Method of producing homogeneous sheets of nicotine-free vegetable fibers

Abstract

Method for producing homogeneous sheets of nicotine-free vegetable fibers includes:crushing up solid components of a raw material containing the nicotine-free vegetable fibers to bring them to a particle size of about 20-220 μm,mixing the crushed-up product thus obtained with water, at least one binding agent and at least one material to form an aerosol, until a mixture is obtained with a liquid content of about 30-50%,subjecting the mixture to a first lamination to obtain a continuous strip with a thickness of about 1-20 mm,subjecting the strip which has already been subjected to the first lamination to a series of further lamination steps, until a strip having a remarkably constant thickness of about 90-280 μm is obtained, anddrying the strip to a liquid content of about 8-15%.

1 . Method for producing homogeneous sheets of nicotine-free vegetable fibers comprising:
 crushing up solid components of a raw material containing the nicotine-free vegetable fibers to bring them to a particle size of about 20-220 μm,   mixing the crushed product thus obtained with water, at least one binding agent and at least one material to form an aerosol, until a mixture is obtained with a liquid content of about 30-50%,   subjecting said mixture to a first lamination to obtain a continuous strip with a thickness of about 1-20 mm,   subjecting said strip which has already been subjected to said first lamination to a series of further lamination steps, until a strip having a remarkably constant thickness of about 90-280 μm, is obtained, and   drying said strip to a liquid content of about 8-15%.   
     
     
         2 . The method according to  claim 1 , wherein the dried continuous strip is subjected to winding or transversal cutting or shredding into threads of predefined dimensions. 
     
     
         3 . The method according to  claim 1 , wherein the solid components of said raw material are crushed by grinding. 
     
     
         4 . The method according to  claim 1 , wherein the solid components of said raw material are crushed with a mill. 
     
     
         5 . The method according to  claim 1 , wherein the solid components of said raw material are crushed with a cryogenic pin mill ( 12 ). 
     
     
         6 . The method according to  claim 1 , wherein powdered cellulose is also mixed with the other substances that form the mixture. 
     
     
         7 . The method according to  claim 6 , wherein
 powdered cellulose consisting of an organic fiber obtained from natural cellulose is used.   
     
     
         8 . The method according to  claim 6 , wherein a slurry is formed with powdered cellulose having a particle size between 50 and 100 μm. 
     
     
         9 . The method according to  claim 1 , wherein said mixture is formed with powdered cellulose in a percentage comprised between 2% and 10% of the weight of the raw material. 
     
     
         10 . The method according to  claim 1 , wherein before forming said mixture with the crushed components of said raw material, said crushed components are mixed with powdered cellulose. 
     
     
         11 . The method according to  claim 10 , wherein the mixture formed by crushed product, possible powdered cellulose, water, at least one binding agent and at least one material for forming an aerosol is subjected to at least one of:
 a roughing step by passing through at least one pair of grooved cylinders ( 84 ) or   a refining step by passing through at least one pair of refining cylinders ( 124 , 124 ′) until it reaches a particle size not exceeding 20 μm.   
     
     
         12 . The method according to  claim 1 , wherein said mixture is subjected to a step of homogenization and forming before subjecting it to a first rolling step. 
     
     
         13 . The method according to  claim 12 , wherein said mixture is subjected to a homogenization and shaping phase for its transformation into a continuous strip, with a substantially constant width between 100 and 2000 mm and thickness between 1 and 10 mm, to then be subjected to said first lamination step. 
     
     
         14 . The method according to  claim 1 , wherein said mixture is subjected to a homogenization and shaping step for its transformation into a sequence of portions ( 82 ) to be then subjected to a first rolling step. 
     
     
         15 . The method according to  claim 1 , further comprising carrying out a first rolling of the mixture with a unit ( 90 ) comprising a lobe feeder ( 92 ) and at least one pair of rolling cylinders ( 98 ). 
     
     
         16 . The method according to  claim 1 , wherein said first lamination comprises a homogenization step which is carried out before obtaining said continuous strip having a thickness of about 1-20 mm. 
     
     
         17 . The method according to  claim 1 , wherein said mixture is subjected in sequence first to a forming step to transform the mixture into a sequence of portions ( 82 ) and subsequently to a step of homogenizing said portions ( 82 ) before obtaining from the portions said continuous strip having a thickness of about 1-20 mm. 
     
     
         18 . The method according to  claim 1 , wherein said mixture is homogenized mainly or exclusively by means of a lobe feeder ( 92 ) positioned at an inlet of at least one pair of rolling rolls ( 98 ). 
     
     
         19 . The method according to  claim 1 , wherein at the outlet of said first lamination a single-layer tape with a thickness of about 1-10 mm is obtained. 
     
     
         20 . The method according to  claim 1 , wherein, before subjecting said strip, already subjected to said first lamination, to said series of further lamination steps, it is subjected to stratification until a multilayer strip of thickness is obtained of about 2-20 mm. 
     
     
         21 . The method according to  claim 20 , wherein, in said series of further rolling steps, the mixture is allowed to rest between one rolling station and the next. 
     
     
         22 . The method according to  claim 1 , wherein the lamination is carried out with pairs of cylinders ( 108 ) that are at least partially heated. 
     
     
         23 . The method according to  claim 1 , wherein said laminated strip is dried by passing through a recirculating air dryer ( 114 ). 
     
     
         24 . The method according to  claim 1 , wherein vegetable fibers of at least one of the following vegetable substances are used: potato, hemp, tea, chamomile, mint, sage, rosemary or eucalyptus. 
     
     
         25 . The method according to  claim 1 , wherein said first lamination is carried out in a unit of first lamination ( 90 ), which comprises a homogenization module of the mixture, located immediately upstream with respect to a pre-rolling module, which is defined by at least one pair of lamination rolls ( 98 ), which are configured to form a continuous strip with a thickness of about 1-20 mm. 
     
     
         26 . The method according to  claim 25 , wherein said homogenization module comprises a lobe feeder ( 92 ). 
     
     
         27 . The method according to  claim 1 , wherein said at least one binding agent is selected from the group consisting of: hydroxypropylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, microcrystalline cellulose, methylcellulose, carboxymethylcellulose, corn starch, potato starch, guar gum, locust bean gum, pectin, alginates, ammonium alginate and sodium alginates.