Patents by Inventor Subhasis Bhattacharya

Subhasis Bhattacharya has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20240301300
    Abstract: A method of producing a base oil product by hydroprocessing unconverted oil from a hydrocracker in an unconverted oil upgrade reactor to produce upgraded unconverted oil and dewaxing the upgraded unconverted oil to produce the base oil product.
    Type: Application
    Filed: January 17, 2022
    Publication date: September 12, 2024
    Applicant: CHEVRON U.S.A. INC.
    Inventors: Viorel DUMA, Subhasis BHATTACHARYA, Guan-Dao LEI
  • Publication number: 20240076564
    Abstract: Described are processes to produce base oils with one more improved properties, e.g., lower aromatics, economically and/or efficiently. In some embodiments, the processes relate to two stage (or more) hydrofinishing which advantageously provides base oils with lower aromatics than comparable one stage processes.
    Type: Application
    Filed: January 18, 2022
    Publication date: March 7, 2024
    Applicant: CHEVRON U.S.A. INC.
    Inventors: Yihua ZHANG, Subhasis BHATTACHARYA, Guan-Dao LEI
  • Publication number: 20230348798
    Abstract: An improved process and catalyst system for making a base oil product and for improving base oil cloud point and pour point characteristics, while also providing good product yields. The process and catalyst system generally involves the use of a layered catalyst system comprising an SSZ-91 catalyst and an SSZ-32X catalyst arranged to sequentially contact a hydrocarbon feedstock with both catalysts and thereby provide dewaxed base oil products.
    Type: Application
    Filed: August 30, 2021
    Publication date: November 2, 2023
    Applicant: CHEVRON U.S.A. INC.
    Inventors: Subhasis BHATTACHARYA, Yihua ZHANG, Guan-Dao LEI, Ajit R. PRADHAN
  • Patent number: 9914887
    Abstract: The present invention is directed to a refining process for producing heavy lubricating base oils (LBO) from a blended hydrocarbonaceous feedstock containing a heavy coker gas oil, a visbroken gas oil, heavy cycle oil, oils from residue hydrocracking, aromatic extract or any other feedstock normally not conducive to lube oil basestock production, using a two-stage hydrocracking process.
    Type: Grant
    Filed: September 11, 2014
    Date of Patent: March 13, 2018
    Assignee: Chevron U.S.A. Inc.
    Inventor: Subhasis Bhattacharya
  • Patent number: 9803147
    Abstract: The present invention is directed to a refining process for producing hydroprocessed distillates and a heavy vacuum gas oil (HVGO). The process produces middle distillates that have reduced nitrogen and sulfur content, while simultaneously producing a 900° F.+ (482° C.+) HVGO stream useful as a fluidized catalytic cracking (FCC) unit feedstock.
    Type: Grant
    Filed: November 14, 2014
    Date of Patent: October 31, 2017
    Assignee: Chevron U.S.A. Inc.
    Inventors: Subhasis Bhattacharya, Ujjal Kumar Mukherjee, Marvin I. Greene
  • Patent number: 9796936
    Abstract: A process for heavy base oil production, comprising: a. performing an aromatic extraction of a first hydrocarbon feed to produce an aromatic extract, and a waxy raffinate; b. mixing the aromatic extract with a second hydrocarbon feed to make a mixed feed having greater than 2,000 wt ppm sulfur; c. feeding the mixed feed to a hydroprocessing unit to produce a heavy API Group II base oil having a kinematic viscosity at 70° C. from 22.6 to 100 mm2/s. An integrated refinery process unit for making heavy base oils, comprising: a. an aromatic extraction unit fluidly connected to a solvent dewaxing unit and a hydroprocessing unit; b. a first line from the aromatic extraction unit, that feeds an aromatic extract to a second hydrocarbon feed to make a mixed feed having greater than 2,000 wt ppm sulfur; and c. a connection that feeds the mixed feed to the hydroprocessing unit.
    Type: Grant
    Filed: September 9, 2015
    Date of Patent: October 24, 2017
    Assignee: Chevron U.S.A. Inc.
    Inventors: Guan-Dao Lei, Subhasis Bhattacharya, Axel Brait
  • Publication number: 20170066979
    Abstract: A process for heavy base oil production, comprising: a. performing an aromatic extraction of a first hydrocarbon feed to produce an aromatic extract, and a waxy raffinate; b. mixing the aromatic extract with a second hydrocarbon feed to make a mixed feed having greater than 2,000 wt ppm sulfur; c. feeding the mixed feed to a hydroprocessing unit to produce a heavy API Group II base oil having a kinematic viscosity at 70° C. from 22.6 to 100 mm2/s. An integrated refinery process unit for making heavy base oils, comprising: a. an aromatic extraction unit fluidly connected to a solvent dewaxing unit and a hydroprocessing unit; b. a first line from the aromatic extraction unit, that feeds an aromatic extract to a second hydrocarbon feed to make a mixed feed having greater than 2,000 wt ppm sulfur; and c. a connection that feeds the mixed feed to the hydroprocessing unit.
    Type: Application
    Filed: September 9, 2015
    Publication date: March 9, 2017
    Inventors: Guan-Dao Lei, Subhasis Bhattacharya, Axel Brait
  • Publication number: 20150136645
    Abstract: The present invention is directed to a refining process for producing hydroprocessed distillates and a heavy vacuum gas oil (HVGO). The process produces middle distillates that have reduced nitrogen and sulfur content, while simultaneously producing a 900° F.+ (482° C.+) HVGO stream useful as a fluidized catalytic cracking (FCC) unit feedstock.
    Type: Application
    Filed: November 14, 2014
    Publication date: May 21, 2015
    Applicant: Chevron U.S.A. Inc.
    Inventors: Subhasis Bhattacharya, Ujjal Kumar Mukherjee, Marvin I. Greene
  • Publication number: 20150068952
    Abstract: The present invention is directed to a refining process for producing heavy lubricating base oils (LBO) from a blended hydrocarbonaceous feedstock containing a heavy coker gas oil, a visbroken gas oil, heavy cycle oil, oils from residue hydrocracking, aromatic extract or any other feedstock normally not conducive to lube oil basestock production, using a two-stage hydrocracking process.
    Type: Application
    Filed: September 11, 2014
    Publication date: March 12, 2015
    Applicant: CHEVRON U.S.A. INC.
    Inventor: Subhasis Bhattacharya
  • Publication number: 20140371496
    Abstract: The present invention provides an improved method for solvent liquefaction of biomass to produce liquid products such as transportation fuel. The method uses a novel solvent combination that promotes liquefaction relatively quickly, and it reduces the need to transport large amounts of hydrogen or hydrogen-carrying solvents. It operates at lower pressure than previous methods, does not require a catalyst or hydrogen gas or CO input, and provides very high conversion of biomass into a bio-oil that can be further processed in a petroleum refinery. It also beneficially provides a way to recycle a portion of the crude liquefaction product for use as part of the solvent combination for the biomass liquefaction reaction.
    Type: Application
    Filed: September 4, 2014
    Publication date: December 18, 2014
    Applicant: CHEVRON U.S.A. INC.
    Inventors: James Floyd STEVENS, JR., Michelle K. YOUNG, Daniel D. EUHUS, Alexander Bruce COULTHARD, Douglas G. NAAE, Kerry Kennedy SPILKER, Jason Christopher HICKS, Subhasis BHATTACHARYA, Paul M. SPINDLER
  • Publication number: 20120005949
    Abstract: The present invention provides an improved method for solvent liquefaction of biomass to produce liquid products such as transportation fuel. The method uses a novel solvent combination that promotes liquefaction relatively quickly, and it reduces the need to transport large amounts of hydrogen or hydrogen-carrying solvents. It operates at lower pressure than previous methods, does not require a catalyst or hydrogen gas or CO input, and provides very high conversion of biomass into a bio-oil that can be further processed in a petroleum refinery. It also beneficially provides a way to recycle a portion of the crude liquefaction product for use as part of the solvent combination for the biomass liquefaction reaction.
    Type: Application
    Filed: April 4, 2011
    Publication date: January 12, 2012
    Inventors: James STEVENS, Michelle YOUNG, Daniel EUHUS, Alex COULTHARD, Doug NAAE, Kerry SPILKER, Jason HICKS, Subhasis BHATTACHARYA, Paul SPINDLER
  • Publication number: 20100200459
    Abstract: This invention is directed to a high conversion hydrocracking (HCR) unit to produce premium middle distillate fuel. Unconverted oil which is low in sulfur is fed to a Fluid Catalytic Cracking (FCC) unit. The process results in reduced hydrogen consumption and optimum reactor capacity. Feed is hydrotreated and separated into liquid and vapor streams. The vapor stream is passed to further processing and light ends recovery. The liquid stream is passed to a vacuum distillation column, where it is separated into at least three streams, the first stream comprising low boiling products and light ends, a second, higher boiling stream comprising the feed to a second hydroprocessing zone and third stream comprising unconverted oil. The second stream is passed to the second hydroprocessing zone, producing effluents which boil in the distillate range. The second hydroprocessing zone is generally a fuels hydrocracking unit.
    Type: Application
    Filed: February 10, 2009
    Publication date: August 12, 2010
    Inventor: Subhasis Bhattacharya
  • Publication number: 20090159493
    Abstract: This invention is directed to a process scheme in which a partial conversion hydrocracking (HCR) unit, preferably preceded by a hydrotreating unit, feeds unconverted oil to a FCC (fluid catalytic cracking ) unit. Most refineries run the FCC unit at the full capacity for optimal asset utilization. During shutdowns of Residue Desulfurization unit(s) which feed an FCC unit, it is desirable to reduce the conversion in the FCC feed hydrocracker. In this way, the feed to FCC unit is maximized. Jet and Diesel products that conform to specifications may be produced during low conversion HCR operation. Furthermore, undesirable over-saturation of the unconverted oil (UCO) from the HCR unit feeding the FCC unit can be avoided. Excess hydrogen consumption can also be avoided. Normally, further aromatic saturation of the middle distillate products from a low conversion HCR is achieved in a separate, post treatment, unit.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 25, 2009
    Inventor: Subhasis Bhattacharya