Farm-scale production of fuel ethanol and wet grain from corn in a batch process
The batch production of fuel grade ethanol and distillers' wet grain (wet solids) in a farm-scale process (1240-15,580 L/batch) is described. The procedure employs yeast fermentation of amylase-treated corn mash and a two-stage distillation. Primary emphasis in this study was on the cooking, fermentation and centrifugation steps. Without recycling, fermentation of the mash yielded beers with 10.0-10.5% ethanol. Recycling of stillage supernatant at full, 75, or 50% strengths produced enriched mashes that after 48-hour fermentation yielded beers with 5-14% more ethanol. Recycling twice with full-strength stillage supernatant at pH 7.0 increased the ethanol yield in the final beer 16.5%; however, the time to complete the final fermentation was extended from 48 to 72 hours and salt buildup occurred. By recycling at pH 5.4, it was possible to avoid salt buildup and obtain beers with 10.3-10.5% ethanol. Recycling resulted in increased levels of glucose, starch, crude protein, and fat in the beer and a reduced moisture content while the wet solids showed an increased starch content. Centrifugation after cooking or fermentation instead of after distillation reduced the mash volume 17-20% and this lowered the ethanol yield in the subsequently produced beer. Fermentation of a volume-restored mash supernatant gave a beer with only 9.25% ethanol. Mash wet solids varied somewhat chemically from beer and stillage solids. An economic and energy balance analysis of various modes of plant operation are provided and plant design considerations are suggested. (Refs. 31).
- Research Organization:
- Dept of Microbiology and Alcohol Fuel Research Lab, South Dakota State Univ, Brookings, SD 57007
- OSTI ID:
- 6142721
- Journal Information:
- Biotechnol. Bioeng.; (United States), Vol. 24:7
- Country of Publication:
- United States
- Language:
- English
Similar Records
Fuel ethanol and high protein feed from corn and corn-whey mixtures in a farm-scale plant
Fuel ethanol and high protein feed from corn and corn-whey mixtures in a farm-scale plant
Related Subjects
ETHANOL
BIOSYNTHESIS
MAIZE
FERMENTATION
AMYLASE
BY-PRODUCTS
CENTRIFUGATION
ECONOMICS
ENERGY BALANCE
ENZYMATIC HYDROLYSIS
ETHANOL FUELS
FARMS
PERFORMANCE TESTING
PRODUCTION
YIELDS
ALCOHOL FUELS
ALCOHOLS
BIOCONVERSION
CEREALS
CHEMICAL REACTIONS
DECOMPOSITION
ENZYMES
FUELS
GLYCOSYL HYDROLASES
GRAMINEAE
GRASS
HYDROLASES
HYDROLYSIS
HYDROXY COMPOUNDS
LYSIS
O-GLYCOSYL HYDROLASES
ORGANIC COMPOUNDS
PLANTS
SEPARATION PROCESSES
SOLVOLYSIS
SYNTHESIS
SYNTHETIC FUELS
TESTING
140504* - Solar Energy Conversion- Biomass Production & Conversion- (-1989)
090222 - Alcohol Fuels- Preparation from Wastes or Biomass- (1976-1989)