Patents by Inventor Mark Julian Roberts
Mark Julian Roberts 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: 10982898Abstract: Described herein are methods and systems for the liquefaction of natural gas to produce a LNG product. The methods and systems use an apparatus for separating a flash gas from a liquefied natural gas (LNG) stream to produce a LNG product and recovering refrigeration from the flash gas. The apparatus includes a shell casing enclosing a heat exchange zone comprising a coil wound heat exchanger, and a separation zone. The heat exchange zone is located above and in fluid communication with the separation zone. Flash gas is separated from the LNG product in the separation zone and flows upwards from the separation zone into the heat exchange zone where refrigeration is recovered from the separated flash gas.Type: GrantFiled: May 11, 2018Date of Patent: April 20, 2021Assignee: Air Products and Chemicals, Inc.Inventors: Fei Chen, Christopher Michael Ott, Annemarie Ott Weist, Mark Julian Roberts
-
Patent number: 10866022Abstract: Described herein are methods and systems for the liquefaction of a natural gas stream using a refrigerant comprising methane or a mixture of methane and nitrogen. The methods and systems use a refrigeration circuit and cycle that employs one or more turbo-expanders to expand one or more streams of gaseous refrigerant to provide one or more streams of at least predominantly gaseous refrigerant that are used to provide refrigeration for liquefying and/or precooling the natural gas, and a J-T valve to expand down to a lower pressure a stream of liquid or two-phase refrigerant to provide a vaporizing stream of refrigerant that provides refrigeration for sub-cooling.Type: GrantFiled: April 27, 2018Date of Patent: December 15, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts
-
Patent number: 10852059Abstract: Systems and methods described for increasing capacity and efficiency of natural gas liquefaction processes having a mixed refrigerant precooling system with multiple pressure levels comprising cooling the compressed mixed refrigerant stream and separating the cooled compressed mixed refrigerant stream into a vapor and liquid portion. The liquid portion provides refrigeration duty to a first precooling heat exchanger. The vapor portion is further compressed, cooled, and condensed, and used to provide refrigeration duty to a second precooling heat exchanger. A flash gas separated from the liquefied natural gas is warmed and combined with the natural gas feed stream.Type: GrantFiled: September 28, 2017Date of Patent: December 1, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts, Adam Adrian Brostow
-
Patent number: 10788260Abstract: Described herein is a method of removing refrigerant from a natural gas liquefaction system in which vaporized mixed refrigerant is withdrawn from the closed-loop refrigeration circuit and introduced into a distillation column so as to be separated into an overhead vapor enriched in methane and a bottoms liquid enriched in heavier components. Overhead vapor is withdrawn from the distillation column to form a methane enriched stream that is removed from the liquefaction system, and bottoms liquid is reintroduced from the distillation column into the closed-loop refrigeration circuit. Also described are methods of altering the rate of production in a natural gas liquefaction system in which refrigerant is removed as described above, and a natural gas liquefaction systems in which such methods can be carried out.Type: GrantFiled: August 8, 2017Date of Patent: September 29, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Brian Keith Johnston, Gowri Krishnamurthy, Mark Julian Roberts
-
Patent number: 10788261Abstract: Described herein are methods and systems for the liquefaction of a natural gas feed stream using a refrigerant comprising methane. The methods and systems use a refrigeration circuit and cycle that employs two or more turbo-expanders to expand two or more streams of gaseous refrigerant down to different pressures to provide cold streams of at least predominantly gaseous refrigerant at different pressures that are used to provide refrigeration for precooling and liquefying the natural gas. The resulting liquefied natural gas stream is then flashed to produce an LNG product and a flash gas, the flash gas being recycled to the natural gas feed stream.Type: GrantFiled: April 27, 2018Date of Patent: September 29, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts
-
Patent number: 10767922Abstract: A method and apparatus for liquefying a natural gas feed stream and removing nitrogen therefrom to produce a nitrogen-depleted LNG product, in which a natural gas feed stream is fed into the warm end of a main heat exchanger, cooled and at least partially liquefied, withdrawn from an intermediate location of the main heat exchanger and separated to form a nitrogen-enriched natural gas vapor stream and a nitrogen-depleted natural gas liquid stream, the liquid and vapor streams being reintroduced into an intermediate location of the main heat exchanger and further cooled in parallel to form a first LNG stream and a first at least partially liquefied nitrogen-enriched natural gas stream, respectively.Type: GrantFiled: June 19, 2017Date of Patent: September 8, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Fei Chen, Yang Liu, Gowri Krishnamurthy, Christopher Michael Ott, Mark Julian Roberts
-
Patent number: 10753676Abstract: Systems and methods described for increasing capacity and efficiency of natural gas liquefaction processes having a mixed refrigerant precooling system with multiple pressure levels comprising cooling the compressed mixed refrigerant stream and separating the cooled compressed mixed refrigerant stream into a vapor and liquid portion. The liquid portion provides refrigeration duty to a first precooling heat exchanger. The vapor portion is further compressed, cooled, and condensed, and used to provide refrigeration duty to a second precooling heat exchanger. A flash gas separated from the liquefied natural gas is warmed and combined with the natural gas feed stream.Type: GrantFiled: September 28, 2017Date of Patent: August 25, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts, Adam Adrian Brostow
-
Publication number: 20200217585Abstract: A system and method for increasing the efficiency of natural gas liquefaction processes by using a hybrid cooling system and method. More specifically, a system and method for converting a transcritical precooling refrigeration process to a subcritical process. In one embodiment, the refrigerant is cooled to sub-critical temperature using an economizer. In another embodiment, the refrigerant is cooled to a sub-critical temperature using an auxiliary heat exchanger. Optionally, the economizer or auxiliary heat exchanger can be bypassed when ambient temperatures are sufficiently low to cool the refrigerant to a sub-critical temperature. In another embodiment, the refrigerant is isentropically expanded.Type: ApplicationFiled: March 23, 2020Publication date: July 9, 2020Applicant: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts
-
Publication number: 20200200471Abstract: A liquefaction system is capable of sequentially or simultaneously liquefying multiple feed streams of hydrocarbons having different normal bubble points with minimal flash. The liquefying heat exchanger has separate circuits for handling multiple feed streams. The feed stream with the lowest normal boiling point is sub-cooled sufficiently to suppress most of the flash. Feed streams with relatively high normal boiling points are cooled to substantially the same temperature, then blended with bypass streams to maintain each product near its normal bubble point. The system can also liquefy one stream at a time by using a dedicated circuit or by allocating the same feed to multiple circuits.Type: ApplicationFiled: March 2, 2020Publication date: June 25, 2020Applicant: Air Products and Chemicals, Inc.Inventors: Laurent Marc Brussol, David Joseph Holzer, Sylvain Vovard, Russell Shnitser, Adam Adrian Brostow, Mark Julian Roberts
-
Patent number: 10663220Abstract: Systems and methods described for increasing capacity and efficiency of natural gas liquefaction processes having a mixed refrigerant precooling system with multiple pressure levels comprising cooling the compressed mixed refrigerant stream and separating the cooled compressed mixed refrigerant stream into a vapor and liquid portion. The liquid portion provides refrigeration duty to a first precooling heat exchanger. The vapor portion is further compressed, cooled, and condensed, and used to provide refrigeration duty to a second precooling heat exchanger. Optionally additional precooling heat exchangers, and/or phase separators may be used.Type: GrantFiled: October 7, 2016Date of Patent: May 26, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts
-
Patent number: 10619917Abstract: A liquefaction system is capable of sequentially or simultaneously liquefying multiple feed streams of hydrocarbons having different normal bubble points with minimal flash. The liquefying heat exchanger has separate circuits for handling multiple feed streams. The feed stream with the lowest normal boiling point is sub-cooled sufficiently to suppress most of the flash. Feed streams with relatively high normal boiling points are cooled to substantially the same temperature, then blended with bypass streams to maintain each product near its normal bubble point. The system can also liquefy one stream at a time by using a dedicated circuit or by allocating the same feed to multiple circuits.Type: GrantFiled: September 13, 2017Date of Patent: April 14, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Laurent Marc Brussol, David Joseph Holzer, Sylvain Vovard, Russell Shnitser, Adam Adrian Brostow, Mark Julian Roberts
-
Publication number: 20200056836Abstract: A natural gas liquefaction method and system having integrated nitrogen removal. Recycled LNG gas is cooled in a separate and parallel circuit from the natural gas stream in the main heat exchanger. Cooled recycled gas and natural gas streams are directed to a nitrogen rectifier column after the warm bundle. The recycle stream is introduced to the rectifier column above the natural gas stream and at least one separation stage is located in the rectifier column between the recycle stream inlet and the natural gas inlet. The bottom stream from the rectifier column is directed to a cold bundle of the main heat exchanger where it is subcooled.Type: ApplicationFiled: August 14, 2018Publication date: February 20, 2020Applicant: Air Products and Chemicals, Inc.Inventors: Mark Julian Roberts, Fei Chen, Christopher Michael Ott, Annemarie Ott Weist
-
Patent number: 10544986Abstract: A system and method is provided for increasing the capacity and efficiency of natural gas liquefaction processes by debottlenecking the refrigerant compression system. A secondary compression circuit comprising at least one double flow compressor is provided in parallel fluid flow communication with at least a portion of a primary compression circuit.Type: GrantFiled: March 29, 2017Date of Patent: January 28, 2020Assignee: Air Products and Chemicals, Inc.Inventors: Joseph Gerard Wehrman, Gowri Krishnamurthy, Mark Julian Roberts
-
Publication number: 20190346203Abstract: Described herein are methods and systems for the liquefaction of natural gas to produce a LNG product. The methods and systems use an apparatus for separating a flash gas from a liquefied natural gas (LNG) stream to produce a LNG product and recovering refrigeration from the flash gas. The apparatus includes a shell casing enclosing a heat exchange zone comprising a coil wound heat exchanger, and a separation zone. The heat exchange zone is located above and in fluid communication with the separation zone. Flash gas is separated from the LNG product in the separation zone and flows upwards from the separation zone into the heat exchange zone where refrigeration is recovered from the separated flash gas.Type: ApplicationFiled: May 11, 2018Publication date: November 14, 2019Applicant: Air Products and Chemicals, Inc.Inventors: Fei Chen, Christopher Michael Ott, Annemarie Ott Weist, Mark Julian Roberts
-
Publication number: 20190331413Abstract: Described herein are methods and systems for the liquefaction of a natural gas stream using a refrigerant comprising methane or a mixture of methane and nitrogen. The methods and systems use a refrigeration circuit and cycle that employs one or more turbo-expanders to expand one or more streams of gaseous refrigerant to provide one or more streams of at least predominantly gaseous refrigerant that are used to provide refrigeration for liquefying and/or precooling the natural gas, and a J-T valve to expand down to a lower pressure a stream of liquid or two-phase refrigerant to provide a vaporizing stream of refrigerant that provides refrigeration for sub-cooling.Type: ApplicationFiled: April 27, 2018Publication date: October 31, 2019Applicant: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts
-
Publication number: 20190331414Abstract: Described herein are methods and systems for the liquefaction of a natural gas feed stream using a refrigerant comprising methane. The methods and systems use a refrigeration circuit and cycle that employs two or more turbo-expanders to expand two or more streams of gaseous refrigerant down to different pressures to provide cold streams of at least predominantly gaseous refrigerant at different pressures that are used to provide refrigeration for precooling and liquefying the natural gas. The resulting liquefied natural gas stream is then flashed to produce an LNG product and a flash gas, the flash gas being recycled to the natural gas feed stream.Type: ApplicationFiled: April 27, 2018Publication date: October 31, 2019Applicant: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts
-
Patent number: 10393429Abstract: A method for controlling the flow of natural gas and refrigerant in the main heat exchanger of a natural gas liquefaction facility. The method provides for the automated control of a flow rate of a natural gas feed stream through a heat exchanger based on one or more process variables and set points. The flow rate of refrigerant streams through the heat exchanger is controlled by different process variables and set points, and is controlled independently of the flow rate of the natural gas feed stream.Type: GrantFiled: April 6, 2016Date of Patent: August 27, 2019Assignee: Air Products and Chemicals, Inc.Inventors: Fei Chen, Brian Keith Johnston, Mark Julian Roberts
-
Patent number: 10359228Abstract: A system and method for liquefaction of a natural gas stream utilizing a plurality of asymmetric parallel pre-cooling circuits. The use of asymmetric parallel cooling circuits allows for greater control over each refrigerant stream during the cooling process and simplifies process control by dedicating heat exchangers to performing similar duties.Type: GrantFiled: May 20, 2016Date of Patent: July 23, 2019Assignee: Air Products and Chemicals, Inc.Inventors: Adam Adrian Brostow, Fei Chen, Mark Julian Roberts, Christopher Michael Ott
-
Patent number: 10323880Abstract: The present invention relates to methods of increasing the operability, capacity, and efficiency of natural gas liquefaction processes, with a focus on mixed refrigerant cycles. The present invention also relates to natural gas liquefaction systems in which the above-mentioned methods can be carried out. More specifically, a refrigerant used in a pre-cooling heat exchanger of a natural gas liquefaction plant is withdrawn from the pre-cooling heat exchanger, separated into liquid and vapor streams in a liquid-vapor separator after being cooled and compressed. The vapor portion is further compressed, cooled, and fully condensed, then returned to the liquid-vapor separator. Optionally, the fully condensed stream may be circulated through a heat exchanger before being returned to the liquid-vapor separator for the purpose of cooling other streams, including the liquid stream from the liquid-vapor separator.Type: GrantFiled: September 27, 2016Date of Patent: June 18, 2019Assignee: Air Products and Chemicals, Inc.Inventors: Mark Julian Roberts, Gowri Krishnamurthy, Adam Adrian Brostow
-
Publication number: 20190162468Abstract: A system and method for increasing the efficiency of natural gas liquefaction processes by using a hybrid cooling system and method. More specifically, a system and method for converting a transcritical precooling refrigeration process to a subcritical process. In one embodiment, the refrigerant is cooled to sub-critical temperature using an economizer. In another embodiment, the refrigerant is cooled to a sub-critical temperature using an auxiliary heat exchanger. Optionally, the economizer or auxiliary heat exchanger can be bypassed when ambient temperatures are sufficiently low to cool the refrigerant to a sub-critical temperature. In another embodiment, the refrigerant is isentropically expanded.Type: ApplicationFiled: December 4, 2017Publication date: May 30, 2019Applicant: Air Products and Chemicals, Inc.Inventors: Gowri Krishnamurthy, Mark Julian Roberts