Abstract: Disclosed is a method of producing an expanded tobacco material. According to the method, a tobacco material (TM) is fed into a pressure vessel (11), followed by pressurizing the interior of the pressure vessel (11) with a carbon dioxide gas to a predetermined impregnation pressure. Then, a liquid carbon dioxide (21) is supplied from above the tobacco material (TM) into the pressure vessel through a sintered metal plate (13), etc., while maintaining the impregnation pressure, thereby saturating the interior of the pressure vessel (11) with a carbon dioxide gas generated by vaporization of the supplied liquid carbon dioxide, and cooling the tobacco material by the latent heat of vaporization of the liquid carbon dioxide, so as to impregnate the tobacco material with carbon dioxide. The tobacco material impregnated with carbon dioxide is brought into contact with a hot gaseous stream within a gaseous stream dryer so as to expand the tobacco material.

Abstract: Tobacco is treated to cause its expansion by a process which comprises the steps of subjecting it, in a treatment chamber, to a reduced pressure of not greater than 7 kPa, impregnating the cell structure of the tobacco with isopentane vapour at a temperature in the range of from 70.degree. C. to 100.degree. C. and maintaining the tobacco in contact with the vapour at a pressure of at least 400 kPa, removing excess isopentane vapour from the treatment chamber, contacting the impregnated tobacco with steam to expand the tobacco cell structure, reducing the pressure in the treatment chamber at a rate of at lest 10 kPa/minute, preferably 30 kPa/minute, and then venting the treatment chamber back to atmospheric pressure. The final filling value of the tobacco treated according to this process is directly proportional to the rate at which the pressure in the treatment chamber is reduced following the steam treatment of the tobacco.

Abstract: In a process for expanding tobacco, an equilibrium pressure within a process vessel (1) containing a mixture of gaseous carbon dioxide and liquid carbon dioxide is selected before charging a sample volume of tobacco from a batch of tobacco into a sealable impregnator vessel (2). Liquid carbon dioxide is then transferred at the selected equilibrium pressure from the process vessel (1) into the impregnator vessel (2) where it is maintained sufficiently long to permit liquefied carbon dioxide to penetrate the cells of the tobacco. Liquid carbon dioxide is subsequently transferred from the impregnator vessel (2) into a drain vessel (3) and the pressure within the impregnator vessel (2) is reduced sufficiently to cause the solidification of liquid carbon dioxide contained within the cells of the tobacco. Finally, the tobacco is heated sufficiently to vaporise the carbon dioxide in the tobacco cells thereby expanding the tobacco.

Abstract: An expanding apparatus supplies an expanding agent to an impregnating vessel, and continuously supplies and discharges a material, e.g., a tobacco material to and from the impregnating vessel through a valve while pressure-increasing or pressure-decreasing the material, thereby continuously expanding the material. The expanding agent supplied to the impregnating vessel, the valve, and the like is recovered and, air, an impurity gas, or the like mixed in it is removed. Thereafter the expanding agent is pressure-increased to a high pressure and supplied to the impregnating vessel and the valve again.

Abstract: An expanding apparatus continuously expands a material, e.g., a tobacco material and supplies gaseous carbon dioxide as an expanding agent to an impregnating vessel by an expanding agent supply to maintain a predetermined impregnating pressure. The material is continuously supplied to the impregnating vessel by a material supply while increasing the pressure of the material. The material is continuously discharged from the impregnating vessel by a material discharge while decreasing the pressure of the material. The expanding agent supply has a heat exchanger to perform heat exchange between carbon dioxide to be supplied to the impregnating vessel and a coolant, thereby cooling carbon dioxide. The state of carbon dioxide to be supplied to the impregnating vessel is controlled in accordance with the temperature or the like of the tobacco material discharged from the impregnating vessel, so that carbon dioxide is effectively impregnated and no dry ice is formed in the material discharge or the like.

Abstract: A process for expanding tobacco is provided which employs carbon dioxide gas. Tobacco temperature and OV content are adjusted prior to contacting the tobacco with carbon dioxide gas. A thermodynamic path is followed during impregnation which allows a controlled amount of the carbon dioxide gas to condense on the tobacco. This liquid carbon dioxide evaporates during depressurization helping to cool the tobacco bed uniformly. After impregnation, the tobacco may be expanded immediately or kept at or below its post-vent temperature in a dry atmosphere for subsequent expansion.

Abstract: A process for the expansion of tobacco, wherein in step (a) the tobacco is cooled by being mixed with cold carbon dioxide; (b) the cooled tobacco is impregnated with liquid carbon dioxide through treatment with gaseous carbon dioxide under a predetermined pressure; (c) the liquid carbon dioxide condensed in the tobacco is converted to solid carbon dioxide through pressure reduction; and (d) the tobacco containing solid carbon dioxide is subjected to a hot gas treatment to achieve the expansion. In step (a) the tobacco is cooled to a temperature of -30.degree. C. to -100.degree. C. through expansion of liquid carbon dioxide and the simultaneous mixing of the tobacco therewith.

Abstract: A process and apparatus for impregnating a cellular material with liquefied gas at a predetermined pressure for subsequent expansion of the impregnated cellular material including the steps of charging the cellular material into an impregnation vessel, purging the impregnation vessel with inert gas, pressurizing the impregnation vessel with inert gas to the predetermined pressure, transferring liquefied inert gas into the impregnation vessel from a process vessel in which the liquefied gas is stored at the predetermined pressure, soaking the cellular material in the liquefied inert gas for a predetermined time period, transferring unabsorbed liquefied gas from the impregnation vessel to the storage vessel, depressurizing the impregnation vessel by venting the inert gas therefrom and removing the impregnated cellular material from the impregnation vessel, the inert gas used to purge and pressurize the impregnation vessel being taken from a source completely independent of the liquefied inert gas contained in t

Abstract: A method is described for extracting tobacco alkaloids from tobacco in which the tobacco alkaloids are extracted from the tobacco with carbon dioxide under supercritical conditions and the tobacco alkaloids separated from the carbon dioxide, wherein in the carbon dioxide for the extraction of the tobacco alkaloids from the tobacco is mixed with a solid 2 to 3-basic organic acid having a total of 2 to 6 carbon atoms, a monoalkali or monoammonium salts thereof in order to appreciably shorten the extraction times.

Abstract: The invention is directed to a process for increasing the filling capacity of tobacco wherein tobacco is contacted with a mixture of an inert, normally gaseous expansion agent and about 15-35 weight percent of carbon dioxide at a pressure above the critical pressure of the mixture and a temperature above the critical temperature of the mixture, followed by rapid release of pressure to provide expanded tobacco without a subsequent heating step. Advantageously, the expansion agent is propane.

Abstract: A process for expanding tobacco includes the steps of adjusting the moisture content of cut tobacco, pressurizing the cut tobacco with or without treatment, releasing the pressurized cut tobacco rapidly into a dryer and reordering the tobacco. The apparatus includes a housing having at least one chamber and preferably a chamber divided into a plurality of isolated sectors. Tobacco is received in the chamber or in each sector and released quickly from the housing following at least the step of pressurization of tobacco by steam. The apparatus may be used for batch and continuous treatment of tobacco. According to the continuous treatment, the sectors are formed by a rotating member, and each sector of the member is filled with tobacco as the member rotates relative to an inlet. The inlet and an outlet through which treated tobacco falls are in vertical alignment.

Abstract: An improved tobacco treating expansion process involving controlling the moisture content of tobacco and the pre-separator residence time thereof in a treatment of the moisture controlled tobacco under preselected pressures and temperatures so that the tobacco at exit from the drying step of the process has a moisture content in the range of approximately 9% to approximately 15% oven volatiles by weight and fill values at least equivalent to fill values of tobaccos dried to a lower moisture content not exceeding 6% oven volatiles.

Abstract: An improved tobacco treating process comprising cooling tobacco in a liquid nitrogen bath, impregnating the mixture with carbon dioxide gas under preselected pressure conditions, releasing the pressure and subjecting the so treated tobacco to drying gases with temperatures at least above about 250.degree. F. with wet bulb temperatures in the range of at least about 150.degree. F. with a maximum of 212.degree. F.

Abstract: A method and apparatus for treating tobacco leaves by impregnating them with liquid carbon dioxide under high pressure. Tobacco leaf containers, in the form of open buckets, are mounted on a turntable which rotates intermittently step by step. In the preferred apparatus, the buckets are mounted in pairs, and when one pair of buckets is at a filling station, the buckets are filled with tobacco. The turntable then rotates to bring this filled pair of buckets to an impregnating station, while another pair of buckets is brought around to the filling station. At the impregnating station, lids are tightly applied and sealed to the buckets, and the impregnating liquid carbon dioxide is introduced, held for a predetermined time, and then released, after which the lids are removed.

Abstract: Tobacco impregnated with solid carbon dioxide is heated in a chamber to expand the same by sublimation of solid CO.sub.2 and expulsion of CO.sub.2 gas from the tobacco. The expanded tobacco is separated from the internal atmosphere of the expansion device and the tobacco is discharged through an outlet through which gas flows are substantially precluded. The evolved CO.sub.2 gas and other volatile components are removed from the chamber and a portion of the removed gas is heated and returned to the chamber as the expansion medium. The necessity for external steam is avoided as an atmosphere of high thermal diffusivity is maintained in the expansion chamber by precluding the entry of ambient air.

Abstract: Impregnated tobacco is expanded in an expansion operation involving the entrainment of the impregnated tobacco in a heated gas stream under high temperature-short entrainment time conditions resulting in a product of improved quality and enhanced expansion.

Abstract: A process for expanding tobacco is provided which employs liquid carbon dioxide as the expansion agent. Tobacco is contacted with liquid carbon dioxide to thoroughly impregnate the tobacco with the liquid carbon dioxide. The carbon dioxide impregnated tobacco is maintained at a temperature no lower than -2.degree. C. and under conditions of temperature and elevated pressure such that all or substantially all of the carbon dioxide which is in contact with the tobacco is in liquid form. After the impregnation has been completed, any excess liquid carbon dioxide which may be present with the tobacco may be removed from the tobacco. The elevated pressure is then reduced in order to convert the liquid carbon dioxide to solid carbon dioxide within the tobacco structure.

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: In a pressure vessel of the type used for processing a product with a liquid cryogen such as the impregnation of tobacco with liquid carbon dioxide for expansion thereof, a withdrawal door, pivotally hinged to open to permit gravitational discharge of the processed product, includes a grating to support the product in the vessel when the door is closed. A wire screen mesh is disposed on the grating to permit gaseous and liquid cryogen to pass therethrough while substantially preventing product from passing therethrough. A holding apparatus includes means for securely holding the screen fixed relative to the grating at the periphery and interior surface portions of the screen, the apparatus preferably including a gridded structure for minimizing stretching and tearing of the screen during discharge of the processed product from the vessel.

Abstract: The invention disclosed is a method and apparatus for expanding particles of cured tobacco by means of liquid and gaseous carbon dioxide which is sprayed into a mass of the tobacco in a closed pressure vessel. The thus treated tobacco is removed from the vessel and heated such that rapid release of the carbon dioxide effects expansion of the tobacco.

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: A process for expanding tobacco is provided which employs liquid carbon dioxide as the expansion agent. Tobacco is contacted with liquid carbon dioxide to thoroughly impregnate the tobacco with the liquid carbon dioxide. The carbon dioxide impregnated tobacco is maintained at a temperature no lower than -2.degree. C. and under conditions of temperature and elevated pressure such that all or substantially all of the carbon dioxide which is in contact with the tobacco is in liquid form. After the impregnation has been completed, any excess liquid carbon dioxide which may be present with the tobacco may be removed from the tobacco. The elevated pressure is then reduced in order to convert the liquid carbon dioxide to solid carbon dioxide within the tobacco structure.

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.