Device and method for dilution of cellulose pulp

Abstract

A device and a method for dilution of cellulose pulp of a consistency of between 20% and 45%. The cellulose pulp is arranged to fall down in a pulp chute during an addition of dilution liquid. The dilution is performed to a consistency in the range of 6-18%, above a level of established diluted pulp in a bottom of a pulp chute. A central distribution device with nozzles for addition of dilution liquid to the falling pulp above the level of established diluted pulp in the bottom of the pulp chute is arranged in the center of the pulp chute. The nozzles of the distribution device are fed with dilution liquid via a pipe that is arranged at least partly through the pulp chute.

1 . A device for dilution of cellulose pulp of a consistency of between 20% and 45%, comprising:
 a pulp chute through which cellulose pulp is arranged to fall down,   means for adding the dilution liquid on the falling pulp above a level of established diluted pulp at a bottom of the pulp chute to dilute the consistency to a range of 6-18%,   a central distribution device with a nozzle arranged in a center of the pulp chute adapted to add dilution liquid to the falling pulp in the center of the pulp chute and above the level of established diluted pulp at the bottom of the pulp chute, and   means for feeding the nozzle with dilution liquid via a pipe that is arranged at least partly through the pulp chute.   
     
     
         2 . The device according to  claim 1 , wherein the central distribution device has several nozzles that are evenly distributed over a width of the pulp chute. 
     
     
         3 . Device The device according to  claim 1  wherein a peripheral distribution device with peripheral nozzles is arranged for adding dilution liquid from an inner wall of the pulp chute. 
     
     
         4 . The device according to  claim 3 , wherein the central distribution device is arranged below the peripheral nozzles of the peripheral distribution device. 
     
     
         5 . The device according to  claim 4  wherein the device further comprises means for separating the feeding to the nozzles of the central distribution device from the feeding to the peripheral nozzles of the peripheral distribution device, and means for feeding dilution liquid from different sources to the peripheral nozzles of the peripheral device and the nozzle of the central distribution device. 
     
     
         6 . The device according to  claim 5  wherein a deaeration canal is arranged in connection to the pulp chute above the nozzle of the central distribution device and the peripheral nozzles of the peripheral device. 
     
     
         7 . A method for dilution of cellulose pulp having a consistency of between 20% and 45%, comprising:
 adding a dilution liquid to the cellulose pulp in a pulp chute, which dilution is performed to a consistency in a range of 6-18% as the cellulose pulp is in free fall above an established level of diluted cellulose pulp at a bottom of the pulp chute, and   adding dilution liquid in a center of the pulp chute.   
     
     
         8 . The method of  claim 7  wherein the dilution liquid is added from several nozzles that are substantially evenly distributed over a width of the pulp chute. 
     
     
         9 . The method of  claim 7  wherein dilution liquid also is added from an inner wall of the pulp chute. 
     
     
         10 . The method of  claim 9  wherein different dilution liquids are added in the center and a periphery of the pulp chute, wherein the dilution liquid added in the center of the pulp chute is more concentrated than the dilution liquid added in the periphery of the pulp chute. 
     
     
         11 . The method of  claim 7  wherein at least 25% of the dilution liquid is added in the center of the pulp chute.