Processes and apparatus for refining sugarcane to produce sugars, biofuels, and/or biochemicals

摘要

Conventionally, sugarcane processing avoids leaving residual sucrose in the bagasse, since the bagasse will be burned and the value of the sucrose would be lost. However, when coupled with a Green Power+® process to extract hemicelluloses, sucrose may also be extracted and recovered from the bagasse. In some variations, a process includes mechanically treating a feedstock to generate a sucrose-rich stream and lignocellulosic material that intentionally retains a significant amount of the initial sucrose in the feedstock; extracting the lignocellulosic material with steam and/or hot water to produce cellulose-rich solids and an extract liquor containing hemicellulosic oligomers and sucrose; and then hydrolyzing the hemicellulosic oligomers into a hemicellulose sugar stream. Each of the sucrose-rich stream and the hemicellulose sugar stream (containing the starting residual sucrose) may be recovered or further processed (e.g., fermented to ethanol). Similar processes are possible with energy cane, sugar beets, and energy beets.

主权项

1. A process for refining a sucrose-containing feedstock, said process comprising:
(a) providing a feedstock containing lignocellulosic material and sucrose; (b) mechanically treating said feedstock to generate a sucrose-rich stream and sucrose-depleted lignocellulosic material, wherein said sucrose-depleted lignocellulosic material retains at least 1% of the initial sucrose contained in said feedstock; (c) extracting said sucrose-depleted lignocellulosic material with steam and/or hot water to produce cellulose-rich solids and an extract liquor containing hemicellulosic oligomers and extracted sucrose; (d) hydrolyzing said hemicellulosic oligomers into a hemicellulose sugar stream, wherein said hemicellulose sugar stream comprises said extracted sucrose or a hydrolyzed form thereof; (e) recovering or further processing said hemicellulose sugar stream; (f) recovering or further processing said sucrose-rich stream; and (g) combusting said cellulose-rich solids to produce steam and/or electricity.