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

• US 10,465,209 B2
• Filed: 02/25/2012
• Issued: 11/05/2019
• Est. Priority Date: 09/30/2005
• Status: Active Grant

• Current Assignee: Renescience A/S
• Original Assignee: Renescience A/S
• Inventors: Noerholm, Nanna Dreyer, Larsen, Jan, Iversen, Frank Krogh
• Primary Examiner(s): Fox, Allison M
• Assistant Examiner(s): Xu, Qing
• Application Number:
  US13/405,262
• Publication Number:
  US 20120171732A1
• Time in Patent Office: 2,810 Days
• 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 processing unsorted municipal solid waste (MSW) comprising organic matter and inorganic matter, said method comprising:

subjecting said unsorted MSW to non-pressurized thermal pre-treatment, followed by

hydrolyzing said unsorted MSW by enzymatic hydrolysis so as to liquefy fermentable parts of said unsorted MSW to produce liquefied fermentable parts of said unsorted MSW, in the presence of non-fermentable solids, said unsorted MSW having a dry matter content of 20-50% (w/w) during said hydrolysis, followed by

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

wherein the enzymatic hydrolysis is carried out in a vessel along with free fall mixing of said unsorted MSW,

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

wherein said unsorted municipal solid waste can comprise source-sorted MSW comprising organic and inorganic matter.

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

3. The method according to claim 1, wherein the liquefied fermentable parts are subjected to fermentation using an ethanologenic microorganism.

4. The method according to claim 1, wherein the liquefied fermentable parts are subjected to fermentation involving addition of nitrogen sources.

5. The method according to claim 1, wherein the liquefied fermentable parts are subjected to fermentation involving addition of nutrients or vitamins.

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

7. The method according to claim 1, wherein the treatment time of the non-pressurised thermal pre-treatment is between 5-100 min. with a temperature ranging between 80-100°

C. and a steam admission of 0.01-1.5 kg/kg dry matter.

8. The method according to claim 1, wherein the enzymatic hydrolysis is performed with hydrolytic enzymes, supplied in either native form or in the form of microbial organisms giving rise to the accumulation of such enzymes.

9. The method according to claim 1, wherein said enzymatic hydrolysis lasts for 5-96 hours and with a temperature ranging from 20-105°

C.

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

11. The method according to claim 1, wherein the enzymatic hydrolysis is conducted using a mixture of enzymes including proteolytic enzymes.

12. The method according to claim 1, wherein the enzymatic hydrolysis is conducted using a mixture of enzymes including alpha amylases and glyco amylases.

13. The method according to claim 1, wherein the enzymatic hydrolysis is conducted using a mixture of enzymes including lipases.

14. The method according to claim 1, wherein the enzymatic hydrolysis is conducted using a mixture of enzymes including oxidative enzymes.

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

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

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

18. The method of claim 1, wherein the dry matter content of said unsorted MSW is 20-45% w/w during said hydrolysis.

19. A method of processing unsorted municipal solid waste (MSW) comprising:

subjecting said unsorted MSW to non-pressurized thermal pre-treatment, followed by

adding hydrolysis enzymes to said pretreated unsorted MSW and hydrolyzing said pretreated unsorted MSW by enzymatic hydrolysis so as to liquefy fermentable parts of the pretreated unsorted MSW to produce liquefied fermentable parts of the pretreated unsorted MSW, in the presence of non-fermentable solids, said pretreated unsorted MSW having a dry matter content of 20-80% (w/w) during said hydrolysis, followed by

separating the liquefied fermentable parts of said pretreated unsorted MSW from the non-fermentable solids,

wherein said hydrolysis enzymes comprise at least one enzyme selected from the group consisting of cellulases, hemicellulases, proteolytic enzymes, alpha amylases, glycoamylases, lipases, and oxidative enzymes,

wherein the enzymatic hydrolysis is carried out in a vessel along with free fall mixing of said pretreated unsorted MSW, and

wherein said unsorted municipal solid waste can comprise source-sorted MSW comprising organic and inorganic matter.

20. The method of claim 19, further comprising fermenting said separated liquefied fermentable parts of said pretreated unsorted MSW.