Alpena Biorefinery uses the wood sugar rich wash water from DPI’s manufacturing process as the feedstock for the biorefinery. The wood sugars are concentrated, hydrolyzed using acid, neutralized using lime, fermented, distilled and purified. The resulting ethanol is denatured with gasoline and stored prior to loadout for off-site sale. With addition of gasoline denaturant, the biorefinery produce up to 945,000 gallons of standard denatured ethanol. The biorefinery also produce approximately 700,000 gpy of an aqueous potassium acetate (50 wt%) coproduct. In addition, the biorefinery has significantly reduced the effluent volume and BOD load to the lagoon.
The project objectives of the biorefinery promote the national goals of energy independence, greenhouse gas reduction, and green job creation and retention.
The Alpena Biorefinery project utilizes a number of different unit operations to produce ethanol and potassium acetate. The basic components of the process are:
- Feedstock Pretreatment/Hydrolysis
- Membrane Separation
- Spent Material Handling
- Wastewater Handling
Awards: The plant has been awarded grants from the Michigan Economic Development Commission, and from the Department of Energy. The plant is expected to be fully operational in the third quarter of 2013.
The Alpena Biorefinery will be commercially replicated as Green Power+®