SYSTEM AND PROCESS FOR SEPARATING PURE CHEMICALS FROM BIOMASS EXTRACT

摘要

A system or plant and method for the production of pure alcohol, acetic acid or its derivatives from the extract containing hemicelluloses filtered after extraction of woody biomass or directly extracted from woody biomass. The process can be integrated with the host plant process to minimize the effect of loss of heat value from the extracted hemicelluloses and reduce the loading to the effluent plant.

主权项

1. A process for producing an alcohol and an acetate from a biomass-derived extract, said process comprising:
(a) providing a liquid extract produced during cooking of biomass, wherein said liquid extract comprises hemicelluloses and lignin; (b) if said liquid extract contains a first solids concentration of about 5 wt % or less, concentrating said liquid extract in a first evaporation stage, to produce a concentrated extract, wherein a first amount of acetic acid is evaporated and recovered from said first evaporation stage; (c) hydrolyzing said liquid extract from step (a) or said concentrated extract from step (b) in the presence of a mineral acid or enzymes, to produce a hydrolyzate comprising monomer sugars and released acetyl groups; (d) introducing said hydrolyzate to a second evaporation stage, operated at a pH less than 4.8, wherein a second amount of acetic acid is evaporated and recovered from said second evaporation stage; (e) combining said first and second amounts of acetic acid with an alkali, at a pH selected from 5 to 10, to convert acetic acid to an acetate salt; (f) filtering out said acetate salt with a membrane; and (g) fermenting said monomer sugars to an alcohol.