Pretreatment apparatus for removing pith from cornstalk, pulp manufacturing method using cornstalk, and paper manufacturing method using cornstalk pulp

Abstract

A pretreatment apparatus for removing pith from cornstalks and separating husks therefrom includes a casing that receives cornstalks in a free-fall manner through an upper side thereof and allows the corn stalks to be discharged through a lower side thereof, and a rotor inserted into the casing and rotating inside the casing to hit cornstalk chips. The rotor includes a shaft inserted into the casing to be rotated by external force, a cover member holding the shaft so as to allow rotation of the shaft therein and connected to the entirety or part of an open upper side of the casing, and a hitting unit formed on a circumference of the shaft and hitting the corn stalks input into the casing.

1 . A pretreatment apparatus for removing pith from cornstalks and separating husks therefrom, comprising:
 a casing which receives cornstalks in a free-fall manner through an upper side thereof and allows the corn stalks to be discharged through a lower side thereof; and   a rotor inserted into the casing and rotating inside the casing to hit cornstalk chips, the rotor comprising:
 a shaft inserted into the casing to be rotated by external force, 
 a cover member holding the shaft so as to allow rotation of the shaft therein and connected to the entirety or part of an open upper side of the casing, and 
 a hitting unit formed on a circumference of the shaft and hitting the corn stalks input into the casing. 
   
     
     
         2 . The pretreatment apparatus of  claim 1 , wherein the hitting unit comprises a plurality of plates disposed in an axial direction of the shaft, and a plurality of bars disposed along an edge of each plate. 
     
     
         3 . The pretreatment apparatus of  claim 2 , wherein the hitting unit comprises a hitting rib detachably attached to the bar and hitting the cornstalks falling through the lower side of the casing. 
     
     
         4 . The pretreatment apparatus of  claim 3 , wherein the bar or the hitting rib has a curved section. 
     
     
         5 . The pretreatment apparatus of  claim 2 , wherein the shaft is connected to a gear box to allow adjustment of rotational speed thereof. 
     
     
         6 . The pretreatment apparatus of  claim 1 , wherein the casing comprises a baffle formed on an inner surface thereof to enhance hitting force with respect to the cornstalks. 
     
     
         7 . The pretreatment apparatus of  claim 1 , wherein the casing is formed at an upper side or circumference thereof with an input gate through which the cornstalks are supplied into the casing, and the cornstalks are continuously supplied by a caterpillar feeder when poured into the input gate of the casing. 
     
     
         8 . The pretreatment apparatus of  claim 1 , wherein the casing comprises a vibrating screen unit which divides the cornstalks according to the size of the corn stalks while the cornstalks are hit and falling down. 
     
     
         9 . The pretreatment apparatus of  claim 8 , wherein the vibrating screen unit comprises a frame placed below the casing to discharge the cornstalks hit and falling down, a group of mesh screens slantly stacked inside the frame and disposed to have mesh sizes gradually increasing from a lower side to an upper side to sieve cornstalks corresponding to the respective mesh screens, a discharge hole formed on a circumference of the frame to discharge the cornstalks sieved by the respective mesh screens, and a vibrator vibrating the frame. 
     
     
         10 . The pretreatment apparatus of  claim 8 , wherein the cornstalks divided and sieved according to size of the cornstalks is returned to the casing by a feedback feeder. 
     
     
         11 . A pulp manufacturing method using a pretreatment apparatus for removing pith from cornstalks and separating husks therefrom, comprising:
 cutting cornstalks to a length of 10 to 60 mm;   hitting the cut cornstalks using a rotating hitting device; and   performing cornstalk pretreatment to sieve husk and pith of the cornstalks, and fragments of the husk.   
     
     
         12 . The method of  claim 11 , further comprising:
 cooking cornstalk chips obtained by the cornstalk pretreatment using sodium hydroxide and/or the mixture of sodium hydroxide and sodium carbonate.   
     
     
         13 . The method of  claim 12 , wherein the cooking is performed in a 12 to 16% active alkali at a liquor ratio of 3:1 to 6:1 and a temperature of 120 to 150° C. for 60 to 150 minutes. 
     
     
         14 . The method of  claim 12 , wherein the cooking comprises adding 0.05 to 0.2% anthraquinone to increase pulp yield and to minimize dissolution of hemicellulose. 
     
     
         15 . A method of manufacturing industrial paper through combination of 100% unbleached cornstalk pulp, unbleached softwood bleached kraft pulp or unbleached hardwood kraft pulp manufactured by the method of  claim 11 . 
     
     
         16 . A method of manufacturing toilet paper and tissue paper using the bleached cornstalk pulp manufactured by the method of  claim 11 . 
     
     
         17 . A method of manufacturing printing paper by performing mechanical treatment to bleached cornstalk pulp, and mixing the bleached cornstalk pulp with at least one of softwood bleached chemical pulp, hardwood bleached chemical pulp, and BCTMP.