FIELD: chemistry.
SUBSTANCE: invention relates to a method of converting a heavy hydrocarbon fraction with an initial boiling point higher than or equal to 340°C into a middle distillate with a boiling interval of 130 to 410°C. The present method employs a catalytic cracking apparatus combined with one or more oligomerisation apparatus, and raw material for the oligomerisation apparatus consists of a wide fraction containing 2-9 carbon atoms, obtained on the catalytic cracking apparatus, optionally hydrotreated on a hydrotreatment apparatus. Streams from the oligomerisation apparatus are divided into three fractions: a fraction, referred to as the raffinate, which corresponds to unreactive olefins and paraffins from the raw material of the oligomerisation apparatus, which can be fed into a gasoline pool, a fraction of light oligomers (15), having a boiling point lower than 180°C, preferably 150°C, which forms secondary raw material returned to the FCC apparatus, a fraction of heavy oligomers, having a boiling point higher than 130°C, preferably higher than 150°C, which is fed into the middle distillate obtained on the catalytic cracking apparatus.
EFFECT: improved distillate output and low gasoline output.
7 cl, 1 dwg, 7tbl, 3 ex
