Cellulosic fiber web treatment systems and associated processes

Abstract

Systems and processes are provided for the treatment of cellulosic pulp rolls. Generally, the systems and processes apply a series of compositions, such as debonding compositions, binder compositions and lubricant compositions, to cellulosic fiber webs provided on pulp rolls. The systems and processes provide a cost effective means by which to form cellulosic fiber pellets which may then be incorporated into a variety of end uses.

That which is claimed:  
     
         1 . A cellulosic fiber treatment system comprising: 
 (a) a source of cellulosic fiber web, said cellulosic fiber web defining first and second surfaces;    (b) at least one spray applicator to direct a debonding composition onto the first surface of the cellulosic fiber web;    (c) at least one rolling nip press to extract excess water from the saturated web;    (d) at least one powder applicator to direct a binder composition onto the first surface of the pressed web;    (e) at least one atomizer to direct a lubricant composition onto the first surface of the surface of the powder coated web; and    (f) a repulper to defibrilize the lubricated web.    
     
     
         2 . A cellulosic fiber web treatment system according to  claim 1 , wherein said spray applicator comprises at least one linear array of spray nozzles arranged across the width of the cellulosic fiber web.  
     
     
         3 . A cellulosic fiber web treatment system according to  claim 2 , wherein said spray nozzles span the cellulosic fiber web in the transverse direction.  
     
     
         4 . A cellulosic fiber web treatment system according to  claim 2 , wherein said spray nozzles are positioned at a center to center distance ranging from about 1 to 36 inches.  
     
     
         5 . A cellulosic fiber web treatment system according to  claim 1  including more than one spray applicators, said more than one spray applicators directing debonding composition onto both the first and second surfaces of the cellulosic fiber web.  
     
     
         6 . A cellulosic fiber web treatment system according to  claim 1 , wherein said rolling nip press comprises two co-rotating rolls.  
     
     
         7 . A cellulosic fiber web treatment system according to  claim 6 , wherein said co-rotating rolls define an outer surface formed from a material selected from stainless steel, ceramic, rubber or polytetrafluoroethylene.  
     
     
         8 . A cellulosic fiber web treatment system according to  claim 1 , wherein said powder applicator comprises an elongated funnel-shaped body terminating in a mesh screen.  
     
     
         9 . A cellulosic fiber web treatment system according to  claim 8 , wherein the mesh screen has a mesh size ranging from about 1 to 5 mm.  
     
     
         10 . A cellulosic fiber web treatment system according to  claim 1 , wherein said powder applicator spans the width of the cellulosic fiber web in the transverse direction.  
     
     
         11 . A cellulosic fiber web treatment system according to  claim 1  including more than one powder applicators, said more than one powder applicators directing binder composition onto both the first and second surfaces of the cellulosic fiber web.  
     
     
         12 . A cellulosic fiber web treatment system according to  claim 1 , wherein said atomizer comprises a linear array of atomizer heads arranged across the width of the cellulosic fiber web.  
     
     
         13 . A cellulosic fiber web treatment system according to  claim 1 , wherein said atomizer comprises a single row of atomizer heads spatially arranged to span the cellulosic fiber web in the transverse direction.  
     
     
         14 . A cellulosic fiber web treatment system according to  claim 1 , wherein said atomizer heads are positioned at a center to center distance ranging from about 1 to 24 inches.  
     
     
         15 . A cellulosic fiber web treatment system according to  claim 1  including more than one atomizers, said more than one atomizers directing lubricant composition onto both the first and second surfaces of the cellulosic fiber web.  
     
     
         16 . A cellulosic fiber web treatment system according to  claim 1 , wherein said repulper comprises rotating breaker bars.  
     
     
         17 . A cellulosic fiber web treatment system according to  claim 1 , further comprising a fiber pelletizer.  
     
     
         18 . A cellulosic fiber web treatment method comprising: 
 (a) supplying a cellulosic fiber web to a treatment system;    (b) applying an effective amount of a debonding composition onto at least a first surface of the cellulosic fiber web;    (c) extracting excess water from the cellulosic fiber web;    (d) applying an effective amount of a binder composition onto at least the first surface of the cellulosic fiber web;    (e) applying an effective amount of a lubricant composition onto at least the first surface of the cellulosic fiber web; and    (f) defibrilizing the lubricated web.    
     
     
         19 . A cellulosic fiber web treatment method according to  claim 18 , wherein the debonding composition is applied to at least the first surface of the cellulosic fiber web in an amount ranging from about 0 to 3000 pounds per hour.  
     
     
         20 . A cellulosic fiber web treatment method according to  claim 18 , wherein the extracting step is operated at a nip pressure ranging from about 50 to 150 psi.  
     
     
         21 . A cellulosic fiber web treatment method according to  claim 18 , wherein the binder composition is applied to the surface of the pressed web in an amount ranging from about 0 to 30 pounds per hour.  
     
     
         22 . A cellulosic fiber web treatment method according to  claim 18 , wherein the lubricant composition is applied to the surface of the powder coated web in an amount ranging from about 0 to 50 pounds per hour.  
     
     
         23 . A treated cellulosic fiber web comprising: 
 (a) a cellulosic fiber web;    (b) an effective amount of a debonding composition;    (d) an effective amount of a binder composition; and    (e) an effective amount of a lubricant composition.    
     
     
         24 . A treated cellulosic fiber web according to  claim 23 , wherein said cellulosic fiber web is formed from cellulosic pulp fibers having an alpha-cellulose purity of greater than about 80% by weight.  
     
     
         25 . A treated cellulosic fiber web according to  claim 24 , wherein said cellulosic pulp fibers have an alpha-cellulose purity greater than about 98% by weight.  
     
     
         26 . A treated cellulosic fiber web according to  claim 23 , wherein said debonding composition includes at least one surfactant as a debonding agent.  
     
     
         27 . A treated cellulosic fiber web according to  claim 26 , wherein said debonding agent is present within the treated cellulosic fiber web in amounts ranging from about 0 to 5 weight percent, based on the weight of the cellulosic pulp fibers.  
     
     
         28 . A treated cellulosic fiber web according to  claim 23 , wherein said binder composition includes at least one water soluble binder selected from polyacrylamide, polyacrylic acid, poly(n-vinyl pyrroliddinone), sodium carboxymethyl cellulose, polyvinyl alcohol, polyethylene glycol, sodium hydroxy ethyl cellulose, sodium carboxy methyl hydroxy ethyl cellulose, sodium hydroxy propyl cellulose and mixtures thereof.  
     
     
         29 . A treated cellulosic fiber web according to  claim 28 , wherein said water soluble binder is polyacrylamide.  
     
     
         30 . A treated cellulosic fiber web according to  claim 28 , wherein said at least one water soluble binder is present in an amount of about 0.1 to 1.0 weight percent, based on the weight of the cellulosic pulp fibers.  
     
     
         31 . A treated cellulosic fiber web according to  claim 23 , wherein said lubricant composition includes at least one lubricant selected from silicone oil, fatty amides, metal stearates, and mixtures thereof.  
     
     
         32 . A treated cellulosic fiber web according to  claim 31 , wherein said lubricant is a mixture comprising silicone oil and ethylene bisstearamid.  
     
     
         33 . A treated cellulosic fiber web according to  claim 32 , wherein said silicone oil is present at about a 2:1 weight ratio in comparison to said ethylene bisstearamid.  
     
     
         34 . A treated cellulosic fiber web according to  claim 31 , wherein said at least one lubricant is present in an amount ranging from about 1.0 to 10.0 weight percent, based on the weight of the cellulosic pulp fibers.  
     
     
         35 . A treated cellulosic fiber web according to  claim 23 , wherein said binder composition further comprises at least one coupling agent selected from titanates, zirconates, silanes and mixtures thereof.  
     
     
         36 . A treated cellulosic fiber web according to  claim 35 , wherein said coupling agent is present in said binder composition in an amount of up to about 1.0 weight percent, based on the weight of the binder composition.  
     
     
         37 . A treated cellulosic fiber web according to  claim 23  comprising: 
 cellulosic pulp fibers having an alpha-cellulose purity of greater than 80% by weight;  
 a debonding agent comprising surfactant;  
 a water soluble binder comprising polyacrylamide; and  
 a lubricant mixture comprising silicone oil and ethylene bisstearamid.  
 
     
     
         38 . A treated cellulosic fiber web according to  claim 37 , wherein said debonding agent is present in an amount of up to about 5.0 weight percent, based on the weight of the cellulosic pulp fiber; 
 said water soluble binder is present in an amount ranging from about 0.1 to 1.0 weight percent, based on the weight of the cellulosic pulp fiber; and    said lubricant mixture is present in an amount ranging from about 1.0 to 10.0 weight percent, based on the weight of the cellulosic pulp fiber.