Fiberboards, uses and methods of preparation thereof
View Patent ↗There is provided a fiberboard, such as a MDF fiberboard or a HDF fiberboard, comprising wood fibers, a binder, and a sludge such as a pulp and a paper sludge. The sludge can be, for example, chosen from a primary pulp and paper sludge, a secondary pulp and paper sludge, a de-inking sludge, and mixtures thereof.
1. A fiberboard comprising:
wood fibers;
a binder present in said fiberboard in an amount of about 18% or less by weight, based on the total dry weight of the fiberboard; and
an untreated sludge chosen from a primary pulp and paper sludge, a secondary pulp and paper sludge, and mixtures thereof,
wherein said fiberboard is a medium density fiberboard or a high density fiberboard having a density of about 500 to about 1000 kg/m 3 .
2. The fiberboard of claim 1 , wherein said wood fibers are virgin wood fibers, post-consumption wood fibers, or a mixture thereof.
3. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of at least 1% by weight, based on the total dry weight of the fiberboard.
4. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of at least 5% by weight, based on the total dry weight of the fiberboard.
5. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of at least 10% by weight, based on the total dry weight of the fiberboard.
6. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of about 1% to about 40% by weight, based on the total dry weight of the fiberboard.
7. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of about 1% to about 15% by weight, based on the total dry weight of the fiberboard.
8. The fiberboard of claim 1 , wherein said sludge is a primary pulp and paper sludge.
9. The fiberboard of claim 1 , wherein said sludge is a mixture of primary pulp and paper sludge and a secondary pulp and paper sludge.
10. The fiberboard of claim 1 , wherein said sludge is an untreated primary sludge taken from a paper mill.
11. The fiberboard of claim 1 , wherein said fiberboard has an internal bond strength of at least 1.30 N/mm 2 .
12. The fiberboard of claim 3 , wherein said fiberboard has an internal bond strength of at least 1.40 N/mm 2 .
13. The fiberboard of claim 1 , wherein said fiberboard has an internal bond strength of at least 1.70 N/mm 2 .
14. The fiberboard of claim 1 , wherein said fiberboard has an internal bond strength of at least 1.90 N/mm 2 .
15. The fiberboard of claim 7 , wherein said fiberboard has an internal bond strength of about 1.3 N/mm 2 to about 1.98 N/mm 2 .
16. The fiberboard of claim 15 , wherein said fiberboard has a density of about 800 kg/m 3 to about 1000 kg/m 3 .
17. The fiberboard of claim 1 , wherein said fiberboard has a density of about 900 kg/m 3 to about 1000 kg/m 3 .
18. The fiberboard of claim 1 , wherein said fiberboard has a density of about 800 kg/m 3 to about 950 kg/m 3 .
19. The fiberboard of claim 1 , wherein said binder is chosen from formaldehyde-based resins, isocyanate-based resins, and mixtures thereof.
20. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of 15% or less by weight, based on the total dry weight of the fiberboard.
21. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of about 2% to about 10% by weight, based on the total dry weight of the fiberboard.
22. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of about 5% by weight, based on the total dry weight of the fiberboard.
23. The fiberboard of claim 1 , wherein said sludge is present in said fiberboard in an amount of about 10% by weight, based on the total dry weight of the fiberboard.
24. The fiberboard of claim 20 , wherein said fiberboard has a density of about 800 kg/m 3 to about 1000 kg/m 3 .
25. The fiberboard of claim 24 , wherein said binder is present in said fiberboard in an amount of about 15% or less by weight, based on the total dry weight of the fiberboard.
26. The fiberboard of claim 24 , wherein said binder is present in said fiberboard in an amount of about 12.5% or less by weight, based on the total dry weight of the fiberboard.