Abstract: A method for utilizing spent grain in a brewery in which the spent grains are mechanically dewatered and then thermally utilized. The press water arising from the mechanical dewatering is thermally concentrated using low-temperature waste heat generated during the brewing process.

Abstract: A method reprocesses waste water containing an organic acid from an industrial process. A base is added to the acid-containing waste water. A salt dissolving in the waste water is produced due to a neutralization reaction. The waste water is subsequently guided in a heat exchanger process, a heat exchange medium being used such that the waste water which is to be treated is partially evaporated and is condensed into purified water on a condensation device. A concentrate enriched with the salt forms a residue and the purified water is guided back into the industrial process.

Abstract: Waste water from an industrial process, including an organic acid, is reprocessed by introducing the waste water into a heat exchange process in which a heat exchange medium is used so that the waste water which is to be treated is heated to a temperature between 60° C. and the boiling point of the waste water. Subsequently, the waste water is partially evaporated and re-condensed, with the waste water irradiated with UV radiation during the evaporation and condensation process in the liquid and/or gas phase. As a result, a chemical transformation of the organic acid in H2O and carbon dioxide is at least partially carried out. Then, the condensed part of the purified waste water is fed back into the industrial process.