Abstract: In a system for thermal cracking gaseous feedstocks, the system including a gas cracker for producing an effluent comprising olefins, at least one transfer line exchanger for the recovery of process energy from the effluent and a water quench tower system, a process for extending the range of system feedstocks to include liquid feedstocks that yield tar is provided. The process includes the steps of injecting a first quench fluid downstream of the at least one transfer line exchanger to quench the process effluent comprising olefins, separating in a separation vessel a cracked product and a first byproduct stream comprising tar from the quenched effluent, directing the separated cracked product to the water quench tower system and quenching the separated cracked product with a second quench fluid to produce a cracked gas effluent for recovery and a second byproduct stream comprising tar. An apparatus for cracking a liquid hydrocarbon feedstock that yield tar is also provided.

Abstract: An apparatus for on-line cleaning and maintaining the cleanliness of a transfer line exchanger tube is provided. In one embodiment, the apparatus includes a housing having a first end, a second end and a longitudinal axis, the housing further including a first inlet for introducing a flushing fluid to the transfer line exchanger tube, the first inlet disposed proximate the first end of the housing, a second inlet for providing a product effluent comprising hydrocarbons and an outlet for placing in fluid communication with an inlet of the transfer line exchanger tube and a critical flow nozzle or flow control orifice, the critical flow nozzle or flow control orifice in fluid communication with the first inlet of the housing. Systems and processes for cleaning and maintaining the cleanliness of a transfer line exchanger are also disclosed.

Abstract: A process for cracking hydrocarbon feedstock containing resid comprising: heating the feedstock, mixing the heated feedstock with a fluid and/or a primary dilution steam stream to form a mixture, flashing the mixture to form a vapor phase and a liquid phase which collect as bottoms and removing the liquid phase, separating and cracking the vapor phase, and cooling the product effluent, wherein the bottoms are maintained under conditions to effect at least partial visbreaking. The visbroken bottoms may be steam stripped to recover the visbroken molecules while avoiding entrainment of the bottoms liquid. An apparatus for carrying out the process is also provided.

Abstract: A process for decoking a convection section of a furnace for cracking a hydrocarbon feed, the furnace comprising a radiant section having burners that generate radiant heat and hot flue gas, and the convection section having at least one heat exchange tube for conveying the hydrocarbon feed. The process includes the step of establishing a flue gas temperature within the convection section of the furnace immediately adjacent the at least one convection section heat exchange tube so as to effect a film surface temperature of less than about 540° C. (about 1000° F.) within at least one convection section heat exchange tube, wherein said flue gas temperature establishing step is effective to decoke the at least one convection section heat exchange tube. A process for cracking hydrocarbon feed in a furnace is also provided.

Abstract: The invention concerns integration of hydroprocessing and steam cracking. A feed comprising crude or resid-containing fraction thereof is treated by hydroprocessing and visbreaking and then passed to a steam cracker to obtain a product comprising olefins.

Abstract: In one aspect, the inventive process comprises a process for pyrolyzing a hydrocarbon feedstock containing nonvolatiles in a regenerative pyrolysis reactor system. The inventive process comprises: (a) heating the nonvolatile-containing hydrocarbon feedstock upstream of a regenerative pyrolysis reactor system to a temperature sufficient to form a vapor phase that is essentially free of nonvolatiles and a liquid phase containing the nonvolatiles; (b) separating said vapor phase from said liquid phase; (c) feeding the separated vapor phase to the pyrolysis reactor system; and (d) converting the separated vapor phase in said pyrolysis reactor system to form a pyrolysis product.

Abstract: In one aspect, the inventive process comprises a process for pyrolyzing a hydrocarbon feedstock containing nonvolatiles in a regenerative pyrolysis reactor system. The inventive process comprises: (a) heating the nonvolatile-containing hydrocarbon feedstock upstream of a regenerative pyrolysis reactor system to a temperature sufficient to form a vapor phase that is essentially free of nonvolatiles and a liquid phase containing the nonvolatiles; (b) separating said vapor phase from said liquid phase; (c) feeding the separated vapor phase to the pyrolysis reactor system; and (d) converting the separated vapor phase in said pyrolysis reactor system to form a pyrolysis product.

Abstract: A process and apparatus are provided for upgrading steam cracker tars from steam crackers. The invention also relates to a steam cracking process and apparatus for reducing yields of tars produced from steam cracking while increasing yields of higher value products by heating steam cracker tar, in the presence of hydrogen donor compounds, e.g., tetralin. The hydrogen donor compounds can be provided in a hydrogen donor-rich hydrocarbon stream, e.g., light cycle oils, or low sulfur vacuum tower bottoms. The treated tar can be separated into gas oil, fuel oil and tar streams.

Abstract: The invention relates to a process for upgrading tar using a heat exchanger in series with a vapor/liquid separator to separate tar into a heavy tar asphaltenic material and a deasphalted tar material.

Abstract: A process for cracking heavy hydrocarbon comprising heating the heavy hydrocarbon feedstock, mixing the heavy hydrocarbon feedstock with a fluid and/or a primary dilution steam stream to form a mixture, flashing the mixture to form a vapor phase and a liquid phase, separating and cracking the vapor phase, and cooling the product effluent in a transfer line exchanger, wherein the amount of the fluid and/or the primary dilution steam stream mixed with the heavy hydrocarbon feedstock is varied in accordance with at least one selected operating parameter of the process, such as the temperature of the flash stream before entering the flash/separator vessel.

Abstract: A feedstream comprising tar is fed to a solvent deasphalter wherein it is contacted with a deasphalting solvent or fluid to produce a composition comprising a mixture or slurry of solvent containing a soluble portion of the tar, and a heavy tar fraction comprising the insoluble portion of the tar. These fractions may be separated in the deasphalter apparatus, such as by gravity settling wherein the heavy tar fraction is taken off as bottoms, and the solvent-soluble fraction taken as overflow or overheads with the solvent. The overflow or overheads is sent to a solvent recovery unit, such as a distillation apparatus, wherein solvent is recovered as overheads and a deasphalted tar fraction is taken off as a sidestream or bottoms. The solvent or a portion thereof, recovered as overheads, may be then be recycled to the solvent deasphalter, or in a preferred embodiment, at least a portion of the solvent is steam cracked to produce a product comprising light olefins.

Abstract: A process for reducing the rate of increase in pressure drop across a furnace convection section, the furnace convection section having a temperature profile. The process includes the steps of establishing a ratio of total dilution H2O to feedstock for the system, injecting a first portion of the total dilution H2O in the form of water into the convection section of the furnace, injecting a second portion of the dilution H2O in the form of steam into the convection section of the furnace, wherein a ratio of dilution H2O in the form of water to dilution H2O in the form of steam is established and varying the temperature profile across the convection section of the furnace by adjusting periodically the ratio of dilution H2O in the form of water to dilution H2O in the form of steam. A similar technique is conducted during decoking to remove asphaltene coke starting from the lower convection section upward.

Abstract: The invention relates to a method for processing asphaltene-containing feed to a pyrolysis furnace by raising the final boiling point of the feed/steam mixture to the pyrolysis furnace to ensure fouling occurs lower in the convection section where the mixture of air and steam can burn off fouling deposits during decoking operations. The final boiling point of the feed stream is increased by adding a heavy essentially asphaltene-free high boiling point hydrocarbon to the feed stream before the feed stream enters the convection section of the pyrolysis furnace, whereby said fouling occurs lower in the convection section.

Abstract: In a system for thermal cracking gaseous feedstocks, the system including a gas cracker for producing an effluent comprising olefins, at least one transfer line exchanger for the recovery of process energy from the effluent and a water quench tower system, a process for extending the range of system feedstocks to include liquid feedstocks that yield tar is provided. The process includes the steps of injecting a first quench fluid downstream of a primary transfer line exchanger to quench the process effluent comprising olefins, separating in a first separation vessel a cracked product and a first byproduct stream comprising tar from the quenched effluent, directing the separated cracked product to a water quench tower system and quenching the separated cracked product with a second quench fluid to produce a cracked gas effluent for recovery and a second byproduct stream comprising tar. An apparatus for carrying out such process is also provided.

Abstract: Tar is contacted with stripping agent, such as steam or tail gas, in a stripping tower. A product comprising deasphalted tar is recovered as overheads and a product comprising heavy tar is recovered as bottoms from the stripping tower.

Abstract: A process for steam cracking liquid hydrocarbon feedstocks containing synthetic crude oil comprises i) hydroprocessing a wide boiling range aliquot containing a) normally liquid hydrocarbon portion substantially free of resids and b) thermally cracked hydrocarbon liquid, boiling in a range from about 600° to about 1050° F., to provide a synthetic crude oil substantially free of resids; ii) adding to the synthetic crude oil a normally liquid hydrocarbon component boiling in a range from about 100° to about 1050° F.; and iii) cracking the mixture resulting from ii) in a cracker furnace comprising a radiant coil outlet to provide a cracked effluent, wherein the cracking is carried out under conditions sufficient to effect a radiant coil outlet temperature which is greater than the optimum radiant coil outlet temperature for cracking the synthetic crude oil separately. A method for upgrading synthetic crude for use in cracking is also provided, as well as a feedstock for cracking.

Abstract: In a system for thermal cracking gaseous feedstocks, the system including a gas cracker for producing an effluent comprising olefins, at least one transfer line exchanger for the recovery of process energy from the effluent and a water quench tower system, a process for extending the range of system feedstocks to include liquid feedstocks that yield tar is provided. The process includes the steps of injecting a first quench fluid downstream of the at least one transfer line exchanger to quench the process effluent comprising olefins, separating in a separation vessel a cracked product and a first byproduct stream comprising tar from the quenched effluent, directing the separated cracked product to the water quench tower system and quenching the separated cracked product with a second quench fluid to produce a cracked gas effluent for recovery and a second byproduct stream comprising tar. An apparatus for cracking a liquid hydrocarbon feedstock that yield tar is also provided.

Abstract: A process for cracking hydrocarbon feedstock containing resid comprising: heating the feedstock, mixing the heated feedstock with a fluid and/or a primary dilution steam stream to form a mixture, flashing the mixture to form a vapor phase and a liquid phase which collect as bottoms and removing the liquid phase, separating and cracking the vapor phase, and cooling the product effluent, wherein the bottoms are maintained under conditions to effect at least partial visbreaking. The visbroken bottoms may be steam stripped to recover the visbroken molecules while avoiding entrainment of the bottoms liquid. An apparatus for carrying out the process is also provided.

Abstract: In a system for thermal cracking gaseous feedstocks, the system including a gas cracker for producing an effluent comprising olefins, at least one transfer line exchanger for the recovery of process energy from the effluent and a water quench tower system, a process for extending the range of system feedstocks to include liquid feedstocks that yield tar is provided. The process includes the steps of injecting a first quench fluid downstream of a primary transfer line exchanger to quench the process effluent comprising olefins, separating in a first separation vessel a cracked product and a first byproduct stream comprising tar from the quenched effluent, directing the separated cracked product to a water quench tower system and quenching the separated cracked product with a second quench fluid to produce a cracked gas effluent for recovery and a second byproduct stream comprising tar. An apparatus for carrying out such process is also provided.

Abstract: A process for feeding or cracking heavy hydrocarbon feedstock containing non-volatile hydrocarbons comprising: heating the heavy hydrocarbon feedstock, mixing the heavy hydrocarbon feedstock with a fluid and/or a primary dilution steam stream to form a mixture, flashing the mixture to form a vapor phase and a liquid phase, and varying the amount of the fluid and/or the primary dilution steam stream mixed with the heavy hydrocarbon feedstock in accordance with at least one selected operating parameter of the process, such as the temperature of the flash stream before entering the flash drum.