Processing biomass

Patent metadata

Field	Value
Publication number	US-9321850-B2
Application number	US-201414579926-A
Country	US
Kind code	B2
Filing date	Dec 22, 2014
Priority date	Nov 17, 2008
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

Methods are provided for reducing one or more dimensions of individual pieces of biomass; treating biomass, such as size-reduced biomass; changing a molecular structure of a biomass material; and, optionally, subjecting the biomass to a primary process to form a product. The methods include processing biomass materials using a screw extrusion process, and treating the biomass material with a screw extrusion process in size-reduction and treating steps.

First claim

What is claimed is:

1. A method of processing biomass materials using a screw extrusion process, the method comprising:
conveying biomass material through a screw extruder comprising a co-extruder having a first barrel and a second barrel, wherein the conveying step comprises conveying a first biomass material through the first barrel and conveying a second biomass material through the second barrel;
applying compression and shear forces via a plurality of interpenetrate helicoidal surfaces within the screw extruder, the forces effective to reduce one or more dimensions of individual pieces of biomass material;
exposing the biomass material to a plurality of scanning electron beam emitters while conveying the biomass material through the screw extruder, the scanning electron beam emitters each effecting a desired dose of electron beam radiation, wherein the exposing step comprises exposing the first biomass material to a first dose of electron beam irradiation and exposing the second biomass material to a second dose of electron beam irradiation; and
producing an extrudate comprising the material discharged from the screw extrusion process.

2. The method of claim 1 , wherein the first biomass material differs from the second biomass material prior to introduction to the screw extruder.

3. The method of claim 2 , wherein the first biomass material differs from the second biomass material by virtue of one or more of the following characteristics: source of biomass material, type of biomass material, level of recalcitrance, average molecular weight, average crystallinity, surface area, average fiber length, average length-to-diameter ratio, average BET surface area, bulk density, degree of polymerization, porosity, degree of branching, degree of grafting, domain size of the biomass material, and molecular make-up of the biomass material.

4. The method of claim 2 , wherein the individual pieces of biomass of the first biomass material have one or more dimensions which, on average, exceed the corresponding one or more dimensions of the individual pieces of biomass of the second biomass material.

5. The method of claim 2 , wherein the first dose of electron beam irradiation is greater than the second dose of electron beam irradiation.

6. The method of claim 5 , wherein the first dose of electron beam irradiation is at least 100 Mrad and the second dose of electron beam irradiation is at least 10 Mrad.

7. The method of claim 2 , wherein the first dose of electron beam irradiation is applied at a first dose rate and the second dose of electron beam irradiation is applied at a second dose rate, the first dose rate differing from the second dose rate.

8. The method of claim 7 , wherein the first dose rate is greater than the second dose rate.

9. The method of claim 2 , wherein conveying comprises selectively advancing the first biomass material through a plurality of apertures in the first barrel after a desired effect of the first barrel has been attained, and selectively advancing the second biomass material through a plurality of apertures in the second barrel after a desired effect of the second barrel has been attained, the desired effect of the first barrel differing from the desired effect of the second barrel.

10. The method of claim 9 , wherein the desired effect of the first barrel and the desired effect of the second barrel each comprises a change in one or more of: level of recalcitrance, average molecular weight, average crystallinity, surface area, average fiber length, average length-to-diameter ratio, average BET surface area, bulk density, degree of polymerization, porosity, degree of branching, degree of grafting, domain size of the biomass material, and molecular make-up of the biomass material.

11. The method of claim 2 , wherein the extrudate comprises a multi-layer composite, the composite having a first layer formed from the material discharged from the first barrel and a second layer formed from the material discharged from the second barrel.

12. The method of claim 2 , wherein the screw extrusion process comprises one or more of the following elements: a mixing element, a pulverizing element, and a kneading element; and the one or more elements are effective to provide a homogeneous extrudate comprising the material discharged from the first barrel and the material discharged from the second barrel.

13. The method of claim 1 , wherein the first biomass material and the second biomass material are derived from the same source.

14. The method of claim 13 , wherein the first dose of electron beam irradiation is greater than the second dose of electron beam irradiation.

15. The method of claim 14 , wherein the first dose of electron beam irradiation is at least 100 Mrad and the second dose of electron beam irradiation is at least 10 Mrad.

16. The method of claim 13 , wherein the first dose of electron beam irradiation is applied at a first dose rate and the second dose of electron beam irradiation is applied at a second dose rate, the first dose rate differing from the second dose rate.

17. The method of claim 16 , wherein the first dose rate is greater than the second dose rate.

18. The method of claim 13 , wherein conveying comprises selectively advancing the first biomass material through a plurality of apertures in the first barrel after a desired effect of the first barrel has been attained, and selectively advancing the second biomass material through a plurality of apertures in the second barrel after a desired effect of the second barrel has been attained, the desired effect of the first barrel differing from the desired effect of the second barrel.

19. The method of claim 18 , wherein the desired effect of the first barrel and the desired effect of the second barrel each comprises a change in one or more of: level of recalcitrance, average molecular weight, average crystallinity, surface area, average fiber length, average length-to-diameter ratio, average BET surface area, bulk density, degree of polymerization, porosity, degree of branching, degree of grafting, domain size of the biomass material, and molecular make-up of the biomass material.

20. The method of claim 13 , wherein the extrudate comprises a multi-layer composite, the composite having a first layer formed from the material discharged from the first barrel and a second layer formed from the material discharged from the second barrel.

21. The method of claim 13 , wherein the screw extrusion process comprises one or more of the following elements: a mixing element, a pulverizing element, and a kneading element; and the one or more elements are effective to provide a homogeneous extrudate comprising the material discharged from the first barrel and the material discharged from the second barrel.

22. The method of claim 1 , wherein the first dose of electron beam irradiation and the second dose of electron beam irradiation are each provided at a dose rate of 1 Mrad per second to about 10 Mrad per second.

23. The method of claim 1 , wherein the first dose of electron beam irradiation and the second dose of electron beam irradiation are each between about 10 Mrad and about 150 Mrad.

Assignees

• Xyleco Inc

Inventors

• Medoff Marshall

Classifications

• B29B9/12

  characterised by structure or composition · CPC title

• C12Y302/01004

  Cellulase (3.2.1.4), i.e. endo-1,4-beta-glucanase · CPC title

• C12P2201/00

  Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis · CPC title

• C08B1/00 Primary

  Preparatory treatment of cellulose for making derivatives thereof {, e.g. pre-treatment, pre-soaking, activation} · CPC title

• B01J2219/0879

  Solid · CPC title