Abstract: A system for aerating a submerged membrane is provided. The system includes: a device for supplying compressed air; at least one orifice for aerating the submerged membrane; a pipe for feeding air from the air supplying device to the at least one aeration orifice; a first valve for opening or closing an orifice between the pipe and the surrounding air; a pressure sensor configured to measure the pressure in the pipe. The system is configured to perform at least one iteration of an operation to evacuate solid materials from the pipe, the said evacuation including at least: stopping supplying compressed air in the pipe and opening the first valve, causing reduction of the pressure in and penetration of liquid into the pipe; closing the first valve and resuming supplying compressed air in the pipe causing an increase in the pressure in and expulsion of liquid from the pipe through the at least one aeration orifice.

Abstract: Apparatus for clarifying a sludge-containing effluent, comprising a clarification basin (2), at least one arm (7) able to move over the upper surface of the liquid in the basin; at least one trough (8) supported by the arm so that it can be immersed over part of its height in the liquid of the basin, suction tubes (T1, T2) held relative to the trough, each tube comprising at the top a vertically adjustable sleeve (B1, B2) opening into the trough, and a means of removing sludge from the trough; the sleeve (B1, B2) of at least one suction tube (T1, T2) is free to slide vertically relative to the mobile arm (7) supporting the trough, and to the tube (T1, T2) and a reserve of buoyancy necessary and sufficient for keeping the overspill end (E1, E2) of the sleeve in the trough (8) continuously out of the water is installed on the sleeve (B1, B2) so that the overspill level of the sleeve adjusts automatically in relation to the level (16) of liquid and sludge in the trough.

Abstract: Apparatus for clarifying a sludge-containing effluent, comprising a clarification basin (2), at least one arm (7) able to move over the upper surface of the liquid in the basin; at least one trough (8) supported by the arm so that it can be immersed over part of its height in the liquid of the basin, suction tubes (T1, T2) held relative to the trough, each tube comprising at the top a vertically adjustable sleeve (B1, B2) opening into the trough, and a means of removing sludge from the trough; the sleeve (B1, B2) of at least one suction tube (T1, T2) is free to slide vertically relative to the mobile arm (7) supporting the trough, and to the tube (T1, T2) and a reserve of buoyancy necessary and sufficient for keeping the overspill end (E1, E2) of the sleeve in the trough (8) continuously out of the water is installed on the sleeve (B1, B2) so that the overspill level of the sleeve adjusts automatically in relation to the level (16) of liquid and sludge in the trough.

Abstract: The invention relates to a pulsed sludge bed settling method for treating all types of liquid, in particular water, and which uses at least one powder or grain reactant, according to which: the liquid and the reactant(s) for the treatment are contained in a tank (1) comprising, at the base thereof, a means (2) for uniformly feeding liquid to be treated over the entire surface thereof; the treated liquid is discharged into the top portion of the tank, at the top level (S) of the liquid; the liquid to be treated is supplied into the tank by pulsations, inducing alternating vertical movements of the sludge bed (M); and part of the sludge is spilled into a concentrator (12) when the top level of the sludge bed exceeds a spilling level (Ld).

Abstract: The invention concerns a method for purifying wastewater loaded with organic matter, said method including: a step of contacting wastewater with a biological culture containing a purifying biomass and a step of separating performed by filtration through organic or inorganic membranes. The invention is characterized in that at least part of the biological culture is subjected to an oxidative stress step enabling a liquor to be obtained by the action of at least one oxidizing agent used in small amount so as to preserve the biological activity of the purifying biomass while modifying the microbial floc to make it denser.

Abstract: Advanced control method for a membrane filtration unit, applied to the treatment of an effluent, employing microcoagulation on a membrane, which consists in injecting, upstream of the membrane, a dose of coagulation reactant(s) 30 to 80 times below the dose (X) making the zeta potential of the effluent zero, in which method: quantities defining the quality of the effluent to be treated and quantities defining the state of membrane clogging are measured as input variables; the operating point of the microcoagulation process is located on the basis of the results of the above measurements; thresholds for the input variables are determined, the microcoagulation having to be initiated when said thresholds are violated; and the coagulation reactant(s) is(are) injected depending on the results of the measurements and on the comparison of the input variables with the respective thresholds.

Abstract: The invention relates to a method for treating fluids, in particular waste waters involving coagulation/flocculation, clarification by filtration or flotation stages and a stage of filtration through micro-, ultra, and nanomembranes or of hyperfiltration. The inventive method consists in injecting two times several coagulating reagents in a quantity ranging from 75 to 125% of an optimal coagulation dose or a dose cancelling a Zeta potential (pz) in an area (area n° 1) situated upstream of the clarification stage (2) and from 0.1 to 25% of an optimal dose cancelling the pz in a second area (area n° 2) situated upstream of the stage of membrane filtration (4).

Abstract: The invention relates to a method for the optimised management of a membrane filtration unit based on membrane micro-coagulation, that comprises at least one measurement of the effluent temperature (7), one measurement of the filtration flow rate (8), and one measurement of the trans-membrane pressure (9). The injection of the coagulation reagent(s) is controlled by a unit (U) when the membrane permeability becomes lower than a threshold value, and the interruption of the coagulation reagent(s) injection is controlled when the membrane permeability is again equal to or higher than the stable LpO value before the drop, during a predetermined hold time.

Abstract: The invention concerns a method for purifying wastewater loaded with organic matter, said method including: a step of contacting wastewater with a biological culture containing a purifying biomass and a step of separating performed by filtration through organic or inorganic membranes. The invention is characterized in that at least part of the biological culture is subjected to an oxidative stress step enabling a liquor to be obtained by the action of at least one oxidizing agent used in small amount so as to preserve the biological activity of the purifying biomass while modifying the microbial floc to make it denser.

Abstract: The invention relates to an effluent treatment installation which can be used to improve the filtration capacity of membranes and to reduce water losses without increasing the floor area thereof. For said purpose, the invention comprises a pulsed sludge blanket settling tank (1) containing membrane filtration modules (10) which are submerged in or above the sludge blanket, and the system (11) for extracting the treated effluents is connected upstream of said filtration modules (10). The invention also relates to a method for clarification by means of coagulation/flocculation/decantation and for filtration using said installation.

Abstract: The invention relates to a method for treating fluids, in particular waste waters involving coagulation/flocculation, clarification by filtration or flotation stages and a stage of filtration through micro-, ultra, and nanomembranes or of hyperfiltration. The inventive method consists in injecting two times several coagulating reagents in a quantity ranging from 75 to 125% of an optimal coagulation dose or a dose cancelling a Zeta potential (pz) in an area (area n° 1) situated upstream of the clarification stage (2) and from 0.1 to 25% of an optimal dose cancelling the pz in a second area (area n° 2) situated upstream of the stage of membrane filtration (4).

Abstract: A method for treating waste water uses a membrane bioreactor that produces excess biological sludge and treated water components. This is achieved by extracting the biological sludge from the bioreactor then causing contact between the biological sludge and dewatered effluent to form two resulting products. The first product contains polyclectrolyte loaded sludge. Polyelectrolyte is continually added to the polyelectrolyte loaded sludge during dewatering to separately form dewatered sludge and the dewatered effluent. This is followed by extracting, as a second product, polyelectrolyte free effluent. The polyelectrolyte free effluent is recycled to the bioreactor.

Abstract: The invention relates to a method for avoiding, or reducing the clogging of filtration membranes, in particular, as used in effluent treatment such as of aqueous wastes, characterised in comprising the addition, to the effluent for filtration, of a natural organic adsorbent for trapping the molecules and particles which clog the filtration membranes.

Abstract: The invention relates to a membrane bioreactor waste water treatment method comprising a sludge dewatering step and a step involving the recycling of the liquid effluent originating from the sludge dewatering step, which is performed at the head of the bioreactor. The invention is characterised in that: the biological sludge extracted from the bioreactor (1) is brought into contact with the liquid effluent from the sludge-dewatering step such that the residual polyelectrolyte content in said effluent, which was used for sludge conditioning during the dewatering step (4), moves towards the biological sludge; the biological sludge is separated from the liquid effluent such as to produce a polyelectrolyte-free liquid effluent and a polyelectrolyte-loaded biological sludge; the polyelectrolyte-free liquid effluent is recycled at the head of the membrane bioreactor, and the polyelectrolyte-loaded biological sludge is conveyed towards the dewatering step.

Abstract: A method for membrane filtration of effluent water containing suspended matter reduces membrane clogging and improves filtration capacity of the membrane. The method includes adding a dose of a preselected coagulation reactant to the effluent before the effluent passes over the membrane. The added dose is a fraction of the coagulating reactant dose (X) that would render the zeta potential of the effluent equal to zero. The range of the added dose is X/30-X/80. The suspended matter in the effluent is subjected to the added dose of coagulation reactant for destabilizing the suspended matter.