Liquefaction biomass processing with heat recovery

Patent metadata

Field	Value
Publication number	US-10144785-B2
Application number	US-201113754412-A
Country	US
Kind code	B2
Filing date	Jul 29, 2011
Priority date	Jul 30, 2010
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

Described are processes that include the non-enzymatic, hydrolytic liquefaction of lignocellulosic biomass to form digest slurries and heat recovery from such digest slurries. Due to enhanced flow properties of the digest slurries such heat recovery can be efficiently conducted in spiral, plate and frame or other heat exchanger designs, with the recovered heat going to unit operations of the process such as heating incoming pretreatment media for the liquefaction. Processes can also involve additional hydrolytic digestion of some or all of the initial slurry components with enzyme and/or additional heat recovery from the initial slurry by direct contact heat exchange in which a portion of the digest slurry liquids is flashed to vapor and that vapor is condensed onto incoming lignocellulosic biomass to the process. Processes as described can be integrated into ethanol manufacture by fermentation of sugars from the digested compositions.

First claim

The invention claimed is:

1. A method for processing lignocellulosic biomass, comprising:
providing a solid, particulate biomass, wherein said solid, particulate biomass is grass, sugar cane bagasse, sugar beet pulp, soybean stover, corn fiber, corn stover, oat straw, rice straw, rice hulls, barley straw, corn cobs, wheat straw, canola straw, oat hulls, wood, paper sludge, newsprint, or cardboard;
incubating a mixture comprising a first amount of said solid, particulate lignocellulosic biomass and a first amount of a liquid processing medium containing at least one dicarboxylic acid under heated conditions effective to form from the mixture a biomass digest composition exhibiting a yield stress that is less than half that of the mixture, said yield stress of the biomass digest composition being less than 15000 Pascals, and in which at least 10% by weight of the solid, particulate biomass has been converted to dissolved biomass components in the liquid medium including monomeric xylose and xylose oligomers, the digest composition also including undissolved lignocellulosic biomass particulates formed from the solid, particulate biomass, said undissolved lignocellulosic biomass particulates including lignin and cellulose;
pumping a lignocellulosic particulate digest slurry at least partially comprised of said dissolved biomass components including the monomeric xylose and xylose oligomers and at least partially comprised of said undissolved lignocellulosic biomass particulates through a first passage of a heat exchanger while passing a second amount of a liquid processing medium containing at least one dicarboxylic acid through a second passage of the heat exchanger so as to transfer heat from said lignocellulosic particulate digest slurry to said second amount of liquid processing medium to provide a preheated liquid processing medium; and
combining the preheated liquid processing medium with a second amount of said solid, particulate biomass.

2. The method of claim 1 , wherein the heat exchanger is a spiral heat exchanger.

3. The method of claim 1 , wherein the heat exchanger is a plate heat exchanger.

4. The method of claim 1 , wherein the biomass digest composition exhibits a yield stress in the range of 10000 Pascals to less than 15000 Pascals.

5. The method of claim 1 , wherein said pumping is at a flow rate of at least about 20 gallons per minute.

6. The method of claim 1 , wherein the digest composition comprises at least about 20 g/L of monomeric xylose.

7. The method of claim 1 , wherein the digest composition is constituted at least about 55% of undissolved solids.

8. The method of claim 1 , also comprising hydrolyzing the undissolved, lignocellulosic biomass particulates from the digest composition with cellulase to convert cellulose in the biomass particulate to glucose.

9. The method of claim 8 , wherein said hydrolyzing is conducted after said pumping.

10. The method of claim 1 , also comprising neutralizing said digest composition with a base.

11. The method of claim 1 , wherein said pumping comprises pumping with a centrifugal pump.

12. The method of claim 1 , wherein said pumping is sufficient to cause flow of the lignocellulosic particulate digest slurry through said first passage at a linear velocity of at least about 1 foot per second.

13. The method of claim 1 , wherein the first amount of the solid, particulate lignocellulosic biomass, on a dry weight basis, constitutes at least 15% by weight of the mixture.

14. The method of claim 1 , wherein the liquid processing medium of the mixture is at least 80% aqueous.

15. The method of claim 1 , also comprising, after said pumping and before said combining, flashing liquid from the lignocellulosic particulate digest slurry to vapors, and condensing the vapors upon and thereby heating the second amount of said solid, particulate lignocellulosic biomass.

16. The method of claim 1 , wherein the biomass digest composition is comprised at least 15% by weight total biomass solids on a dry weight basis, and wherein 10% to 45% of the total biomass solids are dissolved in the liquid medium.

17. The method of claim 1 , wherein the first passage has an inlet and an outlet, and wherein during said pumping the slurry experiences a pressure drop of no greater than about 20 psi.

18. The method of claim 1 , wherein said incubating comprises incubating the mixture in a vessel.

19. The method of claim 18 , wherein said incubating comprises heating the mixture with steam injected into the vessel.

20. The method of claim 18 , wherein for at least a portion of a duration of said incubating, the mixture is not subjected to mechanical mixing.

21. The method of claim 1 , wherein the lignocellulosic particulate digest slurry is comprised at least 10% by weight, on a dry weight basis, of particles having a maximum dimension greater than about 1 cm.

22. The method of claim 2 , wherein the spiral heat exchanger has a gap width of about 1 to 4 cm.

23. The method of claim 7 , wherein the lignocellulosic particulate digest slurry includes the digest composition.

24. The method of claim 23 , wherein the digest composition is undiluted in the lignocellulosic particulate digest slurry.

25. The method of claim 23 , wherein the digest composition is diluted in the lignocellulosic particulate digest slurry.

26. The method of claim 25 , wherein during said pumping, the digest slurry passes through the first passage at a linear velocity in the range of about 10 to about 50 feet per second.

27. A method for processing lignocellulosic biomass, comprising:
providing a solid, particulate biomass, wherein said solid, particulate biomass is grass, sugar cane bagasse, sugar beet pulp, soybean stover, corn fiber, corn stover, oat straw, rice straw, rice hulls, barley straw, corn cobs, wheat straw, canola straw, oat hulls, wood, paper sludge, newsprint, or cardboard;
subjecting said solid, particulate lignocellulosic biomass to acid-catalyzed liquefaction by incubating a mixture containing said solid, particulate biomass and at least one dicarboxylic acid under heated conditions effective to form from the mixture a biomass digest slurry exhibiting a yield stress that is less than half that of the mixture, said yield stress of the biomass digest slurry being less than 15000 Pascals, and in which at least 10% by weight of the solid, particulate biomass has been converted to dissolved biomass components in the liquid medium including monomeric xylose and xylose oligomers, the digest slurry also including undissolved, finely-divided lignocellulosic biomass particulates formed from the solid, particulate biomass, wherein the finely-divided lignocellulosic biomass particulates flow freely with the liquid medium; and
pumping a lignocellulosic particulate digest slurry including the dissolved biomass components including the monomeric xylose and the xylose oligomers and the undissolved, finely-divided lignocellulosic biomass particulates through a first passage of a heat exchanger while passing a liquid medium through a second passage of the heat exchanger so as to transfer heat from the lignocellulosic particulate digest slurry to the liquid medium.

28. The method of claim 27 , wherein the lignocellulosic biomass comprises wood.

29. The method of claim 27 , wherein the heat exchanger is a spiral heat exchanger.

30.

Assignees

• Ladisch Michael R
• Mosier Nathan
• Kim Youngmi
• Rooyen Justin Van
• Purdue Research Foundation

Inventors

• Ladisch Michael R
• Mosier Nathan
• Kim Youngmi
• Rooyen Justin Van

Classifications

• C08B1/00 Primary

  Preparatory treatment of cellulose for making derivatives thereof {, e.g. pre-treatment, pre-soaking, activation} · CPC title

• Y02E50/17

  Cross-Sectional Technologies · mapped topic

• Y02P20/124

  Cross-Sectional Technologies · mapped topic

• Y02E50/16

  Cross-Sectional Technologies · mapped topic

• C12N1/22 Primary

  Processes using, or culture media containing, cellulose or hydrolysates thereof · CPC title