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 response to the non-final Office action in a reply filed 03/11/2026 is acknowledged. Amendment to claims 1-4, 8, 10, 12-16 and addition of new claims 18-23 is noted.
Objection to claims 1, 4, 5, 10, 12 and 16 in view of claim amendments is withdrawn.
Rejection of claim 3 under 35 USC 112 in view of claim amendment is withdrawn.
Response to Arguments
Applicant's arguments filed 03/11/2026 have been fully considered but they are not persuasive.
I. Absent of a Hydrogen Purification Unit
Applicant argues, “Jensen's NWU is a cryogenic separation technology integral to Jensen's ammonia plant. In contrast, pending claim 1 expressly excludes "a cryogenic separation unit." The fact that Jensen's cryogenic section is configured for ammonia loop make-up purification does not negate that it is a cryogenic separation unit present in the plant. The claims recite absence of such units; Jensen requires one.
Further, there is no reason one skilled in the art would eliminate the NWU from Jensen, as doing such would defeat the very purpose of Jensen's process (producing an "inert free" ammonia synthesis make-up gas) and change the principle of operation of Jensen. See, e.g., Jensen, 11[0065]-[0066].
Applicant’s argument is not persuasive. It is to be noted that claimed invention is drawn to “a process and plant for producing a hydrogen-rich stream from a hydrocarbon feed”. Jensen’s invention is drawn to an “ATR based ammonia process and plant”. This clearly indicates that Jensen produces pure hydrogen and nitrogen and proceeds further to produce ammonia. The claim clearly says,”wherein said plant is absent of a hydrogen purification unit including a pressure swing adsorption (PSA) unit , a hydrogen membrane and a cryogenic separation unit” (Emphasis added). Obviously, claim(s) exclude a hydrogen purification unit. Jensen’s purpose of nitrogen wash unit (NWU) is to remove CH4, Ar, He and CO from syngas (Paragraph 0062). It has nothing to do with hydrogen purification.
It is also to be noted that the claimed invention has an ATR (110) with an oxygen supply (15) obtained from an air separation unit (145) (Applicant’s Fig. 1; Specification page 17, lines 4-7; page 22, lines 27-28). Jensen et al, on the other hand, also use an air separation unit, separating air into oxygen and nitrogen (Fig. 1 and 2; Paragraph 0059). Thus, the Applicant uses oxygen obtained from air separation unit (ASU) in the ATR and is silent about nitrogen separated from air. On the other hand, Jensen et al use oxygen from ASU in the ATR, and further disclose use of nitrogen in the wash unit and ammonia synthesis (Paragraph 0059).
II. CO2-Removal Section that is an Amine Wash Unit
The Applicant argues, “Licht's process produces its "hydrogen-containing product gas" only after a hydrogen purification step (e.g., a PSA/TSA, forbidden by the present claims), following scrubbing. Licht, 11043], [0047].
Thus, even if one were to import amine chemistry from Licht into Jensen's generic "CO2 wash," Licht still relies on PSA/TSA to obtain the hydrogen-containing product gas. The asserted combination therefore cannot yield the claimed arrangement in which the amine wash unit itself (with HP/LP flash drums) provides the H₂-rich stream that is then used as fuel, while the overall plant remains free of PSA/membrane/cryogenic hydrogen purification units”.
The Applicant’s argument is not persuasive. Jensen et al use water wash and molecular sieve to remove CO2 (Paragraph 0027, 0028, 0054, 0055, 0061). Licht et al used as an evidentiary reference, disclose carbon dioxide removal by any scrubbing fluid known in the art, including amine solution (Paragraph 0043). Thus, Licht et al reliance on PSA/TSA to obtain the hydrogen-containing product gas should not affect Jensen et al invention.
III. Feeding Hydrogen-rich Stream as Fuel to Fired Heaters
The Applicant argues, “Jensen does not teach using an H₂-rich stream (produced by a CO₂ removal section) as fuel for fired heaters. Rather, Jensen's fired heater fuel is a mixture that includes natural gas, nitrogen-wash waste gas, off-gas, and "flash gas (from the CO2 removal section)." Jensen, ||[0045].
Licht teaches combusting "a portion of the hydrogen-containing product gas" as fuel, but only after generating that product gas via a hydrogen purification unit (PSA/TSA), which the claims exclude. See Licht, [0054].
Thus, neither reference teaches using the specific H₂-rich stream produced by CO₂- removal section is an amine wash unit (with HP/LP flash drums) as the fired-heater fuel in a plant that is free of a hydrogen purification unit (including PSA/membrane/cryogenic hydrogen purification units). Adopting Licht's "use H2 product as fuel" would require adding a PSA (contrary to the claims) or fundamentally reconfiguring Jensen's ammonia plant and changing its principle of operation by removing the NWU”. Emphasis Added.
Applicant’s argument is not persuasive because Jensen et al teach the flash gas from CO2 removal section recycled to the fired heater comprises 75% hydrogen (Paragraph 0067; Page 4, Table 2). Clearly, this stream is a H2-rich stream as claimed. Also, as discussed earlier, Licht’s use of H2 product as fuel has no bearing on Jensen’s invention, because Licht is simply an evidentiary reference.
Rejection of previously presented claims 1-17 and newly added claims 18-23 follows.
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 (i.e., changing from AIA to pre-AIA ) 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, 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.
Claim(s) 1-23 are rejected under 35 U.S.C. 103 as being unpatentable over Jensen et al (US 2019/0039886 A1) evidenced by Licht et al (US 2010/0310949 A1) and Grotz, Jr. (US 3,549,335).
With respect claims 1, 13, 14, 22 and 23, Jensen et al disclose a plant and process for producing H2-rich stream (ultimately to be used in ammonia synthesis) from a hydrocarbon feed (Fig. 1, Claims 1, 17).
Jensen et al disclose an autothermal reformer {ATR} (Fig 1, and 0031), receiving a hydrocarbon feed (Fig. 1, 0010) and converting it to syngas (0010).
Jensen et al, use an air separation unit, separating air into oxygen and nitrogen (Fig. 1 and 2; Paragraph 0059). Oxygen from ASU is used in the ATR, and nitrogen is used in the wash unit and ammonia synthesis (Paragraph 0059).
Jensen et al also disclose a shift section, comprising one or more water gas shift units (Fig. 1; 0046) and converting the syn gas to shifted gases (Fig. 1; 0012, 0013, 0014, 0046, 0047).
Jensen et al further disclose (Fig. 1; 0054, 0083) a CO2 removal section, separating a CO2 rich stream (Fig. 1; 0054, 0061, 0083), a H2-rich stream (Table 2) and also a high-pressure flash gas stream (Fig. 1; 0045).
Jensen et al also disclose a fired heater with the recycled fuel comprising natural gas, waste gas and flash gas (Fig. 1; 0045, 0063). The fired heater is used to preheat the hydrocarbon feed before entering the ATR (Fig. 1; 0045). It is to be noted that the recycle stream from the nitrogen wash unit (NWU) and going to the fired heater is a hydrogen -rich stream (Table 2). This is evidenced by Licht et al.
Licht et al disclose in a process similar to Jensen et al, combusting a fuel gas comprising a portion of the hydrogen-containing product gas in the reformer furnace external to the plurality of catalyst-containing reformer tubes (Figures 1, 2; 0012).
Jensen et al plant and process do not use any hydrogen purification unit such as a pressure swing adsorption (PSA) unit, a hydrogen membrane or a cryogenic separation unit.
Jensen et al plant uses a CO2-removal section and regeneration of CO₂ wash (Fig. 1; 0054, 0055, 0061). Al though Jensen et al disclose a typical CO2 removal step using water wash and by adsorption, it is within the skilled art to use an amine solution, as evidenced by Licht et al.
Licht et al disclose CO2 removal by any standard method including an amine wash (0043). Licht further disclose separation and recovery of CO₂ by suitable devices (0047). As also disclosed by Jensen et al, regeneration of CO2 wash solution will require a stripper and flash drum as claimed.
As mentioned earlier, Jensen et al disclose recycling of high-pressure flash gas (0045) and H2-rich stream-(Fig. 1) to the fired heater.
With respect to claims 2, 3, 4 and 15, all the limitations of claims 1 and 13 have already been discussed.
Jensen et al disclose recycle of fuel gas comprising 92.96% H2 to the fired heater (Fig. 1, 2; Table 2).
Licht et al also disclose that the fuel gas may comprise 30 to 98 volume % hydrogen- containing product gas and 2 to 70 volume% of by-product gas (0024).
In addition, Jensen et al disclose, "It is well known that MT/LT shift catalysts are prone to produce methanol as byproduct. Such byproduct formation can be reduced by increasing steam/carbon" (0054). This indicates that one with ordinary skill in the art will recycle flash gas stream to the CO2 absorber of the amine wash to increase steam/carbon ratio.
With respect to claims 5 and 19-21, Jensen et al disclose that process gas enters the ATR at 650°C (0072). It is to be noted that the temperature of the hydrocarbon gas to ATR may be different. This is evidenced by Grotz.
Grotz discloses a process and plant using autothermal reactor similar to Jensen et al (Fig. 1, 2, 3, 4). Grotz also discloses that the steam-hydrocarbon feed mixture is preheated to 890°F (477°C) before entering the reformer catalyst tubes (Column 8, lines 46-50). This indicates that inlet temperature to the ATR can vary as claimed.
With respect to claims 6, 7,16 and 17, Jensen et al disclose steam-to-carbon ratio of 2.6-0.1 in the ATR and pressure at 39.3 kg/cm² (39.0 barg) (0039; Table 1).
With respect to claim 8, Jensen et al disclose WGS comprising High Temperature, Medium Temperature and Low Temperature shifts (Claims 8, 9, 10).
With respect to claim 9, Jensen et al disclose steam superheater being heated by flash gas from CO2 removal section (0045).
With respect to claims 10, 11 and 18, Jensen et al disclose a pre-reformer upstream of ATR, which may be optional (0044). Jensen et al also disclose a fixed bed reforming unit (Paragraph 0037). The details of the reformer are well known to those skilled in the art as evidenced by Grotz (See Fig. 1and 4; Abstract; Column 10, lines 11-46).
With respect to claim 12, Jensen et al disclose that pre-reformer may provide an efficient sulfur guard resulting in a practically sulfur-free feed gas entering the ATR and the downstream system (0044). Mixing of hydrogen-rich stream and hydrocarbon feed before entering the ATR has already been discussed.
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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/PREM C SINGH/Supervisory Patent Examiner, Art Unit 1771
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