TWO STEP OPTIMIZATION FOR LIQUEFACTION OF BIOMASS

• US 20150122245A1
• Filed: 04/30/2013
• Published: 05/07/2015
• Est. Priority Date: 04/30/2012
• Status: Abandoned Application

• Current Assignee: Renmatix, Inc.
• Original Assignee: Reac Fuel AB (Renmatix, Inc.)
• Inventors: Jhannesson, Haukur, Gram, Andreas, Carlius, Anders, Karlsson, Gran
• Application Number:
  US14/397,805
• Publication Number:
  US 20150122245A1
• Time in Patent Office: Days
• US Class Current: 127/37
• CPC Class Codes: C07G 1/00 Lignin; Lignin derivatives
• CPC Class Codes: C12P 2201/00 Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis
• CPC Class Codes: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: C13K 1/04 Purifying
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

The present invention describes a process involving liquefaction of a biomass slurry by treatment in hot compressed water (HCW), said process comprising: —a first decomposition step being performed at an average pH level of at most 4.5, wherein a hemicellulose fraction in the biomass slurry is decomposed to water soluble mono- and/or oligomers, and wherein a cellulose fraction undergoes a pre-treatment for decrystallization of the cellulose polymer; —a separation step; and —a second decomposition step, wherein the cellulose fraction in the biomass slurry is decomposed to water soluble mono- and/or oligomers; wherein both of the first and second decomposition steps are performed at sub-critical temperatures implying relatively moderate conditions.

Claims

1. Process involving liquefaction of a biomass slurry by treatment in hot compressed water (HCW), said process comprising:

a first decomposition step being performed at an average pH level of at most 4.5, wherein a hemicellulose fraction in the biomass slurry is decomposed to water soluble mono- and/or oligomers, and wherein a cellulose fraction undergoes a pre-treatment for decrystallization of the cellulose polymer;

a separation step; and

a second decomposition step, wherein the cellulose fraction in the biomass slurry is decomposed to water soluble mono- and/or oligomers;

wherein both of the first and second decomposition steps are performed at sub-critical temperatures implying relatively moderate conditions.

2. Process according to claim 1, wherein the pre-treatment of the cellulose fraction in the first decomposition step implies that the cellulose matrix is converted to a less rigid structure.

3. Process according to claim 1 or 2, wherein the second decomposition step is performed at a higher average temperature than the first decomposition step.

4. Process according to any of claims 1-3, wherein the second decomposition step is performed at a higher average temperature than the first decomposition step and wherein the first decomposition step is performed at an average temperature of 200-270°

C. and the second decomposition step is performed at an average temperature of 250°

C.-340°

C.

5. Process according to claim 4, wherein the first decomposition step is performed at a temperature of 230-260°

C. and the second decomposition step is performed at a temperature of 300°

C.-340°

C.

6. Process according to claim 4 or 5, wherein the first decomposition step is performed at a temperature of 230-260°

C. during a time of from 5 to 30 seconds and the second decomposition step is performed at a temperature of 300°

C.-340°

C. during a time of 2-10 seconds.

7. Process according to any of claims 1-6, wherein the separation step involves filtration, sedimentation and/or decantation.

8. Process according to any of claims 1-7, wherein a temperature decrease is performed before or in connection with the separation step.

9. Process according to any of the preceding claims, wherein additional HCW or steam is added to the remaining biomass slurry before the second decomposition step.

10. Process according to any of the preceding claims, wherein a pH lowering additive is added in the process and the pH level of the solution is in the range of 1.0-3.5 after such addition of a pH lowering additive.

11. Process according to any of the preceding claims, wherein a pH lowering additive is added before the first decomposition step.

12. Process according to any of the preceding claims, wherein the process also involves a flash step(s), performed after the first decomposition step and/or after the second decomposition step, to reduce the temperature to 220°

C. or below in order to prevent continued decomposition and/or to increase the yield.

13. Process according to any of the preceding claims, wherein the process also involves a post-hydrolysis step where existing oligomers are converted to monomers.

14. Process according to any of the preceding claims, wherein a dispersing agent is added.

15. Process according to any of the preceding claims, wherein the biomass is a lignocellulosic biomass.

16. Process according to claim 15, wherein the process also comprises treating and/or collecting a lignin fraction from the biomass slurry.