SCW Incorporated, a North Carolina-based company devoted to the development of new products and processes for the tobacco industry, announced the development of a new low-cost tobacco expansion processing, which employs conventional equipment and process conditions but incorporates a new two-step impregnation system

According to co-inventor John Wagner, porosity measurements showed that only a very small proportion of the volume within tobacco (about 8 per cent) can effectively contribute to expansion. The project’s aim was to find a way to penetrate this critical area with an acceptable expansion agent. Experimentation revealed that removing the fixed gases under vacuum, followed by the addition of a small amount of absolute ethanol, coated the interior surface of the tobacco. This allowed the tobacco to absorb a hydrocarbon propellant into the pores as the system was returned to atmospheric pressure. The combination of hydrocarbon and alcohol has the advantage of a lower boiling temperature than either component alone.
SCW is presently designing a 2500 kg/h production prototype of the new system.