The Grand Tokaj state-owned wine-growing estate, which is dedicated to preserving Hungary’s wine-growing tradition, will in future use oxygen for wastewater treatment. As the region’s largest wine-growing estate, Grand Tokaj supports 1000 local wine growers and buys up the grapes grown in Tokaj-Hegyalja, a region rich in tradition that has been designated a UNESCO World Heritage Site. This is the home of the “king of wines, wine of kings” – the sweet Tokaj wine. In spring and autumn, the wastewater from the winemaking process has a particularly high content of organic substances. The estate’s treatment facilities previously had an air feed and tended to reach their capacity limits during such phases. The option of building additional clarifiers was not considered for lack of space on the site. By supplying oxygen, the treatment capacity can be increased significantly in the existing facilities. The oxygen is added via oxygenation tubes.