The invention relates to an improved system and method for relief of hot, high pressure, fouling fluid from the 1.sup.st Stage Reactor and the ISS in case of an unintended overpressure situation while allowing the quick establishing of normal fluid flow path once the overpressure situation has been corrected. This allows for rapid cooling of all subsequent reactor stages while minimizing VGO slop generation that needs reprocessing.

A moving bed reactor is provided that can allow facilitate performing a reaction involving a three-phase flow under co-axial flow conditions for the solid and liquid portions of the three phase flow, while the gas portion of the three-phase flow is exposed to the solids under radial flow conditions. Methods for using such a moving bed reactor to perform a reaction, such as upgrading of a feed to distillate products, are also provided.

A moving bed reactor is provided that can allow facilitate performing a reaction involving a three-phase flow under co-axial flow conditions for the solid and liquid portions of the three phase flow, while the gas portion of the three-phase flow is exposed to the solids under radial flow conditions. Methods for using such a moving bed reactor to perform a reaction, such as upgrading of a feed to distillate products, are also provided.

An integrated hydrotreating and hydrocracking process includes contacting a hydrocarbon oil stream with a hydrogen stream and a hydrotreating catalyst in a moving-bed hydrotreating reactor, thereby producing a hydrocarbon product stream and a spent hydrotreating catalyst; contacting the hydrocarbon product stream with a second hydrogen stream and a hydrocracking catalyst in a hydrocracking reactor, thereby producing a hydrocracked hydrocarbon product stream; processing the spent hydrotreating catalyst to produce regenerated hydrotreating catalyst; and recycling the regenerated hydrotreating catalyst to the moving-bed hydrotreating reactor.

An integrated hydrotreating and hydrocracking process includes contacting a hydrocarbon oil stream with a hydrogen stream and a hydrotreating catalyst in a moving-bed hydrotreating reactor, thereby producing a hydrocarbon product stream and a spent hydrotreating catalyst; contacting the hydrocarbon product stream with a second hydrogen stream and a hydrocracking catalyst in a hydrocracking reactor, thereby producing a hydrocracked hydrocarbon product stream; processing the spent hydrotreating catalyst to produce regenerated hydrotreating catalyst; and recycling the regenerated hydrotreating catalyst to the moving-bed hydrotreating reactor.

A process for treatment of PFO from a steam cracking zone includes selectively hydrogenating PFO or a portion thereof for conversion of polyaromatics compounds contained in the PFO into aromatic compounds with one benzene ring to produce a selectively hydrogenated stream. The selectively hydrogenated stream is reacted in a fluid catalytic cracking reactor for selective ring opening and dealkylation to produce fluid catalytic cracking including light cycle oil. The light cycle oil is separated into BTX compounds. Optionally the PFO is separated into a first stream containing C9+ aromatics compounds with one benzene ring, and a second stream containing C10+ aromatic compounds, whereby the first stream containing C9+ aromatics compounds with one benzene ring is passed to the fluid catalytic cracking reactor, and the feed to the selective hydrogenation step comprises all or a portion of the second stream containing C10+ aromatic compounds.

A process for treatment of PFO from a steam cracking zone includes selectively hydrogenating PFO or a portion thereof for conversion of polyaromatics compounds contained in the PFO into aromatic compounds with one benzene ring to produce a selectively hydrogenated stream. The selectively hydrogenated stream is reacted in a fluid catalytic cracking reactor for selective ring opening and dealkylation to produce fluid catalytic cracking including light cycle oil. The light cycle oil is separated into BTX compounds. Optionally the PFO is separated into a first stream containing C9+ aromatics compounds with one benzene ring, and a second stream containing C10+ aromatic compounds, whereby the first stream containing C9+ aromatics compounds with one benzene ring is passed to the fluid catalytic cracking reactor, and the feed to the selective hydrogenation step comprises all or a portion of the second stream containing C10+ aromatic compounds.

A process for conversion of a liquid hydrocarbon feedstock in a moving bed hydroprocessing reactor is provided in which (a) hydrogen gas is dissolved in the liquid feedstock and (b) the mixture is flashed to remove and recover any light components, leaving a hydrogen-enriched feedstock. A homogeneous and/or heterogeneous catalyst is added to the feedstock upstream of the moving bed hydroprocessing rector.

A process for treatment of PFO from a steam cracking zone includes selectively hydrogenating PFO or a portion thereof for conversion of polyaromatics compounds contained in the PFO into aromatic compounds with one benzene ring to produce a selectively hydrogenated stream. The selectively hydrogenated stream is reacted in a fluid catalytic cracking reactor for selective ring opening and dealkylation to produce fluid catalytic cracking including light cycle oil. The light cycle oil is separated into BTX compounds. Optionally the PFO is separated into a first stream containing C9+ aromatics compounds with one benzene ring, and a second stream containing C10+ aromatic compounds, whereby the first stream containing C9+ aromatics compounds with one benzene ring is passed to the fluid catalytic cracking reactor, and the feed to the selective hydrogenation step comprises all or a portion of the second stream containing C10+ aromatic compounds.

A process for treatment of PFO from a steam cracking zone includes selectively hydrogenating PFO or a portion thereof for conversion of polyaromatics compounds contained in the PFO into aromatic compounds with one benzene ring to produce a selectively hydrogenated stream. The selectively hydrogenated stream is reacted in a fluid catalytic cracking reactor for selective ring opening and dealkylation to produce fluid catalytic cracking including light cycle oil. The light cycle oil is separated into BTX compounds. Optionally the PFO is separated into a first stream containing C9+ aromatics compounds with one benzene ring, and a second stream containing C10+ aromatic compounds, whereby the first stream containing C9+ aromatics compounds with one benzene ring is passed to the fluid catalytic cracking reactor, and the feed to the selective hydrogenation step comprises all or a portion of the second stream containing C10+ aromatic compounds.