US 12,312,626 B2
Method of ethanol fermentation with cellulose at high-solids loading
Hongdan Zhang, Guangdong (CN); and Xinwen Zhang, Guangdong (CN)
Assigned to SOUTH CHINA AGRICULTURAL UNIVERSITY, Guangdong (CN)
Filed by SOUTH CHINA AGRICULTURAL UNIVERSITY, Guangdong (CN)
Filed on Dec. 5, 2023, as Appl. No. 18/528,794.
Claims priority of application No. 202211547231.5 (CN), filed on Dec. 5, 2022.
Prior Publication US 2024/0182929 A1, Jun. 6, 2024
Int. Cl. C12P 7/10 (2006.01)
CPC C12P 7/10 (2013.01) 6 Claims
 
1. An ethanol fermentation method with cellulose at high-solids loading, comprising the following steps:
1) pretreatment: mixing a lignocellulose A pretreated with a sodium hydroxide-enhanced ethanol solution and a lignocellulose B pretreated with an aluminum chloride-enhanced ethanol solution in a ratio of (2:8) to (4:6) to obtain a mixed cellulose having a moisture content of 50%, and mixing the mixed cellulose and water according to a mass ratio of absolute dry cellulose to water of (7-10):100 to obtain a mixed cellulose solution;
2) sterilization treatment: adding nutrient salts to the mixed cellulose solution in step 1) for sterilization to obtain a sterilized solution;
3) saccharification and fermentation: adding cellulase and a yeast activation solution to the sterilized solution, and then performing simultaneous saccharification and fermentation, wherein a total time of simultaneous saccharification and fermentation is 24 to 200 hours;
4) material supplementation treatment: within 6 to 24 hours after start of fermentation, supplementing a sterilized mixed cellulose to a fermentation tank in batches, wherein when the supplementing is completed, a mass ratio of absolute dry cellulose to water is (30-45):100, and a final mixing ratio of the lignocellulose A to the lignocellulose B is (5:5) to (6.5:3.5);
and wherein the supplementing comprises a first material supplementation, a second material supplementation and a third material supplementation; 6 to 7 hours after the start of fermentation, the first material supplementation is performed to allow a ratio of the lignocellulose A to the lignocellulose B to be (4:6) to (6:4); 11 to 13 hours after the start of fermentation, the second material supplementation is performed; and 22 to 24 hours after the start of fermentation, and the third material supplementation is performed.