Volatile organic compounds (VOCs) are released during the drying of distiller\u27s wet grains from dry-mill ethanol production plants. Almost nothing has been studied about these emissions so far including the information gaps on the types of VOCs emitted and the temperature range at which most of them are evolved. One of the two objectives of this study is to find out the temperature ranges where emission of VOCs is possible and also to investigate the main cause of VOC emissions. Samples from ethanol plant including distiller\u27s wet grains, distiller\u27s dried grains with solubles, syrup, and thin stillage were tested using thermogravimetric and derivative thermogravimetric analyses (DTGA) to acquire information on the loss of volatiles as a function of temperature. The results showed weight loss events in all the samples in the temperature range of 25-100ðC and are expected to be due to moisture and volatile organic compounds. Thin stillage obtained from centrifuging the whole stillage has a very high chemical oxygen demand (COD) of 75,000 mg/L. A portion of thin stillage is recycled to the plant for reuse and remaining is sent to the evaporator to be converted into syrup which is then added to the DWG during drying operations. The other objective of this study is the treatment of thin stillage, which would help in providing cleaner recycle water to the ethanol industry and in reducing the emissions of VOCs. Ozonation and catalytic ozonation were applied for the removal of COD from thin stillage as simple single-step unit processes. Two different catalysts Fe(II) and Fe(III) were used and both the catalysts resulted in almost the same improved COD removal rates when compared to ozonation alone
