semisoufflage

CONT: La technique de semi-soufflage relativement récente est actuellement largement employée. Elle consiste à souffler une base, obtenue par distillation atmosphérique ou sous vide, jusqu'à l'obtention d'un bitume défini.

CONT: Air-Rectification of Refinery Bitumen: Bitumen produced by straight steam-refining from certain crude oils may be deficient in the components of very high molecular weight which are insoluble in heptane, the ""asphaltene"" fraction ... It is the common practice of bitumen producers in the United Kingdom to increase the asphaltene content of low-asphaltene material by oxidation of the hot straight-run bitumen by a current of air blown through it. This process must not be confused with that used to produce the so-called ""blown"" grades of bitumen.
OBS: air-rectification: Possibly a term used only in Great Britain.