Sugar beets are the main source of sugar in northern countries. Usually, beets are washed, cut into pieces and boiled out. The liquid with the sugar is evaporated. Consequently, highly concentrated washing waters with CODs between 5 and 30 g/L COD and medium concentrated condensates occur for treatment. BHU has a wide know-how for the treatment of theses streams. Washing waters will be treated by anaerobic treatment, however calciumcarbonate will precipitate. Therefore, BHU has developped and improved the gas mixed reactor (GMR) providing safe wastewater treatment while producing biogas at the same time. Subsequent aerated biological treatment (BIO) will treat wastewater down to discharge limits.