Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems are described that can use feedstock materials, such as cellulosic and/or lignocellulosic materials, to produce ethanol and/or butanol, e.g., by fermentation.

A process for the refining of crude oil, comprising a separation unit of the crude oil, consisting of at least one atmospheric distillation unit for separating the various fractions, a unit for the conversion of the heavy fractions obtained, a unit for improving the quality of some of the fractions obtained by actions on the chemical composition of their constituents, and units for the removal of undesired components, characterized in that the heaviest fraction, the atmospheric distillation residue, is sent to the conversion unit comprising a hydroconversion reactor in slurry phase or of the ebullated bed type, into which hydrogen or a mixture of hydrogen and S is introduced in the presence of a suitable nanodispersed hydrogenation catalyst.

A process for the refining of crude oil, comprising a separation unit of the crude oil, consisting of at least one atmospheric distillation unit for separating the various fractions, a unit for the conversion of the heavy fractions obtained, a unit for improving the quality of some of the fractions obtained by actions on the chemical composition of their constituents, and units for the removal of undesired components, characterized in that the heaviest fraction, the atmospheric distillation residue, is sent to the conversion unit comprising a hydroconversion reactor in slurry phase or of the ebullated bed type, into which hydrogen or a mixture of hydrogen and S is introduced in the presence of a suitable nanodispersed hydrogenation catalyst.

Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems are described that can use feedstock materials, such as cellulosic and/or lignocellulosic materials, to produce ethanol and/or butanol, e.g., by fermentation.

Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems are described that can use feedstock materials, such as cellulosic and/or lignocellulosic materials, to produce ethanol and/or butanol, e.g., by fermentation.

Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems are described that can use feedstock materials, such as cellulosic and/or lignocellulosic materials, to produce ethanol and/or butanol, e.g., by fermentation.

A system and method for preparing and conditioning a heavy oil feedstock for hydroprocessing in a hydroprocessing system includes forming metal sulfide catalyst particles in situ within the heavy oil feedstock. The metal sulfide catalyst particles are formed in situ by (1) premixing a catalyst precursor with a hydrocarbon diluent to form a diluted precursor mixture, (2) mixing the diluted precursor mixture with the heavy oil feedstock to form a conditioned feedstock, and (3) heating the conditioned feedstock to decompose the catalyst precursor and cause or allow metal from the precursor to react with sulfur in the heavy oil feedstock to form metal sulfide catalyst particles in situ in the heavy oil feedstock. The in situ formed metal sulfide catalyst particles catalyze beneficial upgrading reactions between the heavy oil feedstock and hydrogen and eliminates or reduces formation of coke precursors and sediment.

A system and method for preparing and conditioning a heavy oil feedstock for hydroprocessing in a hydroprocessing system includes forming metal sulfide catalyst particles in situ within the heavy oil feedstock. The metal sulfide catalyst particles are formed in situ by (1) premixing a catalyst precursor with a hydrocarbon diluent to form a diluted precursor mixture, (2) mixing the diluted precursor mixture with the heavy oil feedstock to form a conditioned feedstock, and (3) heating the conditioned feedstock to decompose the catalyst precursor and cause or allow metal from the precursor to react with sulfur in the heavy oil feedstock to form metal sulfide catalyst particles in situ in the heavy oil feedstock. The in situ formed metal sulfide catalyst particles catalyze beneficial upgrading reactions between the heavy oil feedstock and hydrogen and eliminates or reduces formation of coke precursors and sediment.

An ebullated bed hydroprocessing system is upgraded using a dual catalyst system that includes a heterogeneous catalyst and dispersed metal sulfide particles to produce less fouling sediment. The dual catalyst system more effectively converts sediment-forming precursors to produce sediment that is less fouling than sediment produced using only the heterogeneous catalyst and not the dispersed metal sulfide particles. The dual catalyst system provides for a lower rate of equipment fouling for a given sediment production rate and/or concentration. In some cases, sediment production rate and/or concentration can be maintained or increased while equipment fouling is reduced. In some cases, sediment production rate and/or concentration can be increased without increasing equipment fouling.

A method is provided of shutting down an operating three-phase slurry bubble column reactor (10) having downwardly directed gas distribution nozzles (30) submerged in a slurry body (19) of solid particulate material suspended in a suspension liquid contained inside a reactor vessel (12), with the gas distribution nozzles (30) being in flow communication with a gas feed line (26) through which gas is fed to the gas distribution nozzles (30) by means of which the gas is injected downwardly into the slurry body (19). The method includes abruptly stopping flow of gas from the gas feed line (26) to the gas distribution nozzles (30) to trap gas in the gas distribution nozzles (30) thereby to inhibit slurry ingress upwardly into the gas distribution nozzles (30).