Agricultural residues
Agricultural residues such as corn stover, soybean stubble and straw represent a huge,
available and sustainable source of fuel. Their composition is about 70% cellulose and
hemicellulose and 15-20% lignin. Cellulose and hemicellulose can be converted to
ethanol and lignin burned as a boiler fuel for steam/electricity generation. Developing
ways to quickly collect, handle and store biomass economically is required for biomass to
ethanol commercialization, along with improved process technology.
The theoretical amount of ethanol per dry MKg of Ag residue is 500 liters (130
gallons/ton). Mature conversion technology yield is estimated to be near 80%, 415 liters,
108 gallons/ton (Lynd, 1996). For initial processes, an overall 60% yield is generally
used, resulting in 300 liters (80 gallons/ton). The energy content in the lignin can offset
the ethanol processing energy requirements. Corn stover collection
