Prosecution Insights
Last updated: April 19, 2026
Application No. 18/263,888

Heat Recovery Apparatus for Cracked Gas and Heat Recovery Process for Cracked Gas

Non-Final OA §103§DP
Filed
Aug 01, 2023
Examiner
DOYLE, BRANDI M
Art Unit
1771
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Sinopec Engineering Incorporation
OA Round
1 (Non-Final)
63%
Grant Probability
Moderate
1-2
OA Rounds
3y 0m
To Grant
74%
With Interview

Examiner Intelligence

Grants 63% of resolved cases
63%
Career Allow Rate
299 granted / 477 resolved
-2.3% vs TC avg
Moderate +11% lift
Without
With
+11.0%
Interview Lift
resolved cases with interview
Typical timeline
3y 0m
Avg Prosecution
22 currently pending
Career history
499
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
58.5%
+18.5% vs TC avg
§102
5.5%
-34.5% vs TC avg
§112
22.3%
-17.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 477 resolved cases

Office Action

§103 §DP
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 . This communication is in response to the Election filed 10/22/2025. Claims 1-30 are pending. Election/Restrictions Applicant's election with traverse of group 1 in the reply filed on 10/22/2025 is acknowledged. The traversal is on the ground(s) that the special technical feature includes the quench configurations not taught in the art; and the two groups are closely related therefore there is no burden. This is not found persuasive because as one is directed to an apparatus and one a process having different classes and search terms and strategies. The requirement is still deemed proper and is therefore made FINAL. 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) 1-2, 5-7, 9-10 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 20210139620 in view of WO 2021016306. With respect to claims 1, 2, 5, US 20210139620 A1 teaches a steam cracking and separation apparatus comprising a liquid pyrolysis reactor and gas pyrolysis reactor; a heat recovery device for liquid feedstock cracked gas (E-3) for cooling a liquid hydrocracked gaseous effluent; and a heat recovery device for gaseous feedstock cracked gas (E-1) for cooling a gaseous hydrocracked gaseous effluent. The cooled effluents are quenched 1060a 1060b. The cooled and quenched effluent is passed to downstream separation (Figure). PNG media_image1.png 498 782 media_image1.png Greyscale a US 20210139620 Figure 12 US 20210139620 is silent regarding the specific downstream separation apparatus. PNG media_image2.png 393 643 media_image2.png Greyscale b WO 2021016306 WO 2021016306 teaches an apparatus comprising a steam cracking reactor and quench; the cooled effluent 115 is passed through a first separator 117 for removing heavy fraction; the effluent 119 is then passed to the second heavy fraction removal unit 130. The second unit includes a bottom discharge pipeline for quench oil, it is known to utilize a pump on discharge streams, and a quench oil heat recovery device 144 (Figure). The discharge pipeline is divided into more than two branches, wherein the first branch is connected to the second part of the heavy component removal unit 166, and the second branch “can be recycled via lines 146 and 113 as the quench fluid” (0033). It would have been obvious to one of ordinary skill in the art at the time of filing to utilize the system for fractionating a pyrolysis effluent of WO 2021016306 as the downstream separation means in the apparatus of US 20210139620. With respect to claim 2, WO 2021016306 teaches a heavy component removal unit comprising a tar removal column 117 and distillate fractionating column 130; 117 is configured with a discharge pipeline at the top and a discharge pipeline for liquid-solid heavy component fuel oil at the bottom; 117 is connected to 130 via discharge at the top; the discharge pipeline for quench oil is configured at the bottom of the second column 130; and a discharge pipeline for gas phase is configured at the top of column 130 (Figure). With respect to claim 5, WO 2021016306 includes a third water quench column 150 with 180 connected via the overhead discharge of second column 130 (Figure). The quench water column 150 contains a discharge pipeline at the column top and an extraction pipeline at the bottom capable of recovering heavy oil and gasoline. With respect to claim 6, WO 2021016306 teaches the extraction pipeline returns to column 130 and is passed to stripper 186. Column 150/180 is configured with a discharge pipeline for process water 182 and quench water 183. (Figure 1) With respect to claim 7, the art is silent wherein the discharge pipeline of the heat recovery device for gaseous feedstock cracked gas (E-1) is connected to the gasoline fractionating column (E-12). However, it would have been with in the skill of one in the art at the time of filing to pass the combined effluents or individual effluents to the two separation towers. Where the effluents were passed separate, the gas cracked effluent could passed to the tar separator 117 or bypass and be passed directly to the column 130. With respect to claim 9, US 20210139620 and WO 2021016306 both show the quench is at the discharge of the heat recovery device (figure). With respect to claim 10, WO 2021016306 teaches the second branch is connected to the upper part of the heavy component removal column 130; the discharge pipeline of the heat recovery device for liquid feedstock cracked gas is connected to the lower part of the heavy component removal column 117. With respect to claim 12, WO 2021016306 teaches coke removal drum (0027). Claim(s) 1, 3-4, 8-9, and 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 20210139620 in view of US 3923921. With respect to claim 1, US 20210139620 A1 teaches a steam cracking and separation apparatus comprising a liquid pyrolysis reactor and gas pyrolysis reactor; a heat recovery device for liquid feedstock cracked gas (E-3) for cooling a liquid hydrocracked gaseous effluent; and a heat recovery device for gaseous feedstock cracked gas (E-1) for cooling a gaseous hydrocracked gaseous effluent. The cooled effluents are quenched 1060a 1060b. The cooled and quenched effluent is passed to downstream separation (Figure). PNG media_image1.png 498 782 media_image1.png Greyscale c US 20210139620 Figure 12 US 20210139620 is silent regarding the specific downstream separation apparatus. US 3923921 teaches a heavy component removal unit connected to the discharge of the heat exchanger. The heavy component removal comprises a part 17 for removing tar and a upper part for removing intermediate components; upper portion of the column is the second part and includes a quench pump 9, the quench oil heat recovery device 12, and then divided into two branches, wherein the first branch 16 is connected to the second part of the heavy component removal unit, and the second branch 14 is connected to the discharge pipeline. See Figure and col. 3. It would have been obvious to one of ordinary skill in the art at the time of the invention to utilize the wash tower of US 3923921 as the downstream apparatus for separation of the cracked effluent in US 20210139620. PNG media_image3.png 356 567 media_image3.png Greyscale d US 3923921 Figure 1 With respect to claim 3, US 3923921 teaches a single vessel with a lower part for heavy oil removal and a second, upper part for distillate removal and quench. With respect to claim 4, US 3923921 shows a bottom heavy removal flash system for separating tar and heavy components (Figure 1; Col. 3, lines 58+). With respect to claim 8, the art is silent regarding how the effluents are passed to the downstream separation columns. However, it would have been with in the skill of one in the art to pass the combined effluents or individual effluents to the two separation towers. Where the effluents were passed separately, it would have been obvious to one of ordinary skill at the time of filing to pass the effluent the lower section with the heavy effluent or the upper section of the fractionating column, as one of a limited number of choices. With respect to claim 9, US 20210139620 and US 3923921 both show the quench is at the discharge of the heat recovery device (figure). With respect to claim 11, US 3923921 teaches the second branch is connected to the upper second of the fractionation column and the cooled effluent to the lower section of the fractionation column (Figure). However, the exact location will depend on the specific operation parameters and design of the column. It would have been obvious to one of ordinary skill in the art at the time of filing to select the quench return location and feed location to achieve the desired cooling and separation. Claim(s) 27-28 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 20210139620 in view of US 3923921 as applied to claims 1, 3-4, 8-9, and 11, further in view of WO 2021016306. With respect to claim 27, US 3923921 teaches a gaseous stream pipeline discharged from the top of the quenched tower, connected to a settling drum for separation and discharge of water, condensed oil, and uncondensed gaseous hydrocarbon products. The art fails to teach a quench column connected to the gaseous discharge. WO 2021016306 includes a two column quench oil system with an overhead gaseous discharge as discussed above; and further teaches a third water quench column 150 with 180 connected via the overhead discharge of second column 130 (Figure). “The overhead product via line 143 can be introduced into a quench tower 150 along with quench water, e.g., a recycled quench water, via line 183 to cool the overhead product. A process gas that can include ethylene can be recovered via line 151 and a mixture that includes steam cracker naphtha and quench water via line 152 can be conducted away from the quench tower 150. It should be understood that, while shown as being separate vessels, the quench tower 150 can be integrated with the primary fractionator 130.” The quench water column 150 contains a discharge pipeline at the column top and an extraction pipeline at the bottom capable of recovering heavy oil and gasoline. The extraction pipeline returns to column 130 and is passed to stripper 186. Column 150/180 is configured with a discharge pipeline for process water 182 and quench water 183. (Figure 1) It would have been obvious to one of ordinary sill in the art at the time of filing to include a quench water tower in the process of US 20210139620 in view of US 3923921 to further cool the overhead effluent and separate the product fractions. Double Patenting Any inquiry concerning this communication or earlier communications from the examiner should be directed to Brandi Doyle whose telephone number is (571)270-1141. The examiner can normally be reached Monday-Friday, 8:00 AM - 3:00 PM. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Prem Singh can be reached at (571)272-6381. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /BRANDI M DOYLE/Examiner, Art Unit 1771 /PREM C SINGH/Supervisory Patent Examiner, Art Unit 1771
Read full office action

Prosecution Timeline

Aug 01, 2023
Application Filed
Jan 10, 2026
Non-Final Rejection — §103, §DP (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12590254
METHOD FOR HYDRODESULFURISATION OF A PETROLEUM FRACTION USING A CATALYST CONTAINING A GRAPHITIC MATERIAL CHARACTERISED BY THE H/C RATIO THEREOF
2y 5m to grant Granted Mar 31, 2026
Patent 12583746
Hydrogen Production Process and Plant
2y 5m to grant Granted Mar 24, 2026
Patent 12576382
CERAMIC COATING ON METAL PARTS TO REDUCE DEPOSIT OF METALLIC TRANSITION METALS IN HYDROGENATION REACTIONS
2y 5m to grant Granted Mar 17, 2026
Patent 12551867
LOW IRON, LOW Z/M FLUID CATALYTIC CRACKING CATALYST
2y 5m to grant Granted Feb 17, 2026
Patent 12544690
AUTOMATIC SEPARATION APPARATUS FOR FOUR FRACTIONS OF HEAVY OIL AND SEPARATION METHOD THEREOF
2y 5m to grant Granted Feb 10, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

1-2
Expected OA Rounds
63%
Grant Probability
74%
With Interview (+11.0%)
3y 0m
Median Time to Grant
Low
PTA Risk
Based on 477 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month