Method for cleaning a reactor for processing a lignocellulosic biomass

Patent metadata

Field	Value
Publication number	US-12378515-B2
Application number	US-201917416213-A
Country	US
Kind code	B2
Filing date	Dec 13, 2019
Priority date	Dec 21, 2018
Publication date	Aug 5, 2025
Grant date	Aug 5, 2025

Abstract

The present invention concerns a method for cleaning a reactor (4) for treating a lignocellulosic biomass (P), said method comprising the following steps:a) draining the reactor of the reaction mixture containing the biomass,b) filling the reactor with a basic aqueous solution (EB),c) draining the reactor,d) injecting steam (V) into the reactor,e) filling the reactor with an aqueous solution (E),f) draining the reactor.

First claim

The invention claimed is:

1. A method for cleaning a reactor ( 4 ) for treating a lignocellulosic biomass (P), said method comprising the following sequence of steps:
a) draining the reactor of the reaction mixture containing the biomass,
b) filling the reactor with a basic aqueous solution (EB),
c) draining the reactor,
d) injecting steam (V) into the reactor,
e) filling the reactor with an aqueous solution (E),
f) draining the reactor, and
wherein, during draining step c), the basic solution drained is recovered for recycling, with optional filtration to remove solid residues (C).

2. The method as claimed in claim 1 , wherein it comprises at least one step a′) of filling the reactor ( 4 ) with an aqueous solution (E), followed by a step a″) of draining the reactor, between step a) of draining the reaction mixture and step b) of filling with a basic aqueous solution (EB).

3. The method as claimed in claim 1 , wherein it further comprises, after step a), introducing particles of solid abrasive material into the reactor ( 4 ), either separately or by introducing the particles into the basic solution (EB) or into the or one of the aqueous solution(s) (E).

4. The method as claimed in claim 1 , wherein the basic aqueous solution (EB) and/or the or one of the aqueous solution(s) (E) is or are heated before introduction into the reactor ( 4 ), to a temperature of at least 20° C., and at most 90° C.

5. The method as claimed in claim 1 , wherein at least step b) of filling the reactor ( 4 ) with the basic aqueous solution (EB) takes place with the interior volume of the reactor at a temperature of at least 60° C.

6. The method as claimed in claim 1 , wherein, during draining step c), the basic solution drained is filtered for recovery of the solid residues (C) it contains, and in that these residues are treated for extraction of the basic solution from them for recycling thereof.

7. The method as claimed in claim 1 , wherein the immersion of the reactor ( 4 ) with the basic solution (EB), when the reactor has been filled as per step b), before it is drained, has a duration of between 30 seconds and 4 days.

8. The method as claimed in claim 1 , wherein the degree of filling of the reactor ( 4 ) with the biomass (EB) and/or with the or one of the aqueous solution(s) (E) is between 20 and 100%.

9. The method as claimed in claim 1 , wherein the steam (V) in step d) is injected at a pressure of between 1.10 5 and 20.10 5 Pa.

10. The method as claimed in claim 1 , wherein steps e) and f) are repeated at least twice.

11. A method for treating lignocellulosic biomass (P), comprising:
preparing an impregnation liquor containing a catalyst, in particular an acidic catalyst, —introducing the biomass into an impregnation reactor ( 3 ) for impregnation with the impregnation liquor,
transferring the impregnated biomass to a pretreatment reactor ( 4 ) for pretreatment therein by cooking,
enzymatically hydrolyzing the pretreated biomass,
alcoholically fermenting the enzymatic hydrolysis must obtained, wherein the method is carried out continuously over all or part of said steps, and in that it pauses at the stage of pretreatment in the pretreatment reactor for the pretreatment reactor to be cleaned with the method as claimed in claim 1 .

12. The method as claimed in claim 1 , wherein it pauses for the pretreatment reactor ( 4 ) to be cleaned according to a given frequency and/or on exceedance of a threshold value by a physicochemical or rheological characteristic of the reaction mixture in the reactor.

13. A plant for implementing the method as claimed in claim 1 , wherein it comprises a reactor ( 4 ) for pretreating lignocellulosic biomass, a tank ( 6 ) for preparing a basic aqueous solution (EB), which is in fluid connection with said reactor for bringing the basic solution (EB) from the tank into the reactor and for recycling all or part of the basic solution, withdrawn from the reactor when it is drained, from the reactor to said tank, with means, optionally, for filtering the solution withdrawn from the reactor before it is reintroduced into the preparation tank.

14. A plant for implementing the method as claimed in claim 11 , wherein it comprises in succession a reactor ( 3 ) for impregnating the biomass (P), fed with impregnating solution by a tank ( 1 ) for preparing said solution, a reactor ( 4 ) for pretreating the impregnated biomass, which is fed with basic aqueous solution (EB) by a tank ( 6 ) for preparing said solution, an enzymatic hydrolysis reactor, and an alcoholic fermentation reactor, with all of the reactors being mounted in series, or at least two of them.

Assignees

• Ifp Energies Now
• Institut National De Rech Pour Lagriculture Lalimentation Et Lenvironnement
• Agro Industrie Recherches Developpement

Inventors

• Bouras Meriem
• Aymard Caroline
• Carnnot Olivier

Classifications

• C12P2203/00

  Fermentation products obtained from optionally pretreated or hydrolyzed cellulosic or lignocellulosic material as the carbon source · CPC title

• C12P2201/00

  Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis · CPC title

• C12P19/14 Primary

  produced by the action of a carbohydrase {(EC 3.2.x)}, e.g. by alpha-amylase {, e.g. by cellulase, hemicellulase} · CPC title

• C12P7/10

  substrate containing cellulosic material · CPC title

• C12M23/58

  Reaction vessels connected in series or in parallel (combinations of bioreactors with other apparatus, C12M43/00) · CPC title