Abstract: A method for the real-time estimation of the total consumption of a fluid, in particular water or gas, distributed from a unit (A) to users (b1, b2 . . . ) via a network of supply pipes (E) with a branch (d1, d2 . . . ), for each user, fitted with a counter (c1, c2 . . . ) of the fluid consumed by the user, which method involves defining cohorts of users having homogeneous behavior with regard to the consumption of fluid; defining, for at least one of these cohorts, a sample of users from the cohort that is statistically sufficient to represent the cohort; fitting only the branches of the users of each sample with a remote reading device (t1, t2, . . . ) for reading the consumption; also fitting remote reading devices to the branches of the users of the other cohorts that have not been sampled; and processing the information provided by the remote reading devices to obtain a real-time value representative of the total consumption of the network.

Abstract: The invention relates to a method for extracting heat from an effluent (2) circulating in a conduit (1), especially a waste water collector, according to which a heat exchanger (E) is installed, at least in the bottom of the conduit, said heat exchanger (E) lying in the effluent and being formed by coating tubes (3) with sufficiently heat-conductive concrete cast around the tubes intended for the circulation of a heat-transfer fluid, the heat exchange with the effluent of the conduit being carried out through the moulded coating. The concrete (4) of the coating consists of a least 50 weigh % of silicon carbide, a load of needles made of a heat-conductive and mechanically resistant material, a binding agent and the remainder of alumina, metal powder or carbon.

Abstract: A heat exchanger system extracts heat from sewer waste water. Preferably, a first surface is narrow band in an interior surface of a pipe, and the band is preferably oriented transverse to a direction of fluid flow. In the case of a horizontal pipe, the band may be a partial band, and may be limited substantially to a wetted portion of the pipe in order to reduce the size of the band.

Abstract: Method for extracting heat from an effluent flowing in a duct (2), in particular a wastewater collection device. In said method, a heat exchanger (E) that is submerged in the effluent is mounted at least on the bottom of the duct, the heat exchanger (E) being formed by coating tubes (3) with a material that is sufficiently heat-conducting, is poured around the tubes, and hardens in situ. A heat transfer fluid flows in the tubes (3), the heat being transferred from the effluent in the duct through the molded coating, the upper surface of the poured material being in direct contact with the effluent flowing in the duct, but not with any inserted mechanical part.; The coating is composed of multiple layers having different material properties, i.e.

Abstract: Disclosed is a system for extracting heat from an effluent duct (2), in particular a wastewater collection device, comprising, in the zones of the inner duct wall located above the effluent, heat exchanger tubes (3) which are exposed to the atmosphere in the duct and through which a heat transfer fluid flows to recover some of the sensible heat and of the latent condensation heat from the steam generated by the effluent. A forced-convection device (9) is provided to generate a movement of air sweeping across the surface of the effluent (1) and increase the evaporation rate of the effluent.

Abstract: A water supply pipe has a tubular liner of a polyolefin elastomer/plastomer installed therein. The polyolefin elastomer/plastomer includes a substantially linear ethylene inter-polymer with a narrow molecular weight distribution from 1.8 to 2.2.

Abstract: A water supply pipe has a tubular liner of a polyolefin elastomer/plastomer installed therein. To install it, a messenger pig is attached to a line that pulls the liner through the pipe. The liner is produced by extrusion and die drawing during extrusion.

Abstract: This invention relates to means of qualitative and quantitative analysis of microbial populations potentially present in a sample. These means notably comprise the use of at least one RNA-targeted oligonucleotide probe for in situ hybridization in whole cells; followed by the extraction of those probes which have become hybridized by separation from their target and elution from the microbial cells; as well as the detection and measurement of said extracted probes.

Abstract: A water supply pipe has a tubular liner of a polyolefin elastomer/Plastomer installed therein. The polyolefin elastomer/plastomer includes a substantially linear ethylene inter-polymer with a narrow molecular weight distribution from 1.8 to 2.2.

Abstract: Device for use in rehabilitation of water supply pipes includes a tubular liner (10) which is deployed through a pipe (11) for example by a line attached to a messenger pig which is propelled through the pipe. The liner (10) has a multi-lobed pleated cross-section, and is of a polyolefin elastomer material, e,g, a substantially linear ethylene inter-polymer. The liner is extruded and die drawn during extrusion to produce a reduced diameter highly oriented structure.

Abstract: Process for controlling the retention time of the sludge undergoing clarification in a process for treating wastewater by activated sludge comprising a recirculation of the activated sludge from the clarification stage into the biological basins, characterized in that the rate of sludge recirculation (Qr) is varied so as to maintain a constant recirculated sludge concentration (Cr) while at the same time guaranteeing a retention time (RT) of the sludge undergoing clarification of less than a critical value (RTmax).

Abstract: A process is disclosed for regulating the aeration in a biological wastewater treatment plant using a carbon removal stage, a nitrification stage and a denitrification stage. The process includes the step of continuously measuring the value of oxidation-reduction potential of the treated medium as well as measuring oxygen concentration of the treated medium during aeration phases. This permits maintaining aeration if the oxygen concentration falls within a preselected reference range. Alternately there is reduction of the aeration if the oxygen concentration is above the preselected reference range, or increasing the aeration if the oxygen concentration falls below the preselected reference range.

Abstract: An apparatus for the separation of a solid/liquid suspension by filtration includes a tank filled with a suspension to be treated. At least one cavitied plate is located in the tank and has at least one internal cavity. The plate is immersed in the suspension to be treated. The plate is inclined with respect to the vertical and only a lower inclined face of the plate is covered with a filter medium, the upper face being solid. The compartment of the cavitied plate communicates with a conduit which collects filtered suspension. Gas flushing pipes are positioned below the plate for emitting gas bubbles that pass across the filter medium and remove material clinging thereto.

Abstract: A Method for regulating the disinfection of a liquid includes a number of stages. At one stage of the said disinfection (stage 2), the activity of at least one enzyme is measured by bringing the microorganisms which may be present in the liquid into contact with a substrate capable of revealing the activity of the enzyme, this enzymatic activity being referred to as specific activity. At another stage (stage 1), prior to stage 2, there occurs measuring the activity of the same enzymes. This activity being referred to as initial activity. The next stage involves translating, for each enzyme, the specific activity and initial activity, into levels of microorganisms surviving in the liquid at stage 2 of the disinfection by means of a reference system pre-established with the aid of a sample of the liquid collected at stage 1 and then exposed to increasing doses of disinfectant.

Abstract: This method uses the on/off sequences of an aeration system of treatment basins. The sequences are imposed by the running of a treatment process, to estimate the respiration of biomass, the latter being measured during non-aeration phases. There is an initial determination, from the concentration of dissolved oxygen, of the change in the amount of oxygen contained in the aeration basin. There is a subsequent determination of the amount of oxygen leaving the aeration basin, the amount of oxygen entering the basin during the non-aeration phase being regarding as zero. Next is a determination, on the basis of the information collected in the above steps, of the respiratory capacity of the purifying biomass. There is then a determination of the mass of suspended matter in the purifying biomass and calculation, from the respiratory capacity of the biomass and from the sludge concentration, of the amount of oxygen consumed per unit mass of biological sludge and per unit time.

Abstract: A process is disclosed for monitoring the integrity of hollow fiber filtration modules and for detecting leaks of treated liquid through a fiber completely or partially broken. It operates continuously and in filtration mode, without production shutdown. The process includes detecting the noise caused by the passage of the liquid through a ruptured fiber. The noise signal thus obtained is amplified. The amplified signal thus obtained is compared with a threshold noise level, within the same range of frequencies, which is characteristic of intact modules, this comparison making it possible to detect whether or not the module is intact.

Abstract: A method of monitoring and managing biomass stock of treatment plants employs activated sludge. An aeration basin receives an effluent and a concentration of suspended matter in the basin is measured. A change in concentration is then analyzed and a maxima of this concentration is determined which corresponds to periods of hydraulic underperformance. A total biomass mass is estimated, and the rate of extraction of biomass is adjusted.

Abstract: Method of monitoring the efficiency of the aeration systems of biological basins of a wastewater treatment plant, characterized in that it consists in: i) measuring the throughput (Qt) of the plant and the rate (Qr) of recirculation of the mixed liquor from the clarifier to the aeration basin; and ii) measuring the concentration of dissolved oxygen in the aeration basin so as: a) to establish, during an aeration period, the material balance between oxygen supplied, oxygen consumed and oxygen discharged with the effluent; b) to establish, during a non-aeration period, the material balance between oxygen consumed and oxygen discharged with the effluent; c) to determine the amount of oxygen consumed by the biomass based on the two material balances established above; and d) to determine, from the data obtained at a), b) and c) , the value of the transfer coefficient &agr;kLa under the conditions of the measurement.

Abstract: A method of purifying waste water biologically, in which at least one biological reaction is performed in at least one biological reactor containing microorganisms in activated sludge, and the waste water is separated from the activated sludge in a clarification basin, with at least a fraction of the activated sludge from said biological reactor being recirculated, wherein, prior to admitting the waste water to be treated into said biological reactor, at least a fraction of the polluting particles in suspension therein are separated out therefrom, the separated polluting particles are sent to a sludge activation reactor that is separate and disposed in parallel, the separating polluting particles are used as the main substrate for the development of microorganisms in strict aerobiosis, and the superactivated sludge obtained in this way is injected into the biological reactor(s).

Abstract: A method of regulating aeration in biological treatment of wastewater by implementing a step of eliminating carbon in aerobiosis, a step of nitrification in aerobiosis, and a step of denitrification in an anoxia, in which method the oxidation-reduction potential is continuously measured in a treatment system, a curve is established of variation in oxidation-reduction potential as a function of time, and the derivative thereof is calculated, wherein, when the derivative tends towards zero, the derivative and the value of the oxidation-reduction potential are correlated to determine whether aeration should be started, continued, or stopped.