reforming of the feed gas (i.e., a reforming catalyst such as nickel-magnesia; see column 3, lines 8-12); wherein the pressure shell 6 has a design pressure of between 5 and 45 bar (i.e., it will readily resist and withstand an interior pressure up to 1500 psig; see column 3, lines 25-30); a heat insulation layer (i.e., an insulating wall 16 of any suitable insulating material, such as high purity alumina; see column 3, lines 25-33) adjacent to at least part of the inside of the pressure shell 6; and at least two conductors (i.e., electric current leads 14 and 15) electrically connected to the electrical heating unit 17 and to an electrical power supply placed outside said pressure shell 6; wherein the electrical power supply is dimensioned to heat at least part of the catalyst to a temperature of at least 800 °C by passing an electrical current through the electrical heating unit (i.e., the heating element 17 provides a temperature within the tube of between about 1400 and 1900 °F, preferably about 1600 °F; see column 3, lines 17-24); and wherein the electrical heating unit comprises a macroscopic structure of electrically conductive material (i.e., the tubular heating element 17 is made of an electrically resistant material, such as a high resistance alloy, e.g., Nichrome, or silicon carbide; see column 3, lines 3-9). Jahnig further discloses a process of using the electrically heated reforming reactor, wherein the process comprises: pressuring the feed gas to a pressure of between 5 and 45 bar, upstream of the reactor (i.e., the gaseous mixture passes through the reactor at about 100 to 1500 psig, and preferably between about 200 to 500 psig; see column 3, lines 25-30, 37-40); and passing an electrical current through the electrical heating unit 17 thereby heating the catalyst 18 to a temperature of at least 800 °C (i.e., about 1400 and 1900 °F, preferably about 1600 °F; see column 3, lines 20-24).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the electrically heated reforming reactor of Jahnig for the reforming reactor 25 used in the process of Kresnyak, and to further perform the steps of pressuring the feed gas to a pressure of between 5 and 45 bar, upstream of the reactor, and passing an electrical current through the electrical heating unit, thereby heating the catalyst to a temperature of at least 800 °C, because the electrically heated reforming reactor would enable the steam reforming reaction to be conducted under a combination of high temperature and pressure, which saves on the cost of compressing the product hydrogen, and the electrically heated reforming reactor would not suffer from the weakening of the reformer tubes as experienced by conventional fired steam reformers operating under high temperature and pressure, as taught by Jahnig (see column 1, lines 43-62; column 2, lines 13-35).
Jahnig fails to disclose that the macroscopic structure supports a ceramic coating, and the ceramic coating supports the catalytic active material.
Park et al. discloses an electrically heated reforming reactor (see FIG. 3-4; paragraphs [0041]-[0053]) comprising: a shell (i.e., a main body 21) housing an electrical heating unit (i.e., a heat generating element 26) arranged to heat a catalyst comprising a catalytic active material for reforming a feed gas (i.e., a catalyst layer 28 for catalyzing a reforming reaction of a fuel; e.g., natural gas, see paragraph [0027]); a heat insulation layer (i.e., an insulating layer 205) adjacent to at least part of the inside of the shell 21; and at least two conductors electrically connected to the electrical heating unit 26 and to an electrical power supply 29 placed outside the shell 21 (i.e., both ends of the heat-generating element 26 are connected by conductors to a power supply 29; see paragraph [0051]); and wherein the electrical power supply 29 is configured to heat at least part of the catalyst 28 to a temperature that catalyzes the reforming reaction of the fuel by passing an electrical current through the electrical heating unit 26. Specifically, the electrical heating unit 26 comprises a macroscopic structure of electrically conduct material (i.e., a pleated or corrugated metal plate; see paragraph [0049]); and wherein the macroscopic structure supports a ceramic coating (i.e., a support layer 27, such as alumina; see paragraph [0048]), and said ceramic coating 27 supports the catalytically active material 28.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further substitute the macroscopic structure of Park et al., which supports a ceramic coating, and which ceramic coating supports said catalytically active material, for the macroscopic structure filled with the catalytically active material in the modified process of Kresnyak because the distribution of feed gas through the passages formed by the pleated or corrugated shape of the macroscopic structure would be uniform and the flow of feed gas would be turbulent, thereby enhancing the contact area of the feed gas to the surface of the catalytically active material supported by the ceramic coating, as taught by Park et al. (see paragraph [0053]).
With respect to the new limitation, Kresnyak (at column 12, lines 49-52) discloses, “the feedstreams for the ATR and SMR may be common or uniquely prepared in the pre-treatment unit to meet specific syngas compositions desired at 26”. Kresnyak, however, fails to specifically disclose a step of adjusting a H2/CO ratio of the combined synthesis gas stream 26 by controlling the amount of the first part 23 of the feed gas to the reforming reactor 25 and the amount of the second part 22 of the feed gas to the autothermal reforming reactor 24.
Heinzel et al. (see FIG. 1) discloses a process for producing a chemical product (i.e., a product stream 22; paragraph [0030]) from a feed gas comprising hydrocarbons (i.e., a desulphurized natural gas feed stream 2; paragraph [0024]), in a chemical plant comprising a reforming section, said reforming section comprising a heated reforming reactor (i.e., a steam reforming reactor D; paragraph [0026]) and an autothermal reforming reactor (i.e., a reactor R, which can comprise an autothermal reactor (ATR); paragraph [0025]) in parallel with the heated reforming reactor D; said process comprising:
inletting a first part 4 of the feed gas 2 to the heated reforming reactor D and carrying out steam methane reforming to provide a first synthesis gas stream 10;
inletting a second part 3 of the feed gas 2 to the autothermal reforming reactor R, and carrying out reforming to provide a second synthesis gas stream 8;
outputting a combined synthesis gas stream 5 comprising at least part of the first and/or second synthesis gas streams 8,10 from the reforming section;
separating water condensate from the combined synthesis gas stream in a water separation unit K (i.e., by means of cooling and drying in a cooling unit K; see paragraph [0028]) to provide an intermediate synthesis gas 11; and
providing the intermediate synthesis gas 11 to a downstream section (i.e., a Fischer-Tropsch synthesis unit F; paragraphs [0029]) arranged to receive the intermediate synthesis gas 11 and process the intermediate synthesis gas to a chemical product (i.e., the product stream 22, comprising Fischer-Tropsch synthesis products) and an off-gas (i.e., a tail gas 17).
Specifically, Heinzel et al. (at paragraph [0024]) discloses,
“… the desulphurized feed stream 2 is divided into two feed substreams 3 and 4, it being possible to individually adjust the respective volume flow rates of these substreams, in order more particularly to set the ratio of hydrogen to carbon monoxide in the third synthesis gas stream 5.” (with emphasis added).
Heinzel et al. (at paragraph [0015]) further discloses,
“As a result of the different production methods, the first synthesis gas stream obtained by POX or ATR usually has a different composition from the second synthesis gas stream produced by steam reforming, and so it is possible to influence the ratio of hydrogen to carbon monoxide in the third synthesis gas stream obtained by combining the two streams by altering the ratios of the volume flow rates. For this purpose, for example, the division of the feed stream into the two feed substreams can be made under closed-loop control, in order to adjust the ratio of hydrogen to carbon monoxide in the synthesis gas to a given value.” (with emphasis added).
Thus, Heinzel et al. discloses a step of adjusting a H2/CO ratio of the combined synthesis gas 5 by controlling the amount of the first part 4 of the feed gas to the reforming reactor D and the amount of the second part 3 of the feed gas to the autothermal reforming reactor R.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further perform the claimed step of adjusting a H2/CO ratio of the combined synthesis gas stream in the modified process of Kresynak because the individual adjustment of the respective volume flow rates of the first and second synthesis gas stream under closed-loop control would make it possible to influence the ratio of hydrogen-to-carbon monoxide in the combined synthesis gas stream, and, as such, the H2/CO ratio of the combined synthesis gas stream can be maintained at a value that was preferred for the Fischer-Tropsch reaction, as taught by Heinzel et al.
Regarding claim 16, the modified process of Kresnyak meets the claim because the limitations only apply when the “optional steam methane reforming reactor” is present.
Regarding claim 22, Kresnyak discloses separating a stream of substantially pure CO2 (i.e., CO2 Product) and/or H2 (i.e., hydrogen through line 74) from the intermediate synthesis gas in one or more gas separation units of the downstream section (i.e., in a CO2 Removal Unit 21 and a H2 separator 33), thereby provided a refined synthesis gas (i.e., as clean syngas 30).
Regarding claim 25, Kresnyak discloses that the process comprises converting said intermediate synthesis gas to a mixture of higher hydrocarbons in a Fischer-Tropsch reactor 40 (see column 9, line 51, to column 10, line 21).
Claims 9 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Kresnyak (US 9,212,319) in view of Jahnig (US 3,147,080), Park et al. (US 2006/0014056), and Heinzel et al. (US 2017/0260457 A1), as applied to claims 1 and 13 above, and further in view of Horton (GB 2168718 A).
Kresnyak fails to disclose that the post processing unit 28 (see FIG. 5) comprises a post conversion unit having an inlet for allowing addition of heated CO2 to the combined synthesis gas stream upstream the post conversion unit and housing a fifth catalyst active for catalyzing steam methane reforming, methanation, and reverse water gas shift reactions; or that the process further comprises the step of inletting heated CO2 to the combined synthesis gas upstream the post conversion unit.
Horton discloses a chemical plant comprising:
a reforming section receiving a feed gas comprising hydrocarbons and providing a synthesis gas stream (i.e., a primary process unit comprising means for converting natural gas to raw synthesis gas, such as via steam reforming or partial oxidation; see page 1, lines 10-15);
a post processing unit (i.e., a unit including means for “back shifting”; see Abstract; page 1, lines 23-34) downstream the reforming section and arranged to receive the synthesis gas stream (i.e., at very high temperature) and provide a post processed synthesis gas stream; wherein the post processing unit comprises:
a post conversion unit (i.e., a “back shift converter”) having an inlet used to perform a step of inletting heated CO2 to the synthesis gas stream upstream the post conversion unit (i.e., “High temperature gases leaving a reformer … are mixed with carbon dioxide and passed through a catalyst promoting the reaction of carbon dioxide and hydrogen to carbon monoxide and water i.e. in a back shift converter. The stream leaving the converter may be passed through a carbon dioxide removal system, the carbon dioxide removed being heated and recycled to the exit of the reformer,” see Abstract); and wherein the post conversion unit houses a fifth catalyst active for catalyzing the steam methane reforming, methanation, and reverse water gas shift reactions (i.e., a catalyst promoting the reaction of carbon dioxide and hydrogen to carbon monoxide and water (the reverse water gas shift reaction), see Abstract and page 1, lines 23-34; some of the carbon oxides are also methanated, see page 1, lines 117-122; given the presence of water and methane in the back shift converter, the steam methane reforming reaction will also inherently occur); and
a downstream section arranged to receive the synthesis gas after performing additional treatments (i.e., after performing cooling, carbon dioxide removal, and adjustments to the hydrogen/carbon monoxide ratio; see page 1, lines 125-127 and lines 89-93), wherein the downstream section is configured to process the synthesis gas to a chemical product (e.g., a Fischer-Tropsch product via a Fischer-Tropsch synthesis process; see page 1, lines 93-96).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to provide the recited post conversion unit in the modified chemical plant/process of Kresnyak because the post conversion unit would form additional carbon monoxide in the synthesis gas stream, via the reaction between the hydrogen present in the synthesis gas stream and the added carbon dioxide, so as to provide synthesis gas having a desirable composition to the downstream Fischer-Tropsch synthesis process, as taught by Horton. As suggested by Kresnyak (see column 8, lines 23-25), the additional carbon monoxide would maximize the production of the synthesis liquids product.
Claims 1, 4, 6-8, 12, 13, 15, 17-19, and 25 are rejected under 35 U.S.C. 103 as being unpatentable over Ahmed et al. (WO 2008/122399 A1), Jahnig (US 3,147,080), and Park et al. (US 2006/0014056).
Regarding claim 1, Ahmed et al. discloses a chemical plant (see FIG. 1-2; page 13, line 30, to page 15, line 18) comprising:
a reforming section arranged to receive a feed gas comprising hydrocarbons (i.e., a methane-rich gas stream 1) and provide a combined synthesis gas stream (i.e., a total syngas stream 27), the reforming section comprising:
a steam methane reforming reactor (i.e., a steam reforming reactor (SMR) 21; see also page 3, line 4, to page 4, line 3) housing a first catalyst (i.e., a catalyst in the reactor tubes), said steam methane reforming reactor 21 being arranged for receiving a first part of the feed gas (i.e., via stream 12) and generating a first synthesis gas stream (i.e., a reformed stream 22); and
an autothermal reforming reactor (ATR) 14 (see page 4, lines 13-27) in parallel with the steam methane reforming reactor 21 and housing a second catalyst (i.e., a fixed bed of catalyst in a lower part of the ATR reactor), said autothermal reforming reactor 14 being arranged for receiving a second part of the feed gas (i.e., via stream 10) and outputting a second synthesis gas stream (i.e., in an effluent stream 15);
wherein the reforming section is arranged to output the combined synthesis gas stream 27 comprising at least part of the first 22 and/or second 15 synthesis gas stream;
units for heat recovery, cooling, and compression downstream from the reforming section (see page 14, lines 29-31; page 15, lines 17-18), the units being arranged to receive the combined synthesis gas stream 27 and provide an intermediate synthesis gas; and
a downstream section (i.e., a section comprising methanol synthesis units; see page 14, lines 29-31; page 15, lines 17-18) arranged to receive the intermediate synthesis gas and process the intermediate synthesis gas to a chemical product (i.e., methanol).
Optionally (according to the embodiment shown in FIG. 2), Ahmed et al. discloses that the reforming section can be configured to comprise an optional steam methane reformer (i.e., a gas heated reactor (GHR) 18) upstream of the autothermal reforming reactor 14 (i.e., by way of line 19), such that the optional steam methane reforming reactor 18 is arranged for receiving a second part of the feed gas (i.e., via lines 11 and 17) and outputting a partially reformed second feed gas (i.e., through line 19); wherein said autothermal reforming reactor 14 is arranged for reacting said partially reformed second feed gas (i.e., received via lines 19 and 25) and outputting the second synthesis gas stream (i.e., through line 15).
Ahmed et al. does not specifically disclose an optional post processing unit or a water separation unit. Ahmed et al. also does not specifically disclose that the downstream section that produces methanol also produces off-gas. However, the Examiner takes Official Notice that the provision of an optional post processing unit for post-processing the combined synthesis gas and a water separation unit for separating water as condensate from the combined synthesis gas, in order to provide an intermediate synthesis gas that was of suitable composition for the subsequent methanol synthesis process, would have been well-known to one of ordinary skill in the chemical engineering art. Furthermore, the Examiner takes Official Notice that it is well-known in the art that a methanol synthesis section inherently produces off gas (i.e., a gas containing unreacted synthesis gas). The common knowledge or well-known in the art statements are taken to be admitted prior art because applicant has failed to traverse the examiner’s assertion of official notice. See MPEP § 2144.03.
Ahmed et al. fails to disclose the recited electrically heated reforming reactor for the steam reforming reactor 21, wherein electrical heating is the sole heating source.
Jahnig (see FIG. 1) discloses an apparatus comprising an electrically heated reforming reactor (i.e., a reforming reactor heated solely by resistance heating) housing a catalyst (i.e., a filling of particles of a conventional reforming catalyst 18; see column 3, lines 11-20), wherein electrical heating is the sole heating source; said electrically heated reforming reactor being arranged for receiving a feed gas (i.e., a mixture of steam and methane, through inlet line 8) and generating a synthesis gas stream (i.e., a product gas containing H2, CO, and CO2, through outlet line 19). The electrically heated reforming reactor further comprises a pressure shell (i.e., a metal pressure shell 6) housing an electrical heating unit (i.e., an electrical resistance tubular heating element 17) arranged to heat said catalyst, wherein the catalyst 18 comprises catalytically active material operable to catalyzing steam reforming of the feed gas (i.e., a conventional reforming catalyst such as nickel-magnesia; see column 3, lines 8-12); wherein the pressure shell 6 has a design pressure of between 5 and 45 bar (i.e., it will readily resist and withstand an interior pressure up to 1500 psig; see column 3, lines 25-30); a heat insulation layer (i.e., an insulating wall 16 of any suitable insulating material, such as high purity alumina; see column 3, lines 25-33) adjacent to at least part of the inside of the pressure shell 6; and at least two conductors (i.e., electric current leads 14 and 15) electrically connected to the electrical heating unit 17 and to an electrical power supply placed outside said pressure shell 6; wherein the electrical power supply is dimensioned to heat at least part of the catalyst to a temperature of at least 800 °C by passing an electrical current through the electrical heating unit 17 (i.e., the heating element 17 provides a temperature within the tube of between about 1400 and 1900 °F, preferably about 1600 °F; see column 3, lines 17-24); and wherein the electrical heating unit comprises a macroscopic structure of electrically conductive material (i.e., the tubular heating element 17 is made of an electrically resistant material, such as a high resistance alloy, e.g., Nichrome, or silicon carbide; see column 3, lines 3-9).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the electrically heated reforming reactor of Jahnig for the steam methane reforming reactor 21 in the chemical plant of Ahmed et al. because the electrically heated reforming reactor would enable the steam reforming reaction to be conducted under a combination of high temperature and pressure, which saves on the cost of compressing the product hydrogen, and the electrically heated reforming reactor would not suffer from the weakening of the reformer tubes as experienced by conventional fired steam reformers operating under high temperature and pressure, as taught by Jahnig (see column 1, lines 43-62; column 2, lines 13-35).
Jahnig fails to disclose that the macroscopic structure supports a ceramic coating, wherein the ceramic coating supports the catalytic active material.
Park et al. discloses an electrically heated reforming reactor (see FIG. 3-4; paragraphs [0041]-[0053]) comprising: a shell (i.e., a main body 21) housing an electrical heating unit (i.e., a heat generating element 26) arranged to heat a catalyst comprising a catalytic active material for reforming a feed gas (i.e., a catalyst layer 28 for catalyzing a reforming reaction of a fuel; e.g., natural gas, see paragraph [0027]); a heat insulation layer (i.e., an insulating layer 205) adjacent to at least part of the inside of the shell 21; and at least two conductors electrically connected to the electrical heating unit 26 and to an electrical power supply 29 placed outside the shell 21 (i.e., both ends of the heat-generating element 26 are connected by conductors to a power supply 29; see paragraph [0051]); and wherein the electrical power supply 29 is configured to heat at least part of the catalyst 28 to a temperature that catalyzes the reforming reaction of the fuel by passing an electrical current through the electrical heating unit 26. Specifically, the electrical heating unit 26 comprises a macroscopic structure of electrically conduct material (i.e., a pleated or corrugated metal plate; see paragraph [0049]); and wherein the macroscopic structure supports a ceramic coating (i.e., a support layer 27, such as alumina; see paragraph [0048]), and said ceramic coating 27 supports the catalytically active material 28.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the macroscopic structure of Park et al., which supports a ceramic coating, and which ceramic coating supports said catalytically active material, for the macroscopic structure that is filled with the catalytically active material in the modified chemical plant of Ahmed et al. because the distribution of the feed gas through the passages formed by the pleated or corrugated shape of the macroscopic structure would be uniform, and the flow of the feed gas would be turbulent, thereby enhancing the contact area of the feed gas to the surface of the catalytically active material supported by the ceramic coating, as taught by Park et al. (see paragraph [0053]).
With respect to the new limitation, Ahmed et al. (at page 11, lines 26-30) discloses,
“The heated pre-reformed gas stream is then divided into three streams that are fed to the reforming reactors operated in parallel; that is one stream is fed to an ATR, a second stream to a SMR, and the third stream to a GHR …The gas distribution rates to the different reformers are depending on the actual process scheme applied.” (with emphasis added).
Ahmed et al. (at page 16, lines 16-20) further discloses,
“Preferably, in the process according to the invention the gas distribution rates, and operating conditions of the reformers are adjusted, within above indicated ranges, such that the composition of the syngas product stream is suitable for subsequent use in methanol synthesis; i.e. preferably the syngas mixture has a SN of 2.0-2.2, more preferably SN is 2.0-2.1.” (with emphasis added).
The stoichiometric number (SN) represents the hydrogen-to-carbon monoxide content of the synthesis gas composition (see page 2, lines 7-13).
Therefore, Ahmed et al. further discloses a means for adjusting a H2/CO ratio of the combined synthesis gas from the reforming section (i.e., as represented SN) by controlling the amount of the first part of the feed gas to the steam methane reforming reactor 21 and the amount of the second part of the feed gas to the autothermal reforming reactor 14 (i.e., by adjusting the gas distribution rates of the feed gas to the respective reforming reactors 21, 14).
Regarding claim 4, Ahmed et al. discloses a heat exchanger 8 upstream said autothermal reforming reactor 14, the heat exchanger being arranged to preheat the second part 10 of the feed gas (see page 14, lines 8-10). Ahmed et al., however, fails to disclose that a fired heater unit is used for preheating the second part of the feed gas, instead of the heat exchanger 8.
Jahnig discloses that, normally, the feed gas will be preheated before going to the electrically heated reforming reactor, wherein the preheating can be conducted by heat exchange with hot products or, alternatively, in a fired heater unit (i.e., a separately fired furnace; see column 2, lines 57-65).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute a fired heater unit for the heat exchanger in the modified chemical plant of Ahmed et al. because a fired heater unit was considered a suitable alternative to a heat exchanger for providing substantially the same result of preheating the feed gas to the required reforming reaction temperature, as taught by Jahnig.
Ahmed et al. further discloses various couplings between the downstream section and the reforming section to optimize the consumption of feedstock and energy. For instance, unreacted syngas components (i.e., off-gas) from methanol synthesis in the downstream section can be used as fuel in the reforming section (see page 16, line 31, to page 17, line 2).
Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to provide a means for recycling at least part of the off-gas from the downstream section as fuel for use in the fired heater unit in the modified chemical plant of Ahmed et al. because the off-gas from the downstream was usable as fuel, and the recycling of the off-gas from the downstream section to the fired heater unit in the reforming section would optimize the consumption of fuel in the chemical plant.
Regarding claim 6, Ahmed et al. discloses that the reforming section (according to FIG. 1) further comprises: a gas heated steam methane reforming reactor (i.e., a gas heated reactor (GHR) 18) parallel to the steam methane reforming reactor 21 and the autothermal reforming reactor 14, wherein the gas heated steam methane reforming reactor 18 comprises a fourth catalyst (i.e., a reforming catalyst at the tube-side) and is operable to receive a third part of the feed gas (i.e., via stream 11) and to utilize at least part of the first and/or second synthesis gas streams as heating media in heat exchange within the gas heated steam methane reforming reactor (i.e., the effluent stream 15 from the ATR 14 is fed to a shell side of the GHR 18 for heating the catalyst in the tube side of the GHR 18), said gas heated steam methane reforming reactor 18 being arranged for generating a third synthesis gas stream (i.e., a reformed stream 19) and outputting the third synthesis gas stream from the reforming section as at least part of the combined synthesis gas stream 27.
Regarding claim 7, Ahmed et al. discloses that the reforming section (according to FIG. 2) further comprises: a gas heated steam methane reforming reactor (i.e., a gas heated reactor (GHR) 18) upstream of the autothermal reforming reactor 14 (i.e., the GHR 18 is upstream of the ATR 14 relative to the flow of an effluent stream 19 from the GHR 18 to the ATR 14); wherein the gas heated steam methane reforming reactor 18 comprises a fourth catalyst (i.e., a reforming catalyst at the tube-side) and is operable to utilize at least part of the second synthesis gas stream (i.e., the effluent stream 15) as heating media in heat exchange within the gas heated steam methane reforming reactor 18 (i.e., the effluent stream 15 from the ATR 14 is fed to a shell side of the GHR 18 for heating the catalyst in the tube side of the GHR 18), said gas heated steam methane reforming reactor 18 being arranged to receive a second part of the feed gas (i.e., now interpreted as the stream 11) and to provide a partially reformed second feed gas (i.e., in the effluent stream 19), and wherein the partially reformed second feed gas 19 is led to the autothermal reforming reactor 14 (i.e., by way of line 25).
Regarding claim 8, Ahmed et al. discloses that the reforming section can be further configured to utilize at least part of the first synthesis gas stream (i.e., the reformed gas 22) as heating media in heat exchange within the gas heated steam methane reforming reactor 18 (i.e., when the reformed gas 22 from the SMR 21 is routed via lines 24 and 25 to the ATR 14 and via line 15 to the shell-side of the GHR 18; see FIG. 3).
Regarding claim 12, as mentioned above, the downstream section comprises a methanol reactor to convert the intermediate synthesis gas to methanol. Ahmed et al. also discloses that, besides methanol, the intermediate synthesis gas can be converted to other chemical products, such as ammonia or Fischer-Tropsch hydrocarbons (see column 18, lines 5-10). Accordingly, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to alternatively provide an ammonia reactor or a Fischer-Tropsch reactor in the downstream section in the modified chemical plant of Ahmed et al., depending on the intended chemical product desired.
Regarding claim 13, Ahmed et al. discloses a process for producing a chemical product (i.e., methanol) from a feed gas comprising hydrocarbons (i.e., a methane-rich gas stream) in a chemical plant comprising a reforming section (see FIG. 1-2; page 13, line 30, to page 15, line 18), as detailed in claim 1. Ahmed et al. further discloses that the process comprises:
inletting a first part of the feed gas (i.e., via stream 12) to the steam reforming reactor 21 and carrying out steam methane reforming to provide a first synthesis gas stream (i.e., reformed gas 22);
inletting a second part of the feed gas (i.e., via stream 10) to the autothermal reforming reactor 14 and carrying out reforming to provide a second synthesis gas stream (i.e., in effluent stream 15);
outputting a combined synthesis gas stream (i.e., the total syngas stream 27) comprising at least part of the first 22 and/or second 15 synthesis gas stream from the reforming section;
recovering heat, cooling, and compressing the combined synthesis gas stream to provide an intermediate stream (see page 14, lines 29-31; page 15, lines 17-18); and
providing the intermediate synthesis gas to a downstream section (i.e., a section comprising methanol synthesis units; see page 14, lines 29-31; page 15, lines 17-18) arranged to receive the intermediate synthesis gas and process the intermediate synthesis gas to the chemical product (i.e., methanol).
Optionally (according to the embodiment in FIG. 2), the reforming section comprises an optional steam methane reforming reactor (i.e., a gas heated reactor (GHR) 18) upstream from said autothermal reforming reactor 14 (i.e. by way of line 19); such that the process comprises inletting a second part of the feed gas (i.e., via lines 11 and 17) to said optional steam methane reforming reactor 18 and outputting a partially reformed second feed gas (i.e., through line 19), which is supplied (i.e., via lines 19 and 25) to the autothermal reforming reactor 14 to provide the second synthesis gas stream (i.e., through line 15).
Ahmed et al. does not specifically disclose an optional post processing step or a water separation step. Ahmed et al. also does not specifically disclose that the downstream section produces off-gas. However, the Examiner takes Official Notice that the provision of an optional post processing step to post process the combined synthesis gas and a water separation step to separate water as condensate from the combined synthesis gas, in order to provide an intermediate synthesis gas of a suitable composition for the subsequent methanol synthesis process, would have been well-known to one of ordinary skill in the chemical engineering art. The Examiner also takes Official Notice that it is well-known in the art that a methanol synthesis section produces off gas (i.e., a gas containing unreacted synthesis gas). The common knowledge or well-known in the art statements are taken to be admitted prior art because applicant has failed to traverse the examiner’s assertion of official notice. See MPEP § 2144.03.
Ahmed et al. fails to disclose the recited electrically heated reforming reactor for the steam methane reforming reactor 21, wherein electrical heating is the sole heating source.
Jahnig (see FIG. 1) discloses an apparatus comprising an electrically heated reforming reactor (i.e., a reforming reactor heated solely by resistance heating) housing a catalyst (i.e., a reforming catalyst 18; column 3, lines 11-20), wherein electrical heating is the sole heating source; said reactor being arranged for receiving a feed gas (i.e., a mixture of steam and methane through line 8) and generating a synthesis gas stream (i.e., through line 19). The reactor further comprises a pressure shell (i.e., a metal pressure shell 6) housing an electrical heating unit (i.e., an electrical resistance tubular heating element 17) to heat said catalyst, wherein the catalyst 18 comprises catalytically active material for catalyzing steam reforming of the feed gas (i.e., a reforming catalyst such as nickel-magnesia; column 3, lines 8-12); wherein the pressure shell 6 has a design pressure of between 5 and 45 bar (i.e., to resist and withstand an interior pressure up to 1500 psig; column 3, lines 25-30); a heat insulation layer (i.e., an insulating wall 16 of any suitable insulating material, such as high purity alumina; column 3, lines 25-33) adjacent to at least part of the inside of the pressure shell 6; and at least two conductors (i.e., electric current leads 14,15) electrically connected to the electrical heating unit 17 and to an electrical power supply outside said pressure shell 6; wherein the electrical power supply is dimensioned to heat at least part of the catalyst to a temperature of at least 800 °C by passing an electrical current through the electrical heating unit (i.e., a temperature within the tube of between about 1400 and 1900 °F, preferably about 1600 °F; column 3, lines 17-24); and the electrical heating unit comprises a macroscopic structure of electrically conductive material (i.e., the heating element 17 is made of an electrically resistant material, e.g., Nichrome or silicon carbide; column 3, lines 3-9). Jahnig also discloses a process of using the electrically heated reforming reactor, comprising: pressuring the feed gas to a pressure of between 5 and 45 bar, upstream of the reactor (i.e., at about 100 to 1500 psig, and preferably between about 200 to 500 psig; column 3, lines 25-30, 37-40); and passing an electrical current through the electrical heating unit 17 thereby heating the catalyst 18 to a temperature of at least 800 °C (i.e., about 1400 to 1900 °F, and preferably about 1600 °F; column 3, lines 20-24).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the electrically heated reforming reactor of Jahnig for the reforming reactor 21 in the process of Ahmed et al., and to further perform the steps of pressuring the feed gas to a pressure of between 5 and 45 bar, upstream of the electrically heated reforming reactor, and passing an electrical current through the electrical heating unit to heat the catalyst to at least 800 °C, because the electrically heated reforming reactor would enable the steam reforming reaction to be conducted under a combination of high temperature and pressure, which saves on the cost of compressing the product hydrogen, and the electrically heated reforming reactor would not suffer from the weakening of the reformer tubes as experienced by conventional fired steam reformers operating under high temperature and pressure, as taught by Jahnig (see column 1, lines 43-62; column 2, lines 13-35).
Jahnig fails to disclose that the macroscopic structure supports a ceramic coating, and the ceramic coating supports the catalytic active material.
Park et al. discloses an electrically heated reforming reactor (see FIG. 3-4; paragraphs [0041]-[0053]) comprising: a shell (i.e., a main body 21) housing an electrical heating unit (i.e., a heat generating element 26) arranged to heat a catalyst comprising a catalytic active material for reforming a feed gas (i.e., a catalyst layer 28 for catalyzing a reforming reaction of a fuel; e.g., natural gas, see paragraph [0027]); a heat insulation layer (i.e., an insulating layer 205) adjacent to at least part of the inside of the shell 21; and at least two conductors electrically connected to the electrical heating unit 26 and to an electrical power supply 29 placed outside the shell 21 (i.e., both ends of the heat-generating element 26 are connected by conductors to a power supply 29; paragraph [0051]); and wherein the electrical power supply 29 is configured to heat at least part of the catalyst 28 to a temperature that catalyzes the reforming reaction of the fuel by passing an electrical current through the electrical heating unit 26. Specifically, the electrical heating unit 26 comprises a macroscopic structure of electrically conduct material (i.e., a pleated or corrugated metal plate; paragraph [0049]); wherein the macroscopic structure supports a ceramic coating (i.e., a support layer 27, such as alumina; paragraph [0048]), and said ceramic coating 27 supports the catalytically active material 28.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the macroscopic structure of Park et al., which supports a ceramic coating, and which ceramic coating supports said catalytically active material, for the macroscopic structure filled with the catalytically active material in the modified process of Ahmed et al. because the distribution of feed gas through the passages formed by the pleated or corrugated shape of the macroscopic structure would be uniform, and the flow of feed gas would be turbulent, thereby enhancing the contact area of the feed gas to the surface of the catalytically active material supported by the ceramic coating, as taught by Park et al. (see paragraph [0053]).
With respect to the new limitation, Ahmed et al. (at page 11, lines 26-30) discloses,
“The heated pre-reformed gas stream is then divided into three streams that are fed to the reforming reactors operated in parallel; that is one stream is fed to an ATR, a second stream to a SMR, and the third stream to a GHR …The gas distribution rates to the different reformers are depending on the actual process scheme applied.” (with emphasis added).
Ahmed et al. (at page 16, lines 16-20) further discloses,
“Preferably, in the process according to the invention the gas distribution rates, and operating conditions of the reformers are adjusted, within above indicated ranges, such that the composition of the syngas product stream is suitable for subsequent use in methanol synthesis; i.e. preferably the syngas mixture has a SN of 2.0-2.2, more preferably SN is 2.0-2.1.” (with emphasis added).
The stoichiometric number (SN) represents the hydrogen-to-carbon monoxide content of the synthesis gas composition (see page 2, lines 7-13).
Therefore, Ahmed et al. further discloses adjusting a H2/CO ratio of the combined synthesis gas from the reforming section (i.e., as represented SN) by controlling the amount of the first part of the feed gas to the steam methane reforming reactor 21 and the amount of the second part of the feed gas to the autothermal reforming reactor 14 (i.e., by adjusting the gas distribution rates of the feed gas to the respective reforming reactors 21, 14).
Regarding claim 15, Ahmed et al. further discloses preheating the second part 10 of the feed gas using a heat exchanger 8 upstream said autothermal reforming reactor 14 (see page 14, lines 8-10). Ahmed et al., however, fails to disclose that a fired heater unit is used for preheating the second part of the feed gas, instead of the heat exchanger 8.
Jahnig discloses that, normally, the feed gas will be preheated before going to the electrically heated reforming reactor, wherein the preheating can be conducted by heat exchange with hot products or, alternatively, in a fired heater unit (i.e., in a separately fired furnace; see column 2, lines 57-65).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute a fired heater unit for the heat exchanger for preheating the second part of the feed gas in the modified process of Ahmed et al. because a fired heater unit was considered a suitable alternative to a heat exchanger for providing substantially the same result of preheating the feed gas to the required reforming reaction temperature, as taught by Jahnig.
Ahmed et al. further discloses various couplings between the downstream section and the reforming section to optimize the consumption of feedstock and energy. For instance, unreacted syngas components (i.e., off-gas) from methanol synthesis in the downstream section can be recycled as fuel in the reforming section (see page 16, line 31, to page 17, line 2).
Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to recycle at least a part of the off-gas from the downstream section as fuel to the fired heater unit in the modified process of Ahmed et al. because the off-gas from the downstream was usable as fuel, and the recycling of the off-gas from the downstream section to the fired heater unit in the reforming section would optimize the consumption of fuel in the chemical plant.
Regarding claim 17, Ahmed et al. discloses that the reforming section (according to FIG. 1) further comprises a gas heated steam methane reforming reactor (i.e., a gas heated reactor (GHR) 18) parallel to the steam methane reforming reactor 21 and the autothermal reforming reactor 14, wherein the gas heated steam methane reforming reactor 18 comprises a fourth catalyst (i.e., tube-side); and said process further comprises the steps of:
inletting a third part of the feed gas (i.e., via stream 11) into the gas heated steam methane reforming reactor 18;
utilizing at least part of the first and/or second synthesis gas stream as heating media in heat exchange with the gas heated steam methane reforming reactor (i.e., the effluent stream 15 from the autothermal reforming reactor 14 is fed to a shell side of the gas heated reactor 18 for heating the catalyst in the tube side of the gas heated reactor 18);
generating a third synthesis gas stream (i.e., a reformed stream 19) over the fourth catalyst within the gas heated steam methane reforming reactor 18; and
outputting the third synthesis gas stream 19 from the reforming section as at least part of the combined synthesis gas 27.
Regarding claim 18, Ahmed et al. discloses that the optional steam methane reforming reactor (according to FIG. 2) is a gas heated steam methane reforming reactor (i.e., a gas heated reactor (GHR) 18) upstream of said autothermal reforming reactor 14 (i.e., the GHR 18 is upstream of the ATR 14 relative to the flow of an effluent stream 19 from the GHR 18 to the ATR 14), wherein the gas heated steam methane reforming reactor 18 comprises a fourth catalyst (i.e., tube side), and the process further comprises the steps of:
inletting the second part of the feed gas (i.e., now interpreted as stream 11) into the gas heated steam methane reformer 18, and carrying out steam methane reforming within the gas heated steam methane reformer 18 to provide a partially reformed second feed gas (i.e., in the effluent stream 19);
providing the partially reformed second feed gas 19 to the autothermal reforming reactor 14 (i.e., by way of line 25); and
utilizing at least part of the second synthesis gas stream (i.e., the effluent stream 15) as heating media in heat exchange within the gas heated steam methane reformer 18 (i.e., the effluent stream 15 from the ATR 14 is fed to a shell side of the GHR 18 for heating the catalyst in the tube side of the GHR 18).
Regarding claim 19, Ahmed et al. discloses the further step of utilizing at least part of the first synthesis gas stream 22 as heating media in heat exchange within the gas heated steam methane reforming reactor 18 (i.e., when the reformed gas 22 from the SMR 21 is routed via lines 24 and 25 to the ATR 14 and via line 15 to the shell side of the GHR 18; see FIG. 3).
Regarding claim 25, as mentioned above, the process comprises converting the intermediate synthesis gas to methanol in a methanol reactor. Ahmed et al. also discloses that the intermediate synthesis gas can be converted to other chemical products such as ammonia or Fischer-Tropsch hydrocarbons (see column 18, lines 5-10). Thus, it would have also been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to convert the intermediate synthesis gas to ammonia in an ammonia reactor or a mixture of higher hydrocarbons in a Fischer-Tropsch reactor in the downstream section in modified process of Ahmed et al., depending on the intended chemical product desired.
Claims 10 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over Ahmed et al. (WO 2008/122399 A1) in view of Jahnig (US 3,147,080), and Park et al. (US 2006/0014056), as applied to claims 1 and 13 above, and further in view of Allam et al. (US 2002/0103264).
Ahmed et al. fails to disclose a water gas shift unit in the optional post processing unit, wherein the water gas shift unit is arranged to carry out the water gas shift reaction.
Allam et al. (Figure 1) discloses a chemical plant comprising a reforming section (i.e., a partial oxidation reformer POX R1 and a gas heated catalytic reformer GHR R2) arranged to receive a feed gas comprising hydrocarbons (i.e., natural gas 1) and provide a combined synthesis gas stream (i.e., a product stream 6); an optional post processing unit (i.e., an optional high temperature shift reactor R3 in a second portion 9, which may be bypassed via a first portion 8) downstream the reforming section, where said optional post processing unit R3 is arranged to receive the combined synthesis gas stream and provide a post processed synthesis gas stream (i.e., an intermediate hydrogen-enriched synthesis gas stream 10); a water separation unit (i.e., a unit including condenser X4 and separator vessel C1) arranged to separate the combined synthesis gas stream or the post processed synthesis gas stream 11 into a water condensate (i.e., a water by-product stream 52) and an intermediate synthesis gas (i.e., a water-depleted synthesis gas stream 14); and a downstream section (i.e., a Fischer-Tropsch reactor R4, paragraphs [0083]-[0084]; or a methanol synthesis reactor, paragraphs [0001], [0056]-[0061])) to receive the intermediate synthesis gas and to process the intermediate synthesis gas to a chemical product (i.e., a condensed product stream 18) and an off-gas (i.e., an uncondensed by-product stream 21 usable as fuel; see paragraph [0086]). Specifically, Allam discloses that the optional post processing unit comprises a water gas shift unit (i.e., high temperature shift reactor R3; paragraph [0080]) to carry out the water gas shift reaction.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to provide a water gas shift unit in the optional post processing unit in the modified plant and process of Ahmed et al. because the water gas shift unit would allow for the ratio of hydrogen-to-carbon monoxide in the combined synthesis gas stream to be adjusted, when necessary, to a ratio that was appropriate for the process to be conducted in the downstream section, as taught by Allam et al. (see paragraph [0080]).
Allowable Subject Matter
Claims 5 and 16 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims, and to recite that the steam methane reforming reactor upstream the autothermal reforming reaction is present (i.e., not “optional”).
Claim 23 is allowed. Claim 24 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
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.
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/JENNIFER A LEUNG/Primary Examiner, Art Unit 1774
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