摘要 |
Process for the conversion to distillates of heavy feedstocks selected from heavy and extra-heavy crude oils, distillation residues from crude oil or from catalytic treatment, "visbreaking tars", "thermal tars", bitumens from "oil sands" liquids from coals of different origins and other high-boiling feedstocks of a hydrocarbon origin, known as "black oils", comprising the following steps: - sending the heavy feedstock to a first distillation zone (D1) having one or more atmospheric and/or vacuum distillation steps, whereby one or more light fractions are separated from the distillation residue; - sending the single light fraction or one or more light fractions coming from the first distillation zone (D1) to a hydrotreating (HT) zone wherein hydrogen is introduced; - sending the fraction consisting of the distillation residue of the first distillation zone (Dl) to a deasphalting zone (SDA) in the presence of solvents, obtaining two streams, one consisting of deasphalted oil (DAO), the other containing asphaltenes; - sending the effluent stream from the hydrotreatment (HT) zone to a second distillation zone (D2), consisting of one or more flash steps and/or one or more atmospheric distillation steps, through which the different fractions are separated, coming from the hydrotreatment of the distillation residue which is recycled to the first distillation zone (Dl) and/or to the deasphalting zone (SDA); - mixing of the stream consisting of deasphalted oil (DAO) with a suitable hydrogenation catalyst and sending the mixture obtained to a hydrocracking (HCK) zone in which hydrogen is added and from which the effluent stream is sent to the hydrotreatment (HT) zone and/or to the second distillation (D2) zone; - sending the stream containing asphaltenes to a gasification zone (POx) so as to obtain a mixture of H2 and CO; - sending the mixture of H2 and CO obtained in the gasification zone (POx) to a gas separation zone (GS) to recover the H2 to be used as reactive atmosphere for the hydrotreatment (HT) and hydrocracking (KCK) sections. |