METHOD FOR MINIMISING THE NEW WATER USE IN THE WATER CIRCULATION SYSTEM OF A TREATMENT PLANT

摘要

A system and method for minimizing new water use in the water circulation system of a treatment plant in which the matter to be treated is purified and/or disaggregated using water in a treatment step. The suspension containing the remaining components is subjected to mechanical purification and the mechanically purified suspension is separated into two processing water streams. The first processing water stream is supplied back into the treatment step and the second processing water stream is subjected to a chemical-physical clarification. The chemically-physically clarified processing water stream is separated into two clarified water streams. The first clarified water stream is led into one of the two processing water streams and/or into the suspension and the second clarified water stream is subjected to a biological clarification. The biologically clarified water stream, being a fresh water stream, is led into one or two clarified water streams. The ratio of the processing water streams to the clarified water streams has been predetermined depending on the matter that is supplied to the treatment step and on the type of mechanical purification and the type of chemical-physical clarification used.