Method and process for dry discharge in a pressurized pretreatment reactor

• US 8,628,623 B2
• Filed: 12/20/2010
• Issued: 01/14/2014
• Est. Priority Date: 12/21/2009
• Status: Expired due to Fees

• Current Assignee: Andritz Technology and Asset Management GmbH
• Original Assignee: Andritz Technology and Asset Management GmbH
• Inventors: Bolles, John, Rawls, Joseph Monroe, Stromberg, Bertil
• Primary Examiner(s): Reifsnyder, David A
• Application Number:
  US12/972,625
• Publication Number:
  US 20110180061A1
• Time in Patent Office: 1,121 Days
• Field of Search: 127/1, 127/37, 162/52, 162/60
• US Class Current: 127/37
• 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 3/02 with inorganic bases or alkaline reacting compounds, e.g. sulfate processes
• CPC Class Codes: D21C 3/04 with acids, acid salts or acid anhydrides D21C3/003 and D21C3/222 take precedence
• CPC Class Codes: D21C 7/00 Digesters

Abstract

A reactor for the treatment of lignocellulosic material and related methods. The reactor includes a vessel having an upper portion and a lower portion. A pressure envelope is formed between an outer wall of the vessel and at least one lower wall of the lower portion of the vessel, and the upper portion of the vessel and the pressure envelope are operatively connected with a pressurization line, such that a pressure of the pressure envelope and a pressure of the upper portion may be equalized.

Claims

1. A reactor for the treatment of biomass, the reactor comprising:

a vessel having an upper portion and a lower portion,

wherein the upper portion (i) is configured to receive biomass and is configured to pressurize and heat the biomass via a pressurizing gas and (ii) comprises at least one upper wall,

wherein the lower portion (i) is configured to receive the pressurized biomass and is configured to facilitate hydrolysis or autohydrolysis of the biomass without excess or free liquid, (ii) comprises at least one lower wall comprising a corrosion resistant material, and (iii) is configured to transport the biomass without a transport liquid,

the vessel further comprising a pressure envelope that is formed between an outer wall of the vessel and the at least one lower wall, the at least one lower wall being inside the vessel,

and wherein the upper portion of the vessel and the pressure envelope are operatively connected with a pressurization line, such that a pressure of the pressure envelope and a pressure of the upper portion may be equalized.

2. The reactor according to claim 1, wherein the lower portion is configured to transport the biomass without external agitation or rotation.

3. The reactor according to claim 1, wherein the corrosion resistant material comprises stainless steel, titanium, zirconium, a corrosion-resistant alloy, a ceramic coating, a polytetrafluoroethylene lining, or combinations thereof.

4. The reactor according to claim 1, wherein the upper portion is configured to pressurize the biomass up to a pressure of about 5 to 25 bar where the pressurizing gas is steam.

5. The reactor according to claim 1, wherein the upper portion is configured to pressurize the biomass to a pressure of about 60 bar where the pressurizing gas is ammonia.

6. The reactor according to claim 1, wherein the upper portion comprises carbon steel.

7. A method of hydrolyzing a biomass material, the method comprising the steps of:

feeding biomass material to a vessel having an upper portion a lower portion, and a pressure envelope formed between an outer wall of the vessel and at least one lower wall of the lower portion, the at least one lower wall of the lower portion being inside the vessel;

pressurizing the biomass in the upper portion using a pressurizing agent;

transferring the pressurized biomass to the lower portion in which hydrolysis or autohydryolsis reaction occurs without excess or free liquid; and

transferring the hydrolyzed biomass from the lower portion without introduction of a transport liquid; and

equalizing a pressure of the pressure envelope and a pressure of the upper portion via a pressurization line that connects the pressure envelope and the upper portion of the vessel.

8. The method of claim 7, wherein the step of feeding the biomass material is performed continuously.

9. The method of claim 7, wherein the step of feeding the biomass material is performed is a batch-wise process.

10. The method of claim 7, wherein the pressurizing agent comprises ammonia and wherein the step of pressurizing the biomass in the upper portion results in a pressure of up to about 60 bar.

11. The method of claim 7, wherein the pressurizing agent comprises steam and wherein the step of pressurizing the biomass in the upper portion results in a pressure of about 5 to 25 bar.

12. The method of claim 7, wherein the step of transferring the hydrolyzed biomass from the lower portion further occurs without external agitation or rotation.

13. The method of claim 7, wherein the hydrolysis reaction occurs with the addition of sulfuric, hydrochloric, hydrofluoric, phosphoric acid, or a combination thereof.

14. The method of claim 7, wherein the hydrolysis reaction occurs with the addition of acetic acid, formic acid, or a combination thereof.

15. The method of claim 7, wherein the hydrolysis reaction occurs with the addition of sulfuric acid.

16. The method of claim 7, wherein the biomass comprises wood, grass, or a combination thereof.

17. The method of claim 7 further comprising the step of feeding the biomass to the vessel via gravity.

18. The method of claim 7 further comprising the step of feeding the biomass to the vessel via a screw conveyor or a conveyor belt.

19. The method of claim 7 further comprising maintaining a condensate level in the pressure envelope so as to provide a heat source.