Wet oxidation of biomass

• US 9,458,569 B2
• Filed: 01/16/2014
• Issued: 10/04/2016
• Est. Priority Date: 01/16/2013
• Status: Active Grant

• Current Assignee: Clean-Vantage LLC
• Original Assignee: Clean-Vantage LLC
• Inventors: Merrill, Richard Alan, Petersen, Kenn
• Primary Examiner(s): Paguio Frising, Michelle F
• Application Number:
  US14/157,518
• Publication Number:
  US 20140199740A1
• Time in Patent Office: 992 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: C02F 11/08 Wet air oxidation
• CPC Class Codes: C02F 2103/28 from the paper or cellulose industry
• CPC Class Codes: C02F 2209/001 Upstream control, i.e. monitoring for predictive control
• CPC Class Codes: C02F 2209/03 Pressure
• CPC Class Codes: C02F 2209/06 pH
• CPC Class Codes: C02F 2209/225 in the gas phase
• CPC Class Codes: C02F 3/006 Regulation methods for biological treatment
• CPC Class Codes: C08H 6/00 Macromolecular compounds derived from lignin, e.g. tannins, humic acids
• CPC Class Codes: C08H 8/00 Macromolecular compounds derived from lignocellulosic materials pretreatment thereof B27N
• CPC Class Codes: C12P 2201/00 Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis
• CPC Class Codes: C12P 2203/00 Fermentation products obtained from optionally pretreated or hydrolyzed cellulosic or lignocellulosic material as the carbon source ethanol C12P7/10
• CPC Class Codes: D21C 1/02 with water or steam
• CPC Class Codes: D21C 1/08 with oxygen-generating compounds
• CPC Class Codes: D21C 11/0007 Recovery of by-products, i.e. compounds other than those necessary for pulping, for multiple uses or not otherwise provided for volatile compounds obtained by decomposition of spent liquors in order to regenerate them D21C11/125; compounds obtained by fractionating the liquors in order to regenerate them D21C11/0042
• CPC Class Codes: D21C 3/045 in presence of O2 or O3

Abstract

The present disclosure comprises methods, apparatus, components, and techniques for pretreatment of biomaterials using targeted wet oxidation. The targeted wet oxidation pretreatment is an upstream method for converting solid biomass into fuels and/or specialty chemicals. Embodiments of the present disclosure comprise methods carried out on biomaterials to selectively oxidize lignin components of the biomass, thereby resulting in bio accessible/digestible biomass fibers. In embodiments of the present disclosure, such methods may comprise pretreatment processes to prepare the biomaterials for a subsequent fermentation or other like conversion may be carried out to result in useful bio fuels or other bioproducts.

Claims

1. A method of pretreating a biomass slurry in a continuous process, comprising:

in the continuous process, obtaining a dry matter content of the biomass slurry of 15-60% by weight;

in the continuous process, introducing a flow of steam to a reaction chamber containing the biomass slurry;

while introducing the flow of steam to the reaction chamber, introducing a flow of oxygen to the reaction chamber and the biomass slurry, thereby causing oxidation of a lignin component of the biomass slurry; and

in the continuous process, flashing the biomass to a secondary holding unit by utilizing a pressure difference.

2. The method of claim 1, wherein obtaining a dry matter content of the biomass slurry of between 15-60% further comprises feeding the biomass slurry into a screw press.

3. The method of claim 1, wherein obtaining a dry matter content of the biomass slurry of 15-60% by weight further comprises introducing steam into the biomass slurry.

4. The method of claim 1, wherein obtaining a dry matter content of the biomass slurry of 15-60% by weight further comprises obtaining a dry matter content of 25-55% by weight.

5. The method of claim 1, wherein obtaining a dry matter content of the biomass slurry of 15-60% by weight further comprises obtaining a dry matter content of 30-50% by weight.

6. The method of claim 1, further comprising:

in the continuous process, preconditioning the biomass slurry by extracting a nontargeted substance from the biomass slurry.

7. The method of claim 6, wherein the nontargeted substance comprises xylan.

8. The method of claim 6, wherein preconditioning the biomass slurry comprises soaking the biomass with water having a temperature between 60 and 90 degrees Celsius.

9. The method of claim 1, further comprising an anaerobic digestion pre-processing operation.

10. The method of claim 1, wherein following oxidation of the lignin component of the biomass slurry, the biomass slurry is subjected to a fermentation operation.

11. The method of claim 1, further comprising venting carbon dioxide from the reaction chamber to maintain the amount of available oxygen within the reaction chamber at 0.01-15% of chemical oxygen demand.

12. The method of claim 11, wherein venting carbon dioxide from the reaction chamber to maintain the amount of added oxygen within the reaction chamber at 0.01 to 15% of chemical oxygen demand further comprises venting carbon dioxide from the reaction chamber to maintain the amount of added oxygen within the reaction chamber at 0.1 to 10% of chemical oxygen demand.

13. A method of oxidizing lignin components in a biomass slurry, comprising:

in a continuous process, removing water from the biomass slurry to achieve a dry matter content of 15-60% by weight;

in the continuous process, concurrently subjecting the biomass slurry to a stream of oxygen and a stream of steam; and

in the continuous process, flashing the biomass to a secondary holding unit by utilizing a pressure difference.

14. The method of claim 13, wherein the stream of steam is at a temperature of 110 to 260 degrees Celsius.

15. The method of claim 13, wherein removing water from the biomass slurry to achieve a dry matter content of 15-60% by weight comprises passing the biomass slurry through a screw press.

16. The method of claim 13, further comprising venting carbon dioxide from the biomass slurry.