F7 Ethanol Flashcards
What feedstock can ethanol be made of?
All sugar-based biomass can be fermented to ethanol, ex grapes, sugar beets, corn, wheat, pine, poplar etc.
What is the general reaction of fermentation?
Sugars → alkohol + CO2
Depending on feedstock, different pretreatment stages are required prior to fermentation, give some examples:
- chipping
- grinding
- steam explosion
- hydrolysis
What is the fermentation overview (schematic)?
What are the steps of producing sugar based ethanol?
What is the pretreatment and what by-products are there?
What are the steps of producing starch based ethanol?
What is the pretreatment and what by-products are there?
What are the steps of producing cellulose based ethanol?
What is the pretreatment and what by-products are there?
Where can cellulose be found?
- Wood
- agricultural residues, ex bagasse and corn stover
Wood composes of cellulose, hemicellulose and lignin - which of these can be fermented?
The cellulose and part of the hemicellulose are fermentable but lignin is not.
What is the purpose of pre-treatment of cellulose?
And what is most common to use?
What is the purpose of pre-hydrolysis of cellulose?
And what is most common to use?
The main hydrolysis step is where cellulose is converted into fermentable (simple) sugars, what are the three alternative routes?
The weak acid hydrolysis is a two stage process, what are they and what can be a possible problem?
What is Enzymatic hydrolysis? And name two possible pretreatments.
Schematic process of separate hydrolysis and fermentation (SHF) and simultaneous sacchrification and fermentation (SSF)
What organisms are used for fermenting sugars to alcohol?
What techniques are there for up-grading the ethanol?
What byproducts are there from ethanol production from wood/biomass?
Example of integration possibilities (beige one)
Example of integration possibilities (blue one)
