Abstract: A cracking furnace within the firebox of which is located a ceramic structure presenting opposing wall surfaces which thereby define a slot-like passageway through which hydrocarbons may be fed through the firebox of the furnace. This ceramic structure is capable of service under much greater heat loads and temperatures than are metallic reaction lines as have heretofore been used, allowing for a greater firebox temperature which in turn produces an even more rapid cracking of saturated hydrocarbon into ethylene at millisecond residence times within the firebox limits.
Abstract: A furnace construction for cracking of saturated hydrocarbon feed stocks to olefinic product mixtures, wherein the reaction lines of such furnace are fabricated of a ceramic refractory feed inlet pipe coaxially located with a ceramic refractory tube to define an annular space there between which in part is located without and within the radiant heating firebox volume of such furnace, this to provide for a zone wherein hot cracked olefin product gas is quenched in temperature in such annular space outside of such firebox and a cracking zone within the firebox within which hydrocarbon feed is cracked to an olefin containing product gas composition. The ceramic refractory material construction permits of such pipe-tube reaction line structure to be exposed to a much greater heat/temperature content of which the firebox is capable than reaction lines of metallic construction.
Abstract: The invention relates to a new process for more efficient separation and recovery of light olefins such as ethylene and propylene from a fluid catalytic cracking unit. The new process invention for recovering olefins from a mixture of cracked hydrocarbons from a fluid catalytic cracker comprises the steps of: (a) providing a mixture of cracked hydrocarbons including methane, ethylene, ethane, propylene, propane, butylene, butane and heavier hydrocarbons such as naphtha produced in a fluid catalytic cracker; (b) separating said mixture into (i) a first stream comprising substantially all of said ethane, ethylene, and methane and a major portion of said propane and propylene and (ii) a second stream comprising a portion of said butylene and butane, and a major portion of said heavier hydrocarbons; and (c) processing said first stream to recover the ethylene and propylene therefrom, and the details of such process described herein.
Type:
Grant
Filed:
February 22, 1999
Date of Patent:
August 7, 2001
Assignee:
Stone & Webster Engineering Corp.
Inventors:
Ginger S. Keady, Juan Puerto, Berj Garbouchian
Abstract: An inline, high-shear mixer is provided in a cracked gas stream upstream of a caustic tower in an ethylene production unit. Spent caustic is withdrawn from the bottom of the caustic tower and pumped to the mixer, where the spent caustic mixes with and absorbs acid gas components from the cracked gas stream. The spent caustic is separated from the cracked gas, forming a partially treated cracked gas stream. The partially treated cracked gas stream is then fed to the caustic tower. Polymer deposition in the caustic tower is reduced because polymeric material is formed when the cracked gas stream is mixed with the spent caustic and is removed before the cracked gas stream is fed to the caustic tower.
Abstract: A process for pre-treating a spent caustic stream prior to oxidation which includes countercurrent multi-stage elevated temperature solvent extraction of dissolved organic material from the spent caustic using a solvent to yield a spent caustic raffinate containing only residual amounts of organic solute and steam distilling the spent caustic raffinate to remove the residual organic solutes, yielding a pretreated spent caustic stream substantially free of organic material which is then subjected to wet air oxidation and thereafter to ozonolysis to yield a wastewater stream having a low COD and BOD, which is neutralized to a pH of 8.5 to 9.0.
Type:
Grant
Filed:
December 17, 1998
Date of Patent:
April 3, 2001
Assignee:
Stone & Webster Engineering
Inventors:
Sabah A. Kurukchi, Joseph M. Gondolfe, Stephen Z. Masoomian
Abstract: A novel process is provided which integrates the cracking of hydrocarbon containing feedstocks with the olefins purification and olefins derivative process utilizing dilute olefin feedstocks.
Abstract: A process for producing liquid fuels from heavy hydrocarbons such as residual oil in which the cracking temperatures are in the range of 800.degree. F. to 1200.degree. F., and the residence times are between 0.05 seconds and 0.50 seconds.
Type:
Grant
Filed:
December 14, 1995
Date of Patent:
November 2, 1999
Assignee:
Stone & Webster Engineering Corp.
Inventors:
Axel R. Johnson, Robert J. Gartside, Joseph L. Ross, Dennis A. Duncan
Abstract: The present invention provides a process and system for the removal of butadiene from a cracked gas stream prior to entering a front end hydrogenation reactor in an olefin production facility.
Abstract: The invention provides a process for treating a sulfide-containing alkaline aqueous effluent, which includes subjecting it to a wet air oxidation treatment which oxidizes sulfide ions to environmentally acceptable sulfur acid ions, the oxidation being carried out in two or more chambers connected in series, flow of effluent between the chambers being effected at least primarily by gravity such that the pressures in the respective chambers can be maintained at substantially the same value.
Abstract: A process for pretreating a spent caustic stream prior to oxidation includes countercurrent multi-stage elevated temperature solvent extraction of dissolved organic material from the spent caustic using a solvent to yield a spent caustic raffinate containing only residual amounts of organic solute. The raffinate is steam distilled to remove the residual organic solutes, yielding a pretreated spent caustic stream substantially free of organic material. The pretreated spent caustic is suitable for use in a Kraft paper process or for oxidation prior to recycle or disposal. Solvent extract from the extractor is regenerated in a solvent regenerator having an overhead stream for purging light ends, a bottom stream for purging heavy ends, and a heart-cut side stream for recycling solvent to the extractor.
Abstract: The present invention provides an improved method for recovering high purity olefins from cracked gas effluents or other parafin/olefin gaseous mixtures by use of a chemical absorption process.
Type:
Grant
Filed:
December 13, 1996
Date of Patent:
January 12, 1999
Assignee:
Stone & Webster Engineering Corp.
Inventors:
Richard Barchas, Richard McCue, Jr., Christopher Wallsgrove, Mark Whitney
Abstract: The invention is a process and apparatus for rapidly and efficiently separating a fluidized catalytic cracking mixture into cracking catalysts and hydrocarbon vapor. The invention decreases the production of unwanted hydrocarbon byproducts by decreasing the contact time between the separated hydrocarbon vapor and the cracking catalyst.
Abstract: A process and system for providing cooling service (refrigerant) for a gas separation process wherein the refrigerant is obtained from the system process fluid and after serving as refrigerant is returned to the process side for separation into product.
Type:
Grant
Filed:
April 16, 1997
Date of Patent:
June 23, 1998
Assignee:
Stone & Webster Engineering Corp.
Inventors:
Richard H. McCue, Jr., Mark Whitney, John L. Pickering, Jr., David Chen
Abstract: The present invention provides an apparatus for improving the contacting of feedstock and regenerated catalytic particulates in certain fluid catalytic cracking processes and apparatus.
Abstract: The present invention provides a process and system for the removal of butadiene from a cracked gas stream prior to entering a front end hydrogenation reactor in an olefin production facility.
Abstract: A process for contemporaneously catalytically cracking a paraffin rich feedstock and a heavy feedstock wherein the feedstocks are segregated prior to catalytic cracking in separate reactors with regenerated particulate catalyst solids. The process provides for the separate optimal cracking of paraffinic constituents and heavy naphthenic constituents while maintaining an overall heat balance.
Type:
Grant
Filed:
July 16, 1996
Date of Patent:
March 24, 1998
Assignee:
Stone & Webster Engineering Corporation
Inventors:
Axel R. Johnson, Joseph L. Ross, Atulya V. Saraf
Abstract: The present invention provides a method for improving the contacting of feedstock and regenerated catalytic particulates in certain fluid catalytic cracking processes and apparatus.
Abstract: A novel apparatus and process for the cracking of hydrocarbons is disclosed which is particularly useful in revamping an existing FCC unit to a short residence time FCC unit.
Abstract: A catalyst cooler apparatus and process for use with a two-stage regeneration system in a fluidized catalytic cracking process having a device to remove hot catalyst from the second regeneration zone at a point above the air distribution ring under the surface of the catalyst bed equivalent to the catalyst exit to the reactor, a heat exchanger for indirect heat exchange and cooling of the catalyst and a return device for returning the cooled catalyst to the second regeneration zone at or near the bottom of the catalyst bed, beneath the air distribution ring.
Type:
Grant
Filed:
April 27, 1992
Date of Patent:
November 5, 1996
Assignee:
Stone & Webster Engineering Corporation
Inventors:
Steve L. Long, Joseph L. Ross, Gautham Krishnaiah