IMPROVED METHOD OF CONVERTING A HEAVY LOAD TO MEDIUM DISTILLATE USING UP-TO-THE-END PRETREATMENT OF THE CATALYTIC CRACKING UNIT

摘要

The present invention describes an improved process for converting a heavy feedstock that makes it possible to improve the selectivity for middle distillates. The invention consists in the implementation of a hydrotreatment or hydroconversion process, referred to as pretreatment process, of the heavy feedstock upstream of the assembly of a catalytic cracking unit followed by an oligomerization unit which makes it possible to increase the net production of C3, C4 and light petrol cuts at the end of the catalytic cracking unit and consequently to very significantly increase the production of middle distillates after the oligomerization step, and also the selectivity of middle distillates over petrol.