Abstract: This invention relates broadly to an improved process for expanding tobacco and involves certain modifications of the basic process for expanding tobacco comprising the steps of (1) contacting the tobacco with liquid carbon dioxide to impregnate the tobacco with the liquid carbon dioxide, (2) subjecting the liquid carbon dioxide-impregnated tobacco to conditions such that the liquid carbon dioxide is converted to solid carbon dioxide and (3) thereafter subjecting the solid carbon dioxide-containing tobacco to conditions whereby the solid carbon dioxide is vaporized to cause expansion of the tobacco. The present invention pertains, in one embodiment, to an improvement in the basic process which involves controlling the moisture content of the tobacco which is employed in the first step of the basic process.

Abstract: A substantially horizontal grating having a plurality of substantially parallel bars extends within an enclosure that is adapted to gravitationally receive a mass of tobacco containing a cryogen and discharge smaller tobacco particles therefrom. A plurality of rotatable shafts having a plurality of blades equally separated by spacers are disposed orthogonally over the parallel bars such that the blades are located between the parallel bars. The spacers on the shafts and the parallel bars cooperate to define a plurality of sized apertures through the grating. The blades are formed to separate portions of the mass upon rotation and to urge the portions through the sized apertures for discharge from the apparatus.

Abstract: This invention relates broadly to an improved process for expanding tobacco and involves certain modifications of the basic process for expanding tobacco comprising the steps of (1) contacting the tobacco with liquid carbon dioxide to impregnate the tobacco with the liquid carbon dioxide, (2) subjecting the liquid carbon dioxide-impregnated tobacco to conditions such that the liquid carbon dioxide is converted to solid carbon dioxide and (3) thereafter subjecting the solid carbon dioxide-containing tobacco to conditions whereby the solid carbon dioxide is vaporized to cause expansion of the tobacco. The present invention pertains, in one embodiment, to an improvement in the basic process which involves controlling the moisture content of the tobacco which is employed in the first step of the basic process.