Ethanol
production was enhanced in the recycling batch compared with thefirst batch (freshwater was used).
Anaerobic digestion of the thin stillage also showed high efficiency and stability with a chemical oxygen
demand (COD) removal rate above 97% and a methane yield of 300 mL/g COD removed at both the lab
and pilot scale. In addition, the COD and conductivity of the thin stillage remained consistent after the
6th and 3rd batch, respectively