Patents by Inventor Sergio Mohedas
Sergio Mohedas 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: 8088187Abstract: A method of utilizing hydrogen in synthesis gas production by forming synthesis gas from one or more carbonaceous materials, the synthesis gas comprising hydrogen and carbon monoxide; separating a hydrogen-rich product and a hydrogen-lean product from the synthesis gas to yield an adjusted synthesis gas product; and activating a hydrocarbon synthesis catalyst with at least a portion of the hydrogen-lean product. A system for carrying out the method is also provided, the system including at least one hydrogen extraction unit and an activation reactor operable to activate hydrocarbon synthesis catalyst, wherein the activation reactor comprises an inlet fluidly connected with the at least one hydrogen extraction unit whereby at least a portion of a hydrogen-lean gas stream, at least a portion of a hydrogen-rich gas stream, or at least a portion of both may be introduced into the activation reactor.Type: GrantFiled: September 10, 2008Date of Patent: January 3, 2012Assignee: Rentech, Inc.Inventors: Sergio Mohedas, Mark Ibsen
-
Publication number: 20110313061Abstract: A method of preparing a spray dried catalyst by combining spray dried catalyst particles with wax so the spray dried catalyst particles are coated with wax, yielding wax coated catalyst particles, and shaping the wax coated catalyst to provide shaped wax coated catalyst. A method of activating Fischer-Tropsch catalyst particles containing oxides by contacting the catalyst particles with a reducing gas in an activation vessel to produce an activated catalyst, wherein contacting is performed in the absence of a liquid medium under activation conditions. A system for activating a Fischer-Tropsch catalyst containing an activation reactor configured to introduce an activation gas to a fixed or fluidized bed of the Fischer-Tropsch catalyst in the absence of a liquid medium and at least one separation device configured to separate a gas stream comprising entrained catalyst fines having an average particle size below a desired cutoff size from the activation reactor.Type: ApplicationFiled: January 5, 2011Publication date: December 22, 2011Applicant: RENTECH, INC.Inventors: Harold A. Wright, Belma Demirel, Sergio Mohedas, Bahman Rejai, Ray Huang, Deena Ferdous, Jesse W. Taylor, Dawid J. Duvenhage, Sara L. Rolfe
-
Publication number: 20100160156Abstract: A system for activating Fischer-Tropsch catalyst comprising a reactor having a reactor outlet for overhead gas and operable under suitable conditions whereby a catalyst in a volume of liquid carrier comprising Fischer-Tropsch diesel, hydrocracking recycle oil, or a combination thereof may be activated in the presence of an activation gas; a condenser comprising an inlet fluidly connected to the reactor outlet for overhead gas and comprising a condenser outlet for condensed liquids; and a separation unit comprising an inlet fluidly connected to the condenser outlet and a separator outlet for a stream comprising primarily Fischer-Tropsch diesel; and a recycle line fluidly connecting the separator outlet, a hydrocracking unit, or both to the reactor, whereby Fischer-Tropsch diesel recovered from the reactor overhead gas, hydrocracking recycle oil, or a combination thereof may serve as liquid carrier for catalyst in the reactor. A method for activating Fischer-Tropsch catalyst is also provided.Type: ApplicationFiled: December 14, 2009Publication date: June 24, 2010Applicant: RENTECH, INC.Inventors: Mark Ibsen, Sergio Mohedas
-
Publication number: 20100113622Abstract: A system for separating liquids from solids comprising an immobilization unit comprising an immobilization vessel containing a bed of magnetizable material and a magnet configured to produce a magnetic field within the immobilization vessel, wherein the immobilization vessel further comprises an immobilization vessel outlet and an immobilization vessel inlet for a fluid comprising liquid and metal-containing particles.Type: ApplicationFiled: October 12, 2009Publication date: May 6, 2010Applicant: RENTECH, INC.Inventors: Sergio MOHEDAS, Harold A. WRIGHT
-
Publication number: 20090068073Abstract: A catalyst loading system comprising: a vessel comprising at least one gas distribution nozzle at or near the bottom of the vessel, a top fluid distributor located at or near the top of the vessel, a catalyst inlet through which catalyst is introduced into the vessel, a first contact point at which catalyst introduced into the vessel first contacts the contents of the vessel, and a discharge outlet whereby catalyst exits the vessel. Methods of preparing catalyst slurry for introduction into a downstream reactor or in-situ activation within the vessel utilizing the catalyst loading system are also disclosed.Type: ApplicationFiled: September 10, 2008Publication date: March 12, 2009Applicant: RENTECH, INC.Inventors: Mark Anselmo, Derek Bridgford, Nick Cozzi, Sergio Mohedas, Matt Greer, Paul Morton
-
Publication number: 20090064584Abstract: A method of utilizing hydrogen in synthesis gas production by forming synthesis gas from one or more carbonaceous materials, the synthesis gas comprising hydrogen and carbon monoxide; separating a hydrogen-rich product and a hydrogen-lean product from the synthesis gas to yield an adjusted synthesis gas product; and activating a hydrocarbon synthesis catalyst with at least a portion of the hydrogen-lean product. A system for carrying out the method is also provided, the system including at least one hydrogen extraction unit and an activation reactor operable to activate hydrocarbon synthesis catalyst, wherein the activation reactor comprises an inlet fluidly connected with the at least one hydrogen extraction unit whereby at least a portion of a hydrogen-lean gas stream, at least a portion of a hydrogen-rich gas stream, or at least a portion of both may be introduced into the activation reactor.Type: ApplicationFiled: September 10, 2008Publication date: March 12, 2009Applicant: RENTECH, INC.Inventors: Sergio Mohedas, Mark Ibsen
-
Publication number: 20090069450Abstract: A catalytic reaction system comprising: a catalytic reactor fluidly connected with at least two slurry loops, wherein the reactor comprises at least as many reactor product outlets and at least as many slurry return inlets as slurry loops; wherein each slurry loop comprises a separation system comprising a separation system inlet, a separation system product outlet, and a concentrated catalyst slurry outlet; a slurry offtake fluidly connecting the separation system inlet with one of the reactor product outlets; and a slurry return fluidly connecting the separation system outlet with one of the slurry return inlets. The system may comprise at least three slurry loops. The system may comprise at least four slurry loops. A method for converting synthesis gas into liquid hydrocarbons via the catalytic reaction system in also disclosed.Type: ApplicationFiled: September 8, 2008Publication date: March 12, 2009Applicant: RENTECH, INC.Inventors: Mark Ibsen, Sergio Mohedas, Frank Hogsett, Mark Bohn, Harold A. Wright
-
Publication number: 20090065437Abstract: A system for separating particulate from a fluid stream having an inlet solids content, the system comprising: a magnetic dynamic settling vessel comprising at least one magnetic field inside the vessel and/or one magnetized component; at least one inlet for introduction of the fluid stream having a starting solids content; at least one exit for a stream comprising a solids content not greater than the inlet solids content; at least one exit for a fluid stream comprising a solids content not less than the inlet solids content; and a vertical feed conduit extending at least 70% of the distance from the at least one fluid inlet to the at least one exit for a fluid stream comprising a solids content not less than the inlet solids content. A method for separating particulate from a fluid stream having an inlet solids content is also provided.Type: ApplicationFiled: September 8, 2008Publication date: March 12, 2009Applicant: RENTECH, INC.Inventor: Sergio MOHEDAS
-
Publication number: 20050209350Abstract: A method for selecting maximum and minimum catalyst particle sizes for use in a multiphase reactor that reflects optimum operating conditions of the reactor is based on a maximum Archimedes number for estimating the maximum particle size and a property of a separation system linked to the reactor to determine the minimum particle size. The maximum Archimedes number could be selected based on a maximum catalyst non-uniformity in the reactor. Additionally, a method for producing hydrocarbons from syngas in a slurry bubble column reactor comprises the use of a plurality of fresh catalyst particles with an optimum size distribution based on a range of Archimedes numbers between about 0.02 and 250 or alternatively based on an average Reynolds number less than about 0.1.Type: ApplicationFiled: March 18, 2004Publication date: September 22, 2005Applicant: ConocoPhillips CompanyInventors: Rafael Espinoza, Oluwaseyi Odueyungbo, Jianping Zhang, Sergio Mohedas
-
Publication number: 20050209351Abstract: The invention relates to methods for prevention of and recovery from a catalyst bed slumping in a gas-agitated multiphase hydrocarbon synthesis reactor, while the reactor is either under non-reactive conditions or under reaction promoting conditions when syngas is converted to products. The reactor contains a catalyst bed comprising catalyst particles and a gas injection zone suitable for injecting a reactor gas feed. A method for preventing bed slumping comprises supplying a supplemental gas to the gas-agitated multiphase reactor to prevent the catalyst bed from slumping due to insufficient reactor gas feed flow. The method may include recycling some or all of the supplemental gas to the reactor. The method may further comprise separating the gas injection zone from the catalyst bed with a porous plate so as to prevent migration of catalyst particles into the gas injection zone and to minimize plugging of gas distributor(s) present in said zone.Type: ApplicationFiled: March 19, 2004Publication date: September 22, 2005Applicant: ConocoPhillips CompanyInventors: Sergio Mohedas, Rafael Espinoza, Jack Cnossen, Todd Harkins, Vincent Melquist, Larry Swinney
-
Publication number: 20050182145Abstract: The present methods feature an overall decrease in transportation costs and catalyst preparation/protection measures. A catalyst comprising a catalytic metal in an oxide form is safely transported in an oxidizing environment to a synthesis site, without any special precautions being taken before and during transport. The catalyst is then reduced with a reducing gas at the synthesis plant. The reduced catalyst is mixed with a stripped hydrocarbon liquid to form a catalyst slurry, wherein the stripped hydrocarbon liquid is substantially free of dissolved oxygen after being contacted with a stripping gas. The mixing can take place in a pre-operational hydrocarbon synthesis reactor, or at least a portion of the slurry can be transferred to at least one synthesis reactor either during operation or at the reactor start-up. A lessening of costs is realized as a coating step to minimize oxidative degradation of the catalyst is not required.Type: ApplicationFiled: February 17, 2004Publication date: August 18, 2005Applicant: ConocoPhillips CompanyInventors: Sergio Mohedas, Rafael Espinoza, Ajoy Raje, Kevin Coy
-
Patent number: 6914082Abstract: A gas-agitated multiphase reactor system for the synthesis of hydrocarbons gives high catalyst productivity and reactor capacity. The system includes operating a multi-phase reactor in the well-mixed gas flow regime, with a Peclet number less than 0.175 and a single pass conversion ranging from 35% to 75%, wherein the inlet superficial gas velocity decreases with the decreasing of the reactor aspect ratio, and is preferably at least 20 cm/sec.Type: GrantFiled: December 14, 2001Date of Patent: July 5, 2005Assignee: ConocoPhillips CompanyInventors: Jianping Zhang, Rafael L. Espinoza, Sergio Mohedas
-
Publication number: 20050027021Abstract: Methods and apparatus for removing wax products from a slurry used in a Fischer-Tropsch reactor. The preferred embodiments of the present invention are characterized by a solid/liquid separation system that removes liquid products from a slurry by drawing the fluid across a filter medium composed of a filter cake disposed on a substrate. In the preferred embodiments, the filter cake is desirable and performs the majority of the filtration. In certain embodiments, the filter medium is disposed in a filter housing where slurry flows parallel to the longitudinal axis of the filter medium from and inlet to an outlet. The characteristics or properties of the cake, which will effect the performance of the solid/liquid separation system, can be controlled by regulating the velocity of the slurry flowing across the cake, where the velocity may be regulated by adjusting the slurry flow through the filter housing or may be self-regulated by changing slurry velocities influenced by the design of the filter housing.Type: ApplicationFiled: April 16, 2003Publication date: February 3, 2005Applicant: ConocoPhillips CompanyInventors: Rafael Espinoza, Sergio Mohedas, Doug Jack, Oluwaseyi Odueyungbo, James Ortego
-
Patent number: 6720358Abstract: The present invention relates to a method and system for water removal and optionally liquid product separation in slurry reactors operating at Fischer-Tropsch conditions. More particularly, the present invention includes a water stripping system that allows the reaction water to the stripped in an external vessel, with a relatively high rate of catalyst and wax circulation. In a preferred embodiment of the present invention, a method for removing water from a slurry reactor containing a water-rich slurry includes removing a portion of water-rich slurry from the slurry reactor, stripping water from the water-rich slurry using a dry gas to form a water-reduced slurry and a water-rich gas stream, and returning the water-reduced slurry back to the reactor.Type: GrantFiled: December 28, 2001Date of Patent: April 13, 2004Assignee: ConocoPhillips CompanyInventors: Rafael L. Espinoza, Sergio Mohedas, Vincent Melquist
-
Publication number: 20030125396Abstract: The present invention relates to a method and system for water removal and optionally liquid product separation in slurry reactors operating at Fischer-Tropsch conditions. More particularly, the present invention includes a water stripping system that allows the reaction water to the stripped in an external vessel, with a relatively high rate of catalyst and wax circulation. In a preferred embodiment of the present invention, a method for removing water from a slurry reactor containing a water-rich slurry includes removing a portion of water-rich slurry from the slurry reactor, stripping water from the water-rich slurry using a dry gas to form a water-reduced slurry and a water-rich gas stream, and returning the water-reduced slurry back to the reactor.Type: ApplicationFiled: December 28, 2001Publication date: July 3, 2003Inventors: Rafael L. Espinoza, Sergio Mohedas, Vincent Melquist
-
Publication number: 20030114543Abstract: A gas-agitated multiphase reactor system for the synthesis of hydrocarbons gives high catalyst productivity and reactor capacity. The system includes operating a multi-phase reactor in the well-mixed gas flow regime, with a Peclet number less than 0.175 and a single pass conversion ranging from 35% to 75%, wherein the inlet superficial gas velocity decreases with the decreasing of the reactor aspect ratio, and is preferably at least 20 cm/sec.Type: ApplicationFiled: December 14, 2001Publication date: June 19, 2003Inventors: Jianping Zhang, Rafael L. Espinoza, Sergio Mohedas