Abstract: A method and apparatus for treating wastewater. The apparatus comprises a reactor having a flow channel generally centrally located in a reactor and immersed in the water or wastewater in the reactor. An agitator is disposed within the flow channel and induces water or wastewater to enter the open upper end thereof and to move downwardly through the flow channel where the water or wastewater is discharged via a flow divider. A reagent is injected into the water or wastewater and the agitator within the flow channel serves to mix the reagent with the water or wastewater passing therethrough and in the process causes at least a slightly turbulent and downward axial flow through the flow channel.

Abstract: A process for treating water is provided where the water is mixed with an inorganic reagent powder such as powder activated carbon. Organics and micropollutants are absorbed by the reagent powder. After the reagent powder has been mixed with the water, the water is directed to a setting tank and sludge from the water settles to produce a clarified effluent. Forming a part of the sludge is the reagent powder previously added. Sludge is collected and directed to a separator that separates the reagent powder from the sludge. Separated reagent powder is recycled and mixed with the water being treated.

Abstract: A method and apparatus for treating wastewater. The apparatus comprises a reactor having a flow channel generally centrally located in a reactor and immersed in the water or wastewater in the reactor. An agitator is disposed within the flow channel and induces water or wastewater to enter the open upper end thereof and to move downwardly through the flow channel where the water or wastewater is discharged via a flow divider. A reagent is injected into the water or wastewater and the agitator within the flow channel serves to mix the reagent with the water or wastewater passing therethrough and in the process causes at least a slightly turbulent and downward axial flow through the flow channel.

Abstract: The invention relates to a method for removing impurities from an aqueous stream. The method includes directing the aqueous stream into an adsorbent contact zone and contacting the aqueous stream with an adsorbent material in the adsorbent contact zone so that impurities in the aqueous stream are adsorbed onto the adsorbent material. The aqueous stream and the adsorbent material is then directed to a ballasted flocculation zone where the adsorbent material is mixed with ballast to form sludge. The aqueous stream is then separated from the sludge to produce treated water and the sludge is settled in a settling zone. The ballast is then separated from the sludge and directed to the ballasted flocculation zone while the sludge and the adsorbent material are directed to a transition zone.

Abstract: A device for disinfecting water by ultraviolet radiation. The device includes two discharged lamps that are connected by electrical wires. A first electrical circuit is disposed in the immediate vicinity of the discharge lamps and controls a warm-up phase of the discharge lamps. A second electrical circuit is disposed remotely from the discharge lamps and functions to control an operational phase of the discharge lamps.

Abstract: A process for the removal of liquid, gaseous and/or dissolved constituents from a process stream. The process stream is contacted with an adsorbent comprising a first porous material which has been incorporated into a second porous material at least 30 vol. % of the pores of the first and second porous materials of which are filled with an extraction liquid. The affinity between the adsorbent and the constituents to be removed exceeds the affinity between the constituents and the extraction liquid.

Abstract: A method and apparatus for treating wastewater. The apparatus comprises a reactor having a flow channel generally centrally located in a reactor and immersed in the water or wastewater in the reactor. An agitator is disposed within the flow channel and induces water or wastewater to enter the open upper end thereof and to move downwardly through the flow channel where the water or wastewater is discharged via a flow divider. A reagent is injected into the water or wastewater and the agitator within the flow channel serves to mix the reagent with the water or wastewater passing therethrough and in the process causes at least a slightly turbulent and downward axial flow through the flow channel.

Abstract: The invention relates to a lamellar decanting module comprising two interconnected plates, at least one of said plates being corrugated in such a way that the dips and peaks are inclined in relation to a first edge of said plate according to a non-zero degree angle and define inclined decanting tubes with the other plate. Said module is characterised in that the two plates (2, 3) have the same corrugated profile and are interconnected in connection regions defining a plane of symmetry (P) for the tubes (4) defined by said plates. A plurality of modules can be assembled in such a way as to form a block in which the plates are parallel to one of the faces.

Abstract: The invention relates to a method and installation for treating water for human consumption, for an industrial process, for agricultural purposes or for other purposes. The method used to remineralize raw water comprises a stage in which carbon dioxide and at least one inorganic base are injected. According to the invention, the method comprises the following stages: the flow Q of raw water is separated into a flow Q1 and a flow Q2; only flow Q1 is remineralized by injecting carbon dioxide and at least one inorganic base, said remineralization being carried out in at least one remineralization basin; remineralized flow Q1 is mixed with untreated flow Q2.

Abstract: The invention concerns a method for treating water for human consumption, so as to eliminate manganese and possibly other metals comprising steps which consist in: causing said water to pass at least over a bed of filtering material (3) consisting at least partly of manganese dioxide granules, said granules having a real density ranging between 3.5 and 4.5 and a hardness higher than 6 on the Mosh scale; regenerating, if necessary, said manganese dioxide, said regeneration being carried out mechanically.

Abstract: The invention concerns the use of a coagulation-flocculation-decantation device for water treatment to degrease water inside the device itself so as to eliminate therefrom more than 20% of hexane-extractable matter without resorting to separate degreasing means by flotation. The invention also concerns a plant comprising a coagulation-flocculation-decantation device by ballasted flocs having a coagulation zone (1), means supplying (4) a granular material denser than water (4), a flocculation (6), a decantation zone (8) and means for recycling (15) granular material including at least a hydrocyclone (17). The characterised in that it does nut comprise degreasing means provided upstream of the coagulation-flocculation-decantation device, the grease being removed from the water inside the coagulation-flocculation-decantation device itself without means for injecting air or an equivalent gas.

Abstract: The invention relates to a lamellar decanting module comprising two interconnected plates, at least one of said plates being corrugated in such a way that the dips and peaks are inclined in relation to a first edge of said plate according to a non-zero degree angle and define inclined decanting tubes with the other plate. Said module is characterised in that the two plates (2, 3) have the same corrugated profile and are interconnected in connection regions defining a plane of symmetry (P) for the tubes (4) defined by said plates. A plurality of modules can be assembled in such a way as to form a block in which the plates are parallel to one of the faces.

Abstract: A process and system for treating excess sludge produced from a biological treatment system. The process includes biologically treating water or wastewater and producing excess sludge. The excess sludge is directed to a solubilizer where the sludge is solubilized. The solubilized sludge is directed to a liquid/solid separator, which separates the solubilized sludge into a liquid fraction and a solid fraction. The process further includes at least partially digesting the liquid fraction and directing the partially digested liquid fraction to the biological treatment system where the liquid fraction is subjected to further treatment. Finally, the solid fraction is subject to further solubilization.

Abstract: A method is provided for thickening sludge produced through a ballasted flocculation process. The sludge and granular material from the ballasted flocculation process are directed to a sludge separator where the sludge is separated from the granular material. Thereafter the separated sludge is sent to a degassing area and the sludge is degassed. A flocculating agent is mixed or injected into the sludge. The sludge is directed to a sludge thickener with a load at a sill calculated on the surface of the thickener greater than 200 kgMIS/m2/day. This process produces a thickened sludge having a concentration greater than 10 gm/I.

Abstract: The invention relates to a method for the thermal hydrolysis of sludge characterized in that it is carried out in at least two reactors operating in parallel, in each of which the sludge undergoes a complete thermal hydrolysis cycle. Said cycle comprises different stages consisting in supplying the reactor with the sludge, injecting live stream in order to bring said sludge to a pressure P and a temperature T at which hydrolysis can occur, maintaining the sludge at said pressure P and said temperature T for a certain amount of time, suddenly bringing said sludge to the atmospheric pressure by releasing the flash steam and emptying said reactor of the hydrolysed sludge. Furthermore, the inventive method consists in time shifting the cycle of one reactor to the other in order to use the flash steam produced from one reactor to inject it into the other reactor.

Abstract: The invention concerns a water treatment method which consists in introducing coagulated water in a flocculation zone, to enable flocculation of microflocs in the presence and around a ballast; introducing the mixture in a decantation zone; separating the treated water in overflow and a mixture of sludge and the ballast in underflow; conveying at least part of said mixture to a sludge/ballast separating system and recycling into or upstream of the flocculation zone the ballast and part of the sludge introduced in said separation system.

Abstract: The invention concerns an installation for measuring the concentration in dense granular material in a flow comprising a liquid, a dense granular material and suspended fine particles. The invention is characterised in that it comprises: at least a member for separating the dense granular material from the liquid and the suspended fine particles, at least a device for measuring (12, 12a, 13) at least a parameter representing the amount of separated dense granular material for a specific time interval T. Such an installation may be integrated in a ballasted-floc water treatment system.

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.