权利要求：
CA 03127344 2021-07-20 WO 2020/160565 PCT/US2020/024093 CLAIMS What is claimed is: 1. A nanocellulose-slurry dewatering system comprising: a nanocellulose slurry feed sub-system, wherein said nanocellulose slurry comprises nanocellulose and water; an inlet for a dispersion/drying agent; a twin-screw extruder in flow communication with said nanocellulose slurry feed sub-system, wherein said twin-screw extruder is configured for intimately mixing said nanocellulose slurry and said dispersion/drying agent, and wherein said twin- screw extruder is configured with one or more extruder vents to remove at least a portion of said water from said nanocellulose slurry; an extruder outlet for recovering a nanocellulose-dispersion concentrate comprising said nanocellulose and said dispersion/drying agent; and an optional milling device configured to generate a powder containing said nanocellulose-dispersion concentrate.
2. The nanocellulose-slurry dewatering system of claim 1, wherein said nanocellulose slurry feed sub-system is configured with an internal rotating agitator and/or wiping blade to mix said nanocellulose slurry.
3. The nanocellulose-slurry dewatering system of claim 1, wherein said nanocellulose-slurry dewatering system comprises a mixing unit configured for mixing said nanocellulose slurry with said dispersion/drying agent.
4. The nanocellulose-slurry dewatering system of claim 1, wherein said nanocellulose-slurry dewatering system comprises a nanocellulose slurry pre- concentration unit configured to remove at least a portion of said water from said nanocellulose slurry prior to water removal in said extruder.
5. The nanocellulose-slurry dewatering system of claim 4, wherein said nanocellulose slurry pre-concentration unit is a centrifuge. CA 03127344 2021-07-20 WO 2020/160565 PCT/US2020/024093
6. The nanocellulose-slurry dewatering system of claim 4, wherein said nanocellulose slurry pre-concentration unit is a filtration device.
7. The nanocellulose-slurry dewatering system of claim 4, wherein said inlet for said dispersion/drying agent is an inlet to said nanocellulose slurry pre- concentration unit.
8. The nanocellulose-slurry dewatering system of claim 1, wherein said twin- screw extruder is a co-rotating twin-screw extruder.
9. The nanocellulose-slurry dewatering system of claim 1, wherein said twin- screw extruder is a counter-rotating twin-screw extruder.
10. The nanocellulose-slurry dewatering system of claim 1, wherein said optional milling device is present.
11. A nanocellulose-slurry dewatering system comprising: a nanocellulose slurry feed sub-system, wherein said nanocellulose slurry comprises nanocellulose and water; an inlet for a dispersion/drying agent; a twin-rotor mixer in communication with said nanocellulose slurry feed sub- system, wherein said twin-rotor mixer is configured for intimately mixing said nanocellulose slurry and said dispersion/drying agent, and wherein said twin- rotor mixer is configured with one or more mixer vents to remove at least a portion of said water from said nanocellulose slurry; and an optional milling device configured to generate a powder containing said nanocellulose-dispersion concentrate.
12. The nanocellulose-slurry dewatering system of claim 11, wherein said inlet for said dispersion/drying agent is an inlet to said nanocellulose slurry feed sub- system. CA 03127344 2021-07-20 WO 2020/160565 PCT/US2020/024093
13. The nanocellulose-slurry dewatering system of claim 11, wherein said nanocellulose-slurry dewatering system comprises a mixing unit configured for mixing said nanocellulose slurry with said dispersion/drying agent.
14. The nanocellulose-slurry dewatering system of claim 11, wherein said nanocellulose-slurry dewatering system comprises a nanocellulose slurry pre- concentration unit configured to remove at least a portion of said water from said nanocellulose slurry prior to water removal in said twin-rotor mixer.
15. The nanocellulose-slurry dewatering system of claim 14, wherein said nanocellulose slurry pre-concentration unit is a centrifuge.
16. The nanocellulose-slurry dewatering system of claim 14, wherein said nanocellulose slurry pre-concentration unit is a filtration device.
17. The nanocellulose-slurry dewatering system of claim 14, wherein said inlet for said dispersion/drying agent is an inlet to said nanocellulose slurry pre- concentration unit.
18. The nanocellulose-slurry dewatering system of claim 11, wherein said twin-rotor mixer is a co-rotating twin-rotor mixer.
19. The nanocellulose-slurry dewatering system of claim 11, wherein said twin-rotor mixer is a counter-rotating twin-rotor mixer.
20. The nanocellulose-slurry dewatering system of claim 11, wherein said optional milling device is present. CA 03127344 2021-07-20 WO 2020/160565 PCT/US2020/024093 21. A method to dewater a nanocellulose slurry, said method comprising: (a) providing a nanocellulose slurry comprising nanocellulose and water; (b) providing a dispersion/drying agent that is selected for compatibility with said nanocellulose; (c) in a twin-screw system, intimately mixing said nanocellulose slurry and said dispersion/drying agent; (d) in said twin-screw system, removing at least a portion of said water from said nanocellulose slurry via one or more system vents, to generate a nanocellulose- dispersion concentrate; (e) optionally milling said nanocellulose-dispersion concentrate to generate a powder; and (f) recovering said nanocellulose-dispersion concentrate in solid form or liquid form.
22. .. The method of claim 21, wherein said nanocellulose slurry is pre- concentrated in a nanocellulose slurry pre-concentration step to remove at least a portion of said water from said nanocellulose slurry, prior to step (c).
23. .. The method of claim 22, wherein said nanocellulose slurry pre- concentration step is centrifugation.
24. .. The method of claim 22, wherein said nanocellulose slurry pre- concentration step is filtration.
25. The method of claim 21, wherein said dispersion/drying agent is selected from the group consisting of waxes, polyolefins, olefin¨maleic anhydride copolymers, olefin¨ acrylic acid copolymers, polyols, fatty acids, fatty alcohols, polyol¨glyceride esters, polydimethylsiloxanes, polydimethylsiloxane¨alkyl esters, polyacrylamides, starches, cellulose derivatives, particulates, and combinations or reaction products thereof
26. The method of claim 21, wherein said dispersion/drying agent is added to said nanocellulose slurry prior to step (c). CA 03127344 2021-07-20 WO 2020/160565 PCT/US2020/024093
27. The method of claim 21, wherein said twin-screw system is operated with an average temperature from about 120 C to about 300 C.
28. The method of claim 21, wherein said twin-screw system is operated with maximum system temperature that is less than the thermal-decomposition onset temperature of said nanocellulose.
29. The method of claim 21, wherein said twin-screw system is operated with maximum system temperature that is less than the thermal-decomposition onset temperature of said dispersion/drying agent.
30. The method of claim 21, wherein said twin-screw system is a twin-screw extruder containing a plurality of extruder zones, and wherein zone temperatures for each of said extruder zones are independently controlled.
31. The method of claim 30, wherein said zone temperatures increase along the length of said twin-screw extruder.
32. The method of claim 21, wherein at least one of said system vents is operated under vacuum.
33. The method of claim 32, wherein step (d) utilizes multiple system vents, and wherein each of said system vents is operated under vacuum.
34. The method of claim 21, wherein said nanocellulose is present at a concentration of about 10 wt% to about 90 wt% in said nanocellulose-dispersion concentrate.
35. The method of claim 21, wherein said dispersion/drying agent is present at a concentration of about 5 wt% to about 65 wt% in said nanocellulose-dispersion concentrate.
36. The method of claim 21, wherein said nanocellulose includes cellulose nanocrystals, cellulose nanofibrils, microfibrillated cellulose, or a combination thereof. CA 03127344 2021-07-20 WO 2020/160565 PCT/US2020/024093
37. The method of claim 21, wherein said nanocellulose includes lignin- containing nanocellulose.
38. The method of claim 21, wherein said nanocellulose includes lignin- coated nanocellulose.
39. The method of claim 21, wherein said method is continuous or semi- continuous.
40. The method of claim 21, wherein said method is a batch process.