Process and apparatus for reordering expanded tobacco

Abstract

A process reorders tobacco that has been expanded by impregnating the tobacco under pressure with liquid carbon dioxide, forming a solid mass of the tobacco and solid carbon dioxide, and heating the solid mass in an expansion zone to sublimate the carbon dioxide and thereby expand the tobacco. The expanded tobacco is discharged from the expansion zone and before the temperature of the expanded tobacco is below about 80° F., the tobacco is contacted with humidifying air having a temperature of about 80° F. to about 91 ° F. and a relative humidity of about 58% to about 88%.

What is claimed is:  
     
         1 . A process for reordering carbon dioxide expanded tobacco having a moisture content of less than about 8% that has been heated to about 180° F. to about 250° F. during expansion in an expansion zone comprising: 
 discharging the expanded tobacco from the expansion zone into a reordering zone; and  
 blowing humidifying air through the tobacco in the reordering zone before the temperature of the tobacco decreases to a temperature below about 80° F. to increase the moisture content of the tobacco to at least about 14%, the humidifying air having a temperature of about 80° F. to about 91° F. and a relative humidity of from about 58% to about 88%.  
 
     
     
         2 . The process of  claim 1 , wherein the reordering zone is a vibrating conveyor with an air permeable floor, the tobacco being deposited on the floor and the air being blown upwardly through the floor and the tobacco.  
     
     
         3 . The process of  claim 2  wherein the tobacco is deposited on the floor at a rate to provide a thickness of tobacco on the floor of about 0.25 to about 4 inches.  
     
     
         4 . The process of  claim 1 , wherein the moisture content is increased from less than 8% to at least 12% in less than 15 minutes.  
     
     
         5 . The process of  claim 1 , wherein the moisture content is increased from less than 8% to at least 12% in from about 6 to about 12 minutes.  
     
     
         6 . The process of  claim 1 , wherein the tobacco is cut tobacco filler.  
     
     
         7 . The process of  claim 2  wherein the air is blown at a velocity of from about 15 CFM to about 30 CFM per square foot of the floor.  
     
     
         8 . The process of  claim 1 , wherein tobacco has a temperature of from about 180° F. to about 250° F. when contacted by the humidifying air.  
     
     
         9 . The process of  claim 1  wherein the relative humidity of the humidifying air is from about 68% to about 78%.  
     
     
         10 . The process of  claim 1  wherein the relative humidity of the humidifying air is about 78%.  
     
     
         11 . A process for expanding and reordering tobacco comprising: 
 impregnating the tobacco under pressure with a liquid impregnant;    converting the liquid impregnant to solid to form a solid mass of the tobacco and solid;    heating the solid mass in an expansion zone to a temperature of about 180° F. to about 250° F. to convert the impregnant to a gas, and thereby expand the tobacco;    discharging the expanded tobacco from the expansion zone; and    initially contacting the expanded tobacco with humidifying air having a temperature of about 80° F. to about 91° F. and a relative humidity of about 58 to about 88% before the temperature of expanded tobacco falls below about 80° F.    
     
     
         12 . The process of  claim 11 , wherein the expanded tobacco is contacted with humidifying air for from about 2 to about 15 minutes.  
     
     
         13 . The process of  claim 11 , wherein the expanded tobacco is contacted with humidifying air for from about 8 to about 12 minutes.  
     
     
         14 . The process of  claim 11 , wherein the moisture content of the expanded tobacco is raised to about 12 to 14%.  
     
     
         15 . The process of  claim 11 , including forming a bed of the tobacco when the tobacco is discharged from the expansion zone, and blowing humidifying air through the tobacco bed.  
     
     
         16 . The process of  claim 11 , wherein the tobacco is deposited on the floor at a rate to provide a thickness of tobacco on the floor of about 0.25 to about 4 inches.  
     
     
         17 . The process of  claim 11 , wherein the tobacco is cut tobacco filler.  
     
     
         18 . The process of  claim 11 , wherein tobacco has a temperature of from about 180° F. to about 250° F. when contacted by the humidifying air.  
     
     
         19  The process of  claim 11  wherein the relative humidity of the humidifying air is from about 68% to about 78%.  
     
     
         20 . The process of  claim 11  wherein the relative humidity of the humidifying air is about 78%.  
     
     
         21 . A process for expanding and reordering tobacco comprising: 
 providing a sublimator having a discharge opening and an air permeable conveyor having a feed end adjacent the sublimator discharge opening and a discharge end;    placing solid impregnated tobacco into the sublimator;    heating the tobacco in the sublimator to a temperature of at least about 180° F. to convert the impregnant to a gas to thereby expand the tobacco;    discharging the expanded tobacco having a temperature of at least 180° F. from the sublimator discharge opening onto the feed end of the conveyor; and    blowing humidifying air through the tobacco while the tobacco is conveyed from the feed end of the conveyor to the discharge end of the conveyor to increase the moisture content of the tobacco to at least about 12%, the humidifying air having a temperature of from about 80° F. to about 90° F. and a relative humidity of about 58% to about 88%.    
     
     
         22 . The process of  claim 21 , wherein the conveyor is a vibrating conveyor having an air permeable floor, the air being blown upwardly through the floor and the tobacco.  
     
     
         23 . The process of  claim 21  wherein the tobacco is deposited on the floor at a rate to provide a thickness of tobacco on the floor of about 0.25 about 4 inches.  
     
     
         24 . The process of  claim 21 , wherein the tobacco is conveyed from the conveyor feed end to the discharge end is from about 6 to about 12 minutes.  
     
     
         25 . The process of  claim 21 , wherein the air is blown through the tobacco at the rate of from about 15 CFM/sq. ft. of conveyor to about 30 CFM/sq. ft. of conveyor.  
     
     
         26 . The process of  claim 21 , wherein the tobacco is discharged from the sublimator at a temperature of from about 180° F. to about 250° F.  
     
     
         27 . The process of  claim 21 , wherein the tobacco when discharged from the sublimator has a moisture content of less than about 8%.  
     
     
         28 . The process of  claim 21 , wherein the tobacco is cut tobacco filler.  
     
     
         29 . The process of  claim 21 , wherein the relative humidity of the humidifying air is from about 68% to about 78%.  
     
     
         30 . The process of  claim 21 , wherein the relative humidity of the humidifying air is about 78%.  
     
     
         31 . An apparatus for expanding and reordering tobacco comprising: 
 a tobacco expander having an expansion zone to expose tobacco impregnated with an impregnant to heat to sublimate the impregnant from the tobacco to cause tobacco expansion, resulting in expanded, elevated temperature tobacco, the expansion zone having a discharge outlet to discharge expanded, elevated temperature tobacco, and    a reordering zone downstream of the expansion zone and close enough to the discharge outlet of the expansion zone so that the expanded, elevated temperature tobacco remains at an elevated temperature when it reaches the expansion zone, the reordering zone including a blower to blow humidified air through the expanded, elevated temperature tobacco in the reordering zone.    
     
     
         32 . An apparatus as claimed in  claim 31  further comprising a conditioner for the humidified air to adjust the relative humidity and temperature of the humidified air to desired levels.  
     
     
         33 . An apparatus as claimed in  claim 32  wherein the desired level of temperature is between about 80° F. and about 91° F.  
     
     
         34 . An apparatus as claimed in  claim 32  wherein the desired level of relative humidity is between 58% and about 88%.  
     
     
         35 . An apparatus as claimed in  claim 32  wherein the desired level of relative humidity is between about 68% and about 78%.  
     
     
         36 . An apparatus as claimed in  claim 31  wherein the desired level of relative humidity is about 78%  
     
     
         37 . A process for reordering carbon dioxide expanded tobacco having a moisture content of less than about 8% that has been heated to about 180° F. to about 250° F. during expansion in an expansion zone comprising: 
 discharging the expanded tobacco cut filler from the expansion zone onto a vibrating conveyor with an air permeable floor at a rate to provide a thickness of tobacco on the floor of about 0.25 to about 4 inches, and  
 blowing humidifying air having a relative humidity of about 78% upwardly through the floor of the conveyor and through the tobacco at a velocity of from about 15 CFM to about 30 CFM per square foot of the floor to increase the moisture content of the tobacco, the humidifying air having a temperature of about 80° F. to about 91° F.,  
 wherein the tobacco has a temperature of from about 180° F. to about 250° F. when first contacted by the humidifying air and the moisture content is increased from less than 8% to at least 12% in from about 6 to about 12 minutes.