Systems and methods are provided for co-processing of pyrolysis tar with pre-pyrolysis flash bottoms. In some aspects, the co-processing can correspond to solvent-assisted hydroprocessing. By combining pyrolysis tar and flash bottoms with a solvent, various difficulties associated with hydroprocessing of the fractions can be reduced or minimized, such as difficulties associated with hydroprocessing of high viscosity feeds and/or high sulfur feeds. Optionally, separate solvents and/or fluxes can be used for the pyrolysis tar and the flash bottoms. The resulting upgraded products can be suitable, for example, for inclusion in low sulfur fuel oils (LSFO).

A method of removing oxygenates from a hydrocarbon stream comprises passing a hydrocarbon stream to a caustic tower having a plurality of loops, contacting the hydrocarbon stream with a sulfided catalyst between a first loop of the plurality of loops and a second loop of the plurality of loops to produce a reaction product, passing the reaction product to the second loop, removing at least a portion of the hydrogen sulfide in the second loop of the caustic tower to produce a product stream, and separating the product stream into a plurality of hydrocarbon streams in a separation zone located downstream of the caustic tower. The hydrocarbon stream comprises hydrocarbons, oxygen containing components, and sulfur containing compounds. At least a portion of the sulfur compounds react in the presence of the sulfided catalyst to produce hydrogen sulfide in the reaction product.

The invention relates to a method for refining a feed oil having contaminants therein. In the method, the feed oil is exposed to reducing conditions at elevated temperature and pressure so as to reduce at least some of said contaminants. The resulting oil is then degassed under reduced pressure under non-oxidizing conditions and the resulting oil extracted with water so as to produce a refined oil.

The invention relates to a method for refining a feed oil having contaminants therein. In the method, the feed oil is exposed to reducing conditions at elevated temperature and pressure so as to reduce at least some of said contaminants. The resulting oil is then degassed under reduced pressure under non-oxidizing conditions and the resulting oil extracted with water so as to produce a refined oil.

Naphthenic process oils are made by blending one or more naphthenic vacuum gas oils in one or more viscosity ranges with a high C.sub.A content distilled aromatic extract feedstock to provide at least one blended oil, and hydrotreating the at least one blended oil to provide an enhanced C.sub.A content naphthenic process oil. The order of the vacuum distillation and blending steps may be reversed.

Naphthenic process oils are made by blending one or more naphthenic vacuum gas oils in one or more viscosity ranges with a high C.sub.A content distilled aromatic extract feedstock to provide at least one blended oil, and hydrotreating the at least one blended oil to provide an enhanced C.sub.A content naphthenic process oil. The order of the vacuum distillation and blending steps may be reversed.

A system for processing a stream including fuel oil includes an atmospheric flash column for receiving the stream as feedstock and separate the stream into an atmospheric flash distillate stream and an atmospheric flash residue stream. The system includes a vacuum flash column for receiving the atmospheric flash residue stream and separating the atmospheric flash residue stream into a vacuum flash distillate stream, a vacuum flash residue stream, and a vacuum gas oil stream. The system includes a first hydrocracking unit for receiving and processing at least a portion of the vacuum flash residue stream to produce an intermediate stream and a slurry. The system includes a second hydrocracking unit for receiving and processing the vacuum gas oil stream and the intermediate stream to produce a naphtha product and a light ends product. The system includes a pelletization unit for receiving and processing the slurry to produce a pelletized product.

A system for processing a stream including fuel oil includes an atmospheric flash column for receiving the stream as feedstock and separate the stream into an atmospheric flash distillate stream and an atmospheric flash residue stream. The system includes a vacuum flash column for receiving the atmospheric flash residue stream and separating the atmospheric flash residue stream into a vacuum flash distillate stream, a vacuum flash residue stream, and a vacuum gas oil stream. The system includes a first hydrocracking unit for receiving and processing at least a portion of the vacuum flash residue stream to produce an intermediate stream and a slurry. The system includes a second hydrocracking unit for receiving and processing the vacuum gas oil stream and the intermediate stream to produce a naphtha product and a light ends product. The system includes a pelletization unit for receiving and processing the slurry to produce a pelletized product.

The invention pertains to a method for processing a Fischer-Tropsch off-gas wherein Fischer-Tropsch off-gas is contacted with a wash fluid in a scrubber, and wherein the wash fluid is recycled in a closed loop with a dedicated scrubber, stripper and splitter. The wash fluid preferably is kerosene or LDF. The C.sub.3+ hydrocarbons that are recovered from the off-gas are, together with other Fischer-Tropsch product, subjected to hydrocracking or hydrocracking/hydroisomerization. Additionally, hydrogen is recovered from the off-gas.

The invention pertains to a method for processing a Fischer-Tropsch off-gas wherein Fischer-Tropsch off-gas is contacted with a wash fluid in a scrubber, and wherein the wash fluid is recycled in a closed loop with a dedicated scrubber, stripper and splitter. The wash fluid preferably is kerosene or LDF. The C.sub.3+ hydrocarbons that are recovered from the off-gas are, together with other Fischer-Tropsch product, subjected to hydrocracking or hydrocracking/hydroisomerization. Additionally, hydrogen is recovered from the off-gas.