METHOD OF FREEING THE BOUND OIL PRESENT IN WHOLE STILLAGE AND THIN STILLAGE

• US 20070238891A1
• Filed: 03/20/2007
• Published: 10/11/2007
• Est. Priority Date: 02/16/2006
• Status: Active Grant

• Current Assignee: GS Cleantech Corporation (Greenshift Corporation)
• Original Assignee: GS Cleantech Corporation (Greenshift Corporation)
• Inventors: Winsness, David, Davis, John, Cantrell, David, Barlage, Gregory
• Granted Patent: US 7,608,729 B2
• Time in Patent Office: Days
• US Class Current: 554/8
• CPC Class Codes: A23K 10/38 from distillers' or brewers' waste
• CPC Class Codes: C11B 1/02 Pretreatment
• CPC Class Codes: C11B 1/04 of vegetable raw material C11B1/025 takes precedence
• CPC Class Codes: C11B 1/08 by hot pressing
• CPC Class Codes: C11B 1/10 by extracting
• CPC Class Codes: Y02P 60/87 Re-use of by-products of food processing for fodder production

Abstract

A method is provided for recovering oil from stillage including oil resulting from a process used for producing ethanol. In one embodiment, the method includes heating the stillage to a temperature sufficient to at least partially separate, or unbind, the oil therefrom The method further includes recovering the oil from the stillage.

Claims

1. A method of recovering oil from stillage, including oil, resulting from a process used for producing ethanol, comprising:

heating the stillage to a temperature sufficient to at least partially separate the oil therefrom; and

recovering the oil from the stillage.

2. The method of claim 1, wherein the heating step comprises heating the stillage to a temperature above 212°

F. at a pressure sufficient to prevent boiling.

3. The method of claim 2, wherein the heating step comprises heating the stillage to a temperature of about 230°

F. to less than about 250°

F.

4. The method of claim 2, wherein the heating step includes maintaining a pressure on the stillage of at least a vapor pressure necessary to unbind at least part of the oil without boiling the stillage.

5. The method of claim 2, Her including the step of allowing the stillage to return to a lower pressure after the heating step but before the recovering step.

6. The method of claim 1, wherein the recovering step comprises separating the oil from the stillage using gravity separation.

7. The method of claim 1, further including the step of cooling the stillage after the heating step and before the recovering step.

8. The method of claim 1, further including the step of concentrating the stillage prior to the heating step.

9. A system for recovering oil from pressurized stillage resulting from a process used for producing ethanol, comprising:

a first heater for receiving and superheating the pressurized stillage; and

a separator downstream of the first heater for recovering oil from the stillage.

10. The system of claim 9, further including a second heater for preheating the pressurized stillage before delivery to the first heater.

11. The system of claim 9, wherein the first heater comprises at least two heat exchangers.

12. The system of claim 9, wherein the separator comprises a gravity separator.

13. A method of recovering oil from concentrated stillage including oil resulting from a process used for producing ethanol, comprising:

pressure cooking the stillage to unbind the oil; and

recovering the unbound oil.

14. The method of claim 13, further including the step of concentrating the stillage prior to the pressure cooking step.

15. A method of recovering oil from stillage including oil resulting from a process used for producing ethanol, comprising:

hydrolyzing solids in the stillage; and

recovering the oil from the stillage,

whereby hydrolyzing the stillage makes the oil available for recovery and reduces viscosity.

16. The method of claim 15, wherein the step of hydrolyzing solids in the stillage includes heating the stillage to a temperature greater than 212°

F. at a pressure greater than atmospheric pressure.

17. The method of claim 15, wherein the method includes cooling the stillage before recovering the oil.

18. The method of claim 15, further including the step of concentrating the stillage.

19. A system for of recovering oil from pressurized whole stillage resulting from a process used for producing ethanol, comprising:

a first heater for receiving and superheating the pressurized whole stillage;

a decanter for obtaining thin stillage from the whole stillage;

an evaporator for concentrating the thin stillage; and

a separator downstream of the first heater for recovering oil from the thin stillage.

20. The system of claim 19, further including a second heater upstream of the evaporator for receiving and superheating the pressurized thin stillage.