METHOD OF PRODUCING RECTIFIED ALCOHOL Russian patent published in 1997 - IPC

FIELD: alcohol industry. SUBSTANCE: alcohol is digested from brew in brew-epuration column accompanied by transferring ethyl alcohol with impurities into brew distillate with vapor effluent from this column. Brew distillate is purified from head and intermediate impurities, including fusel oil components, in epuration column involving hydroselection operation. Epurate is rectified in alcohol column to yield fusel oil fractions, fusel alcohol, and non-pasteurized ethyl alcohol. Ethyl alcohol is additionally purified by way of removing fusel-ester-aldehyde-methanol fractions from carbon dioxide separator condenser and methanol-ester- aldehyde fraction from condenser and alcohol trap of closed column which is fed and heated by vapors of brew distillate from brew epuration column. Epuration of brew distillate is carried out in epuration column into which hot water is supplied onto upper tray and condensate of fusel-ester-aldehyde-methanol fraction is tapped out of condenser. The latter fraction, together with fractions from condensers of closed, methanol, alcohol, concentration column, carbon dioxide separator, and alcohol trap are fed onto feed tray of distillation column, digestion part of which is separated by hollow insertion into two zones. Upper zone serves to digest methanol, esters, aldehydes, and other head impurities from ethyl alcohol, which are concentrated in concentration part of distillation column and its dephlegmator, whereupon head fraction concentrate is withdrawn from condenser. In lower zone, fusel oil components and other impurities are digested from ethyl alcohol and are tapped out of hollow insertion with steam which is used to feed and heat concentration column with accumulator sheet-steel drum in the middle zone, into which column hot water is fed. From sheet-steel drum, fusel oil is withdrawn, whereas concentrate of propyl alcohols is withdrawn from liquid phase collected on tray over the insertion; and impurity-free water-alcohol liquid is withdrawn from the still and returned into brew. Final removal of methanol, esters, aldehydes, and other head impurities from rectified alcohol is effected in methanol column which is heated by means of external boiler with epurated water-alcohol vapors from brew epuration column, whose condensate is directed into middle zone of digestion column. EFFECT: improved process flowsheet. 1 tbl