Abstract: The invention concerns a method for treating water to abate their content in suspended matter and, as the case may be in parasites, characterised in that it consists in causing said water to pass through at least one sedimentation tank (1) at a treatment speed higher than 20 mph then, through at least a multilayer filter with decreasing size grading (2) at a treatment speed higher than 10 mph. The sedimentation tank used is preferably a sedimentation tank with ballasted floc preferably lamellar.

Abstract: The invention relates to a process of aqueous phase oxidation of effluents, consisting of subjecting said effluents to oxidation in the presence of at least one catalyst and of at least one oxidising agent, at a temperature of between approximately 20.degree. C. and approximately 350.degree. C., under a total pressure of between approximately 1 and approximately 160 bars, in such manner as to mineralise part of the organic matter and total ammoniated nitrogen contained in said effluents, said oxidation being carried out inside a reactor in which a gaseous phase is set up above the liquid phase consisting of said effluents.characterized in that said catalyst is a heterogeneous catalyst placed inside said reactor above the interface between said gaseous phase and said liquid phase.

Abstract: A process of aqueous phase oxidation of effluents, consisting of subjecting the effluents to oxidation in the presence of at least one oxidizing agent inside a reactor having a gaseous phase set up above a liquid phase consisting of the effluents, and subjecting the gaseous phase to catalysis in the presence of at least one heterogeneous catalyst. The oxidation process is carried out at a temperature of between approximately 20.degree. C. and approximately 350.degree. C. under a pressure of between approximately 1 and 160 bars. At least a part of the organic matter and total ammoniated nitrogen contained in the effluents are mineralized. The process includes recycling at least a part of the gaseous phase present in the oxidation reactor after the gaseous phase has passed through the heterogeneous catalyst so as to effectively increase the contact time between the gaseous phase and the heterogeneous catalyst in order to obtain substantial removal of NH.sub.3, COR, and volatile organic compounds.

Abstract: An integrated method for purifying industrial and/or urban effluents containing a large amount of organic material in solution and/or suspension, wherein said effluents are treated in a wet oxidation reactor. The effluents are oxidized in the presence of at least one oxidizing gas to mineralize a large part of the organic material therein by producing a gas phase and an essentially liquid phase mainly containing soluble residual organic material, as well as an essentially inorganic solid phase in suspension. The essentially liquid phase from the reactor is subjected to liquid/solid separation to separate the solid phase, and at least a fraction of the separated solid phase is recycled in the wet oxidation reactor. Various alternative embodiments of the method include adding a catalyst and/or an agent for acidifying the recycled solid phase fraction. The facility may operate continuously or semi-continuously between interruptions.

Abstract: This invention relates to a plant for the biological treatment of water to produce drinking water, characterized in that it comprises at least one biological reactor (7) provided with injection means (9) for injecting oxygenated gas, at least one separation membrane (11 for microfiltration or ultrafiltration immersed in said reactor (7), and addition means (10) for adding to said reactor (7) at least one pulverulent material in suspension serving as a support for a biomass, said pulverulent material possibly being a reactive powder which also allows fixation of the substrate required by said biomass.

Abstract: A plant for the treatment of surface water comprises a safety barrier mounted at the exit from the treatment plant and constituted by a physical filter providing, at the exit from the filter, a predetermined minimum quality irrespectively of the quality of the water on entry into the filter, and a pre-treatment installation located upstream from the safety barrier, the treatment intensity of the pre-treatment installation being adjusted as a function of the characteristics of the surface water to be treated through measuring devices located at the entrance to the physical barrier. The safety barrier is advantageously a nanofiltration membrane, coupled if necessary to one or more reverse osmosis membranes mounted downstream in "series-rejection" mode. The disclosed installation can be applied to the treatment of water liable to show great variability in quality, notably to the treatment of surface water or of water with equivalent characteristics.

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.