METHOD TO PRODUCE PETROL FRACTIONS Russian patent published in 2003 - IPC

FIELD: petroleum refining industry, raw oil stock rectification. SUBSTANCE: invention presents the method of fractionations of a raw oil stock and it may be used at production of factions of valuable petrol components from the one-run gasoline, for example, isopentanes and normal pentanes. Production of the petrol factions is exercised in two rectifying columns. The raw oil stock is fed to the first column. The stillage residue of the first column is introduced as a feeding supplies in the second rectifying column above the introduction level of the main supplies in it. The side outlet of the product fraction is located between inlets of feedings. The distillates from the top of the first and the second rectifying columns are removed as a product faction in the form of a blend of the low-boiling fractions. Preferably in capacity of a low- boiling product faction of gasoline they receive the isopentane faction. In an event of separation of petrol for "n" product fractions on grocery factions, the number of the side outlets is equal to "n-2" with location of these outlets l between inlets of the main and additional feeders. EFFECT: increased accuracy of separation at decrease of power costs. 3 cl, 2 tbl, 1 dwg