Method and system for producing ethanol

• US 8,323,923 B1
• Filed: 10/11/2007
• Issued: 12/04/2012
• Est. Priority Date: 10/13/2006
• Status: Active Grant

• Current Assignee: Apalta Tehnoloogia Ou
• Original Assignee: SweetWater Energy, Inc
• Inventors: Horton, Jerry W.
• Primary Examiner(s): Weber, Jon P
• Assistant Examiner(s): Srivastava, Kailash C
• Application Number:
  US11/974,129
• Time in Patent Office: 1,881 Days
• Field of Search: 435/41, 435/161
• US Class Current: 435/41
• CPC Class Codes: C12P 7/06 Ethanol, i.e. non-beverage
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

A method for producing ethanol is disclosed that uses a distributed production method where processing and pretreatment of combined liquid and solid material takes place outside of a centralized ethanol producing plant at a distributed feedstock processing plant, and separation of the resulting liquid and solid occurs prior to fermentation using this distributed production method. The resulting process liquid is then transported from each distributed feedstock processing plant to a centralized ethanol producing plant for fermentation, distillation and related processing. This novel distributed process reduces transportation costs, operating costs of ethanol producing plants, increases ethanol production throughput and improves the overall economics of ethanol production.

Claims

1. A distributed production method for producing sugar water and ethanol, the method comprising the steps of:

a) providing a feedstock comprising cellulose, hemicellulose, and/or lignocellulose to each of a plurality of portable feedstock processing plants each of which is located at or near a feedstock providing site;

b) processing the cellulose, hemicellulose, and/or lignocellulose of the feedstock at the plurality of portable feedstock processing plants to produce a sugar water and one or more byproducts, wherein processing comprises mechanical destruction or grinding, pretreatment, and enzymatic hydrolysis;

c) separating the sugar water produced from the cellulose, hemicellulose, and/or lignocellulose from the one or more byproducts at the plurality of portable feedstock processing plants;

d) concentrating the separated sugar water at the plurality of portable feedstock processing plants;

e) transporting the concentrated sugar water from the plurality of portable feedstock processing plants to a centralized ethanol producing plant; and

f) producing ethanol from the transported sugar water at the centralized ethanol producing plant.

5. The method of claim 1, wherein the producing step comprises producing ethanol from the transported sugar water at the centralized ethanol producing plant by fermenting the sugar water.

6. The method of claim 1, wherein the feedstock comprising cellulose, hemicellulose, and/or lignocellulose is corn stover, cereal straws, sugarcane bagasse, sawdust and paper pulp, waste materials, switchgrass, animal feed, animal manure, paper, cardboard, or a combination thereof.

7. The method of claim 1, wherein the one or more byproducts are used as animal feed, animal bedding, or compost.

8. The method of claim 1, wherein the pretreatment comprises dilute-acid thermochemical treatment.

9. The method of claim 1, further comprising providing the plurality of portable feedstock processing plants.

10. The method of claim 1, wherein the processing comprises hydrolysis of the cellulose, hemicellulose, and/or lignocellulose to one or more component sugars.

11. The method of claim 5, further comprising distilling the fermented sugar water to produce a distillate.

12. The method of claim 5, further comprising denaturing the ethanol.

13. The method of claim 5, further comprising selling the ethanol produced at the ethanol producing plant.

14. The method of claim 10, wherein the one or more component sugars comprise xylose.

15. The method of claim 10, wherein the one or more component sugars comprise glucose.

16. The method of claim 11, further comprising dehydrating the distillate.

2. A distributed production method for producing sugar water and ethanol, the method comprising the steps of:

a) providing a feedstock comprising cellulose, hemicellulose, and/or lignocellulose to each of a plurality of portable feedstock processing plants each of which is located at or near a feedstock providing site;

b) processing the cellulose, hemicellulose, and/or lignocellulose of the feedstock at the plurality of portable feedstock processing plants to produce a sugar water and one or more byproducts, wherein processing comprises mechanical destruction or grinding, pretreatment, and enzymatic hydrolysis;

c) separating the sugar water produced from the cellulose, hemicellulose, and/or lignocellulose from the one or more byproducts at the plurality of portable feedstock processing plants;

d) transporting the concentrated sugar water from the plurality of portable feedstock processing plants to a centralized ethanol producing plant; and

e) producing ethanol from the transported sugar water at the centralized ethanol producing plant.

17. The method of claim 2, wherein the producing step comprises producing ethanol from the transported sugar water at the centralized ethanol producing plant by fermenting the sugar water.

18. The method of claim 2, wherein the feedstock comprising cellulose, hemicellulose, and/or lignocellulose is corn stover, cereal straws, sugarcane bagasse, sawdust and paper pulp, waste materials, switchgrass, animal feed, animal manure, paper, cardboard, or a combination thereof.

19. The method of claim 2, wherein the one or more byproducts are used as animal feed, animal bedding, or compost.

20. The method of claim 2, wherein the pretreatment comprises dilute-acid thermochemical treatment.

21. The method of claim 2, wherein the processing comprises hydrolysis of the cellulose, hemicellulose, and/or lignocellulose to one or more component sugars.

22. The method of claim 17, further comprising distilling the fermented sugar water to produce a distillate.

23. The method of claim 17, further comprising denaturing the ethanol.

24. The method of claim 17, further comprising selling the ethanol produced at the ethanol producing plant.

25. The method of claim 21, wherein the one or more component sugars comprise xylose.

26. The method of claim 21, wherein the one or more component sugars comprise glucose.

27. The method of claim 22, further comprising dehydrating the distillate.

3. A distributed production method for producing sugar water and ethanol, the method comprising the steps of:

a) providing a feedstock comprising cellulose, hemicellulose, and/or lignocellulose to each of a plurality of portable feedstock processing plants each of which is located at or near a feedstock providing site;

b) processing the cellulose, hemicellulose, and/or lignocellulose of the feedstock at the plurality of portable feedstock processing plants to produce a sugar water comprising xylose, and one or more products and/or byproducts, wherein processing comprises mechanical destruction or grinding, dilute acid thermochemical treatment, and enzymatic hydrolysis;

c) separating the sugar water comprising xylose from the one or more products and/or byproducts at the plurality of portable feedstock processing plants;

d) concentrating the separated sugar water at the plurality of portable feedstock processing plants;

e) transporting the concentrated sugar water from the plurality of portable feedstock processing plants to a centralized ethanol producing plant; and

f) producing ethanol from the transported sugar water at the centralized ethanol producing plant.

4. A distributed production method for producing sugar water and ethanol, the method comprising the steps of:

a) providing a feedstock comprising cellulose, hemicellulose, and/or lignocellulose to each of a plurality of portable feedstock processing plants each of which is located at or near a feedstock providing site;

b) processing the cellulose, hemicellulose, and/or lignocellulose of the feedstock at the plurality of portable feedstock processing plants to produce a sugar water comprising glucose, and one or more products and/or byproducts, wherein processing comprises mechanical destruction or grinding, dilute acid thermochemical treatment, and enzymatic hydrolysis;

c) separating the sugar water comprising glucose from the one or more products and/or byproducts at the plurality of portable feedstock processing plants;

d) concentrating the separated sugar water at the plurality of portable feedstock processing plants;

e) transporting the concentrated sugar water from the plurality of portable feedstock processing plants to a centralized ethanol producing plant; and

f) producing ethanol from the transported sugar water at the centralized ethanol producing plant.