Non-pressurised pre-treatment, enzymatic hydrolysis and fermentation of waste fractions

• US 9,914,944 B2
• Filed: 09/29/2006
• Issued: 03/13/2018
• Est. Priority Date: 09/30/2005
• Status: Active Grant

• Current Assignee: Renescience A/S
• Original Assignee: Renescience A/S
• Inventors: Nrholm, Nanna Dreyer, Larsen, Jan, Iversen, Frank Krogh
• Primary Examiner(s): McDonald, Jennifer Pitrak
• Assistant Examiner(s): Xu, Qing
• Application Number:
  US12/088,431
• Publication Number:
  US 20090004714A1
• Time in Patent Office: 4,183 Days
• Field of Search: 435163, 435165
• CPC Class Codes: B09B 3/00 Destroying solid waste or transforming solid waste into something useful or harmless
• CPC Class Codes: B09B 3/45 Steam treatment, e.g. supercritical water gasification or oxidation
• CPC Class Codes: C12M 27/02 Stirrer or mobile mixing elements
• CPC Class Codes: C12M 27/06 with horizontal or inclined stirrer shaft or axis
• CPC Class Codes: C12M 27/24 Draft tube C12M29/08 takes precedence
• CPC Class Codes: C12M 45/04 Phase separators; Separation of non fermentable material; Fractionation
• CPC Class Codes: C12M 45/06 by chemical means or hydrolysis
• CPC Class Codes: C12M 45/20 Heating; Cooling heating or cooling apparatus for laboratory uses B01L7/00
• CPC Class Codes: C12N 9/20 Triglyceride splitting, e.g. by means of lipase
• CPC Class Codes: C12N 9/2411 Amylases
• CPC Class Codes: C12N 9/2437 Cellulases (3.2.1.4; 3.2.1.74; 3.2.1.91; 3.2.1.150)
• CPC Class Codes: C12N 9/2477 Hemicellulases not provided in a preceding group
• CPC Class Codes: C12N 9/48 acting on peptide bonds (3.4)
• CPC Class Codes: C12P 19/00 Preparation of compounds containing saccharide radicals ketoaldonic acids C12P7/58
• CPC Class Codes: C12P 7/06 Ethanol, i.e. non-beverage
• CPC Class Codes: C12P 7/10 substrate containing cellulosic material
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel

Abstract

The present invention relates to a process for production of fermentation products, including bioethanol by non-pressurized pre-treatment, enzymatic hydrolysis and fermentation of waste fractions containing mono- and/or polysaccharides, having a relatively high dry matter content. The process in its entirety, i.e. from non-pressurized pre-treatment over enzymatic hydrolysis and fermentation to sorting of fermentable and non-fermentable solids can be processed at a relatively high dry matter content in a single vessel or similar device using free fall mixing for the mechanical processing of the waste fraction.

Claims

1. A method of sorting fermentable parts of unsorted municipal solid waste (MSW) from non-fermentable solids comprising

subjecting unsorted MSW derived from households to non-pressurized thermal pretreatment, followed by enzymatic hydrolysis of said unsorted MSW so as to liquefy fermentable parts of the unsorted MSW and thereby produce liquefied fermentable parts of the unsorted MSW, followed by

sorting of the liquefied fermentable parts of the unsorted MSW from non-fermentable solids,

wherein the liquefied fermentable parts of the unsorted MSW are subsequently subjected to fermentation, and

wherein the non-pressurized thermal pretreatment and enzymatic hydrolysis are carried out in a single vessel using free fall mixing to mechanically process the unsorted MSW.

2. The method according to claim 1, wherein said fermentation is anaerobic fermentation.

3. The method according to claim 1, wherein said fermentation is conducted with an ethanologenic microorganism.

4. The method according to claim 1, wherein said fermentation comprises addition of nitrogen sources.

5. The method according to claim 1, wherein said fermentation comprises addition of nutrients or vitamins.

6. The method according to claim 1, wherein the non-pressurised thermal pre-treatment is performed in the presence of steam.

7. The method according to claim 1, wherein the non-pressurised thermal pre-treatment is conducted for a time period up to 120 min. at a temperature range between 60-110°

C. and with a steam admission of 0-2 kg/kg dry matter.

8. The method according to claim 1, wherein the enzymatic hydrolysis lasts for a time period up to 96 hours and with a temperature ranging from 20-105°

C.

9. The method according to claim 1, wherein the enzymatic hydrolysis is conducted using a mixture of enzymes including cellulases, cellobiolases, and hemicellulases.

10. The method according to claim 1, wherein said enzymatic hydrolysis comprises introducing a mixture of enzymes including proteolytic enzymes.

11. The method according to claim 1, wherein said enzymatic hydrolysis comprises introducing a mixture of enzymes including alpha amylases and glyco amylases.

12. The method according to claim 1, wherein said enzymatic hydrolysis comprises introducing a mixture of enzymes including lipases.

13. The method according to claim 1, wherein said enzymatic hydrolysis comprises introducing a mixture of enzymes including oxidative enzymes.

14. The method according to claim 1, wherein the sorting of the liquefied fermentable parts of the unsorted MSW from the non-fermentable solids is performed by a sieve system.

15. The method according to claim 1, wherein the dry matter content of the unsorted MSW during the enzymatic hydrolysis is 20-45% w/w.

16. The method according to claim 1, wherein the unsorted MSW is subjected to mechanical pre-treatment prior to the enzymatic hydrolysis.

17. The method according to claim 16, wherein said mechanical pre-treatment comprises shredding or pulping.