In the drying of thin stillage in a corn-to-ethanol process, suspended
solids are largely separated from the thin stillage by electrocoagulation
and polyacrylamide flocculation. Whole stillage contains solids that must
be dried. Prior to the dryer, the whole stillage is processed in a
centrifuge that generates wet cake. The wet cake goes directly to the
dryer. The thin stillage from the centrifuge is treated with
electrocoagulation and polyacrylamide polymer prior to being sent to a
rotary screen drum and settling tank. The settling tank supernate is then
sent to an evaporator. Condensate is taken off in the evaporator leaving
syrup that is sent to the distiller's dried grains with solubles (DDGS)
dryer along with the wet cake. The syrup is of significantly higher
solids content with the current invention than with Prior Art technology.
Energy savings in the DDGS dryer are achieved by the removal of water in
the evaporation prior to drying