METHODS AND SYSTEMS FOR REMOVING UNDISSOLVED SOLIDS PRIOR TO EXTRACTIVE FERMENTATION IN THE PRODUCTION OF BUTANOL

• US 20120164302A1
• Filed: 06/17/2011
• Published: 06/28/2012
• Est. Priority Date: 06/18/2010
• Status: Active Grant

• Current Assignee: Gevo Incorporated
• Original Assignee: Butamax(TM) Advanced Biofuels LLC (BP PLC)
• Inventors: Lowe, David J., Zaher, Joseph J., ROESCH, BRIAN MICHAEL, Burlew, Keith H., Hallam, John W.
• Granted Patent: US 8,557,540 B2
• Time in Patent Office: Days
• US Class Current: 426/601
• CPC Class Codes: A23K 10/38 from distillers' or brewers' waste
• CPC Class Codes: B01D 11/0492 Applications, solvents used
• CPC Class Codes: B01D 21/26 Separation of sediment aided by centrifugal force or centripetal forcecentrifuges B04B; cyclones B04C
• CPC Class Codes: B01D 21/262 by using a centrifuge
• CPC Class Codes: B01D 3/002 by continuous methods
• CPC Class Codes: C07C 29/86 by liquid-liquid treatment
• CPC Class Codes: C11B 1/025 by enzymes or microorganisms, living or dead
• CPC Class Codes: C11B 13/00 Recovery of fats, fatty oils or fatty acids from waste materials
• CPC Class Codes: C12F 3/10 from distillery slops
• CPC Class Codes: C12M 1/00 Apparatus for enzymology or microbiology
• CPC Class Codes: C12M 21/12 for producing fuels or solvents C12M21/04 takes precedence; liquid carbonaceous fuels C10L1/00, solid fuels C10L5/00
• CPC Class Codes: C12M 45/04 Phase separators; Separation of non fermentable material; Fractionation
• CPC Class Codes: C12M 45/09 by enzymatic treatment
• CPC Class Codes: C12N 1/14 Fungi culture of mushrooms A01G18/00; as new plants A01H15/00; Culture media therefor
• CPC Class Codes: C12N 15/00 Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor mutants or genetically engineered microorganisms, per se C12N1/00, C12N5/00, C12N7/00; new plants per se A01H; plant reproduction by tissue culture techniques A01H4/00; new animals per se A01K67/00; use of medicinal preparations containing genetic material which is inserted into cells of the living body to treat genetic diseases, gene therapy A61K48/00
• CPC Class Codes: C12P 7/16 Butanols
• CPC Class Codes: C12P 7/18 polyhydric
• CPC Class Codes: C12P 7/6418 by hydrolysis of fatty acid esters
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02W 30/74 Recovery of fats, fatty oils, fatty acids or other fatty substances, e.g. lanolin or waxes

Abstract

A method and system for efficiently producing a fermentative product alcohol such as butanol utilizing in situ product extraction are provided. The efficiency is obtained through separating undissolved solids after liquefying a given feedstock to create a feedstock and prior to fermentation, for example, through centrifugation. Removal of the undissolved solids avoids problems associated with having the undissolved solids present during in situ production extraction, and thereby increases the efficiency of the alcohol production.

Claims

1. A method comprising:

providing a biomass feedstock slurry comprising fermentable carbon source, undissolved solids, and water;

separating at least a portion of the undissolved solids from said slurry whereby (i) an aqueous solution comprising fermentable carbon source and (ii) a wet cake co-product comprising solids are generated; and

adding the aqueous solution to a fermentation broth comprising recombinant microorganisms in a fermentation vessel whereby a fermentative product is produced;

wherein the biomass processing productivity is improved.

2. The method of claim 1, wherein the improved biomass processing productivity comprises improved fermentative product and co-product recoverability relative to a fermentative product produced in the presence of undissolved solids.

3. The method of claim 1, wherein the improved biomass processing productivity includes one or more of increased process stream recyclability, increased fermentor volume efficiency, and increased biomass feedstock load feeding.

4. The method of claim 1, further comprising contacting the fermentation broth with an extractant wherein the extractant has increased extraction efficiency relative to a fermentation broth comprising undissolved solids.

5. The method of claim 4, wherein increased extraction efficiency includes one or more of stabilized partition coefficient of the extractant, enhanced phase separation of the extractant from the fermentation broth, enhanced liquid-liquid mass transfer coefficient, increased extractant recovery and recyclability, and preserved extractant for recovery and recycle.

6. The method of claim 4, wherein the extractant is an organic extractant.

7. The method of claim 6, wherein the extractant comprises one or more immiscible organic extractants selected from the group consisting of C₁₂ to C₂₂ fatty alcohols, C₁₂ to C₂₂ fatty acids, esters of C₁₂ to C₂₂ fatty acids, C₁₂ to C₂₂ fatty aldehydes, C₁₂ to C₂₂ fatty amides, and mixtures thereof.

8. The method of claim 7, wherein the extractant comprises C₁₂ to C₂₂ fatty acids derived from corn oil.

9. The method of claim 1, wherein the undissolved solids are separated from feedstock slurry by decanter bowl centrifugation, tricanter centrifugation, disk stack centrifugation, filtering centrifugation, decanter centrifugation, filtration, vacuum filtration, beltfilter, pressure filtration, filtration using a screen, screen separation, grating, porous grating, flotation, hydroclone, filter press, screwpress, gravity settler, vortex separator, or combination thereof.

10. The method of claim 1, further comprising the step of liquefying a feedstock to create a biomass feedstock slurry;

wherein the feedstock is selected from corn grain, corn cobs, crop residues such as corn husks, corn stover, grasses, corn, wheat, rye, wheat straw, barley, barley straw, hay, rice straw, switchgrass, waste paper, sugar cane bagasse, sorghum, sugar cane, soy, components obtained from milling of grains, cellulosic material, lignocellulosic material, trees, branches, roots, leaves, wood chips, sawdust, shrubs and bushes, vegetables, fruits, flowers, animal manure, and mixtures thereof.

11. The method of claim 10, wherein the feedstock is corn.

12. The method of claim 10, wherein the feedstock is fractionated or unfractionated.

13. The method of claim 10, wherein the feedstock is wet milled or dry milled.

14. The method of claim 10, further comprising the step of increasing the reaction temperature during liquefaction.

15. The method of claim 10, wherein the feedstock slurry comprises oil from the feedstock and said oil is separated from the slurry.

16. The method of claim 15, wherein the wet cake comprises feedstock oil.

17. The method of claim 1, wherein the wet cake is washed with water to recover oligosaccharides present in the wet cake.

18. The method of claim 17, wherein the recovered oligosaccharides are added to the fermentation vessel.

19. The method of claim 1, wherein the wet cake is further processed to provide an improved co-product.

20. The method of claim 19, wherein the co-product is further processed to form an animal feed product.

21. The method of claim 1, wherein the wet cake is washed with solvent to recover oil present in the wet cake.

22. The method of claim 21, wherein the solvent is selected from hexane, butanol, isobutanol, isohexane, ethanol, and petroleum distillates.

23. The method of claim 1, wherein the fermentative product is a product alcohol selected from the group consisting of methanol, ethanol, propanol, butanol, pentanol, and isomers thereof.

24. The method of claim 1, wherein the recombinant microorganism comprises an engineered butanol biosynthetic pathway.

25. The method of claim 1, further comprising:

at least partially vaporizing the fermentation broth and product and optionally CO₂ wherein a vapor stream is produced and recover the product from the vapor stream.

26. The method of claim 25, further comprising contacting the vapor stream with an absorption liquid phase wherein at least a portion of the vapor stream is absorbed into the absorption liquid phase;

wherein the temperature of the onset of the absorption of the vapor stream into the absorption liquid phase is greater than the temperature of the onset of condensation of the vapor stream in the absence of the absorption liquid phase.

27. The method of claim 25, wherein the vaporizing and contacting steps are carried out under vacuum conditions.

28. The method of claim 25, wherein the separating a substantial portion of the undissolved solids from said slurry provides for a higher vapor pressure of the fermentation broth relative to a fermentation broth comprising undissolved solids.

29. The method of claim 28, wherein the higher vapor pressure provides for more efficient vaporization product recovery.

30. The method of claim 29, wherein the more efficient vaporization product recovery includes one or more of lower capital investment, smaller vaporization, absorption, compression, and refrigeration equipment, improved mass transfer rates, less energy for vaporization, and lower absorbent flow rate.

31. A method for producing butanol comprising:

providing a feedstock;

liquefying the feedstock to create a feedstock slurry, wherein the feedstock slurry comprises oligosaccharides, oil, and undissolved solids;

separating undissolved solids from the feedstock slurry to create (i) an aqueous solution comprising oligosaccharides, (ii) a wet cake comprising undissolved solids, and (iii) an oil phase;

contacting the aqueous solution with a fermentation broth in a fermentor;

fermenting the oligosaccharides in the fermentor to produce butanol; and

performing in situ removal of the butanol from the fermentation broth as the butanol is produced,

wherein removal of the undissolved solids from the feedstock slurry increases the efficiency of the butanol production.

32. The method of claim 31, wherein the feedstock is corn and the oil is corn oil.

33. The method of claim 32, wherein the undissolved solids comprise germ, fiber, and gluten.

34. The method of claim 33, further comprising dry milling the feedstock.

35. The method of claim 32, wherein the corn is unfractionated.

36. The method of claim 31, wherein the undissolved solids are separated by decanter bowl centrifugation, tricanter centrifugation, disk stack centrifugation, filtering centrifugation, decanter centrifugation, filtration, vacuum filtration, beltfilter, pressure filtration, filtration using a screen, screen separation, grating, porous grating, flotation, hydroclone, filter press, screwpress, gravity settler, vortex separator, or combination thereof.

37. The method of claim 31, wherein the step of separating undissolved solids from the feedstock slurry comprises centrifuging the feedstock slurry.

38. The method of claim 37, wherein centrifuging the feedstock slurry separates the feedstock into a first liquid phase comprising the aqueous solution, a solid phase comprising the wet cake, and a second liquid phase comprising the oil.

39. The method of claim 38, wherein the wet cake is washed with water to recover oligosaccharides present in the wet cake.

40. The method of claim 31, wherein the in situ removal comprises liquid-liquid extraction.

41. The method of claim 40, wherein an extractant for the liquid-liquid extraction is an organic extractant.

42. The method of claim 31, wherein saccharification of the oligosaccharides in the aqueous solution occurs simultaneously with fermenting the oligosaccharides in the fermentor.

43. The method of claim 31, further comprising the step of increasing the reaction temperature during liquefaction.

44. The method of claim 31, further comprising saccharifying the oligosaccharides prior to fermenting the oligosaccharides in the fermentor.

45. The method of claim 44, wherein the step of removing undissolved solids from the feedstock slurry comprises centrifuging the feedstock slurry.

46. The method of claim 45, wherein centrifuging the feedstock slurry occurs prior to saccharifying the sugar.

47. The method of claim 31, wherein the fermentation broth comprises a recombinant microorganism comprising a butanol biosynthetic pathway.

48. The method of claim 31, wherein the butanol is isobutanol.

49. The method of 31, wherein the step of removing undissolved solids from the feedstock slurry increases the efficiency of the butanol production by increasing a liquid-liquid mass transfer coefficient of the butanol from the fermentation broth to the extractant;

increases the efficiency of the butanol production by increasing an extraction efficiency of the butanol with an extractant;

increases the efficiency of the butanol production by increasing a rate of phase separation between the fermentation broth and an extractant;

increases the efficiency of the butanol production by increasing recovery and recycling of an extractant;

or increases the efficiency of the butanol production by decreasing a flow rate of an extractant.

50. A system for producing butanol comprising:

a liquefaction vessel configured to liquefy a feedstock to create a feedstock slurry, the liquefaction vessel comprising;

an inlet for receiving the feedstock; and

an outlet for discharging a feedstock slurry, wherein the feedstock slurry comprises sugar and undissolved solids;

a centrifuge configured to remove the undissolved solids from the feedstock slurry to create (i) an aqueous solution comprising the sugar and (ii) a wet cake comprising the portion of the undissolved solids, the centrifuge comprising;

an inlet for receiving the feedstock slurry;

a first outlet for discharging the aqueous solution; and

a second outlet for discharging the wet cake; and

a fermentor configured to ferment the aqueous solution to produce butanol, the fermentor comprising;

a first inlet for receiving the aqueous solution;

a second inlet for receiving an extractant;

a first outlet for discharging the extractant rich with butanol; and

a second outlet for discharging fermentation broth.

51. The system of claim 50, wherein the centrifuge further comprises a third outlet for discharging an oil created while removing the undissolved solids from the feedstock slurry.

52. The system of claim 50, further comprising a saccharification vessel configured to saccharify the sugar in the feedstock slurry, the saccharification vessel comprising:

an inlet for receiving the feedstock slurry; and

an outlet for discharging the feedstock slurry.

53. The system of claim 52, further comprising a saccharification vessel configured to saccharify the sugar in the aqueous solution, the saccharification vessel comprising:

an inlet for receiving the aqueous solution; and

an outlet for discharging the aqueous solution.

54. The system of claim 50, further comprising a dry mill configured to grind the feedstock, the dry mill comprising:

an inlet for receiving the feedstock; and

an outlet for discharging ground feedstock.

55. A composition comprising:

20-35 wt % crude protein,

1-20 wt % crude fat,

0-5 wt % triglycerides,

4-10 wt % fatty acids, and

2-6 wt % fatty acid isobutyl esters.

56. A composition comprising:

25-31 wt % crude protein,

6-10 wt % crude fat,

4-8 wt % triglycerides,

0-2 wt % fatty acids, and

1-3 wt % fatty acid isobutyl esters.

57. A composition comprising:

20-35 wt % crude protein,

1-20 wt % crude fat,

0-5 wt % triglycerides,

4-10 wt % fatty acids, and

2-6 wt % fatty acid isobutyl esters.

58. A composition comprising:

26-34 wt % crude protein,

15-25 wt % crude fat,

12-20 wt % triglycerides,

1-2 wt % fatty acids,

2-4 wt % fatty acid isobutyl esters,

1-2 wt % lysine,

11-23 wt % NDF, and

5-11 wt % ADF.