Process for treating a slurry of cellulosic material
AssigneesThe Ontario Paper Company Limited, Canadian International Paper Company
InventorErnest Arthur Sexton
Life of this patent
Estimating the term…
Abstract
A slurry of cellulosic material is diluted to a flowable consistency and subjected to a pressure differential on a permeable surface to increase the slurry consistency to a value between the consistency of the diluted slurry and the consistency of th slurry prior to dilution thereby forming a mat of cellulosic material on the permeable surface. The liquid and solids which pass through the permeable surface as a result of the pressure differential are recycled for use as slurry diluent, and to the mat of cellulosic material is applied a treating liquid, such as a washing liquid.
Claims21
A process for treating a slurry of cellulosic material including application of a treating liquid to a mat of the cellulosic material which comprises:
- a. diluting the slurry to reduce its consistency to a flowable level;
- b. depositing the diluted slurry on a surface permeable to the liquid and solid phase thereof but which is substantially more permeable to the liquid phase;
- c. subjecting the deposited slurry to a pressure differential, whereby more of the liquid phase thereof than the solid phase passes through the permeable surface to increase the consistency of the slurry to a value between the consistency of the diluted slurry deposited on the surface and the consistency of the slurry prior to its dilution, thereby forming a mat of cellulosic material on said surface;
- d. recycling substantially all of the liquid and solids which pass through the surface for use as the slurry diluent in step (a);
- and then
- e. applying the treating liquid to the mat of cellulosic material on said surface.
Dependencies are inferred from the claim text.