| 摘要 |
<p>Process for the conversion of heavy feedstocks comprising the following steps: mixing the heavy feedstock with a suitable hydrogenation catalyst and sending the mixture obtained to a first hydrotreatment area (HT1) to which hydrogen or a mixture of hydrogen and H2S are introduced; sending the effluent stream from the first hydrotreatment area (HT1), containing the hydrotreatment reaction product and the catalyst in dispersed phase, to a first distillation area (D1) having one or more flash steps and/or atmospheric distillation and/or vacuum distillation whereby the various fractions coming from the hydrotreatment reaction are separated; sending at least part of the distillation residue (tar) or liquid leaving the flash unit of the first distillation area (D1), containing the catalyst in dispersed phase, rich in metalic sulfides produced by demetallation of the feedstock and optionally minimum quantities of coke, to a deasphalting area (SDA) in the presence of solvents or to a physical separation area, obtaining, in the case of the deasphalting area, two streams, one consisting of deasphalted oil (DAO), the other containing asphaltenes at least partially recycled to the first hydrotreatment area, in the case of the physical separation area, the solids separated and a liquid stream; sending the stream consisting of deasphalted oil (DAO) or the liquid stream separated in the physical separation area to a second hydrotreatment area (HT2), to which hydrogen or a mixture of hydrogen and H2S and a suitable hydrogenation catalyst are introduced; sending the effluent stream from the second hydrotreatment area (HT2), containing the hydrotreatment reaction product and the catalyst in dispersed phase, to a second distillation area (D2) having one or more flash and/or distillation steps whereby the various fractions coming from the second hydrotreatment area are separated; recycling at least part of the distillation residue or liquid leaving the flash unit of the second distillation area (D2), containing the catalyst in dispersed phase to the second hydrotreatment area (HT2).</p> |
