Steam cracking processes and the use of solvents streams produced by solvent-assisted tar conversion processes

A method for decreasing reactor fouling in a steam cracking process comprising:

• steam cracking a hydrocarbon feed to obtain a quench oil composition comprising a concentration of donatable hydrogen of 0.5 wt. % or more based on a total weight percent of the quench oil composition;
• adding the quench oil composition to a steam cracker effluent flowing from a pyrolysis furnace to form a mixture;
• separating a steam cracker tar from the mixture;
• hydroprocessing at least a portion of the separated steam cracker tar in a first hydroprocessing zone under catalytic hydroprocessing conditions to convert at least a portion of the separated steam cracker tar to a first hydroprocessed product;
• separating from the first hydroprocessed product one or more of:
• (i) an overhead stream comprising ≥about 1.0 wt. % of the first hydroprocessed product;
• (ii) a mid-cut stream comprising ≥about 20 wt. % of the first hydroprocessed product;
• and
• (iii) a bottoms stream comprising ≥about 20 wt. % of the first hydroprocessed product;
• wherein the quench oil includes one or more of at least a portion of the overhead stream, at least a portion of the mid-cut stream, and at least a portion of the bottoms stream;
• and
• hydroprocessing at least a portion of the bottoms stream in a second hydroprocessing zone under second catalytic hydroprocessing conditions to convert at least a portion of the bottoms stream to a second hydroprocessed product, wherein the second hydroprocessed product has a sulfur content of 1.5 wt. % or less based on the total weight of the second hydroprocessed product.