A process for increasing the filling capacity of tobacco

Claim 2

The process of claim 1 in which the expanded tobacco is separated from said gas and vapors.

Claim 3

The process of claim 1 in which the organic fluid is essentially immiscible with water.

Claim 4

The process of claim 4 in which the fluid is a fluorocarbon.

Claim 5

The process of claim 5 in which the fluorocarbon is trichloromonofluoromethane.

Claim 6

The process of claim 1 in which the temperature of the hot gas is at least about 200* F. higher than the boiling point of the fluid.

Claim 7

The process of claim 1 in which the tobacco passed into said liquid state body is shredded tobacco.

Claim 8

A process of increasing the filling capacity of tobacco which comprises: a. maintaining a tobacco impregnating zone containing an organic fluid having a boiling point less than about 180* F. at a temperature between the atmospheric pressure boiling point of the fluid and 180* F. and under a superatmospheric pressure sufficient to provide a body of said fluid in the liquid state in a lower portion of said zone and a saturated vapor atmosphere of said fluid in an upper portion thereof, b. passing tobacco beneath the surface of said body within said zone to wet the tobacco with said liquid, c. thereafter passing the wetted tobacco to the upper portion of said zone whereby excess liquid drains away from the wetted tobacco, the residence time of said tobacco in said zone being sufficient to substantially completely impregnate same with said fluid, d. withdrawing the drained and impregnated tobacco from the upper portion of said zone, and e. thereafter immediately subjecting the so withdrawn tobacco to an elevated temperature and a reduced pressure sufficient to expand said tobacco.

Claim 9

The process of claim 9 wherein the tobacco treated is shredded tobacco.

Claim 10

The process of claim 9 wherein said last mentioned elevated temperature is above the boiling point of water at said reduced pressure.

Claim 11

The process of claim 9 wherein the tobacco passed into the impregnating zone has a moisture content of between about 10 and 30 parts by weight of water per 100 parts by weight of tobacco.

Claim 12

The process of claim 9 wherein the last-mentioned heating step is effected by passing the tobacco into a stream of hot gas and the expanded tobacco is thereafter separated from said stream.

Claim 13

The process of claim 13 is which the gas separated from the expanded tobacco includes a substantial percentage of vapors of the organic fluid and at least a portion of which provides the stream into which the tobacco is passed from the impregnating zone.

Claim 14

A process of treating tobacco which comprises a. passing a stream of an organic fluid having a boiling point less than about 180* F. into a tobacco impregnating zone, b. heating said zone to a temperature above the atmospheric pressure boiling point of said fluid but below about 180* F. under pressure sufficient to maintain a body of said fluid in the liquid state in a lower portion of said impregnating zone and a saturated vapor atmosphere of said fluid in an upper portion thereof, c. passing a stream of tobacco having a moisture content of between about 10 and 30 parts by weight of water per 100 parts by weight of tobacco (dry basis) into said liquid body in the lower portion of a tobacco impregnating zone, d. moving the organic liquid wetted tobacco to the upper portion of zone whereby excess liquid drains from the tobacco and returns to said lower portion, e. withdrawing the drained and impregnated tobacco from the upper portion of said impregnating zone, f. immediately contacting the so withdrawn tobacco with a stream of hot gas at a pressure less than that prevailing in said impregnating zone and at a temperature above the boiling point of water at said last-mentioned pressure, g. separating the resulting expanded tobacco from said hot gas stream, and h. recycling at least a portion of said hot gas stream as the stream for contacting the tobacco withdrawn from said contacting zone.

Claim 15

The process of claim 15 wherein the temperature at which the hot gas stream and tobacco are contacted is between about 250* and 400* F. and the time of contact is sufficient to expand the tobacco but insufficient significantly to impair the smoking qualities thereof.

Claim 16

The process of claim 15 wherein the temperature within said impregnating zone is between about 100* and 170* F. and the organic fluid is trichloromonofluoromethane.

Claim 17

The process of claim 15 in which the flow of said stream of organic fluid into said impregnating zone is controlled by the liquid level of said liquid body in the lower portion of said impregnating zone.