GB411234A - Process and apparatus for the fractional distillation of crude petroleums, their derivatives and the like - Google Patents

Abstract

<PICT:0411234/III/1> <PICT:0411234/III/2> <PICT:0411234/III/3> Crude oil is distilled to obtain lubricating oi by preheating the oil under vacuum while ascending in gyratory motion in a thin layer and then vaporizing it in films and in a state of turbulence while descending with sustained gyratory motion over an undulated, corrugated, or like uneven surface of revolution in countercurrent to the vapours evolved so that vaporization takes place without splashing, emulsification or frothing. The oil is pumped from a tank WO through a pipe w1 to an annular heater HW surrounding the upper portion of a steam jacket J itself surrounding a column TC filled with Raschig rings. The oil flows out of the top of the heater through a pipe w2 into the bottom of the column TC1 up which it flows in counterflow to a washing solution, e.g. caustic soda pumped from a tank CS1 and heated to 65 DEG C. in a jacket H5, before entering the column through a pipe c2, from which it is returned charged with impurities to the tank CS1 through a pipe slo. The purified oil is passed through a pipe w4 into a second similar column TC2 in which it is again treated with chemicals and washing water from a jacket HW1. The upper part of the column is separated by a partition R from chambers F, TV, into which the oil now raised to boiling point enters through pipes w7, w8. The oil flows up the chamber TV where it is heated by the jacket J2 and the vapours evolved pass off through a pipe GO to a condenser GG while the residual oil overflows over the toothed edge Fd of the top of the column TC2 and falls in films down the inside passing off by a pipe w9. The oil is then passed into a flash vaporizer FV up which it flows in an annular jacket M1 and is then distributed over a gallery DS so that it flows in films down the undulated inner side of a conical vessel FC heated by a jacket J3. The vapours evolved pass off to a battery of dephlegmators D1, D2, D3 cooled by air and liquid from which condensate is collected and passed through cooling tanks Sh, Sm, Sl, to tanks A3, A4, A5. The jacket J3 is heated by diphenyl &c., circulated through cylindrical casings m, m1, m2 of a heater CH the waste gases from which are used to generate in a generator SG the steam required for the process. The level of the spent washing solution at the bottom of the column TC1 is controlled by a float FC1 automatically operating a drain valve 4. Vapours passing through the dephlegmators are finally condensed in a condenser KC maintained under vacuum by a three stage pump VP3. The condensers GG and KC, Fig. 4 comprise each concentric tubes 31, 32, 33, 34. The inmost tube 34 serves for the passage of cooling air while the tubes open out at the top to form headers 35, 36 to which the vapours to be condensed are supplied tangentially through pipes 37<1> of a manifold 37, and a header 38<1> from which cooling water, supplied from a pipe 38 to the annular space between the tubes 32, 33, is led off through a pipe 39. The condensate is led off to a separator Sg.