The invention concerns a process for converting a hydrocarbon feed, said process comprising the following steps: a) a step of hydrocracking the feed in the presence of hydrogen; b) a step of separating the effluent obtained from step a); c) a step of precipitating sediments, in which the heavy fraction obtained from the separation step b) is brought into contact with a distillate cut at least 20% by weight of which has a boiling point of 100° C. or more for a period of less than 500 minutes, at a temperature in the range 25° C. to 350° C., and at a pressure of less than 20 MPa; d) a step of physical separation of the sediments from the heavy fraction obtained from step c); e) a step of recovering a heavy fraction having a sediment content, measured using the ISO 10307-2 method, of 0.1% by weight or less.

The invention concerns a process for converting a hydrocarbon feed, said process comprising the following steps: a) a step of hydrocracking the feed in the presence of hydrogen; b) a step of separating the effluent obtained from step a); c) a step of precipitating sediments, in which the heavy fraction obtained from the separation step b) is brought into contact with a distillate cut at least 20% by weight of which has a boiling point of 100° C. or more for a period of less than 500 minutes, at a temperature in the range 25° C. to 350° C., and at a pressure of less than 20 MPa; d) a step of physical separation of the sediments from the heavy fraction obtained from step c); e) a step of recovering a heavy fraction having a sediment content, measured using the ISO 10307-2 method, of 0.1% by weight or less.

A process and system for treating a hydroprocessing unit effluent gas stream for recycling includes introducing the effluent gas stream into a hydrogen purification zone and recovering a hydrogen-rich gas stream and a liquid stream containing a mixture that includes C1 to C4 hydrocarbons and H.sub.2S which is then mixed with an oxidant and fed to an oxidation unit containing catalyst for conversion of the H.sub.2S to elemental sulfur vapors that is separated for recovery of the elemental sulfur, and recovering a sweetened mixture that includes C1 to C4 hydrocarbons. Alternatively, the hydroprocessing unit effluent gas stream containing H.sub.2S is cooled, contacted with a solvent to absorb the C1 to C4 hydrocarbons and H.sub.2S, with the hydrogen-rich stream being recovered for recycling to the hydroprocessing unit, and the rich liquid solvent being flashed to produce a lean solvent stream for recycling to the adsorption zone and a mixed gas stream that includes the C1 to C4 hydrocarbons and H.sub.2S that is passed to an oxidation zone and is reacted with an oxidant in the presence of a catalyst to complete the process as described above for the recovery of elemental sulfur and a mixture that includes the sweetened C1 to C4 hydrocarbons.

A process and system for treating a hydroprocessing unit effluent gas stream for recycling includes introducing the effluent gas stream into a hydrogen purification zone and recovering a hydrogen-rich gas stream and a liquid stream containing a mixture that includes C1 to C4 hydrocarbons and H.sub.2S which is then mixed with an oxidant and fed to an oxidation unit containing catalyst for conversion of the H.sub.2S to elemental sulfur vapors that is separated for recovery of the elemental sulfur, and recovering a sweetened mixture that includes C1 to C4 hydrocarbons. Alternatively, the hydroprocessing unit effluent gas stream containing H.sub.2S is cooled, contacted with a solvent to absorb the C1 to C4 hydrocarbons and H.sub.2S, with the hydrogen-rich stream being recovered for recycling to the hydroprocessing unit, and the rich liquid solvent being flashed to produce a lean solvent stream for recycling to the adsorption zone and a mixed gas stream that includes the C1 to C4 hydrocarbons and H.sub.2S that is passed to an oxidation zone and is reacted with an oxidant in the presence of a catalyst to complete the process as described above for the recovery of elemental sulfur and a mixture that includes the sweetened C1 to C4 hydrocarbons.

A process for the treatment of sulfidic spent caustic, conditioned catalyst regeneration vent gas, C4 isomerization off gas, various and hydrocarbon containing liquid and gaseous streams in addition to toxic containing streams like cyanidic off gas and waste water in a propane/butane dehydrogenation complex is described. Various effluent streams are combined in appropriate collection vessels, including an off-gas knockout drum, a hydrocarbon buffer vessel, a spent caustic buffer vessel, an optional a waste water buffer vessel, and a fuel gas knockout drum. Streams from these vessels are sent to a thermal oxidation system.

A process for the treatment of sulfidic spent caustic, conditioned catalyst regeneration vent gas, C4 isomerization off gas, various and hydrocarbon containing liquid and gaseous streams in addition to toxic containing streams like cyanidic off gas and waste water in a propane/butane dehydrogenation complex is described. Various effluent streams are combined in appropriate collection vessels, including an off-gas knockout drum, a hydrocarbon buffer vessel, a spent caustic buffer vessel, an optional a waste water buffer vessel, and a fuel gas knockout drum. Streams from these vessels are sent to a thermal oxidation system.

A heavy petroleum oil feed is upgraded by having its amenability to cracking improved by subjecting the oil to selective partial oxidation with a catalytic oxidation system to partially oxidize aromatic ring systems in the heavy oil. The partially oxidized oil can then be cracked in the conventional manner but at lower severities to lower molecular weight cracking products. The cracking following the partial oxidation step may be thermal in nature as by thermal cracking, delayed, contact or fluid coking or fluid catalytic cracking or hydrogenative as in hydrocracking.

A heavy petroleum oil feed is upgraded by having its amenability to cracking improved by subjecting the oil to selective partial oxidation with a catalytic oxidation system to partially oxidize aromatic ring systems in the heavy oil. The partially oxidized oil can then be cracked in the conventional manner but at lower severities to lower molecular weight cracking products. The cracking following the partial oxidation step may be thermal in nature as by thermal cracking, delayed, contact or fluid coking or fluid catalytic cracking or hydrogenative as in hydrocracking.

The invention relates to systems and methods for ultrasonic oxidative desulfurization of heavy fuel oils. In various embodiments, the methods include combinations of ultrasonic sulfone decomposition processes and/or catalytic decomposition processes.

The invention relates to systems and methods for ultrasonic oxidative desulfurization of heavy fuel oils. In various embodiments, the methods include combinations of ultrasonic sulfone decomposition processes and/or catalytic decomposition processes.