Process of transforming waste material into useful material
In a process for transforming waste material into useful material, a quantity of waste material such as household garbage or municipal solid waste is provided. The waste material is pre-shredded into pre-shredded waste material. The pre-shredded waste material is processed to at least partially remove one or more selected material components, thereby providing a processed pre-shredded waste material. The processed pre-shredded waste material is then secondarily shredded into secondarily shredded waste material which is then hydrolyzed under pressure greater than ambient pressure to create an aggregate cellulose pulp.
1. A process for transforming waste material into useful material, the process comprising steps of:
(a) providing a quantity of waste material;
(b) pre-shredding the waste material into pre-shredded waste material having a nominal maximum piece size of at least about 6 inches;
(c) processing the pre-shredded waste material to at least partially remove one or more selected material components, thereby providing a processed pre-shredded waste material;
(d) secondarily shredding the processed pre-shredded waste material into a secondarily shredded waste material having a nominal maximum piece size no greater than about 2 inches; and
(e) hydrolyzing the secondarily shredded waste material under pressure greater than ambient pressure to create an aggregate cellulose pulp.
2. The process of claim 1 , wherein:
in step (b) the waste material is pre-shredded into pre-shredded waste material having a nominal maximum piece size of at least about 8 inches.
3. The process of claim 2 , wherein:
in step (d) the secondarily shredded waste material has a nominal maximum piece size no greater than about 1 inch.
4. The process of claim 1 , wherein the processing step (c) further comprises:
separating the pre-shredded waste material into a smaller piece stream and larger piece stream with a primary separator.
5. The process of claim 4 , wherein the processing step (c) further comprises:
downstream of the primary separator, separating the smaller piece stream into heavier piece stream and a lighter piece stream.
6. The process of claim 4 , wherein:
the smaller piece stream has a nominal maximum piece size in a range of from about 1 inch to about 3 inches.
7. The process of claim 6 , wherein the processing step (c) further comprises:
upstream of the primary separator, separating ferrous material from the pre-shredded waste material.
8. The process of claim 6 , wherein the processing step (c) further comprises:
downstream of the primary separator separating at least a portion of the larger piece stream with a 2D/3D separator into a stream of substantially two-dimensional pieces and a stream of substantially three-dimensional pieces.
9. The process of claim 8 wherein the processing step (c) further comprises:
downstream of the primary separator and upstream of the 2D/3D separator separating the larger piece stream into heavier piece stream and a lighter piece stream, the lighter piece stream being directed to the 2D/3D separator.
10. The process of claim 9 wherein the processing step (c) further comprises:
separating the heavier piece stream into an organics stream comprising primarily organic material and an inorganics stream comprising primarily inorganic material with an organic/inorganic separator.
11. The process of claim 10 , further comprising:
processing the organic stream in an anaerobic digester.
12. The process of claim 10 , wherein:
the organic/inorganic separator includes a water bath separator configured to float the organic material away from the inorganic material.
13. The process of claim 10 , wherein the processing step (c) further comprises:
directing the organic stream to the secondary shredder.
14. The process of claim 9 , wherein the processing step (c) further comprises:
upstream of the secondary shredder, separating ferrous material from a material stream otherwise entering the secondary shredder.
15. The process of claim 9 wherein the processing step (c) further comprises:
removing polyvinylchloride (PVC) pieces from the stream of substantially three-dimensional pieces from the 2D/3D separator.
16. The process of claim 9 wherein the processing step (c) further comprises:
removing non-ferrous metal pieces from the stream of substantially three-dimensional pieces from the 2D/3D separator.