Abstract: Vacuum distillation system which has a vacuum distillation column (1) having a column inlet (6), a bottom outlet (8) and a top outlet (10), a furnace (2) provided with a heat-exchange tube (27) having a tube inlet (28) and a tube outlet (29), and a connecting conduit (3) extending between the tube outlet (29) and the column inlet (6), wherein the inner diameter of the heat-exchange tube (27) increases along the length of the heat-exchange tube (27) to between 2.4 and three times the inner diameter of the tube inlet (28), and wherein the inner diameter of the connecting conduit (3) gradually increases along the length of the connecting conduit (3) to between 2.5 and 5.4 times the inner diameter of the tube outlet (29).

Abstract: An apparatus for fractional distillation under vacuum, comprising an evacuable vessel enclosing a first zone for liquid to be distilled, a second zone for distillate and a third zone for residue. The vessel is provided with a plurality of vertical tubular elements having side walls forming evaporator surfaces and being provided with inlet means at their upper ends for directing liquid to be distilled from the first zone towards the evaporator surface. Each hollow element surrounds at least partly a vertical cooling surface to cause condensation of vaporized liquid to form distillate, each hollow element being further provided with means for separately withdrawing distillate and residue from its interior into the second zone and the third zone, respectively. The vessel preferably consists of detachably interconnected wall portions.

Abstract: A process is disclosed for the conversion of asphaltines-containing mineral hydrocarbon oil to distillate gas oil by a processing sequence comprising thermal cracking, flashing, atmospheric fractionation, vacuum fractionation, thermal cracking, catalytic cracking or hydrocracking, and atmospheric fractionation with certain recycle of intermediate streams to achieve efficient, economic operations.

Abstract: A process for the preparation of gas oil from residual oils by combination of two stages of thermal cracking, cyclone separation, vacuum distillation, deasphalting, atmospheric distillation, and recycling of certain streams.

Abstract: A process is disclosed for catalytic hydrotreating of a heavy hydrocarbon oil and a light hydrocarbon oil in separate reactors, wherein the hydrotreating catalyst is circulated through both reactors. The process is particularly suited to obtaining long catalyst life when operating at low hydrogen pressures.