Abstract: The invention relates weldments useful as heat transfer tubes in pyrolysis furnaces. The invention relates to tubes that are useful in pyrolysis furnaces. The weldments include a tubular member and at least one mixing element. The tubular member comprises an aluminum-containing alloy. The mixing element comprises an aluminum-containing alloy. The mixing element's aluminum-containing alloy can be the same as or different from the tubular member's aluminum-containing alloy. Other aspects of the invention relate to pyrolysis furnaces which include such weldments, and the use of such pyrolysis furnaces for hydrocarbon conversion processes such as steam cracking.

Abstract: The invention relates a process for removing coke formed during steam-cracking of a hydrocarbon feed. The process includes providing a decoking feed to at least one radiant coil of a steam-cracking furnace under conditions to remove at least a portion of coke from the at least one radiant coil to form a decoking effluent. The decoking effluent is cooled with a liquid quench medium to provide an partially-quenched decoking effluent. The partially-quenched decoking effluent is cooled with a gaseous quench medium to provide a quenched effluent. An apparatus configured to perform such a process is also described.

Abstract: The present invention relates to a tube joint for joining first and second tubes located in a fired heater for heating process fluids, e.g., process heaters and heated tubular reactors both with and without catalyst. The tubes are joined in face-to-face contact, e.g., by welding the tube joint of the first tube to the tube joint of the second tube.

Abstract: Provided is a bimetallic tube for transport of hydrocarbon feedstocks in a petrochemical process unit and/or refinery process unit, including: i) an outer tube layer being formed from a steam cracker alloy including at least 18.0 wt. % Cr and at least 10.0 wt. % Ni; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt. % of Al, 18.0 wt. % to 25.0 wt. % Cr, less than 0.5 wt. % Si, and at least 35.0 wt. % Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof.

Abstract: A process for the on-stream decoking of a steam cracking furnace, the steam cracking furnace including multiple tube banks positioned between a hydrocarbon feedstock inlet and a convection section to radiant section crossover, each tube bank including a plurality of tubes arranged within the tube bank, the process comprising the steps of terminating the flow of hydrocarbon feed to a portion of the plurality of tubes of less than all of the multiple tube banks, and supplying a decoking feed comprising steam to the portion of the plurality of tubes of less than all of the multiple tube banks in sufficient amount to effect removal of coke accumulated on the interior of the radiant coils and quench system components fed by such tubes while maintaining a temperature at the convection section to radiant section crossover of below about 788° C. A furnace for the production of ethylene is also provided.

Abstract: The present invention relates to a tube joint for joining first and second tubes located in a fired heater for heating process fluids, e.g., process heaters and heated tubular reactors both with and without catalyst. The tubes are joined in face-to-face contact, e.g., by welding the tube joint of the first tube to the tube joint of the second tube.

Abstract: In one aspect, the present techniques include a heat exchange apparatus including: a) a body comprising an interior cavity, the body including: a first surface and a second surface defining at least a portion of the body and the first surface positioned exterior with respect to the second surface and the interior cavity, and the second surface positioned exterior with respect to the interior cavity and interior with respect to the first surface; b) a first conduit for conveying a fluid to the body; c) a second conduit in fluid communication with the first conduit wherein the second conduit is positioned at least partially within the interior cavity of the body; and d) a joint between the first conduit and the second conduit, wherein the joint moves between a first location and a second location based on the temperature within the interior cavity, wherein at least one of said first location and said second location is positioned intermediate the first surface and the second surface.

Abstract: A process for cracking a hydrocarbon feedstream containing non-volatile components in a hydrocarbon cracking furnace having upper and lower convection heating sections within a flue of the furnace, a radiant heating section downstream of and connected to said lower convection heating section, a transfer line exchanger downstream of and connected to said radiant heating section, a furnace box containing furnace burners and said radiant heating section, and a vapor/liquid separator vessel connected between the upper and lower convection heating sections, the process comprising (a) passing said hydrocarbon feedstream into said upper convection section to heat said hydrocarbon feedstream to a first temperature sufficient to flash at least a portion of the hydrocarbons within said hydrocarbon feedstream into a vapor phase to form a vapor/liquid stream; (b) passing said vapor/liquid stream out of said upper convection section and into said vapor/liquid separator to separate said vapor/liquid stream into a hydrocarb

Abstract: An improved burner and a method for combusting fuel used in furnaces such as those found in steam cracking. The burner includes a burner tube having a downstream end and an upstream end, a burner tip adjacent a first opening in the furnace, so that combustion of the fuel takes place at the burner tip, a lighting chamber adjacent to the first opening in the furnace, and a removable lighting chamber plug having a shape effective to substantially fill the lighting chamber when positioned within the lighting chamber.

Abstract: A process and apparatus for cracking a hydrocarbon feed in a steam cracking furnace by withdrawing a resid-rich stream from a resid knockout vessel and recycling the resid-rich stream through a convection heating section of the furnace.

Abstract: A process and apparatus are provided for cooling gaseous effluent from a hydrocarbon pyrolysis furnace, the cooling conduit apparatus including: (i) an inner wall for contacting the effluent, the inner wall defining a bore extending a length of the cooling conduit, the inner wall including a perimeter opening along the bore; (ii) an outer wall external to the inner wall and substantially coaxial to the inner wall; (iii) a substantially annular cavity external to the inner wall and including at least a portion of the outer wall, the annular cavity fluidly and remotely connected to the perimeter opening, the annular cavity externally surrounding a perimeter of the inner wall, the annular cavity including at least a portion of the outer wall; and (iv) a peripheral channel extending around a perimeter of the inner wall, the peripheral channel providing a channel flow path that fluidly connects the annular cavity with the remotely connected perimeter opening along the perimeter of the inner wall.

Abstract: Provided is a bimetallic tube for transport of hydrocarbon feedstocks in a petrochemical process unit and/or refinery process unit, including: i) an outer tube layer being formed from a steam cracker alloy including at least 18.0 wt. % Cr and at least 10.0 wt. % Ni; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt. % of Al, 18.0 wt. % to 25.0 wt. % Cr, less than 0.5 wt. % Si, and at least 35.0 wt. % Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof.

Abstract: A process and apparatus for steam cracking liquid hydrocarbon feedstocks utilizes a vapor/liquid separation apparatus to treat heated vapor/liquid mixtures to provide an overhead of reduced residue content and includes: i) indirectly heat exchanging liquid bottoms with boiler feed water to provide cooled liquid bottoms and preheated boiler feed water; ii) directing at least a portion of said preheated boiler feed water to a steam drum; and iii) recovering steam having a pressure of at least about 4100 kPa (600 psia) from said steam drum.

Abstract: A process and apparatus for cracking a hydrocarbon feed in a steam cracking furnace by withdrawing a resid-rich stream from a resid knockout vessel and recycling the resid-rich stream through a convection heating section of the furnace.

Abstract: A method is provided for treating the effluent from a hydrocarbon pyrolysis unit processing heavier than naphtha feeds to recover heat and remove tar therefrom. The method comprises passing the gaseous effluent to at least one primary transfer line heat exchanger, thereby cooling the gaseous effluent and generating superheated steam. Thereafter, the gaseous effluent is passed through at least one secondary transfer line heat exchanger having a heat exchange surface with a liquid coating on said surface, thereby further cooling the remainder of the gaseous effluent to a temperature at which tar, formed by the pyrolysis process, condenses. The condensed tar is then removed from the gaseous effluent in at least one knock-out drum. An apparatus for carrying out the method is also provided.

Abstract: A process and apparatus are provided for cooling gaseous effluent from a hydrocarbon pyrolysis furnace, the cooling conduit apparatus comprising: (i) an inner wall for contacting the effluent, the inner wall defining a bore extending a length of the cooling conduit, the inner wall including a perimeter opening along the bore; (ii) an outer wall external to the inner wall and substantially coaxial to the inner wall; (iii) a substantially annular cavity external to the inner wall and including at least a portion of the outer wall, the annular cavity fluidly and remotely connected to the perimeter opening, the annular cavity externally surrounding a perimeter of the inner wall, the annular cavity including at least a portion of the outer wall; and (iv) a peripheral channel extending around a perimeter of the inner wall, the peripheral channel providing a channel flow path that fluidly connects the annular cavity with the remotely connected perimeter opening along the perimeter of the inner wall.

Abstract: A process and apparatus for cracking a hydrocarbon feed in a steam cracking furnace by withdrawing a resid-rich stream from a resid knockout vessel and recycling the resid-rich stream through a convection heating section of the furnace.

Abstract: In one aspect, the present techniques include a heat exchange apparatus including: a) a body comprising an interior cavity, the body including: a first surface and a second surface defining at least a portion of the body and the first surface positioned exterior with respect to the second surface and the interior cavity, and the second surface positioned exterior with respect to the interior cavity and interior with respect to the first surface; b) a first conduit for conveying a fluid to the body; c) a second conduit in fluid communication with the first conduit wherein the second conduit is positioned at least partially within the interior cavity of the body; and d) a joint between the first conduit and the second conduit, wherein the joint moves between a first location and a second location based on the temperature within the interior cavity, wherein at least one of said first location and said second location is positioned intermediate the first surface and the second surface.

Abstract: A process and apparatus are provided for cooling gaseous effluent from a hydrocarbon pyrolysis furnace, the cooling conduit apparatus comprising: (i) an inner wall for contacting the effluent, the inner wall defining a bore extending a length of the cooling conduit, the inner wall including a perimeter opening along the bore; (ii) an outer wall external to the inner wall and substantially coaxial to the inner wall; (iii) a substantially annular cavity external to the inner wall and including at least a portion of the outer wall, the annular cavity fluidly and remotely connected to the perimeter opening, the annular cavity externally surrounding a perimeter of the inner wall, the annular cavity including at least a portion of the outer wall; and (iv) a peripheral channel extending around a perimeter of the inner wall, the peripheral channel providing a channel flow path that fluidly connects the annular cavity with the remotely connected perimeter opening along the perimeter of the inner wall.

Abstract: A furnace and method for the cracking of hydrocarbons. The furnace includes a radiant firebox, the radiant firebox comprising a furnace floor having a centerline, a plurality of decoke effluent injection nozzles mounted along or adjacent to the centerline for injecting decoke effluent upward into the radiant firebox, a plurality of burners arranged to form a first line of burners and a second line of burners, each line of burners positioned on opposing sides of the plurality of decoke effluent injection nozzles, a first plane of radiant coils spaced at a distance greater than the distance that the first line of burners is spaced from the centerline of the furnace floor and on the same side of the centerline as the first row of burners, and a second plane of radiant coils spaced at a distance greater than the distance that the second line of burners is spaced from the centerline of the furnace floor and on the same side of the centerline as the second row of burners.