METHOD FOR PRODUCING ROAD BITUMEN Russian patent published in 2021 - IPC C08L95/00 

FIELD: oil industry; construction industry; road construction.

SUBSTANCE: invention relates to a method for producing bitumen from propane deasphalting asphalt and can be used in the oil refining, road or construction industries. A method for producing road bitumen includes oxidizing a mixture of propane deasphalting asphalt with tar and residual extract. The initial mixture contains up to 60 wt. % of deasphalting asphalt as the main component, not less than 20 wt. % of tar and 20 wt. % of the residual extract as a liquefier. The initial mixture is divided into two streams, one of which enters the main reactor for the oxidation of raw materials with technical air, while the oxidation is carried out to a softening temperature of 70-75°C according to the ring-and-ball method. The other stream enters the separator-reactor for the oxidation of raw materials by off-gases from the main column reactor. In this case, the mixture obtained from the separator-reactor has a softening temperature up to 33°C according to the ring-and-ball method and contains up to 3 wt. % of slip stream - hydrocarbons condensed from gases in the above separator-reactor. Compounding of the obtained streams of oxidized raw materials from the main reactor and the separator-reactor in the mixer is carried out.

EFFECT: invention makes it possible to include up to 60% of propane deasphalting asphalt in bitumen raw materials, to reduce the concentration of air oxygen in exhaust gases, to utilize the slip stream using it as a plasticizing component of bitumen.

1 cl, 1 dwg, 1 tbl, 8 ex