Process for enzymatic hydrolysis of lignocellulosic material and fermentation of sugars
The invention relates to an integrated process for alcohol production from lignocellulosic material.
1. An integrated process for alcohol production from lignocellulosic material and enzyme production, wherein the process comprises:
enzymatic hydrolysis of the lignocellulosic material to obtain enzymatically hydrolysed lignocellulosic material,
solid/liquid separation of the enzymatically hydrolysed lignocellulosic material to obtain at least a solid fraction and at least a liquid fraction,
fermentation of a part of the solid fraction and/or a part of the liquid fraction by an alcohol producing microorganism to produce alcohol,
propagation of the alcohol producing microorganism by fermentation of a part of the liquid fraction and/or a part of the solid fraction,
propagation of an enzyme producing microorganism, and
production of enzymes by the enzyme producing microorganism.
2. The process according to claim 1 , wherein a part of the enzymatically hydrolysed lignocellulosic material and a part of the lignocellulosic material is used in the propagation of the enzyme producing microorganism and/or the production of enzymes by the enzyme producing microorganism.
3. The process according to claim 1 , wherein the enzymes produced by the enzyme producing microorganism are used in the enzymatic hydrolysis.
4. The process according to claim 1 , wherein the at least solid fraction comprises between 3 and 97 wt % C5 sugars.
5. The process according to claim 1 , wherein the at least liquid fraction comprises between 1 and 97 wt % C6 sugars.
6. The process according to claim 1 , wherein the enzymatic hydrolysis comprises at least:
a liquefaction wherein the lignocellulosic material is hydrolysed in at least a first container, and
a saccharification wherein the liquefied lignocellulosic material is hydrolysed in the at least first container and/or in at least a second container.
7. The process according to claim 1 , wherein the alcohol, the enzymes, the enzyme producing microorganism and/or the alcohol producing microorganism are recovered.
8. The process according to claim 1 , wherein the lignocellulosic material is subjected to at least one solid/liquid separation before the enzymatic hydrolysis.
9. The process according to claim 1 , wherein oxygen is added during the enzymatic hydrolysis.
10. The process according to claim 1 , wherein the enzyme producing microorganism is a fungus.
11. The process Process according to claim 10 , wherein the fungus is Rasamsonia.
12. The process according to claim 1 , wherein the enzymes are comprised in a whole fermentation broth.
13. The process according to claim 1 , wherein the alcohol producing microorganism is able to ferment at least a C5 sugar and at least a C6 sugar.
14. The process according to claim 13 , wherein the alcohol producing microorganism is a yeast.
15. The process according to claim 13 , wherein the alcohol producing microorganism is Saccharomyces cerevisiae.
16. The process according to claim 1 , wherein the dry matter content at the end of the enzymatic hydrolysis is 5 wt % or higher.
17. The process according to claim 1 , wherein the alcohol is ethanol.
18. The process according to claim 8 , wherein a part of the liquid fraction from the at least one solid/liquid separation of the lignocellulosic material before the enzymatic hydrolysis is combined with a part of the liquid fraction from the solid/liquid separation of the enzymatically hydrolysed lignocellulosic material, and the mixture is fermented by an alcohol producing microorganism to produce alcohol.