Process for dehydration and/or desalination and for simultaneous fractionation of a petroleum deposit effluent

摘要

A process for the dehydration and/or desalination and simultaneous fractionation of a petroleum deposit effluent containing oil, associated gas and water which can be saline, which process comprises:P P(a) at least one step for separating the liquid and gaseous phases at the pressure P1 for removal of the gas, producing a gaseous fraction G1, on the one hand, which is removed and a liquid fraction L1, on the other hand, which is sent to stepP P(b) at least one step for separating, at least partly, the two liquid phases mixed in the liquid fraction L1, the aqueous phase being partly removed and the oil phase containing a quantity of residual aqueous phase being sent to step (c);PP(c) at least one distillation step carried out at a pressure P2 which is less than, or at the most equal to, the pressure P1 in step (a), in a distillation zone C1, said distillation being carried out in the presence of the oil phase coming from step (b), said zone C1 comprising an internal heat exchange zone and a boiling zone, and enabling a gaseous fraction G2, on the one hand, and a liquid fraction L2, on the other hand, to be recovered, said fraction L2 being constituted by a liquid oil phase and an aqueous liquid phase which is not miscible with the liquid oil phase; andP P(d) at least one step for separating the two liquid phases mixed in the liquid fraction L2, the oil phase being sent into said internal exchange zone, and then removed.