Patent ID: 7357870
Filing Date: 2008-04-15
Classification: C02F,Y02W

Abstract:
1. A method for reducing the amount of wastewater treatment station sludge, comprising the steps: purifying the wastewater with fixed biological cultures from which excess sludge is extracted intermittently during phases of washing; sending the water coming from each washing phase that provides fixed biological cultures to a solid/liquid separator from which a quantity of sludge is extracted; subjecting by biological activated sludge treatment, said extracted quantity of sludge, the outlet of this stage not recycling effluent to the front end of a water treatment line of the wastewater treatment station; subjecting part of effluent coming from the biological activated sludge treatment to a stage of reduced sludge production (RSP) by thermophilic enzymatic action or by partial oxidation by ozone introduced by mechanical stirring, this stage of RSP being supplied by quantities of sludge from the step of biological treatment by activated sludge, the substrate source for the bacteria of the biological treatment including organic material derived from lysed bacterial cells induced during the RSP stage.