Method for upgrading steam cracker tars

摘要

A process for the production of gaseous olefins which involves introducing a hydrocarbon feedstock stream into a high temperature thermal cracking zone to produce a high temperature cracked product stream, quenching the cracked product stream to stop the cracking reactions, injecting at least one HDD (hydrogen donor diluent) into the cracked product stream at or downstream of the point at which the reaction is quenched, recovering normally gaseous olefins from the cracked product stream, and recovering a liquid product stream containing a diminished asphaltene content.