Increasing Tobacco Volume – Dry Ice Expanded Tobacco (DIET)

To achieve desired cigarette taste, quality and delivery properties, producers often expand tobacco’s cell structure utilizing the unique thermal-physical properties of carbon dioxide, a naturally occurring product of metabolism in plants and animals.

In a DIET process, tobacco and liquid carbon dioxide are combined in a pressurized tank. Through staged pressure release, carbon dioxide impregnated within the tobacco solidifies into dry ice, while excess liquid and gaseous carbon dioxide are recovered for reuse. When introduced to a stream of hot gas, impregnated tobacco rapidly expands to twice its volume. After cooling, expanded tobacco’s moisture content is reordered to an acceptable level.

Thayer Scale Equipment for Dry Ice Expanded Tobacco

Thayer Scale Low Density Model “M” Weigh Belts play an important role in optimizing volume expansion by accurately metering dry ice impregnated tobacco at a controlled rate into a rotary valve that introduces the tobacco to the hot end equipment of the DIET process.

To ensure reliable weigh belt operation while metering dry ice impregnated tobacco whose temperature of -436° F (-260° C), special polyolefin-filled spiral linked belting compounds and water-circulating pulleys are used.

In addition to increasing the filling power of cured tobacco, expanded tobacco:

  • Lowers the weight of tobacco per cigarette.
  • Reduces ISO tar and nicotine yields of the combustible tobacco.
  • Improves smoking quality by providing better airflow / drag characteristics.
  • Creates a firmer cigarette.

Weighing equipment for the processing of tobacco

Weighing equipment for the tobacco industry includes:

Weigh belts

  • Designed for light-density material handling in light loading applications (Model M-LD and MXL-LD)
  • Available with open or enclosed construction
  • Built to accommodate to new or existing process streams

Loss-in-weight feeders

  • Auger discharge
  • Vibratory pan discharge
  • Feed rates from grams/minute to tons/hour

Flexible conveyor belt scale designs that support changing configurations

Hopper and silo flow aids

  • Provides consistent, uninterrupted flow of material