Methods to control organic contaminants in fibers
Methods to control organic contaminants in fibers are described. One method involves contacting the fibers with a composition containing water-soluble cellulose derivative and ester hydrolyzing enzyme, for a sufficient time and in a sufficient amount to control the organic contaminants present in the fibers. This method is effective to reduce stickies in paper mill furnish formed with recycled fibers. A method for pitch control in paper mill furnish formed with virgin fibers is also provided by the additional inclusion of lipoxygenase in the composition. Resulting paper products formed from the processed fibers are also described as well as methods to make them.
1. A method for controlling deposition of organic contaminants from fibers in paper making systems, comprising contacting said fibers with a composition comprising at least one water-soluble cellulose derivative and at least one ester hydrolyzing enzyme, for a sufficient time and in sufficient amount to control the organic contaminants present in the fibers.
2. The method of claim 1 , wherein said organic contaminants comprise synthetic polymers from adhesives, glues, hot-melts, coatings, coating binders, de-inking chemicals, ink residues, wood resins, rosin, contact adhesive binders, unpulped wet strength resins, pitch, or combinations thereof.
3. The method of claim 1 , wherein said fibers comprise recycled fibers.
4. The method of claim 3 , wherein said organic contaminants comprise stickies.
5. The method of claim 3 , wherein the ester hydrolyzing enzyme comprises lipase.
6. The method of claim 3 , wherein the water-soluble cellulose derivative is methyl cellulose, hydroxyl methyl cellulose, hydroxyethyl methyl cellulose, hydropropyl methyl cellulose, cetyl hydroxyethylcellulose or hydroxybutyl methyl cellulose, singly or in any combination thereof.
7. The method of claim 3 , wherein said fibers containing organic contaminants comprise fibers from old corrugated containers, old newsprint or old newspapers, mixed office waste, or any combinations thereof.
8. The method of claim 3 , wherein the organic contaminants are at least controlled by reducing the amount of organic contaminants present in the fiber.
9. The method of claim 3 , wherein the organic contaminants are at least controlled by reducing the size of the organic contaminants present in the fibers.
10. The method of claim 3 , wherein the organic contaminants are at least controlled by reducing the tackiness of the organic contaminants present in the fibers.
11. The method of claim 3 , wherein said composition is introduced prior to a pulping stage.
12. The method of claim 3 , wherein said composition is introduced during a pulping stage.
13. The method of claim 3 , wherein said composition is introduced during or right before a stock preparation stage.
14. The method of claim 3 , wherein said composition is introduced after a flotation or a de-inking stage.
15. The method of claim 3 , wherein said composition is introduced in an amount providing about 0.002 to about 2 lbs. water-soluble cellulose derivative per ton of dry fiber, and about 0.005 to about 4 lbs. ester hydrolyzing enzyme per ton dry fiber treated.
16. The method of claim 3 , wherein said composition is in contact with the fibers for a time of from about 1 minute to about 8 hours.
17. The method of claim 3 , further comprising forming said fibers into paper or paperboard products.
18. The method of claim 3 , wherein said composition is introduced prior to the paper machine headbox.
19. The method of claim 3 , wherein said composition is introduced in the paper machine white water.
20. The method of claim 1 , wherein said fibers comprises virgin fibers, said organic contaminants comprise pitch.
21. The method of claim 20 , wherein said composition further comprises lipoxygenase.
22. The method of claim 20 , wherein the ester hydrolyzing enzyme comprises esterase, lipase, or cutinase, singly or in any combination thereof.
23. The method of claim 20 , wherein the water-soluble cellulose derivative is methyl cellulose, hydroxyl methyl cellulose, hydroxyethyl methyl cellulose, hydropropyl methyl cellulose, cetyl hydroxyethylcellulose, or hydroxybutyl methyl cellulose, singly or in any combination thereof.
24. The method of claim 21 , wherein said composition is introduced in an amount providing about 0.002 to about 2 lbs. water-soluble cellulose derivative per ton of dry fiber treated, and about 0.005 to about 4 lbs. ester hydrolyzing enzyme per ton dry fiber treated, and about 0.004 to about 4 lbs. lipoxygenase per ton of dry fiber treated.
25. The method of claim 1 , wherein said water-soluble cellulose derivative is a methyl ether cellulose derivative.
26. The method of claim 1 , wherein the ester hydrolyzing enzyme comprises esterase, lipase, or cutinase, singly or in any combination thereof.