Process for manufacturing ethanol and for recovering glycerol, succinic acid, lactic acid, betaine, potassium sulfate, and free flowing distiller's dry grain and solubles or a solid fertilizer therefrom

• US 5,177,009 A
• Filed: 07/18/1989
• Issued: 01/05/1993
• Est. Priority Date: 12/22/1987
• Status: Expired due to Fees

• Current Assignee: Willem H. Kampen
• Original Assignee: Willem H. Kampen
• Inventors: Kampen, Willem H.
• Primary Examiner(s): Warden, Robert J.
• Assistant Examiner(s): McMahon, Timothy M.
• Application Number:
  US07/381,179
• Time in Patent Office: 1,267 Days
• Field of Search: 435/139, 435/141, 435/145, 435/146, 435/159, 435/161, 435/163
• US Class Current: 435/139
• CPC Class Codes: C12F 3/10 from distillery slops
• CPC Class Codes: C12P 7/06 Ethanol, i.e. non-beverage
• CPC Class Codes: C12P 7/20 Glycerol
• CPC Class Codes: C12P 7/46 Dicarboxylic acids having four or less carbon atoms, e.g. fumaric acid, maleic acid
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

This invention relates to the manufacture of ethanol and the recovery of such by-products therefrom as glycerol, betaine, succinic and lactic acid, potassium sulfate and a free flowing distiller'"'"'s dry grain and solubles useful as an animal feed or a component of food for humans or as a premix for agricultural fertilizer. The process disclosed is an improvement over that of U.S. application Ser. No. 136,415 in the area of enhancement of glycerol recovery from stillage resulting from the fermentation of a biomass mash, and involves production of glycerol in amount in excess of 10 grams per 100 grams of reducing sugar in the starting biomass mash.

Claims

1. A process for manufacturing ethanol and recovering glycerol as a by-product thereof comprising the steps of:

preparing a biomass mash,

fermenting the biomass mash with yeast to produce a fermented mash having at least about 9 grams of glycerol and 40 grams of ethanol per 100 grams of reducing sugar in the biomass mash,

distilling the fermented mash for producing ethanol and stillage,

clarifying the stillage produced from the distillation of the fermented mash by subjecting the liquid portion thereof to a cross-flow microfiltration system having inorganic membranes with pore sizes of 0.1 to about 10 microns,

passing the clarified stillage through an ion exclusion material for separating glycerol from other constituents of the clarified stillage, and

purifying the separated glycerol.

5. A process according to one of claims 1 or claim 2 or claim 3 or claim 4 wherein the step of fermenting a biomass mash comprises the step of mixing with the mash yeast cells in a concentration in excess of 100 grams per liter.

6. A process according to one of claims 1 or claim 2 or claim 3 or claim 4 wherein the step of preparing a biomass mash comprises the step of preparing a biomass mash having a dextrose equivalent of at least about 80 and the step of fermenting comprises mixing yeast cells with the mash.

7. A process according to one of claim 1 or claim 2 or claim 3 or claim 4 wherein the step of fermenting comprises the step of maintaining the pH of the mash substantially constant during the first two thirds of the fermentation process.

8. A process according to one of claim 1 or claim 2 or claim 3 or claim 4 wherein the step of fermenting the biomass mash comprises producing a fermented mash having at least about 15 grams of glycerol and 40 grams of ethanol per 100 grams of reducing sugar in the biomass mash.

9. A process according to one of claims 1 or claim 2 or claim 3 or claim 4 wherein the step of fermenting a biomass mash comprises the steps of preparing immobilized yeast cells, and mixing the immobilized yeast cells with the biomass mash.

10. A process according to one of claim 1 or claim 2 wherein the step of clarifying further comprises centrifugally separating solids from liquid constituents prior to microfiltration.

2. A process for manufacturing ethanol and recovering glycerol and betaine as by-products thereof comprising the steps of:

preparing a biomass mash from sugar beets,

fermenting the biomass mash with yeast to produce a fermented mash,

distilling the fermented mash for producing ethanol and stillage,

clarifying the stillage from the distillation of the fermented mash by subjecting the liquid portion thereof to a cross-flow microfiltration system having inorganic membranes with pore sizes of 0.1 to about 10 microns,

subjecting the clarified stillage to chromatographic separation by passing the stillage through an ion exclusion material for separating glycerol and betaine from other constituents of the clarified stillage and then from each other, and

purifying the separated glycerol and betaine.

3. A continuous process for manufacturing ethanol and recovering glycerol as by product thereof comprising the steps of:

preparing a biomass mash, and in a continuous process performing the steps of;

fermenting the biomass mash with yeast to produce a fermented mash having at least about 9 grams of glycerol and 40 grams of ethanol per 100 grams of reducing sugar in the biomass mash,

distilling the fermented mash for producing ethanol and stillage,

clarifying the stillage produced from the distillation of the fermented mash by subjecting the liquid portion thereof to a cross-flow microfiltration system having inorganic membranes with pore sizes of 0.1 to about 10 microns,

4. A continuous process for manufacturing ethanol and recovering glycerol as by-products thereof comprising the steps of:

preparing a biomass mash from sugar beets, and in a continuous process performing the steps of;

fermenting the biomass mash with yeast to produce a fermented mash,

distilling the fermented mash for producing ethanol and stillage,

clarifying the stillage produced from the distillation of the fermented mash by subjecting the liquid portion thereof to a cross-flow microfultration system having inorganic membranes with pore sizes of 0.1 to about 10 microns,

subjecting the clarified stillage to chromatographic separation for separating a glycerol product stream from other constituents of the clarified stillage, and

purifying the separated glycerol product stream.

11. A process for manufacturing ethanol and recovering at least two of glycerol, betaine, and succinic acid as by-products thereof comprising the steps of:

preparing a fermented mash from sugar beets,

distilling the fermented mash for producing ethanol and stillage,

clarifying the stillage produced from the distillation of the fermented mash by subjecting the liquid portion thereof to a cross-flow microfiltration system having inorganic membranes with pore sizes of 0.1 to about 10 microns,

passing the clarified stillage through an ion exclusion material for separating glycerol and succinic acid and betaine one from another and from other constituents of the clarified stillage,

purifying the separated glycerol, succinic acid, and betaine, and

drying any stillage residue.

12. A process for manufacturing ethanol and recovering glycerol and lactic acid as by-products thereof comprising the steps of:

preparing the biomass mash,

fermenting the biomass mash with yeast to produce a fermented mash having at least about 9 grams of glycerol and 40 grams of ethanol per 100 grams of reducing sugar in the biomass mash,

distilling the fermented mash for producing ethanol and stillage,

clarifying the stillage produced from the distillation of the fermented mash by subjecting the liquid portion thereof to a cross-flow microfiltration system having inorganic membranes with pore sizes of 0.1 to about 10 microns, and

passing the clarified stillage through an ion exclusion material for separating glycerol and lactic acid one from another and from other constituents of the clarified stillage.

13. A process for manufacturing ethanol and recovering glycerol and betaine as by-products thereof comprising the steps of:

preparing a biomass mash from sugar beets,

fermenting the biomass mash with yeast to produce a fermented mash,

distilling the fermented mash for producing ethanol and stillage,

clarifying the stillage produced from the distillation of the fermented mash by subjecting the liquid portion thereof to a cross-flow microfiltration system having inorganic membranes with pore sizes of 0.1 to about 10 microns,

subjecting the clarified stillage to chromatographic separation by passing the stillage through an ion exclusion material for separating glycerol and betaine from the other constituents of the clarified stillage and then from each other, and

purifying the separated glycerol and betaine.