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 .
Detailed Action
This office action is in response to applicant’s communication filed on 5/18/26.
Claims 20-40 are pending in this application. Claims 20-36 remain withdrawn.
Due to applicant’s new and amended claims filed 5/18/26, the objection, 112 and 103 rejections are withdrawn. However, a revised 103 rejections are in order which are included below. As a result, claims 37-40 are being examined in this Office Action.
Claim Rejections – 35 USC 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
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 37-38 and 40 are rejected under 35 U.S.C. 103 as being unpatentable over Singh (US 20100016635, pub date Jan. 21, 2010).
Determination of the Scope and Content of the Prior Art
(MPEP §2141.01)
Singh teaches an integrated ammonia-urea process, in which heat is exchanged from a syngas reaction of hydrocarbon, hydrogen and carbon monoxide, which produces ammonia, to a urea solution of urea and ammonium carbamate. Singh teaches the heat can decompose and dehydrate the ammonium carbamate to form the urea. Singh also teaches the formation of syngas by reforming hydrocarbons. (page 1, abstract; figures 1-3; paragraphs 1-6, 9-10, 15, 24-44; claims 1-4).
Singh teaches some of the purified syngas containing ammonia and carbon dioxide are used in the integrated urea synthesis, in which ammonium carbamate is decomposed and dehydrated. (page 1, abstract; figures 1-3; paragraphs 9-10, 15, 24-44).
Singh teaches steam as a heat transfer medium in the integrated ammonia-urea process. Singh teaches the use of steam to heat the urea solution and to decompose ammonium carbamate. Singh teaches steam line 107 can be introduced to heat exchanger 101 for heating the urea solution. (paragraphs 24, 35; figure 1).
Singh teaches steam production and use in the ammonia/syngas section. For example, Singh teaches the syngas can be quenched in a heat/steam/heat exchanger to generate steam, and the steam can be introduced to the steam reformer. (paragraphs 59-60; figure 3).
Singh also teaches steam production and use in the urea section. Singh teaches steam can be generated from the purification of urea. Singh further teaches low pressure steam in connection with ammonium carbamate recovery. (paragraphs 52-53; figure 2).
Singh teaches a range of pressures in the synthesis, purification and recovery sections. The urea is synthesized at high pressure to form ammonium carbamate, which is dehydrated with heat to form urea and water. Singh teaches medium pressure and low pressure ammonium carbamate decomposers, and medium pressure and low pressure ammonium carbamate condensers. (paragraphs 49-53, 78, 96-97; figures 1-3).
Singh teaches a “large amount of energy in the form of heat (e.g. steam) and pressure (e.g. compressors) are required to operate the urea section, and other economically negative impacts are present.” (paragraph 6).
The pressure of the steam can vary. Singh teaches pressure ranges of 10 kg/cm2 to about 15 kg/cm2 (or about 10 bar to 15 bar) and ranges of 15 kg/cm2 to 25 kg/cm2 (or about 15 bar to 25 bar). Singh also teaches a low pressure steam line that comes from ammonium carbamate recovery at about 700 kPa, and also teaches low pressure recovery from about 250 kPa to 600 kPa (or about 2.5 bar to 6.5 bar). (paragraphs 24, 35, 52-53; claims 3-4 and 17).
With regard to applicant’s limitation for “recovery of unconverted matter”, it would be reasonable to expect this to read on the unconverted ammonium carbamate in the urea solution that did not completely decompose and condense in the urea synthesis, absent evidence to the contrary.
As to claim 38 and claim 40, Singh teaches self-stripping or ammonia-stripping and recovery performed at two pressure levels, including a medium pressure and a low pressure. Singh teaches medium pressure and low pressure ammonium carbamate decomposers and medium pressure and low pressure ammonium carbamate condensers. Singh also teaches use of steam for decomposition of ammonium carbamate in the recovery of urea. (paragraphs 49-53, 78, 96-97; figures 1-3).
Ascertainment of the Difference Between Scope the Prior Art and the Claims
(MPEP §2141.012)
Singh is deficient in the sense that it does not expressly teach applicant’s low pressure steam of not greater than 6 bar rel, transferred from the ammonia section to the urea section, for use in at least one steam user in the urea section.
Singh is further deficient in the sense that it does not expressly teach that said steam transferred from the ammonia section to the urea section is used for carbamate decomposition in the medium-pressure recovery.
Instead, Singh teaches an integrated ammonia-urea process, steam production and use in the ammonia/syngas section, steam production and use in the urea section, heat transfer to the urea solution, steam use for ammonium carbamate decomposition, and pressure values for steam and recovery sections including medium pressure and low pressure values. (paragraphs 6, 24, 35, 49-53, 59-60, 78, 96-97; figures 1-3; claims 3-4 and 17).
Finding of Prima Facie Obviousness Rationale and Motivation
(MPEP §2142-2143)
However, it would be prima facie obvious to one of ordinary skill in the art at the time of the invention, to use the steam generated in Singh’s ammonia/syngas section as available steam for the integrated ammonia-urea process, including by transferring steam from the ammonia section to the urea section, since Singh teaches an integrated ammonia-urea process and teaches steam production and steam use in the ammonia/syngas section and in the urea section.
Furthermore, it would have been obvious to use the transferred steam for carbamate decomposition in the medium pressure recovery, since Singh teaches that steam is used to heat the urea solution and decompose ammonium carbamate, and Singh teaches medium pressure and low pressure ammonium carbamate decomposers and condensers in the recovery of urea.
Furthermore, it would be prima facie obvious to one of ordinary skill in the art at the time of the invention, to use steam at a lower pressure in Singh’s integrated ammonia-urea process, since Singh teaches that the pressure of the steam can vary and Singh teaches low pressure steam in the urea recovery section. Singh also recognizes that a large amount of energy in the form of heat, such as steam, and pressure, such as compressors, are required to operate the urea section, and other economically negative impacts are present. Since lowering the pressure of the steam would lower the energy needed, one would be motivated by economic concerns to lower the pressure of the steam.
Additionally, to the extent the claimed pressure is “6 bar rel”, Singh’s 700 kPa steam pressure corresponds to about 7 bar absolute pressure, which is approximately 6 bar relative pressure. Thus, Singh teaches or at least renders obvious steam pressure close to or corresponding to the claimed low pressure value.
Additionally merely modifying process conditions such as the pressure is not a patentable modification, absent a showing of criticality. In re Aller, 220 F.2d 454, 105 U.S.P.Q. 233 (C.C.P.A. 1955). Generally, differences in process conditions will not support the patentability of subject matter encompassed by the prior art. Such formulations are result-effective variables which can be optimized. In re Boesch, 617 F.2d 272, 276, 205 USPQ 215, 219 (CCPA 1980), it was held that “discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art.” Further, in In re Aller, 220 F.2d454, 456, 105 USPQ 233,235 (CCPA 1955) the courts maintained that: “Where the general condition of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.”
Thus since pressure is a result-effective variable, it is the position of the examiner that one of ordinary skill in the art, at the time of the invention, would through routine and normal experimentation determine the appropriate steam pressure used in the integrated ammonia-urea plant.
Therefore, claims 37-38, and 40 are unpatentable over Singh.
Claims 37-38, and 39 are rejected under 35 U.S.C. 103 as being unpatentable over Singh (US 20100016635, pub date Jan. 21, 2010).
Determination of the Scope and Content of the Prior Art
(MPEP §2141.01)
Singh teaches an integrated ammonia-urea process, in which heat is exchanged from a syngas reaction of hydrocarbon, hydrogen and carbon monoxide, which produces ammonia, to a urea solution of urea and ammonium carbamate. Singh teaches the heat can decompose and dehydrate the ammonium carbamate to form the urea. Singh also teaches the formation of syngas by reforming hydrocarbons. (page 1, abstract; figures 1-3; paragraphs 1-6, 9-10, 15, 24-44; claims 1-4).
Singh teaches some of the purified syngas containing ammonia and carbon dioxide are used in the integrated urea synthesis, in which ammonium carbamate is decomposed and dehydrated. (page 1, abstract; figures 1-3; paragraphs 9-10, 15, 24-44).
Singh teaches steam as a heat transfer medium in the integrated ammonia-urea process. Singh teaches the use of steam to heat the urea solution and to decompose ammonium carbamate. Singh teaches steam line 107 can be introduced to heat exchanger 101 for heating the urea solution. (paragraphs 24, 35; figure 1).
Singh teaches steam production and use in the ammonia/syngas section. For example, Singh teaches the syngas can be quenched in a heat/steam/heat exchanger to generate steam, and the steam can be introduced to the steam reformer. (paragraphs 59-60; figure 3).
Singh also teaches steam production and use in the urea section. Singh teaches steam can be generated from the purification of urea. Singh further teaches low pressure steam in connection with ammonium carbamate recovery. (paragraphs 52-53; figure 2).
Singh teaches a range of pressures in the synthesis, purification and recovery sections. The urea is synthesized at high pressure to form ammonium carbamate, which is dehydrated with heat to form urea and water. Singh teaches medium pressure and low pressure ammonium carbamate decomposers, and medium pressure and low pressure ammonium carbamate condensers. (paragraphs 49-53, 78, 96-97; figures 1-3).
Singh teaches a “large amount of energy in the form of heat (e.g. steam) and pressure (e.g. compressors) are required to operate the urea section, and other economically negative impacts are present.” (paragraph 6).
The pressure of the steam can vary. Singh teaches pressure ranges of 10 kg/cm2 to about 15 kg/cm2 (or about 10 bar to 15 bar) and ranges of 15 kg/cm2 to 25 kg/cm2 (or about 15 bar to 25 bar). Singh also teaches a low pressure steam line that comes from ammonium carbamate recovery at about 700 kPa, and also teaches low pressure recovery from about 250 kPa to 600 kPa (or about 2.5 bar to 6.5 bar). (paragraphs 24, 35, 52-53; claims 3-4 and 17).
With regard to applicant’s limitation for “recovery of unconverted matter”, it would be reasonable to expect this to read on the unconverted ammonium carbamate in the urea solution that did not completely decompose and condense in the urea synthesis, absent evidence to the contrary.
As to claim 38 and claim 39, Singh teaches a CO2-stripping process and low pressure recovery. Singh teaches use of steam in a CO2 stripped syngas process and teaches one or more ammonium carbamate recovery units and decomposers can operate at low pressure. Singh also teaches low pressure steam comes from ammonium carbamate recovery. (paragraphs 44, 49-53, 78, 96-97; figures 1-3).
Ascertainment of the Difference Between Scope the Prior Art and the Claims
(MPEP §2141.02)
Singh is deficient in the sense that it does not expressly teach applicant’s low pressure steam of not greater than 6 bar rel, transferred from the ammonia section to the urea section, for use in at least one steam user in the urea section.
Singh is further deficient in the sense that it does not expressly teach recovery is performed at a single pressure level that is a low pressure.
Instead Singh teaches an integrated ammonia-urea process, steam production and use in the ammonia/syngas section, steam production and use in the urea section, heat transfer to the urea solution, CO2 stripping, low pressure recovery, and low pressure steam from ammonium carbamate recovery. (paragraphs 6, 24, 35, 44, 49-53, 59-60, 78, 96-97; figures 1-3; claims 3-4 and 17).
Finding of Prima Facie Obviousness Rationale and Motivation
(MPEP §2142-2143)
However, it would be prima facie obvious to one of ordinary skill in the art at the time of the invention, to use the steam generated in Singh’s ammonia/syngas section as available steam for the integrated ammonia-urea process, including by transferring steam from the ammonia section to the urea section, since Singh teaches an integrated ammonia-urea process and teaches steam production and steam use in the ammonia/syngas section and in the urea section.
Furthermore, it would be prima facie obvious to one of ordinary skill in the art at the time of the invention, to use steam at a lower pressure in Singh’s integrated ammonia-urea process, since Singh teaches that the pressure of the steam can vary and Singh teaches low pressure steam in the urea recovery section. Singh also recognizes that a large amount of energy in the form of heat, such as steam, and pressure, such as compressors, are required to operate the urea section, and other economically negative impacts are present. Since lowering the pressure of the steam would lower the energy needed, one would be motivated by economic concerns to lower the pressure of the steam.
Additionally, it would have been obvious to perform the CO2-stripping recovery at a single pressure level that is a low pressure, since Singh teaches CO2 stripping and teaches low pressure recovery. Selecting a single low pressure recovery level would have been a routine selection of a known recovery pressure arrangement in order to simplify operation and use low pressure recovery conditions already taught by Singh.
Additionally, to the extent the claimed pressure is “6 bar rel”, Singh’s 700 kPa steam pressure corresponds to about 7 bar absolute pressure, which is approximately 6 bar relative pressure. Thus, Singh teaches or at least renders obvious steam pressure close to or corresponding to the claimed low pressure value.
Additionally merely modifying process conditions such as the pressure is not a patentable modification, absent a showing of criticality. In re Aller, 220 F.2d 454, 105 U.S.P.Q. 233 (C.C.P.A. 1955). Generally, differences in process conditions will not support the patentability of subject matter encompassed by the prior art. Such formulations are result-effective variables which can be optimized. In re Boesch, 617 F.2d 272, 276, 205 USPQ 215, 219 (CCPA 1980), it was held that “discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art.” Further, in In re Aller, 220 F.2d454, 456, 105 USPQ 233,235 (CCPA 1955) the courts maintained that: “Where the general condition of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.”
Thus since pressure is a result-effective variable, it is the position of the examiner that one of ordinary skill in the art, at the time of the invention, would through routine and normal experimentation determine the appropriate steam pressure used in the integrated ammonia-urea plant.
Therefore, claims 37-38, and 39 are unpatentable over Singh.
Response to Arguments
Applicant’s arguments filed on 05/18/26 have been fully considered but are not persuasive for the following reasons:
Applicant argues that Singh does not teach or suggest “a low pressure steam at a pressure not greater than 6 bar rel, is transferred from the ammonia section to the urea section, for use in at least one steam user in the urea section.” Applicant further argues that Singh does not teach steam produced internally in both the ammonia section and the urea section for use in steam users of the plant.
These arguments are not persuasive. As set forth above, Singh teaches an integrated ammonia-urea process. Singh teaches steam and heat transfer in the integrated process, including steam used to heat the urea solution and to decompose ammonium carbamate. Singh also teaches steam production and use in the ammonia/syngas portion of the process and steam production and use in the urea portion of the process. Therefore, Singh does not merely teach two unrelated processes, but teaches an integrated ammonia-urea process in which steam and heat are used within the overall plant.
With regard to the pressure limitation, Singh teaches that steam pressure can vary and teaches low pressure steam in the urea recovery portion of the process. Singh also recognizes that a large amount of energy in the form of heat, such as steam, and pressure, such as compressors, are required to operate the urea section, and that other economically negative impacts are present. Thus, Singh recognizes that steam heat and pressure affect the energy and economic burden of the process.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to lower the pressure of the steam in Singh’s integrated ammonia-urea process in order to reduce the energy required and to reduce the economic negative impacts of the process. The reason to modify Singh does not come from applicant’s disclosure. Rather, the reason comes from Singh itself, which recognizes the problem of steam heat, pressure, energy use, and economic impact.
Applicant also argues that the Office has relied on impermissible hindsight because Singh allegedly uses medium pressure steam and not low pressure steam as claimed, is silent about integration of the steam systems of the ammonia section and the urea section, and does not teach that steam necessary for the ammonia section is produced within the same section.
This argument is not persuasive. The rejection is not based on impermissible hindsight. Singh teaches an integrated ammonia-urea process, steam production and use in the ammonia/syngas portion of the process, steam production and use in the urea portion of the process, low pressure steam in the urea recovery portion of the process, and the economic disadvantage of high energy use in the form of steam heat and pressure. Thus, Singh provides the reason to use available steam in the integrated process and to lower the pressure of the steam.
Furthermore, merely modifying process conditions such as pressure is not a patentable modification, absent a showing of criticality. Pressure is a result-effective variable because Singh recognizes that steam heat and pressure affect energy consumption and economic impact in the integrated ammonia-urea process. Applicant has not shown that the claimed pressure of not greater than 6 bar rel provides an unexpected result or is critical.
Applicant further argues that dependent claim 38 and new dependent claims 39 and 40 are patentable because they depend from allegedly patentable independent claim 37.
This argument is not persuasive. Claim 38 is unpatentable for the reasons set forth above with respect to claim 37 and for the additional reasons set forth in the rejection. Singh teaches self-stripping or ammonia-stripping and recovery performed at two pressure levels including a medium pressure and a low pressure. Singh also teaches CO2 stripping and low pressure recovery.
Claim 39 is unpatentable because Singh teaches or renders obvious a CO2-stripping process and recovery at a single pressure level that is a low pressure.
Claim 40 is unpatentable because Singh teaches or renders obvious recovery performed at two pressure levels including a medium pressure and a low pressure.
Accordingly, applicant’s arguments are not persuasive and the rejection of claims 37-40 under 35 U.S.C. 103 over Singh is maintained.
Conclusion
No claim is allowed.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Jennifer Cho Sawyer whose telephone number is (571) 270 1690. The examiner can normally be reached on Monday-Friday 9 AM - 6 PM PST.
If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Renee Claytor can be reached on (571) 272-8394. The fax phone number for the organization where this application or proceeding is assigned is 571-274-1690.
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Jennifer Cho Sawyer
Patent Examiner
Art Unit: 1691
/RENEE CLAYTOR/Supervisory Patent Examiner, Art Unit 1691
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