FR3053035B1 - INSTALLATION FOR RECYCLING GRAY WASTEWATER FROM A BUILDING TO FEED WATER HUNTS - Google Patents

Abstract

Recycling plant (1) for treating wastewater (3) from bathrooms or kitchens of a building, and for producing filtered and treated water (7), comprising at least: - at least one main entrance (E), - a treatment circuit (11) for producing a treated water (15), and - a post-filtration unit (13) adapted to filter the treated water (15) and produce the treated and filtered water (7), the treatment circuit comprising: - a disinfection unit (35), - a coagulation unit (45), - at least one filtration unit (39) to obtain the treated water, - a test unit (41) for measuring one or more parameters representative of the quality of the treated water, and - a distribution system (43) adapted to store the treated water and tested in the treatment circuit (11) or send it to the post-filtration unit (13) as a function of the measured parameter (s).

Description

INSTALLATION FOR RECYCLING GRAY WASTEWATER FROM A BUILDING TO FEED WATER HUNTS

The present invention relates to a wastewater recycling plant adapted to treat wastewater from a building. The building is for example a collective dwelling, a hotel, an industrial establishment, or a tertiary establishment, such as a hospital or an aquatic center. Generally, all wastewater produced in such a building is sent to a sewerage system for treatment. The building is supplied with water by a drinking water system. The drinking water of the networks is most often obtained by treatment, often expensive, from spring water, lake or river. This rather expensive water feeds the whole building: kitchens, bathrooms, toilets ... etc.

The costs of clean water supply and wastewater treatment are therefore relatively high.

In addition, it would be technically possible to treat wastewater locally to obtain drinking water again. However, the necessary installation would be bulky and expensive in terms of investment and operation. In addition, it is possible that the water obtained, deemed potable, does not inspire confidence users, being obtained from highly polluted water. Such a solution is therefore not very viable.

An object of the invention is therefore to provide an installation for reducing the costs of supplying clean water and wastewater treatment of the building. To this end, the invention relates to a water recycling facility adapted to treat wastewater from bathrooms or kitchens of a building, and to produce treated and filtered water for feeding hunts of water, the installation comprising at least: - at least one main entrance to receive the wastewater to be treated, - a treatment circuit for receiving, as input, water from the main entrance and producing a treated water, and - a post-filtration unit adapted to filter the treated water and produce the treated and filtered water, the treatment circuit comprising: - a disinfection unit adapted to release into the water received at least one product disinfectant, - a coagulation unit to release into the water received at least one coagulant or flocculant product to produce in the water received agglomerates containing bacteria or dead viruses, - at least one filtration unit adapted to filter the water from the coagulation unit and obtain the treated water, - a test unit adapted to measure one or more parameters representative of the quality of the treated water, and - a system splitter adapted to retain the treated water and tested in the processing circuit or send it to the post-filtration unit according to the measured parameter (s).

According to particular embodiments, the installation comprises one or more of the following characteristics, taken in any technically possible combination: the installation further comprises a protective enclosure housing the disinfection unit, least a part of the coagulation unit, the filtration unit, the test unit, the distribution system and the post-filtration unit, the protective enclosure preferably having a floor area of less than or equal to 20 m2; the installation further comprises a prefiltration unit connected to the main inlet for receiving the wastewater to be treated and for producing prefiltered water, and connected to the inlet of the treatment circuit for sending the pre-filtered water to the treatment circuit; treatment, the prefiltration unit preferably comprising at least one self-cleaning filter; the filtration unit comprises at least one self-cleaning filter and is preferably devoid of a filtering membrane; the post-filtration unit comprises a cartridge filter; the post-filtration unit comprises an outlet pipe for treated and filtered water from the cartridge filter, a shut-off valve of the outlet pipe, and a pressure switch adapted to measure a parameter representative of the pressure. treated and filtered water in the outlet pipe, the pressure switch being adapted to close the shut-off valve according to the parameter and to telemetry a request for maintenance of the cartridge filter, the pressure switch being preferably intended to trigger a supply of water from a mains water network according to the parameter; - The processing circuit further comprises a coloring unit adapted to release at least one coloring product in the water received; the parameters measured by the test unit are one or more of pH, rH, turbidity, conductivity and color; the installation also comprises a telemetry system adapted to measure one or more of representative parameters: a consumption of wastewater by the installation; a consumption of city water by the installation, - a changeover to a supply from a mains water network, - a clogging of the post-filtration unit, - a failure of a measuring device of the test unit, - failure of a pump of the treatment circuit, and - lack of water in the storage tank; the installation optionally comprises a first disinfection unit adapted to subject the water received in the treatment circuit to disinfectant UV radiation; the filtration unit and the prefiltration unit respectively comprise filters having a fineness of filtration less than or equal to 5 micrometers, preferably less than or equal to 2 micrometers, and even more preferably substantially equal to 1 micrometer; and the cartridge filter has a fineness of filtration less than or equal to 0.5 micrometer, preferably less than or equal to 0.3 micrometer, and even more preferably substantially equal to 0.2 micrometer. The invention also relates to a process for recycling wastewater from bathrooms or kitchens of a building, and to produce filtered and treated water for supplying flushing toilets, the method comprising minus the following steps: - reception of the wastewater to be treated and obtaining a water to be treated, - treatment of the water to be treated and obtaining a treated water, and - post-filtration of the treated water, to produce the treated and filtered water, the treatment step comprising the following sub-steps: a) disinfection by releasing into the water to be treated at least one disinfectant product, b) coagulation by releasing into the water to be treated at least one product coagulant or flocculant to produce, in the water to be treated, agglomerates containing bacteria or dead viruses, c) filtration of the water to be treated comprising the agglomerates and obtaining the treated water, d) measurement of a or more parameters representative of the quality of the treated water, and - (e) distribution of treated water (15) to treat treated water again in substeps (a) to (e) or to send water processed in the postfiltration step according to the measured parameter (s). The invention will be better understood on reading the description which follows, given solely by way of example and with reference to the appended drawing, in which the figure is a diagram of an installation according to the invention and whose operation illustrates a method according to the invention.

Referring to the figure, there is described a facility 1 for recycling wastewater according to the invention. The installation 1 is adapted to treat waste water 3 from bathrooms or kitchens of a building (not shown), advantageously collected in a tank 5. The installation 1 is able to produce treated and filtered water The building is for example a collective dwelling, a hotel, or an industrial or tertiary establishment, such as a hospital or an aquatic center.

Wastewater 3 is less polluted than other types of wastewater, which is why it is described as "gray". The installation 1 comprises a main inlet E for receiving the wastewater 3 to be treated, and a prefiltration unit 9 fluidly connected to the main inlet for receiving the wastewater to be treated. The installation 1 also comprises a processing circuit 11 connected at the input to the pre-filtration unit and forming a loop, and a post-filtration unit 13 adapted to receive as input treated water 15 from the treatment circuit and to produce treated and filtered water 7 at an outlet S of the installation. The installation 1 advantageously comprises a protective enclosure 16 housing the preprocessing unit 9, at least a part of the processing circuit 11, with the exception, for example, of a storage tank 17, and the post-processing unit. treatment 13. The protective enclosure has a footprint advantageously less than 20 m2. The installation 1 comprises a telemetry system 18 adapted to measure parameters of the installation 1 or the disconnection tank 20, and to send these parameters or certain remote requests for the operation of the installation 1.

The flushing 9 are connected, via a distribution system 17, on the one hand to the outlet S to receive the treated and filtered water 7, and on the other hand to a disconnection tank 20 to receive water 21 from a water source 23, for example a city water network.

Disconnection tray 21 is provided to supply water flush 9 when installation 1 does not work. The pre-filtration unit 9 is connected as input to a wastewater take-up pump 3. The pre-filtration unit 9 comprises an automatically cleaning filter 27 with a filtration fineness less than or equal to 5 μm, preferably less than or equal to 2 μm and even more preferably substantially equal to 1 μm. The prefiltration unit 9 is adapted to produce prefiltered water 29, and is connected to an inlet 31 of the treatment circuit 11 for sending pre-filtered water to this circuit.

The treatment circuit 11 optionally comprises a first disinfection unit 33 adapted to subject the water received in the treatment circuit to UV disinfectant radiation, a disinfection unit 35 adapted to release into the water received at least one disinfectant product, and a coagulation unit 37 for releasing into the water received at least one coagulant flocculant to produce in the water received agglomerates carrying dead bacteria or viruses. The treatment circuit 11 also comprises a filtration unit 39 adapted to filter the water coming from the coagulation unit and to obtain the treated water 15, a test unit 41 adapted to measure one or more parameters representative of the quality. treated water, and a distribution system 43 adapted to send the treated water and tested either at the input of the processing circuit, or to the post-filtration unit 13 depending on the measured parameter or parameters. The disinfection unit 35 comprises for example a metering pump equipped with a Redox regulator for injecting chlorine into the water received in order to prevent a new development of bacteria and viruses after treatment by the first disinfection unit. 33. The coagulation unit 37 comprises for example a metering pump 45 for injecting the coagulating or flocculating product, and the storage tank 17.

The storage tank 17 is advantageously self-cleaning. It is equipped with a cleaning and mixing nozzle 47, a drain valve 49, and a member 51 for discharging an overflow. The storage tank 17 further comprises an outlet 53 for water comprising the agglomerates. The filtration unit 39 is advantageously similar to the pre-filtration unit 9. The filtration unit 39 is connected to the outlet 53 of the storage tank 17 and produces the treated water 15. The filtration unit 39 comprises a self cleaning filter 40.

All the filters of the installation 1 are advantageously devoid of membranes (absence of filtration by permeation). The test unit 41 is connected to the filtration unit 39. The parameters measured by the test unit 41 are, for example, the pH, the rH, the turbidity, the conductivity and the coloration of the treated water 15. The test unit 41 comprises, in the example shown, four devices for measuring these parameters.

Dispatcher system 43 includes a first branch 55A adapted to conduct treated water from the output of test unit 41 to the inlet of treatment circuit 11 when the parameters of the treated water do not satisfy one or more predetermined criteria, and a second branch 55B adapted to conduct the treated water from the output of the test unit 41 to the post-filtration unit 13 when the parameters of the treated water meet the predetermined criteria or criteria.

The first branch 55A comprises a pump 57 (or water booster) allowing recycling of the treated water inside the treatment circuit 11, until the treated water reaches a predetermined quality. The post-filtration unit 13 comprises a cartridge filter 59, and an outlet pipe 61 comprising a shut-off valve 63 and a pressure switch 65 adapted to measure the pressure of the treated and filtered water 7 in the outlet pipe. .

The pressure switch 65 is adapted to close the shut-off valve 63 as a function of this pressure, and to telemetry (remote) a maintenance request for the cartridge filter 59 if the measured pressure falls below a predetermined threshold. The pressure switch 65 is also adapted to trigger a supply of water to the disconnection tank 20 from the source 23.

The cartridge filter 59 has a filtration fineness less than or equal to 0.5 μm, preferably less than or equal to 0.3 μm, and even more preferably substantially equal to 0.2 μm.

The telemetry system 18 is adapted to measure one or more of the following parameters: - a consumption of waste water 3 by the installation 1, - a consumption of water from the source 23 by the installation, a changeover to a supply from the source 23 (that is to say the interruption of the operation of the installation 1), a clogging of the post-filtration unit 13, a failure of a measuring apparatus of the test unit 41, - a failure of the pump 57, - a lack of water in the storage tank 17,

The operation of the installation 1 will now be described.

The wastewater 3 from the bathrooms and kitchens of the building are collected in the tank 5 and directed to the main entrance E of the installation 1.

The pump 25 sends the water to be treated in the filter 27 of the prefiltration unit 9. The pre-filtered water 29 is removed from the largest waste present in the water to be treated. The filter 27 automatically evacuates the waste retained and advantageously requires very little maintenance.

Then, the prefiltered water 29 enters the treatment circuit 11 through the inlet 31. The prefiltered water 29 passes through the first disinfection unit 33, where it undergoes irradiation with ultraviolet rays that kill germs (bacteria, viruses ) present in the water to be treated. The water to be treated then passes through the disinfection unit 35, which for example injects chlorine into the water to be treated in order to prevent a new development of germs. Advantageously, the disinfection unit 35 constitutes a staining unit 35A which also injects a food colorant into the water to be treated, in order subsequently to distinguish the treated water from untreated water.

Chlorine disinfects the water to be treated and all piping and systems in the installation 1.

The dye, for example a blue color, prevents users from using the treated and filtered water 7 for a different application than that provided for. The water to be treated then arrives in the coagulation unit 37. The metering pump 45 injects the coagulant or flocculant into the water to be treated to produce agglomerates in the water to be treated, the agglomerates containing seeds killed by the previous disinfections.

More specifically, the water comprising the coagulant or flocculant product is introduced into the storage tank 17 through the nozzle 47 which has the effect of cleaning and mixing. The water advantageously circulates permanently in the storage tank 17. The drain valve 49 allows a possible emptying of the storage tank 17. The member 51 makes it possible to evacuate any excess water in the storage tank 17 The water containing the agglomerates is recovered at the outlet 53 of the storage tank 17 and taken to the filtration unit 39, in which the agglomerates are removed to obtain the treated water 15. The treated water then passes through the test unit 41 and the representative parameters of quality of the treated water are obtained.

If the parameters obtained do not satisfy the quality criterion or criteria, the treated water is sent to the first branch 55A of the distribution system 43, and returns to the input of the treatment circuit 11 to undergo again the steps of disinfection, coagulation and filtration already mentioned. The pump 57 ensures recirculation in the loop thus formed.

If the quality parameters satisfy the predetermined criterion or criteria, the treated water is sent to the second branch 55B to enter the post-filtration unit 13.

The quality criteria are for example the following: - pH between 6 and 9, - residual chlorine between 0.5 and 1 ml per m3 of water, - amount of faecal coliforms equal to 0 CFU per 100 ml, - quantity total coliforms less than or equal to 100 CFU per 100 ml, - quantity of Escherichia coli less than or equal to 10 CFU per 100 ml, - quantity of pseudomonas aeruginosa less than or equal to 1 CFU per 100 ml, - MES equal to 0 mg / l .

In the post-filtration unit 13, the cartridge filter 59 removes the finest particles still present in the treated water 15.

When the filter cartridges become saturated, the pressure measured by the pressure switch 65 in the outlet pipe 61 decreases. When this pressure is below a predetermined threshold, the closing valve 63 is closed and the water supply to the disconnection tank 20 from the source 23 is initiated.

The dispensing system 19 is fed either by the treated and filtered water 7 coming from the outlet S of the installation 1, or by the water 21 coming from the disconnecting tank 20.

When the flush 9 are fed with treated water and filtered 7, the blue color of the latter deters the use of treated water and filtered for other uses.

The telemetry system comprises for example a digital screen 67 and touch.

The telemetry system 18 advantageously controls the consumption of water treated and filtered 7 by the flushing 9, as well as that from the source 23. It detects low levels of products in the disinfection unit 35 and in the the coagulation unit 45.

It also detects a possible lack of water in the wastewater storage tank 3 before treatment.

It also detects the transition to a supply from the source 23.

It detects a possible clogging of the cartridge filter 59, or measurement defects of the control devices of the test unit 41.

Finally, it detects a possible fault of the pump 57, and a possible lack of water in the storage tank 17.

Thanks to the characteristics described above, the facility 1 can treat wastewater 3, called "gray", which are of interest in that they are not very polluted. Thus, the installation 1 is relatively simple to build and implement, and has a low footprint. The treated and filtered water produced by the installation 1, without however being drinkable, has the advantage of being able to be used in particular in the flushing 9, without danger to health, in place of a water relatively expensive city. Thanks to its optional blue color, treated and filtered water 7 can not be confused with tap water.

Claims (10)

1. - Installation (1) wastewater recycling adapted to treat wastewater (3) from bathrooms or kitchens of a building, and to produce filtered and treated water (7) intended to supply flushing (9), the installation (1) comprising at least: - at least one main inlet (E) for receiving the wastewater (3) to be treated, - a treatment circuit (11) for receiving, at the inlet (31), water from the main inlet (E) and producing a treated water (15), and - a post-filtration unit (13) adapted to filter the treated water (15) and producing treated and filtered water (7), the treatment circuit (11) comprising: - a disinfection unit (35) adapted to release into the water received at least one disinfectant product, - a coagulation unit (45) ) to release in the water received at least one coagulant or flocculant product to produce in the water received agglomerates comprising b actéries or dead viruses, - at least one filtration unit (39) adapted to filter the water from the coagulation unit (45) and obtain the treated water (15), - a test unit (41) ) adapted to measure one or more parameters representative of the quality of the treated water (15), and - a distribution system (43) adapted to keep the water treated and tested in the treatment circuit (11) or to send it to the post-filtration unit (13) as a function of the measured parameter (s). 2. - Installation (1) according to claim 1, further comprising a protective enclosure (16) housing the disinfection unit (33), at least a portion of the coagulation unit (45), the unit of filtration (39), the test unit (41), the distribution system (43) and the post-filtration unit (13), the protective enclosure (16) preferably having a floor area of less than or equal to to 20 m2. 3. - Installation (1) according to claim 1 or 2, further comprising a prefiltration unit (9) connected to the main inlet (E) for receiving the wastewater (3) to be treated and to produce a prefiltered water ( 29), and connected to the inlet (31) of the treatment circuit (11) for sending the prefiltered water (29) to the treatment circuit (11), the prefiltration unit (9) preferably comprising at least one self-cleaning filter (27). 4. - Installation (1) according to any one of claims 1 to 3, wherein the filter unit (39) comprises at least one self-cleaning filter (40), and is preferably devoid of filter membrane. 5. - Installation (1) according to any one of claims 1 to 4, wherein the post-filtration unit (13) comprises a cartridge filter (59). 6. - Installation (1) according to claim 5, wherein the post-filtration unit (13) comprises an outlet pipe (61) for the treated and filtered water (7) from the cartridge filter (59). ), a closing valve (63) of the outlet pipe (61), and a pressure switch (65) adapted to measure a parameter representative of the pressure of the treated and filtered water (7) in the outlet pipe ( 61), the pressure switch (65) being adapted to close the shut-off valve (63) according to the parameter and to telemetry a maintenance request for the cartridge filter (59), the pressure switch (65) being preferably intended to trigger a supply of water from a mains water network according to the parameter. 7. - Installation (1) according to any one of claims 1 to 6, wherein the processing circuit (11) further comprises a coloring unit (35A) adapted to release at least one colorant in the water received . 8. - Installation (1) according to any one of claims 1 to 7, wherein the parameters measured by the test unit are one or more of pH, rH, turbidity, conductivity and coloring . 9. - Installation (1) according to any one of claims 1 to 8, further comprising a telemetry system (8) adapted to measure one or more of representative parameters: - a wastewater consumption (3) by the installation (1), - consumption of city water by the installation (1), - a passage to a supply from a city water network, - a clogging of the post-filtration unit (13), - a failure of a measuring device of the test unit (41), - a failure of a pump (57) of the treatment circuit (11), and - a lack of water in the storage tank (17). 10. -Recycling process for treating wastewater (3) from bathrooms or kitchens of a building, and for producing filtered and treated water (7) for feeding flushing toilets (9) the process comprising at least the following steps: - receiving the wastewater (3) to be treated and obtaining a water to be treated, - treating the water to be treated and obtaining a treated water (15), and - post-filtration of the treated water (15), to produce the filtered and treated water (7), the treatment step comprising the following substeps: a) disinfection by releasing into the water to be treated at least one disinfectant product, b) coagulation by releasing into the water to be treated at least one coagulant or flocculant product to produce, in the water to be treated, agglomerates containing bacteria or dead viruses, c) filtration of the water to be treated containing the agglomerates and obtaining the treated water, d) measuring one or several parameters representative of the quality of the treated water, and e) distribution of the treated water (15) for subjecting the treated water (15) again to substeps a) to e) or to sending the treated water treated water (15) in the postfiltration step according to the measured parameter (s).