Upgrading hydrocarbon pyrolysis products

摘要

The invention relates to a process for upgrading pyrolysis tar, such as steam cracker tar, in the presence of a utility fluid. The utility fluid contains 2-ring and/or 3-ring aromatics and has solubility blending number (SBN)≧120. The invention also relates to the upgraded pyrolysis tar and to the use of the upgraded pyrolysis tar, for example, for fuel oil blending.

主权项

1. A hydrocarbon conversion process, comprising:
(a) providing a pyrolysis feedstock comprising ≧10.0 wt. % hydrocarbon based on the weight of the pyrolysis feedstock; (b) pyrolysing the pyrolysis feedstock to produce a pyrolysis effluent comprising pyrolysis tar and ≧1.0 wt. % of C2 unsaturates, based on the weight of the pyrolysis effluent; (c) separating at least a portion of the pyrolysis tar from the pyrolysis effluent, wherein the separated pyrolysis tar has IN>110 and ≧90 wt. % of the pyrolysis effluent's molecules have an atmospheric boiling point of ≧290° C.; (d) providing a utility fluid, the utility fluid comprising ring aromatics, in an amount ≧25.0 wt. % based on the weight of the utility fluid, and the utility fluid having SBN≧120; (e) combining at least a portion of the separated pyrolysis tar and utility fluid; (f) providing treat gas comprising molecular hydrogen; (g) hydroprocessing the combined pyrolysis tar and utility fluid in a hydroprocessing zone in the presence of treat gas under catalytic hydroprocessing conditions to produce hydroprocessed effluent, comprising hydroprocessed tar; (h) separating from the hydroprocessed effluent a bottoms stream and a first vapor stream; (i) separating from the first vapor stream a mid-cut stream and a second vapor stream; (j) separating from the second vapor stream a light liquid overhead stream and a total vapor product; (k) combining at least a portion of the mid-cut stream with at least a portion of the bottoms stream to form a heavy mid-cut stream, the heavy mid-cut stream having SBN≧120; and (l) conducting at least a portion of the heavy mid-cut stream to step (d), wherein the utility fluid comprises ≧10.0 wt. % of the heavy mid-cut stream, based on the weight of the utility fluid.