Degrémont is a company specializing in the production of drinking water, and in the treatment of sewage and sludge. After starting as a family business in France in 1939, it has since become a subsidiary of Suez Environment, employing 4,600 people in 70 countries, and generating annual revenues of €1.520 billion . Wikipedia.


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Patent
Air Liquide, Association De Gestion De Lecole Francaise De Papeterie Et Des Industries Graphiques Agefpi, Degremont, Xylem Water Solutions Herford GmbH and Arkema | Date: 2014-06-13

This invention relates to a method for treating chemical paper pulp comprising a step of treating the pulp with ozone followed by a step of alkaline extraction, in which alkaline extraction takes place in the presence of magnesium ions (Mg^(2+)).


Process for treating effluents containing nitrogen in ammonium form, using a sequential biological reactor (1), according to which: a volume of effluents to be treated in one complete cycle is introduced into the biological reactor in one or more successive fractions by volume, each fraction by volume being treated during a subcycle; each subcycle comprises a phase of feeding with a fraction by volume, and at least a first aerated step, during which total or partial oxidation of the ammonium to nitrites takes place by injection of air or of oxygen into the effluent, a settling out and emptying step taking place after the end of the complete cycle; the weight of NNH_(4 )to be treated is determined from the volume of effluents in the reactor at the end of the feeding phase, and from the difference between the initial NNH_(4 )concentration in the reactor and a concentration desired at the end of the aerated step, a maximum aeration time TM is dedicated to the aerated step, and an initial air flow rate Qairinit, for the beginning of the aerated step, is determined by taking into account the weight of NNH_(4 )to be treated and the maximum aeration time TM.


A method and facility for the hydrothermal carbonization of pasty products or waste, or sewage sludge, in a pressurized reactor heated to carbonization temperature T0. Before entering the reactor, the products undergo: pressurization, and preheating in an exchanger, by a thermal fluid flowing in a closed loop, and receiving heat from products exiting the reactor; the thermal fluid is heated in the loop by an external heat source, downstream from the exchange with the products exiting the reactor, and upstream from the preheating of the products entering the reactor, and the temperature of the product to be treated, preheated by the thermal fluid, when it enters the reactor, is between the carbonization temperature T0 and T0-100 C. The product to be treated flows in at least one tube, where in at least one location therein, liquid is injected to create a liquid ring against the inner wall, and reduce pressure drops.


The present invention is directed to systems and methods of treating wastewater. The present invention may include a method of treating such wastewater comprising selenium in the form of water soluble selenates, selenites, and/or selenides, the method including: a chemical/biological treatment process, causing the water soluble selenates, selenites, and/or selenides in the wastewater to be converted into insoluble elemental selenium; and a physical treatment process, trapping the insoluble elemental selenium in a filtration device. Systems and methods in accordance with the present invention may also include a system for including: one or more chemical/biological treatment reactors, the one or more chemical/biological treatment reactors configured to cause the water soluble selenates, selenites, and/or selenides in the wastewater to be converted into insoluble elemental selenium; and one or more physical treatment devices, the one more physical treatment devices configured to trap the insoluble elemental selenium in a filtration device.


Patent
Degremont | Date: 2014-10-03

A continuous ozone generator includes: at least two electrodes with a dielectric medium placed therebetween, the electrodes defining discharge gaps; an input end for circulating an oxygen-loaded gas to an output end; at least one electrode being made up of at least two segments, placed one behind the other in the direction of the flow of the gas; elements for cooling the electrodes, and elements for supplying electrical current to establish voltage between the electrodes and cause discharges within the gaps where the gas flows. The segments of the electrode are divided into at least two electrically separate groups, and the electrical current supply elements include at least two separate electrical supply stages, respectively corresponding to each segment group, thus ensuring that power is provided by each stage while taking into consideration the local ozone concentration, while power supply optimization elements are provided to, respectively, control each electrical supply stage.


The present invention is generally directed to the use of an ozone oxidation process to remove azoles and azole-type compounds from wastewater. Specifically, the present invention is directed to a chemical treatment system for wastewater, including: an oxidation module receiving wastewater input and outputting an effluent; wherein the oxidation module removes azole-type compounds from the wastewater; and wherein the effluent has a reduction in azole-type compounds greater than ninety percent (90%). In accordance with some embodiments, the present invention provides an oxidation module receiving as inputs: wastewater received from a chemical mechanical polishing process and ozone gas received from an ozone generator; the oxidation module outputting an effluent; wherein the oxidation module removes azole-type compounds from the input wastewater; wherein the effluent has a reduction in azole-type compounds greater than ninety percent (90%); and wherein the oxidation module does not require ferrous treatment or solid-liquid separation before treatment.


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 [NNO_(3)] 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.


A method for the forced dewatering, by pressing, of saline residues produced by drinking water production, or by the treatment of municipal or industrial wastewaters, in which method the saline residues are introduced into the cylinder (12a) of a piston press (12) comprising flexible drains (12e) formed by flexible sheaths from a material that is permeable to liquid but impermeable to solids, each drain (12e) comprising an inner passage that opens into an associated opening (12g), the press operating in batches, and characterised in that during pressing, the piston carries out reciprocal movements and applies alternating and variable pressures to the sludge, while the flexible drains are deformed, the liquid pressed out from the product passing through the wall of the drains and being discharged as a filtrate, while the dewatered sludge remains outside the drains and is discharged by opening the press.


The invention relates to a method for ultra-dehydrating thickened or pasty biomass products, in particular sludge from wastewater treatment plants, according to which the products, in particular products having a dryness of 4% to 25%, are subjected to the following steps: hydrothermal carbonisation treatment, including pressurization (1, 2) and thermal conditioning (30) for a duration in a closed reactor (4); followed by dehydration of the products by a ram press (12), obtaining a dryness of more than 50%; the temperature of the product upstream from the ram press dehydration being regulated by cooling between 40 C. and 90 C., advantageously to around 70 C., in order to optimise the filterability in the piston press; the steps of the method being performed in a confined space making it possible to prevent the release of smells into the atmosphere.


A method for biologically treating effluent involves pouring the effluent into a basin in which mobile supports are submerged for developing a biofilm and for carrying out a treatment by fixed fluidized bed, aerating the effluent in the basin with a distribution of air flow, from the bottom of the basin, according to a floor configuration, the aeration supplying air for treating the nutrients, and keeping the supports moving, regulating the aeration to modulate the air flow depending on at least one parameter taken from the following parameters: the residual oxygen concentration, and/or the concentration of oxygen and the concentration of NNH4, and/or the permitted load; modifying the distribution of the air supply from the floor configuration to a spiral flow configuration when the operating conditions result in an air flow lower than a minimum air flow required to keep the mobile supports moving in the floor configuration.

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