Abstract: A device for treating an effluent composed of liquid and of solid particles to obtain a treated effluent includes a filtration device using gravity separation on a rotating cloth having an inlet intended to receive the effluent to be treated and a first and a second outlet, the filtration device being designed to separate the effluent into a first flow and a second flow, the second flow comprising sludges comprising solid particles, the first flow leaving the filtration device through the first outlet, the second flow leaving the filtration device through the second outlet, and at least one recirculation device designed to recirculate at least a part of the sludges of the second flow to the inlet of the filtration device, the second outlet being linked to the at least one recirculation device. A method for treating an effluent is also provided.

Abstract: A device for treating an effluent composed of liquid and of solid particles to obtain a treated effluent includes a filtration device using gravity separation on a rotating cloth having an inlet intended to receive the effluent to be treated and a first and a second outlet, the filtration device being designed to separate the effluent into a first flow and a second flow, the second flow comprising sludges comprising solid particles, the first flow leaving the filtration device through the first outlet, the second flow leaving the filtration device through the second outlet, and at least one recirculation device designed to recirculate at least a part of the sludges of the second flow to the inlet of the filtration device, the second outlet being linked to the at least one recirculation device. A method for treating an effluent is also provided.

Abstract: A method for biologically denitrifying waste water, includes a nitrification-denitrification sequence followed, for a first fraction of water, by a post-denitrification step during which an electron donor is injected into the first fraction, while a second fraction of water passes through a bypass, then is mixed with the first fraction downstream of the post-denitrification step; the first fraction of waste water is subjected, during the post-denitrification, to a nearly complete denitrification so as to exit the step at a nitrate [N—NO3] concentration less than 4 mg/L, to minimize nitrous oxide production. The bypass rate is determined based on: a measurement of the nitrate concentration of the water upstream of the post-denitrification, the desired nitrate concentration for the mixture of the two fractions downstream of the post-denitrification treatment, and the nitrate concentration of the first fraction at the outlet of the post-denitrification, before the mixing of the two fractions.

Abstract: Disclosed is a facility for treating waste water of municipal or industrial origin, in particular a facility for primary treatment of the water, including a biological contact tank equipped with biological rotating discs, which is connected upstream of a ballasted-floc physiochemical decanter, the decanter being at least made up of a coagulation zone, a flocculation zone, a lamellar decanting zone and a thickening zone and an external circuit allowing the recirculation of the sludge thickened in the thickening zone to the flocculation zone and the biological contact tank.

Abstract: A method for biologically denitrifying waste water, includes a nitrification-denitrification sequence followed, for a first fraction of water, by a post-denitrification step during which an electron donor is injected into the first fraction, while a second fraction of water passes through a bypass, then is mixed with the first fraction downstream of the post-denitrification step; the first fraction of waste water is subjected, during the post-denitrification, to a nearly complete denitrification so as to exit the step at a nitrate [N—NO3] concentration less than 4 mg/L, to minimize nitrous oxide production. The bypass rate is determined based on: a measurement of the nitrate concentration of the water upstream of the post-denitrification, the desired nitrate concentration for the mixture of the two fractions downstream of the post-denitrification treatment, and the nitrate concentration of the first fraction at the outlet of the post-denitrification, before the mixing of the two fractions.

Abstract: The invention relates to a process for treating water in an installation comprising a plurality of filtration units, said process comprising at least one step of filtration of said water in said filtration units under initial filtration conditions, and an optional step of modification of the value of at least one controlled parameter within a tolerance interval.