METHOD OF PRELIMINARY DISTILLATION OF OIL Russian patent published in 1999 - IPC

FIELD: oil refining at plants AT and ABT with two-column system of oil distillation at atmospheric pressure. SUBSTANCE: preliminary distillation of oil is carried out in two atmospheric columns with obtaining unstable rectificate and withdrawal from semiclosed tray in reinforcing section of the first column of side-cut distillate which is supplied to the second column, to zone between outlets of rectificate and the first (or second) side-cut distillate. Preferably, side-cut distillate is withdrawn from level of the first column in which temperature of end of boiling of bottoms corresponds to temperature of boiling end of side-cut distillate of the second column. Side-cut distillate of the first column is supplied above outlet of the side-cut distillate of the second column. EFFECT: reduced energy consumption for oil distillation, higher withdrawal of sum of light oil products with increased difference of their separation. 3 cl, 1 dwg, 1 tbl