Abstract: A water-treatment installation, notably with a view to making water potable, includes a reactor demarcating at least one treatment chamber, the reactor comprising a conveying assembly to convey the water to be treated into the chamber; a removing assembly for removing the floated pollutants and a removing assembly for removing the decanted pollutants; a plurality of filtration membranes laid out within the chamber and submerged in the water to be treated; a demarcating assembly for demarcating a filtration zone around each of the membranes; carrying and circulating member guiding a current of water to be treated in the filtration zone along a preferred direction, the carrying and circulating member including ozone-injection assembly; and a recovering assembly recovering the permeate at an outlet of the filtration membranes.

Abstract: To purify untreated water, for example waste water, containing organic pollution, materials in suspension and nitrogen-containing pollution, reagents are added under conditions adapted to coagulate all of the materials in suspension, including colloidal materials, to form granular physical/chemical floc. Diluting water is added, preferably after the reagents, in a flowrate ratio of at least 2/1. The dilute flocculated water is caused to flow through a bed of sludge in the form of such dense and granular floc and denitrifying bacteria. The bed is subject to turbulent but intermittent agitation. A denitrified effluent is recovered. This denitrified effluent is caused to flow through a biological filter or preferably through a fluidized bed containing nitrifying bacteria and into which oxygen or air is injected. A clarified effluent is obtained, some of which is recycled as the diluting water.

Abstract: A process for the biological treatment by nitrification and/or denitrification of an effluent containing nitrogen pollution includes the following steps:an incident flow of this water is brought into a mixing zone with at least one compartment in which, by turbulent mechanical agitation, an inconsumable and insoluble granular material, loaded with biomass, is put in homogeneous suspension in this water, and is maintained at a more or less constant mass concentration;this water and this granular material in suspension are circulated in a separation zone from which is extracted on the one hand clarified water, and on the other hand biomass loaded granular material; andalmost all of the active biomass fixed on said granular material is brought back by forced recycling to the mixing zone.

Abstract: Method of treating liquid by sedimentation in which reagents are injected into a flow of untreated liquid and there is created in the flow a colloid mixing and stabilization area; the flow is passed into an intermediate aggregation area and then into a sedimentation area equipped with separator plates from which clarified liquid is taken; characterized in that insoluble granular material which is more dense than the liquid is injected into the liquid in predetermined proportions in the mixing area where the flow is made turbulent, turbulence is induced in the intermediate aggregation area to maintain the granular material in suspension, virtually all of the granular material is brought into the sedimentation area, the sludge recovered in the sedimentation area is removed, the granular material is removed therefrom (D) and is recycled after cleaning.

Abstract: Water is purified according to the principle of a biomass fixed on an aerated granular bed acting as a filter in a biological reactor.The water to be purified is sent, without presettling, upwardly through a multilayer granular bed placed in the reactor. The injection point of oxygenated gas determines two succesive zones, anaerobic and then aerobic. The water is evacuated from the reactor at the top thereof, or at a certain level of the bed. A sudden downward flushing of the filter with water is provided to eliminate the biomass. The filter is periodically washed with air/water and then rinsed with water.

Abstract: Reactor having considerable volume or surface for injection and distribution of a gaseous fluid into a liquid mass to be treated, includes a false bottom having over its entire surface a series of nozzles each having a small orifice, incorporated with a pipe, immersed in the liquid, whose perforated base rests on the false bottom and whose closed upper end is provided with slots from which gas bubbles escape into an active zone of the liquid mass.