Fiber loading improvements in papermaking

Abstract

A method of making paper includes mixing calcium hydroxide into a water and pulp fiber slurry. The method also includes reacting the calcium hydroxide and pulp fiber slurry under a carbon dioxide pressure. Further, the method includes causing calcium carbonate precipitate to form in response to the reacting.

1 - 20 . (canceled) 
     
     
         21 . A method of making paper, comprising:
 providing a cellulosic fibrous material comprising a plurality of elongated fibers having a fiber wall surrounding a hollow interior, the fibrous material having moisture at a level sufficient to provide the cellulosic fibrous material in the form of dewatered crumb pulp;   heating the dewatered crumb pulp in a first heating process by adding heat energy to the dewatered crumb pulp mixture in a steam condensation process;   adding calcium hydroxide particles to the dewatered crumb pulp to form a pulp mixture having between 5% and 60% solids by weight, in a manner such that at least some of the calcium hydroxide particles added have a mean nano-scale particle size in order to increase the rate of solubility for calcium ion release;   contacting the pulp mixture with carbon dioxide as carbonic acid in order to precipitate calcium carbonate partly within the cell walls of the fibrous material and displacing bound water to form a modified pulp mixture;   forming a web from the modified pulp mixture;   heating the web by adding energy to the web; and   wet pressing the web.   
     
     
         22 . The method of  claim 21 , further comprising:
 drying the web.   
     
     
         23 . The method of  claim 21 , wherein the mean particle size is in the range of 1 nanometer (nm) to 100 nanometers (nm). 
     
     
         24 . The method of  claim 21 , further comprising:
 removing water from the wet pressing.   
     
     
         25 . The method of  claim 21 , further comprising:
 removing calcium carbonate from the wet pressing.   
     
     
         26 . The method of  claim 21 , wherein contacting the pulp mixture includes pressurizing the pulp mixture. 
     
     
         27 . The method of  claim 21 , wherein contacting the pulp mixture includes pressurizing the pulp mixture with carbon dioxide gas in a range of 5 to 60 psig. 
     
     
         28 . The method of  claim 21 , wherein heating the web includes heating the web in a steam box. 
     
     
         29 . A method of making paper, comprising:
 providing a cellulosic fibrous material comprising a plurality of elongated fibers having a fiber wall surrounding a hollow interior, the fibrous material having moisture at a level sufficient to provide the cellulosic fibrous material in the form of dewatered crumb pulp;   heating the dewatered crumb pulp in a first heating process by adding heat energy to the dewatered crumb pulp mixture in a steam condensation process;   adding precipitated calcium carbonate particles to the dewatered crumb pulp to form a pulp mixture having between 5% and 60% solids by weight, in a manner such that at least some of the precipitated calcium carbonate particles added have a mean nano-scale particle size in order to increase the rate of solubility for calcium ion release;   subjecting the pulp mixture to high shear mixing, after heating the pulp mixture, so as to cause the cellulosic fibrous material to have a substantial amount of calcium carbonate loaded within the hollow interior and within the fiber walls of the plurality of cellulosic fibers;   forming a web from the pulp mixture which has been subjected to the heating and the high shear,   heating the web by adding energy to the web; and   wet pressing the web.   
     
     
         30 . The method of  claim 29 , further comprising:
 drying the web.   
     
     
         31 . The method of  claim 29 , wherein the mean particle size is in the range of 1 nanometer (nm) to 100 nanometers (nm). 
     
     
         32 . The method of  claim 29 , further comprising:
 removing water from the wet pressing.   
     
     
         33 . The method of  claim 29 , further comprising:
 removing calcium carbonate from the wet pressing.   
     
     
         34 . The method of  claim 29 , wherein subjecting the pulp mixture to high shear mixing includes pressurizing the pulp mixture. 
     
     
         35 . The method of  claim 29 , wherein subjecting the pulp mixture to high shear mixing includes pressurizing the pulp mixture with carbon dioxide gas in a range of 5 to 60 psig. 
     
     
         36 . The method of  claim 29 , wherein heating the web includes heating the web in a steam box. 
     
     
         37 . The method of  claim 29 , further comprising:
 adding carbon dioxide gas to the pulp mixture after adding the precipitated calcium carbonate particles to the pulp mixture.   
     
     
         38 . A system for making paper, comprising:
 a means for providing a cellulosic fibrous material comprising a plurality of elongated fibers having a fiber wall surrounding a hollow interior, the fibrous material having moisture at a level sufficient to provide the cellulosic fibrous material in the form of dewatered crumb pulp;   a means for heating the dewatered crumb pulp in a first heating process by adding heat energy to the dewatered crumb pulp mixture in a steam condensation process;   a means for adding calcium hydroxide particles to the dewatered crumb pulp to form a pulp mixture having between 5% and 60% solids by weight, in a manner such that at least some of the calcium hydroxide particles added have a mean nano-scale particle size in order to increase the rate of solubility for calcium ion release;   a means for contacting the pulp mixture with carbon dioxide as carbonic acid in order to precipitate calcium carbonate partly within the cell walls of the fibrous material and displacing bound water to form a modified pulp mixture;   a means for forming a web from the modified pulp mixture;   a means for heating the web by adding energy to the web; and   a means for wet pressing the web.   
     
     
         39 . The system of  claim 38 , further comprising:
 a means for drying the web.   
     
     
         40 . The system of  claim 38 , further comprising:
 a means for removing calcium carbonate from the wet pressing.