Bacteria Purify Ethanol Plant Wastewater

Farming for Energy: Araerobic Digesters -- bur boost for ethanol; manure to methane - does it pay; for digester farmer wannabes.:
by E.M. Morrison -- Ag Innovations News -- July 2001

Wastewater from the plant flows into a 30,000-gallon bioreactor, which looks like a tall, silver silo. Inside the reactor is a floating bed of hardworking bacteria. These "methanator bugs" break down chemical wastes in the water, removing more than 90 percent of the impurities that interfere with ethanol processing. The water is left clean enough to be reused in fermentation, Coler says.