Abstract: Hydrocarbon feedstock containing resid is cracked by a process comprising: (a) heating the hydrocarbon feedstock; (b) mixing the heated hydrocarbon feedstock with steam and optionally water to form a mixture stream; (c) introducing the mixture stream to a flash/separation apparatus to form i) a vapor phase at its dew point which partially cracks and loses/or heat causing a temperature decrease and partial condensation of the vapor phase in the absence of added heat to provide coke precursors existing as uncoalesced condensate, and ii) a liquid phase; (d) removing the vapor phase as overhead and the liquid phase as bottoms from the flash/separation apparatus; (e) treating the overhead by contacting with a hydrocarbon-containing nucleating liquid substantially free of resid and comprising components boiling at a temperature of at least about 260° C. (500° F.

Abstract: A process and control system for cracking a heavy hydrocarbon feedstock containing non-volatile hydrocarbons comprising heating the heavy hydrocarbon feedstock, mixing the heated heavy hydrocarbon feedstock with a dilution steam stream to form a mixture stream having a vapor phase and a liquid phase, separating the vapor phase from the liquid phase in a separation vessel, and cracking the vapor phase in the furnace, wherein the furnace draft is continuously measured and periodically adjusted to control the temperature of the stream entering the vapor/liquid separator and thus controlling the ratio of vapor to liquid separated in the separation vessel; and wherein in a preferred embodiment the means for adjusting the draft comprises varying the speed of at least one furnace fan, possibly in combination with adjusting the position of the furnace fan damper(s) or the furnace burner dampers(s).

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: A highly efficient vapor/liquid separation apparatus for treating a flow of vapor/liquid mixtures of hydrocarbons and steam comprises a substantially cylindrical vertical drum having an upper cap section, a middle section comprising a circular wall, a lower cap section, a tangential inlet to introduce hydrocarbon/steam mixtures, an overhead vapor outlet, and a bottom outlet for liquid. The vessel also comprises an annular structure located in the middle section, comprising i) an annular ceiling section extending from the circular wall and ii) a concentric internal vertical side wall to which the ceiling section extends. The annular structure blocks upward passage of vapor/liquid mixtures along the circular wall beyond the ceiling section, and surrounds an open core having sufficient cross-sectional area to permit vapor velocity low enough to avoid significant entrainment of liquid.

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.

Abstract: A process is provided 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, optionally further heating the mixture, flashing the mixture within a flash/separation vessel to form a vapor phase and a liquid phase, partially condensing the vapor phase by contacting with a condenser within the vessel, to condense at least some coke precursors within the vapor while providing condensates which add to the liquid phase, removing the vapor phase of reduced coke precursors content as overhead and the liquid phase as bottoms, heating the vapor phase, cracking the vapor phase in a radiant section of a pyrolysis furnace to produce an effluent comprising olefins, and quenching the effluent and recovering cracked product therefrom. An apparatus for carrying out the process is also provided.

Abstract: A process for reducing fouling during cracking of a hydrocarbon feedstock containing resid is provided which comprises: introducing a mixture stream of heated hydrocarbon feedstock mixed with steam to a flash/separation apparatus to form i) a vapor phase at its dew point which partially cracks causing a temperature decrease and partial condensation of said vapor phase in the absence of added heat, and ii) a liquid phase. Partial condensation is reduced by adding a heated vaporous diluent, e.g., light hydrocarbon or superheated steam, to the flash/separation apparatus to an extent sufficient to at least partially compensate for the temperature decrease and to dilute and superheat the vapor phase, prior to removing the vapor phase as overhead for subsequent cracking and recovery of cracked product. An apparatus for carrying out the process is also provided.

Abstract: A process for decoking of a process that cracks hydrocarbon feedstock containing resid and coke precursors, wherein steam is added to the feedstock to form a mixture which is thereafter separated into a vapor phase and a liquid phase by flashing in a flash/separation vessel, separating and cracking the vapor phase, and recovering cracked product. Coking of internal surfaces in and proximally downstream of the vessel is controlled by interrupting the feed flow, purging the vessel with steam, introducing an air/steam mixture to at least partially combust the coke, and resuming the feed flow when sufficient coke has been removed. An apparatus for carrying out the process is also provided.

Abstract: A process for reducing fouling during cracking of a hydrocarbon feedstock containing resid is provided which comprises: introducing a mixture stream of heated hydrocarbon feedstock mixed with steam to a flash/separation apparatus to form i) a vapor phase at its dew point which partially cracks causing a temperature decrease and partial condensation of said vapor phase in the absence of added heat, and ii) a liquid phase. Partial condensation is reduced by adding a heated vaporous diluent, e.g., light hydrocarbon or superheated steam, to the flash/separation apparatus to an extent sufficient to at least partially compensate for the temperature decrease and to dilute and superheat the vapor phase, prior to removing the vapor phase as overhead for subsequent cracking and recovery of cracked product. An apparatus for carrying out the process 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: 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 method is disclosed for treating gaseous effluent from a hydrocarbon pyrolysis unit to provide steam cracked tar of reduced asphaltene and toluene insolubles content. The method is suitable for preparing reduced viscosity tar useful as a fuel blending stock, or feedstock for producing carbon black, while reducing or eliminating the need for externally sourced lighter aromatics additives to meet viscosity specifications. The method comprises drawing steam cracked tar from a separation vessel, e.g., a primary fractionator or tar knock-out drum, cooling the tar, and returning it to the separation vessel to effect lower overall tar temperatures within the separation vessel, in order to reduce viscosity increasing condensation reactions. An apparatus for carrying out the method is also provided.

Abstract: A process for cracking a hydrocarbon feedstock containing salt and/or particulate matter, wherein said hydrocarbon feedstock containing salt and/or particulate matter is partially desalted, e.g., by passing through a centrifugal separator, heated, then separated into a vapor phase and a liquid phase by flashing in a flash/separation vessel, separating and cracking the vapor phase which comprises less than about 98% of the hydrocarbon feedstock containing salt and/or particulate matter, and recovering cracked product.

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.

Abstract: A process is provided 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, optionally further heating the mixture, flashing the mixture within a flash/separation vessel to form a vapor phase and a liquid phase, partially condensing the vapor phase by contacting with a condenser within the vessel, to condense at least some coke precursors within the vapor while providing condensates which add to the liquid phase, removing the vapor phase of reduced coke precursors content as overhead and the liquid phase as bottoms, heating the vapor phase, cracking the vapor phase in a radiant section of a pyrolysis furnace to produce an effluent comprising olefins, and quenching the effluent and recovering cracked product therefrom. An apparatus for carrying out the process is also provided.

Abstract: An apparatus and process are provided for cracking hydrocarbonaceous feed, wherein the temperature of heated effluent directed to a vapor/liquid separator, e.g., flash drum, whose overhead is subsequently cracked, can be controlled within a range sufficient so the heated effluent is partially liquid, say, from about 260 to about 540° C. (500 to 1000° F.). This permits processing of a variety of feeds containing resid with greatly differing volatilities, e.g., atmospheric resid and crude at higher temperature and dirty liquid condensates, at lower temperatures. The temperature can be lowered as needed by: i) providing one or more additional downstream feed inlets to a convection section, ii) increasing the ratio of water/steam mixture added to the hydrocarbonaceous feed, iii) using a high pressure boiler feed water economizer to remove heat, iv) heating high pressure steam to remove heat, v) bypassing an intermediate portion of the convection section used, e.g.

Abstract: A vapor/liquid separation apparatus for treating a flow of vapor/liquid mixtures of hydrocarbons and steam comprises a vertical drum with a side inlet to introduce hydrocarbon/steam mixtures, an overhead vapor outlet, and a lower section in communication with a cylindrical boot of less diameter than the drum, the boot comprising sufficient gas-liquid contact surface, e.g., that provided by one or more sheds, baffles and/or distillation trays, to provide at least a partial theoretical distillation stage, and a lower portion for receiving liquid from the drum, a lower outlet for removing the liquid, and an inlet for introducing a stripping gas, such as steam, hydrogen, light crackable hydrocarbon, and/or methane, below the distillation tray and preferably above the level of liquid in the boot.

Abstract: A process for cracking a hydrocarbon feedstock containing salt and/or particulate matter, wherein said hydrocarbon feedstock containing salt and/or particulate matter is heated, then separated into a vapor phase and a liquid phase by flashing in a flash/separation vessel, separating and cracking the vapor phase which comprises less than about 98% of the hydrocarbon feedstock containing salt and/or particulate matter, and recovering cracked product. The salt and/or particulate matter are removed in the liquid bottoms stream from the flash/separation vessel.

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.

Abstract: Hydrocarbon feedstock containing resid is cracked by a process comprising: (a) heating the hydrocarbon feedstock; (b) mixing the heated hydrocarbon feedstock with steam and optionally water to form a mixture stream; (c) introducing the mixture stream to a flash/separation apparatus to form i) a vapor phase at its dew point which partially cracks and loses/or heat causing a temperature decrease and partial condensation of the vapor phase in the absence of added heat to provide coke precursors existing as uncoalesced condensate, and ii) a liquid phase; (d) removing the vapor phase as overhead and the liquid phase as bottoms from the flash/separation apparatus; (e) treating the overhead by contacting with a hydrocarbon-containing nucleating liquid substantially free of resid and comprising components boiling at a temperature of at least about 260° C. (500° F.