| 摘要 |
Disclosed is a method for conversion of cellulosic material to ethanol and other products, the cellulosic material comprising at least cellulose, lignin, hemicellulose and ash, in which method the cellulosic material is cleaned and subjected to continuous hydrothermal pre-treatment without addition of acids or bases or other chemicals, which must be recovered, and in which method a liquid and a fibre fraction are produced, the fibre fraction being subjected to enzymatic liquefaction and saccharification, the method including ethanol fermentation and product recovery, the method comprising: - performing the hydrothermal pre-treatment by subjecting the cellulosic material to at least one soaking operation, and conveying the cellulosic material through at least one pressurised reactor defining a reactor pressure zone at an elevated pressure; the cellulosic material being heated to a temperature between 170 and 230 degrees C, and subjecting the cellulosic material to at least one pressing operation, creating a fibre fraction and a liquid fraction; - selecting the temperature and residence time for the hydrothermal pretreatment, so that the fibrous structure of the feedstock is maintained and at least 80% of the lignin is maintained in the fibre fraction; - unloading the pressed fibre fraction from the reactor pressure zone to a downstream closed zone, which is at a lower pressure than the reactor pressure zone, while collecting the released steam without access for air; and - unloading the liquid fraction from the pressurised reactor to a second closed zone, which is at a lower pressure than the reactor pressure zone, while collecting released steam without access for air. |
