System and method for conditioning a hardwood pulp liquid hydrolysate

• US 8,608,970 B2
• Filed: 07/21/2011
• Issued: 12/17/2013
• Est. Priority Date: 07/23/2010
• Status: Expired due to Fees

• Current Assignee: Red Shield Acquisition LLC (Ahlstrom Oyj), University of Maine System Board of Trustees
• Original Assignee: Red Shield Acquisition LLC (Ahlstrom Oyj), University of Maine System Board of Trustees
• Inventors: Waite, Darrell M., Arnold, Richard, St. Pierre, James, Pendse, Hemant P., Ceckler, William H.
• Primary Examiner(s): Mellon, David C
• Application Number:
  US13/187,818
• Publication Number:
  US 20120017891A1
• Time in Patent Office: 880 Days
• Field of Search: 210/639, 210/651, 210/652, 210/664, 210/663, 210/774, 210/806, 210/634, 210/642, 210/644, 210/649, 210/650, 210/665, 210/668, 210/688, 210/681, 210/689, 210/690, 210/702, 210/712, 210/723, 210/724, 210/765, 210/928, 210/912, 127/36, 127/37, 127/55, 127/46.1, 127/1, 127/34, 127/43, 127/44, 127/47, 127/48, 127/50, 127/53, 127/58, 127/61, 127/62, 204/627, 162 29- 46, 162/239, 435/262, 435/267, 435/271, 435/274, 435/275, 435/276, 435/277
• US Class Current: 210/806
• CPC Class Codes: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: C13K 13/00 Sugars not otherwise provided for in this class
• CPC Class Codes: D21C 11/0007 Recovery of by-products, i.e. compounds other than those necessary for pulping, for multiple uses or not otherwise provided for volatile compounds obtained by decomposition of spent liquors in order to regenerate them D21C11/125; compounds obtained by fractionating the liquors in order to regenerate them D21C11/0042
• CPC Class Codes: D21C 11/0042 Fractionating or concentration of spent liquors by special methods concentration by evaporation D21C11/10
• CPC Class Codes: D21C 11/10 Concentrating spent liquor by evaporation evaporators B01D

Abstract

A system and method for hardwood pulp liquid hydrolysate conditioning includes a first evaporator receives a hardwood mix extract and outputting a quantity of vapor and extract. A hydrolysis unit receives the extract, hydrolyzes and outputs to a lignin separation device, which separates and recovers a quantity of lignin. A neutralization device receives extract from the lignin separation device and a neutralizing agent, producing a mixture of solid precipitate and a fifth extract. The solid precipitate is removed from the fifth extract. A second evaporator removes a quantity of acid from the fifth extract in a vapor form. This vapor may be recycled to improve total acid recovery or discarded. A desalination device receives the diluted extract, separates out some of the acid and salt and outputs a desalinated solution.

Claims

1. A hardwood pulp liquid hydrolysate conditioning method comprising the steps of:

receiving a first extract derived from a quantity of hardwood mix into a first evaporator and outputting a first quantity of vapor and a second extract;

hydrolyzing the second extract and outputting a third extract;

separating and recovering a quantity of lignin from the third extract and outputting a fourth extract;

adjusting a pH of the fourth extract, thereby forming a quantity of solid precipitate and fifth extract;

separating the quantity of solid precipitate from the fifth extract;

removing a first quantity of acid from the fifth extract within a second evaporator, outputting a second quantity of vapor having the first quantity of acid and outputting a sixth extract; and

removing a liquid having a quantity of salt, heavy metals, residual acid, and lignin from the sixth extract and outputting a seventh extract comprising a desalinated solution containing sugar.

2. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein receiving the first extract further comprises maintaining the first evaporator approximately above a pH of 6.

3. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein hydrolyzing further comprises hydrolyzing the second extract for substantially sixty minutes.

4. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein hydrolyzing further comprises hydrolyzing the second extract between an approximate pH of 0 and 2.

5. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein hydrolyzing further comprises hydrolyzing the second extract between an approximate temperature of 100°

C. and 120°

C.

6. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein adjusting the fourth extract further comprises adjusting the fourth extract to produce a fifth extract having a pH between 2 and 5.

7. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein the first quantity of acid removed further comprises a first quantity of acetic acid and a first quantity of formic acid.

8. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein separating and recovering a quantity of lignin further comprises the step of reducing a temperature of the third extract by chilling to below 20°

C.

9. The hardwood pulp liquid hydrolysate conditioning method of claim 1, wherein the quantity of residual acid further comprises a quantity of inorganic and organic acids.

10. The hardwood pulp liquid hydrolysate conditioning method of claim 1, further comprising:

removing a second quantity of acid from the sixth extract in a third evaporator stage while adding a quantity of water to the sixth extract; and

outputting the second quantity of acid to the first evaporator.

11. The hardwood pulp liquid hydrolysate conditioning method of claim 10, wherein at least two of the first evaporator, the second evaporation, and the third evaporation stage are combined as a single unit.

12. The hardwood pulp liquid hydrolysate conditioning method of claim 10, further comprising recovering the second quantity of acid from the third evaporator stage.

13. The hardwood pulp liquid hydrolysate conditioning method of claim 10, wherein the third evaporator stage is operated in dilution mode.

14. The hardwood pulp liquid hydrolysate conditioning method of claim 1, further comprising removing a liquid having a quantity of salt, heavy metals, residual acid, and lignin from the sixth extract by electro-dialysis.

15. The hardwood pulp liquid hydrolysate conditioning method of claim 1, further comprising recovering the first quantity of acid from the second quantity of vapor.

16. A hardwood pulp liquid hydrolysate conditioning method comprising the steps of:

receiving a first extract derived from a quantity of hardwood mix into a first evaporator stage and outputting a first quantity of vapor and a second extract;

hydrolyzing the second extract and outputting a third extract;

separating and recovering a quantity of lignin from the third extract and outputting a fourth extract;

adjusting a pH of the fourth extract, thereby forming a quantity of solid precipitate and fifth extract;

separating the quantity of solid precipitate from the fifth extract;

removing a first quantity of acid from the fifth extract within a second evaporator stage, outputting a second quantity of vapor having the first quantity of acid and outputting a sixth extract;

removing a second quantity of acid from the sixth extract in a third evaporator stage while inputting a quantity of water and outputting the second quantity of acid to the first evaporator stage; and

removing a liquid having a quantity of salt, heavy metals, residual acid, and lignin from the sixth extract and outputting a seventh extract comprising a desalinated solution containing sugar.

17. The hardwood pulp liquid hydrolysate conditioning method of claim 16, wherein the quantity of water input into the third evaporator stage is concurrent with a vaporization of the sixth extract within the third evaporator stage.

18. A hardwood pulp liquid hydrolysate conditioning method comprising the steps of:

receiving a first extract derived from a quantity of hardwood mix into a first evaporator and outputting a first quantity of vapor and a second extract;

hydrolyzing the second extract and outputting a third extract;

separating and recovering a quantity of lignin from the third extract and outputting a fourth extract;

adjusting a pH of the fourth extract, thereby forming a quantity of solid precipitate and fifth extract;

separating the quantity of solid precipitate from the fifth extract;

removing a first quantity of acid from the fifth extract within a second evaporator, outputting a second quantity of vapor having the first quantity of acid and outputting a sixth extract; and

electrodialysing the sixth extract to remove a quantity of liquid having a quantity of salt, heavy metal, residual acid, and lignin and outputting a seventh liquid extract comprising a desalinated solution containing sugar.

19. The hardwood pulp liquid hydrolysate conditioning method of claim 18, further comprising removing a second quantity of acid from the sixth extract in a third evaporator stage while inputting a quantity of water and outputting the second quantity of acid to the first evaporator before electrodialysing the sixth extract.