METHOD OF PREPARING PAVING ASPHALT Russian patent published in 2001 - IPC

FIELD: preparation of paving asphalt by vacuum distillation of black oils of sulfur and high- sulfur petroleum. SUBSTANCE: method comprises heating black oil, introducing it into vacuum column, taking cut light distillate, vacuum gas oil fractions and withdrawing stillage residue. Some light distillate is additionally heated and is used as evaporating agent which is introduced into vacuum column still. Stillage residue is mixed with plasticizer which is heavy vacuum gas oil. Mixture is then used as high-grade paving bitumen. EFFECT: more efficient preparation column. 1 dwg, 3 tbl