Patents by Inventor Ai-fu Chang

Ai-fu Chang 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).

  • Patent number: 9284430
    Abstract: A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.
    Type: Grant
    Filed: May 29, 2015
    Date of Patent: March 15, 2016
    Assignee: Chevron Phillips Chemical Company LP
    Inventors: Scott E. Kufeld, John D. Hottovy, Ai-fu Chang
  • Publication number: 20160030878
    Abstract: A process for component separation in a polymer production system, comprising (a) separating a polymerization product stream into a gas stream and a polymer stream, (b) contacting the polymer stream with a purge gas to yield a purged polymer and a spent purge gas comprising purge gas, ethylene, and ethane, (c) contacting the spent purge gas with a temperature swing adsorber contactor (TSAC) to yield a loaded TSAC, wherein at least a portion of the ethylene is adsorbed by the TSAC at a first temperature to yield TSAC-adsorbed ethylene, wherein a portion of the ethane is adsorbed by the TSAC at the first temperature to yield TSAC-adsorbed ethane, (d) heating the loaded TSAC to a second temperature to yield a regenerated TSAC, and (e) contacting the regenerated TSAC with a sweeping gas stream to yield a recovered adsorbed gas stream comprising sweeping gas, recovered ethylene and recovered ethane.
    Type: Application
    Filed: July 9, 2015
    Publication date: February 4, 2016
    Inventors: Lei JI, Ai-Fu CHANG
  • Publication number: 20160023966
    Abstract: A process for recovery of ethylene from a polymerization product stream of a polyethylene production system, comprising separating a light gas stream from the polymerization product stream, wherein the light gas stream comprises ethane and unreacted ethylene, contacting the light gas stream with an absorption solvent system, wherein the contacting the light gas stream with the absorption solvent system occurs at a temperature in a range of from about 40° F. to about 110° F., wherein at least a portion of the unreacted ethylene from the light gas stream is absorbed by the absorption solvent system, and recovering unreacted ethylene from the absorption solvent system to yield recovered ethylene.
    Type: Application
    Filed: October 7, 2015
    Publication date: January 28, 2016
    Inventors: John D. HOTTOVY, Ai-fu CHANG
  • Patent number: 9238193
    Abstract: Disclosed are systems and methods which provide a process stream comprising a gaseous component, capture the gaseous component from the process stream by an ionic liquid solvent of a separator, and recover a captured gaseous component from the ionic liquid solvent in a regenerator. A second gaseous component from the process stream may be captured by the ionic liquid solvent of the separator, and the second gaseous component may be recovered from the ionic liquid solvent in the regenerator. Alternatively, the second gaseous component from the process stream may be uncaptured by the ionic liquid solvent, and the uncaptured second gaseous component may be recovered from a membrane unit.
    Type: Grant
    Filed: July 23, 2013
    Date of Patent: January 19, 2016
    Assignees: CHEVRON PHILLIPS CHEMICAL COMPANY LP, CHEVRON U.S.A. INC.
    Inventors: Lei Ji, Ai-Fu Chang, Michael S. Driver, Hye-Kyung Timken
  • Patent number: 9227890
    Abstract: A process for component separation in a polymer production system comprising: (a) separating a polymerization product into a gas stream and a polymer stream; (b) processing the gas stream in distillation columns to yield a light hydrocarbon stream (LHS) comprising ethylene and ethane; (c) contacting LHS with a purged hydrocarbon adsorber to yield a loaded hydrocarbon adsorber and a non-adsorbed gas stream, wherein ethane is adsorbed by the purged hydrocarbon adsorber at a first pressure to yield adsorbed ethane, and wherein the non-adsorbed gas stream comprises recovered ethylene; (d) contacting the loaded hydrocarbon adsorber with a sweeping gas stream at a second pressure to yield an unloaded hydrocarbon adsorber and a recovered adsorbed gas stream comprising the sweeping gas stream and desorbed ethane; and (e) contacting the unloaded hydrocarbon adsorber with the sweeping gas stream at the first pressure to yield the purged hydrocarbon adsorber and a spent sweeping gas.
    Type: Grant
    Filed: July 20, 2015
    Date of Patent: January 5, 2016
    Assignee: Chevron Phillips Chemical Company LP
    Inventors: Lei Ji, Ai-Fu Chang
  • Patent number: 9187383
    Abstract: A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.
    Type: Grant
    Filed: April 30, 2015
    Date of Patent: November 17, 2015
    Assignee: CHEVRON PHILLIPS CHEMICAL COMPANY LP
    Inventors: Scott E. Kufeld, John D. Hottovy, Ai-fu Chang
  • Patent number: 9180405
    Abstract: A process for recovery of ethylene from a polymerization product stream of a polyethylene production system, comprising separating a light gas stream from the polymerization product stream, wherein the light gas stream comprises ethane and unreacted ethylene, contacting the light gas stream with an absorption solvent system, wherein the contacting the light gas stream with the absorption solvent system occurs at a temperature in a range of from about 40° F. to about 110° F., wherein at least a portion of the unreacted ethylene from the light gas stream is absorbed by the absorption solvent system, and recovering unreacted ethylene from the absorption solvent system to yield recovered ethylene.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: November 10, 2015
    Assignee: Chevron Phillips Chemical Company LP
    Inventors: John D. Hottovy, Ai-fu Chang
  • Publication number: 20150267027
    Abstract: A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.
    Type: Application
    Filed: May 29, 2015
    Publication date: September 24, 2015
    Inventors: Scott E. Kufeld, John D. Hottovy, Ai-fu Chang
  • Patent number: 9126878
    Abstract: A process for component separation in a polymer production system, comprising (a) separating a polymerization product stream into a gas stream and a polymer stream, (b) contacting the polymer stream with a purge gas to yield a purged polymer and a spent purge gas comprising purge gas, ethylene, and ethane, (c) contacting the spent purge gas with a temperature swing adsorber contactor (TSAC) to yield a loaded TSAC, wherein at least a portion of the ethylene is adsorbed by the TSAC at a first temperature to yield TSAC-adsorbed ethylene, wherein a portion of the ethane is adsorbed by the TSAC at the first temperature to yield TSAC-adsorbed ethane, (d) heating the loaded TSAC to a second temperature to yield a regenerated TSAC, and (e) contacting the regenerated TSAC with a sweeping gas stream to yield a recovered adsorbed gas stream comprising sweeping gas, recovered ethylene and recovered ethane.
    Type: Grant
    Filed: August 1, 2014
    Date of Patent: September 8, 2015
    Assignee: CHEVRON PHILLIPS CHEMICAL COMPANY LP
    Inventors: Lei Ji, Ai-Fu Chang
  • Publication number: 20150232396
    Abstract: A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.
    Type: Application
    Filed: April 30, 2015
    Publication date: August 20, 2015
    Inventors: Scott E. Kufeld, John D. Hottovy, Ai-fu Chang
  • Patent number: 9108147
    Abstract: A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: August 18, 2015
    Assignee: CHEVRON PHILLIPS CHEMICAL COMPANY LP
    Inventors: Scott E. Kufeld, John D. Hottovy, Ai-fu Chang
  • Patent number: 9108891
    Abstract: A process for component separation in a polymer production system comprising: (a) separating a polymerization product into a gas stream and a polymer stream; (b) processing the gas stream in distillation columns to yield a light hydrocarbon stream (LHS) comprising ethylene and ethane; (c) contacting LHS with a purged hydrocarbon adsorber to yield a loaded hydrocarbon adsorber and a non-adsorbed gas stream, wherein ethane is adsorbed by the purged hydrocarbon adsorber at a first pressure to yield adsorbed ethane, and wherein the non-adsorbed gas stream comprises recovered ethylene; (d) contacting the loaded hydrocarbon adsorber with a sweeping gas stream at a second pressure to yield an unloaded hydrocarbon adsorber and a recovered adsorbed gas stream comprising the sweeping gas stream and desorbed ethane; and (e) contacting the unloaded hydrocarbon adsorber with the sweeping gas stream at the first pressure to yield the purged hydrocarbon adsorber and a spent sweeping gas.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: August 18, 2015
    Assignee: Chevron Phillips Chemical Company
    Inventors: Lei Ji, Ai-Fu Chang
  • Publication number: 20150133711
    Abstract: Disclosed are systems and methods which provide a process stream comprising a gaseous component, capture the gaseous component from the process stream by an ionic liquid solvent of a separator, and recover a captured gaseous component from the ionic liquid solvent in a regenerator. A second gaseous component from the process stream may be captured by the ionic liquid solvent of the separator, and the second gaseous component may be recovered from the ionic liquid solvent in the regenerator. Alternatively, the second gaseous component from the process stream may be uncaptured by the ionic liquid solvent, and the uncaptured second gaseous component may be recovered from a membrane unit.
    Type: Application
    Filed: January 15, 2015
    Publication date: May 14, 2015
    Inventors: Lei JI, Ai-Fu CHANG, Michael Sean Driver, Hye-Kyung Cho Timken
  • Publication number: 20150030524
    Abstract: Disclosed are systems and methods which provide a process stream comprising a gaseous component, capture the gaseous component from the process stream by an ionic liquid solvent of a separator, and recover a captured gaseous component from the ionic liquid solvent in a regenerator. A second gaseous component from the process stream may be captured by the ionic liquid solvent of the separator, and the second gaseous component may be recovered from the ionic liquid solvent in the regenerator. Alternatively, the second gaseous component from the process stream may be uncaptured by the ionic liquid solvent, and the uncaptured second gaseous component may be recovered from a membrane unit.
    Type: Application
    Filed: July 23, 2013
    Publication date: January 29, 2015
    Inventors: Lei JI, Ai-Fu CHANG, Michael S. Driver, Hye-Kyung Timken
  • Publication number: 20120232231
    Abstract: A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.
    Type: Application
    Filed: April 13, 2012
    Publication date: September 13, 2012
    Applicant: CHEVRON PHILLIPS CHEMICAL COMPANY LP
    Inventors: Scott E. Kufeld, John D. Hottovy, Ai-fu Chang
  • Publication number: 20120232232
    Abstract: A process for recovery of ethylene from a polymerization product stream of a polyethylene production system, comprising separating a light gas stream from the polymerization product stream, wherein the light gas stream comprises ethane and unreacted ethylene, contacting the light gas stream with an absorption solvent system, wherein the contacting the light gas stream with the absorption solvent system occurs at a temperature in a range of from about 40° F. to about 110° F., wherein at least a portion of the unreacted ethylene from the light gas stream is absorbed by the absorption solvent system, and recovering unreacted ethylene from the absorption solvent system to yield recovered ethylene.
    Type: Application
    Filed: April 13, 2012
    Publication date: September 13, 2012
    Applicant: CHEVRON PHILLIPS CHEMICAL COMPANY LP
    Inventors: John D. Hottovy, Ai-fu Chang