Processing biomass

Patent metadata

Field	Value
Publication number	US-2016177358-A1
Application number	US-201615058033-A
Country	US
Kind code	A1
Filing date	Mar 1, 2016
Priority date	Nov 17, 2008
Publication date	Jun 23, 2016
Grant date	—

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 producing sugars using a screw extrusion process, the method comprising:
hydrolyzing one or more lignocellulosic materials with cellulase while conveying the one or more lignocellulosic materials through a screw extrusion process, the one or more lignocellulosic materials having been exposed to ionizing radiation; and discharging an extrudate from the screw extrusion process, the extrudate comprising one or more fermentable sugars released from cellulolytic hydrolysis of the one or more lignocellulosic materials.

2 . The method of claim 1 , wherein the one or more lignocellulosic materials have been subjected to a size-reduction process.

3 . The method of claim 2 , wherein the screw extrusion process comprises the size-reduction process.

4 . The method of claim 3 , wherein the size-reduction process comprises compression and shear forces applied via a plurality of interpenetrate helicoidal surfaces within a screw extruder, the forces effective to reduce one or more dimensions of individual pieces of lignocellulosic material.

5 . The method of claim 1 , wherein the screw extrusion process comprises the ionizing radiation.

6 . The method of claim 5 , wherein the ionizing radiation comprises exposing the one or more lignocellulosic materials to an ion beam while conveying the one or more lignocellulosic materials through a screw extruder, the ion beam effecting a desired dose of ionizing radiation.

7 . The method of claim 6 , wherein the dose of ionizing radiation received by the one or more lignocellulosic materials depends, at least in part, on the speed of the screw extruder.

8 . The method of claim 1 , wherein the degree of cellulolytic hydrolysis performed on the one or more lignocellulosic materials depends, at least in part, on the speed of a screw extruder in the screw extrusion process.

9 . The method of claim 1 , wherein conveying comprises selectively advancing the one or more lignocellulosic materials through a plurality of apertures after a desired effect of the screw extrusion process has been attained.

10 . The method of claim 9 , wherein the desired effect 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 lignocellulosic material, and molecular make-up of the lignocellulosic material.

11 . The method of claim 1 , wherein the screw extrusion process comprises controlling the temperature of the lignocellulosic material within one or more zones by means of controlled heating or cooling.

12 . The method of claim 1 , 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.

13 . The method of claim 1 , wherein the screw extrusion process comprises a co-extruder having a first barrel and a second barrel; and conveying comprises conveying a first lignocellulosic material through the first barrel and conveying a second lignocellulosic material through the second barrel; and hydrolyzing comprises exposing the first lignocellulosic material to a first hydrolysis process and exposing the second lignocellulosic material to a second hydrolysis process.

14 . The method of claim 13 , wherein the first lignocellulosic material differs from the second lignocellulosic material prior to introduction to the co-extruder.

15 . The method of claim 14 , wherein the first lignocellulosic material differs from the second lignocellulosic material in respect of one or more of the following characteristics: source of lignocellulosic material, type of lignocellulosic 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 lignocellulosic material, and molecular make-up of the lignocellulosic material.

16 . The method of claim 14 , wherein the individual pieces of the first lignocellulosic material have one or more dimensions which, on average, exceed the corresponding one or more dimensions of the individual pieces of the lignocellulosic material.

17 . The method of claim 13 , wherein hydrolyzing the first lignocellulosic material yields a first hydrolyzed material, and hydrolyzing the second lignocellulosic material yields a second hydrolyzed material, the first hydrolyzed material differing from the second hydrolyzed material in respect of the concentration of the one or more fermentable sugars.

18 . The method of claim 17 , wherein the one or more fermentable sugars comprise glucose, xylose, arabinose, mannose, galactose, oligosaccharides, polysaccharides, or mixtures of these.

19 . The method of claim 14 , wherein the first lignocellulosic material has received a first dose of ionizing radiation and the second lignocellulosic material has received a second dose of ionizing radiation, the first dose of ionizing radiation being greater than the second dose of ionizing radiation.

20 . The method of claim 19 , wherein the first dose of ionizing radiation is applied at a first dose rate and the second dose of ionizing radiation is applied at a second dose rate, the first dose rate differing from the second dose rate.

21 . The method of claim 20 , wherein the first dose rate is greater than the second dose rate.

22 . The method of claim 14 , wherein conveying comprises selectively advancing the first lignocellulosic 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 lignocellulosic 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.

23 . The method of claim 22 , 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 lignocellulosic material, and molecular make-up of the lignocellulosic material.

24 . The method of claim 22 , wherein the desired effect of the first barrel comprises a concentration of a fermentable sugar released from cellulolytic hydrolysis of the first lignocellulosic material and the desired effect of the second barrel comprises a concentration of a fermentable sugar released from cellulolytic hydrolysis of the second lignocellulosic material.

25 . The method of claim 14 , 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.

26 . The method of claim 14 , wherein the screw ex

Assignees

• Xyleco Inc

Inventors

• Medoff Marshall

Classifications

• C12P2201/00

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

• C12Y302/01004

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

• B29K2001/00

  Use of cellulose, modified cellulose or cellulose derivatives, e.g. viscose, as moulding material · CPC title

• C10L5/44

  on vegetable substances · CPC title

• C12P19/02

  Monosaccharides (2-ketogulonic acid C12P7/60) · CPC title