Methods for producing recycled pulp from waste paper

Abstract

The invention provides methods and apparatus for using waste paper to produce recycled pulp that can be used by the paper industry. The recycled pulp produced by the methods and apparatus of the invention can optionally be mixed with virgin pulp to produce paper or paper-products. The waste paper can be any grade, including low quality waste paper, such as mixed waste paper or old newsprint.

1 . A method for making recycled pulp comprising: 
 (a) providing waste material that comprises waste paper and, optionally, prohibitives;    (b) adding the waste material to a liquid-based fiber separator apparatus; and    (c) producing recycled pulp having a solids content from about 1 wt % to about 85 wt %.    
     
     
         2 . The method of  claim 1 , wherein the recycled pulp has a solids content from about 1 wt % to about 25 wt %.  
     
     
         3 . The method of  claim 1 , wherein the waste paper comprises a pulp substitute, a de-inking grade, a brown kraft grade, mixed waste paper, or a mixture of two or more thereof.  
     
     
         4 . The method of  claim 1 , wherein the waste paper comprises one or more grades selected from (1); (2); (4); (5); (6); (7); (8); (9); (10); (11); (12); (13); (15); (16); (17); (18); (19); (24); (21); (22); (23); (24); (25); (26); (27); (28); (30); (31); (33); (35), (37); (39); (40); (41); (42); (43); (44); (45); (46); (47); (48); (49); (50); (51); or a mixture of two or more thereof, wherein the grade is based on the classification described by  Scrap Specifications Circular  2003, pages 22-25, Institute of Scrap Recycling Industries, Inc.  
     
     
         5 . The method of  claim 1 , wherein the recycled pulp is relatively pure recycled pulp.  
     
     
         6 . A method for making recycled pulp comprising: 
 (a) providing waste material that comprises waste paper and, optionally, prohibitives;    (b) adding the waste material to a liquid-based fiber separator apparatus to produce the recycled pulp;    (c) removing liquid from the recycled pulp to produce recycled pulp that has a solids content from about 30 wt % to about 85 wt %.    
     
     
         7 . The method of  claim 6 , wherein the recycled pulp has a solids content from about 45 wt % to about 70 wt %.  
     
     
         8 . The method of  claim 6 , wherein the waste paper comprises a pulp substitute, a de-inking grade, a brown kraft grade, mixed waste paper, or a mixture of two or more thereof.  
     
     
         9 . The method of  claim 6 , wherein the waste paper comprises one or more grades selected from (1); (2); (4); (5); (6); (7); (8); (9); (10); (11); (12); (13); (15); (16); (17); (18); (19); (20); (21); (22); (23); (24); (25); (26); (27); (28); (30); (31); (33); (35); (37); (39); (40); (41); (42); (43); (44); (45); (46); (47); (48); (49); (50); (51); or a mixture of two or more thereof, wherein the grade is based on the classification described by  Scrap Specifications Circular  2003, pages 22-25, Institute of Scrap Recycling Industries, Inc.  
     
     
         10 . A method for providing recycled pulp to a paper mill comprising: 
 (a) providing waste material that comprises waste paper and, optionally, prohibitives;    (b) adding the waste material to a liquid-based fiber separator apparatus to produce the recycled pulp, wherein the recycled pulp is in a form that does not need to be re-pulped for further processing into paper or a paper product; and    (c) transporting the recycled pulp to a paper mill.    
     
     
         11 . The method of  claim 10 , further comprising removing liquid from the recycled pulp, wherein the recycled pulp is in a form that does not need to be re-pulped for further processing into paper or a paper product.  
     
     
         12 . The method of  claim 10 , further comprising storing the recycled pulp in a container prior to transporting the recycled pulp to a paper mill.  
     
     
         13 . The method of  claim 10 , wherein the waste paper comprises a pulp substitute, a de-inking grade, a brown kraft grade, mixed waste paper, or a mixture of two or more thereof.  
     
     
         14 . The method of  claim 10 , wherein the waste paper comprises one or more grades selected from (1); (2); (4); (5); (6); (7); (8); (9); (10); (11); (12); (13); (15); (16); (17); (18); (19); (20); (21); (22); (23); (24); (25); (26); (27); (28); (30); (31); (33); (35); (37); (39); (40); (41); (42); (43); (44); (45); (46); (47); (48); (49); (50); (51); or a mixture of two or more thereof, wherein the grade is based on the classification described by  Scrap Specifications Circular  2003, pages 22-25, Institute of Scrap Recycling Industries, Inc.  
     
     
         15 . A method for producing a recycled paper product comprising: 
 (a) providing waste material that comprises waste paper and, optionally, prohibitives;    (b) adding the waste material to a liquid-based fiber separator apparatus to produce the recycled pulp, wherein the recycled pulp is in a form that does not need to be re-pulped for further processing into paper or a paper product;    (c) transporting the recycled pulp to a paper mill; and    (d) mixing the recycled pulp with virgin pulp to produce the recycled paper product.    
     
     
         16 . The method of  claim 15 , wherein the recycled pulp that is in a form that does not need to be re-pulped for further processing is recycled pulp having a solids content of at least about 30 wt %.  
     
     
         17 . The method of  claim 16 , wherein the recycled pulp has a solids content from about 30 wt % to about 85 wt %.  
     
     
         18 . The method of  claim 15 , wherein the recycled pulp is relatively pure recycled pulp.  
     
     
         19 . The method of  claim 15 , wherein the waste paper comprises a pulp substitute, a de-inking grade, a brown kraft grade, mixed waste paper, or a mixture of two or more thereof.  
     
     
         20 . The method of  claim 15 , wherein the waste paper comprises one or more grades selected from (1); (2); (4); (5); (6); (7); (8); (9); (10); (11); (12); (13); (15); (16); (17); (18); (19); (20); (21); (22); (23); (24); (25); (26); (27); (28); (30); (31); (33); (35); (37); (39); (40); (41); (42); (43); (44); (45); (46); (47); (48); (49); (50); (51); or a mixture of two or more thereof, wherein the grade is based on the classification described by  Scrap Specifications Circular  2003, pages 22-25, Institute of Scrap Recycling Industries, Inc.