Facility for treating wastewater and building comprising such facility

Abstract

The invention relates to a plant (1) for treating wastewater (EM) from a building (2). This installation comprises means for collecting waste water (EM); a plant purification treatment module (6) positioned on the roof (21) of the building (2) and configured to convert the wastewater (EM) into purified water; and means (10) for recirculating purified water, preferably treated water (ET), into at least one internal or local circuit (B1) for reusing said treated water (ET) inside or near said building (2), and / or for discharging said treated water (ET), in default or due to excess, into an external network (B) for disinfecting or treating waste water.

Description

[0001] The present invention belongs to the field of water purification. More specifically, the present invention relates to a facility for treating waste water from a building, and to a building comprising such a facility.

[0002] With today's growing urban population, wastewater treatment is a constant priority health issue. Specifically, the growth of urban populations is increasing the amount of wastewater to be treated in urban purification systems. In addition to this, water resources are becoming increasingly scarce and the cost is increasing.

[0003] In addition, the increasing number of buildings in towns and their "concreteization" leads to waterproofing of the ground, which, especially in case of heavy rainfall, and especially for a single network, allows large amounts of water to flow quickly into the purification system.

[0004] These large wastewater flows from urban populations, as well as special climate events such as droughts or heavy precipitation, have an impact on the operation of urban wastewater treatment and purification infrastructure, especially water treatment plants.

[0005] As a result, these water treatment infrastructures are becoming increasingly complex for the collection, transport and purification of wastewater, especially household wastewater. It has been found that the risk of saturation of these infrastructures and the risk of overflow of purification systems are increasing, especially in urban areas.

[0006] In particular, urban areas are growing, urbanization is accelerating, and existing purification infrastructures have become undersized. Two solutions can be envisaged: either resize them (involving investments of billions of euros) or try to limit the volumes delivered to public central purification plants.

[0007] Therefore, there is a need to find a simple solution for managing and treating wastewater that is suitable for urban environments in order to limit the damage to the current wastewater management and purification infrastructure.

[0008] Furthermore, within the ecologically responsible logic of sustainable development and protection of the Earth's resources, the current trend is to recycle as much available wastewater as possible, in particular for use in the context of appropriate hygiene requirements (especially less stringent), such as in building sanitary flushing or for irrigation of crops or green areas (e.g. France: Decree of June 25, 2014 amending the Decree of August 2, 2010 on the use of water originating from the purification of municipal wastewater for irrigation of crops or green areas).

[0009] The term "wastewater" corresponds to "raw water" that flows directly from public or private buildings. Wastewater is formed by domestic wastewater, known as "grey water", and black water, known as "sewage".

[0010] "Black water" comes from toilets and washrooms in buildings. Black water is formed by a mixture of solid components, especially fecal matter, and liquid or dissolved components in a liquid medium, especially urine.

[0011] "Domestic" or "grey" water is mainly generated by showers, wash basins, washing machines and dishwashers installed in these buildings. Grey water is slightly polluted and in particular free of faeces or urine. As a result, there is considerable potential for reusing domestic water, in particular for sanitary flushing systems or for irrigation or watering of green areas.

[0012] Therefore, the treatment and recycling of wastewater, especially domestic wastewater (if possible, locally), poses a major challenge to protecting water resources and limiting the negative impacts of high-density human activities, especially in urban areas where the amount of wastewater (especially domestic wastewater) generated is large.

[0013] There are already various domestic wastewater treatment systems that allow its direct redistribution to urban buildings. These building wastewater treatment systems comprise at least one device for recovering said water, followed by a device for treating said water and a device for redistributing it to sanitary toilets, irrigation or crop watering networks.

[0014] However, these known wastewater treatment systems typically:

[0015] - a complex structure with many transmission pipes and storage or treatment tanks, which proves to be complex in managing the transfer, supply and distribution of the wastewater to be treated within the purification network;

[0016] - the bulkiness of the structure, which is then deployed on the ground or inside a building, which results in the space thus occupied in and adjacent to the building being unusable for another purpose,

[0017] - high operating energy consumption, especially for actuating the supply valves, circulating through the treatment filters, and transferring and storing the water,

[0018] - high manufacturing and installation costs,

[0019] - is visually unsightly and detracts from the building's exterior and / or interior appearance within the urban landscape.

[0020] Furthermore, known building wastewater treatment systems require regular maintenance checks, particularly in view of the effects of freezing / thawing on their functioning, and the risk of saturation or even blockage of pipes or filters when the wastewater inflow is too large.

[0021] Known systems having at least some of the above mentioned limitations are disclosed, for example, in the following documents: CZ306199, FR 3105208, US 7754079 and US 2009 / 001002.

[0022] Therefore, there is currently an unmet need for an improved device for treating wastewater from buildings, in particular domestic wastewater or grey wastewater thereof, which device allows the water to be recovered and safely used for flushing toilets in the building or for watering green areas, which device is simple in structure, occupies little or minimal space, is easy to maintain and manage, has no negative impact on the environment, and has an acceptable or even visually attractive appearance in the urban landscape.

[0023] A primary object of the present invention is to respond at least partially, and preferably substantially completely, to the above needs.

[0024] To this end, the present invention relates to a plant for treating building wastewater, characterized in that the plant comprises:

[0025] - Wastewater collection plants,

[0026] - a pre-treatment module configured to convert said wastewater into pre-treated water,

[0027] - a phyto-purification treatment module positioned on the roof of the building and configured to transform the pre-treated water into purified water,

[0028] - means for storing said purified water, advantageously equipped with microbiological disinfection means configured to transform the purified water into treated water, and

[0029] - means for recycling the purified or, where appropriate, treated water into at least one internal or local circuit for reuse of said purified or treated water in or around said building, and / or for discharging said purified or treated water, by default or due to excess, into an external purification or sewage network,

[0030] The processing module includes at least one saturated / unsaturated flow planted filter.

[0031] The wastewater treatment facility of the present invention has a simplified structure and requires little time and resources for management and maintenance by an operator, especially for the phytopurification treatment module which has an almost autonomous operation over time.

[0032] Furthermore, the space occupied by the facility of the invention inside a building is limited, in particular due to the installation of the treatment modules on the roof by phyto-purification and the limited number of storage devices. The volume occupied by the facility of the invention inside a building is therefore optimized to limit its deployment to valuable areas of the building, advantageously suitable for another use.

[0033] Furthermore, in addition to the wastewater to be treated, the phyto-purification treatment module on the roof of the facility of the invention also allows the direct and simple collection of rainwater to create a buffer zone, improve the thermal insulation of the building, even the acoustic insulation of the building, and enhance the aesthetic appeal of the building by giving it a "green" mark and an ecological stamp by installing a planted area on the roof. This vegetated area (in the form of a planted aquatic environment) also provides the building with special insulating and cooling properties at roof level. Due to its specificity, it also contributes to urban biodiversity.

[0034] Furthermore, the installation of the invention allows limiting energy consumption and construction costs by recycling a large part of the wastewater, especially domestic wastewater. In particular, by limiting or avoiding the use of drinking water for purposes that do not involve direct contact with humans, it is possible to reduce the consumption of this resource, which is currently becoming more expensive and needs to be conserved.

[0035] In a similar ecologically responsible manner, the installation of the invention contributes to the depolution and freshening of the atmosphere in the vicinity of buildings and to the improvement of the urban landscape, in particular through the presence of plants from the phyto-purification treatment modules on the roofs.

[0036] The facility of the invention thus forms a simple and efficient device for treating building wastewater, allowing it to be recycled and reused locally as a water and hydraulic resource, for example, with priority being given to reusing the treated water in or around the building (in particular, for example in the building's sanitary toilet network), in any facility for cleaning vehicles, the building or its surroundings, or in an irrigation or watering network (optionally automated) for surrounding green areas or plants installed on balconies.

[0037] The facilities of the present invention are also environmentally friendly. The facilities of the present invention combine aesthetic appeal with ecologically responsible design and are designed to protect the earth's water resources without compromising the safety, comfort and water needs of the population, especially those in densely populated areas.

[0038] The invention will be better understood with the aid of the following description, which relates to preferred embodiments and variants given by way of non-limiting examples and explained with reference to the accompanying drawings, in which:

[0039] [ Figure 1] represents a schematic perspective view of a building equipped with a wastewater treatment facility according to the present invention,

[0040] [ Figure 2 ] represents a schematic functional view of a household water treatment facility of the present invention,

[0041] [ Figure 3 ] is a schematic top view of an embodiment of a plant purification treatment module,

[0042] [ Figure 4 ] means along Figure 3 A schematic cross-sectional view of AA of a plant purification water treatment module shown in,

[0043] [ Figure 5 ] is formed Figure 3 and Figure 4 A perspective view of an overflow device showing a portion of a module.

[0044] In the present patent application, the term "building" primarily and preferably denotes a collective building, such as an apartment building, a tertiary industry or a professional building, but may also refer to an individual building, such as a detached house.

[0045] Similarly, the term "domestic water" means slightly contaminated water from showers, sinks, washing machines and dishwashers, free from faeces or urine contamination, generally in liquid form, but which may have solid components such as food or organic waste / residues, hair, body hair, or natural or synthetic fibers.

[0046] The term "pretreated water" means water that has undergone pretreatment (advantageously by mechanical filtration) to remove coarse solids or sticky matter (especially also excess grease and oil) in flotation or suspension. Depending on the nature and quality of the wastewater to be treated, such pretreatment may or may not be useful or necessary.

[0047] Similarly, the term "purified water" means water that has been pretreated and has undergone a phytopurification treatment after passing through a phytopurification treatment module. Phytopurification is a water purification treatment involving the decontamination of water by suitable plants and by microorganisms associated with the root systems of these plants. Examples of how phytopurification can be performed are described in particular in documents US 6277274, FR 2942791 and WO2021 / 018629.

[0048] The term "treated water" here means water purified in a storage device after application of a microbiological disinfection device. For the application of the invention in France, the microbiological quality of the treated water complies with the standards set by the Regional Health Agency (ARS) and the decree of August 2, 2010 on the use of water derived from the purification of urban wastewater for irrigation of crops or green areas, and the French decree of January 11, 2007 on the limit values ​​and quality reference values ​​for raw water and drinking water for human consumption mentioned in articles R.1321-2, R.1321-3, R.1321-7 and R.1321-38 of the French Public Health Code. In the context of the application of the invention in another country, the microbiological quality of the treated water ET will meet the local current regulations and hygiene standards by adapting the device of the invention, which adaptation is within the reach of a person skilled in the art having knowledge of the invention.

[0049] In general, and regardless of the country in which the invention is implemented, the "treated water" obtained at the end of the treatment in the installation 1 has at least the concentrations of pollutants and microorganisms permitted by the following conditions:

[0050] - direct discharge into the environment (irrigation or irrigation) without risk of contaminating the environment, in particular the water table, and / or

[0051] - Return to the residential network and as a supply for toilet flushing where authorised by local regulations.

[0052] like Figure 1 or Figure 2 As shown, the invention relates to a treatment plant 1 for waste water EM from a building 2, characterized in that the plant comprises:

[0053] - Wastewater EM collection device 3,

[0054] - a pretreatment module 4, configured to transform said wastewater EM into pretreated water EP,

[0055] a phyto-purification treatment module 6 positioned on the roof 21 of the building 2 and configured to transform the pre-treated water EP into purified water EE,

[0056] - means 8 for storing said purified water EE, advantageously equipped with a microbiological disinfection device 9 configured to transform the purified water EE into treated water ET, and

[0057] - means 10 for recycling purified water EE or, where appropriate, treated water ET in at least one internal or local loop B1 for reuse of said purified water EE or treated water ET in or around said building 2 and / or for discharging said purified water EE or treated water ET, by default or due to an excess, into an external purification or sewage network B,

[0058] The phyto-purification treatment module 6 comprises at least one planted filter 62 with saturated / unsaturated flow.

[0059] The treatment plant 1 has a simple structural configuration with a reduced number of devices, but is still able to convert wastewater EM, especially domestic wastewater, at least into purified water EE, preferably into treated water ET with sufficient microbiological quality for internal use both in the building and its surrounding area.

[0060] The phyto-purification treatment modules 6 (constituting the elements occupying most of the ground area) are mounted on the roof 21. Therefore, since the treatment facility 1 is preferably deployed mainly on the top of the building (flat roof 21), its deployment on the ground is limited, which, in addition to providing green space at roof level 21, also facilitates the freeing up of space and the possibility of developing natural areas in the urban landscape near the building. On the contrary, by installing only the phyto-purification treatment modules 6 on the roof, the roof structure and the supporting elements of the building are not overstressed. In particular, the pretreatment modules 4 (and their buffer storage tanks 42) and the storage device 8 and optionally also other elements of the facility 1 (in addition to the modules 6) can be arranged in a room or equivalent space 1' in the basement of the building 2 comprising the facility 1 (see Figure 1 and Figure 2 ).

[0061] The hydraulic operating principle of the or each planted filter 62 is of the unsaturated / saturated type. During the supply phase, water flows vertically and by gravity into the pores of the gravel pack 622 planted with plants 623 of the filter device 62 in question until the pores of the pack are saturated at a variable height depending on the amount of water to be treated. Saturation in combination with the hydraulic retention time contributes to the purification performance of the planted filter 62.

[0062] When the treatment is completed (by measuring the residence time), the planted filter 62 under consideration is completely or partially drained, thereby allowing its reoxygenation. Alternating filling and emptying phases (preferably combined with a feed tank supply) allow the oxygenation conditions in the filter to be varied and thus aerobic / anaerobic conditions favorable to the treatment to be created in the filter. A more precise description of this mode of operation of the planted filter 62 implemented in the context of the present invention is given below.

[0063] In addition to protecting the environment by reusing available water resources, the treatment facility 1 ensures the quality of the treated water for a given application. The treatment facility 1 also helps to improve the quality of the urban atmosphere and helps to reduce pollution and improve the aesthetics of the urban landscape, in particular by allowing plants to develop and grow on the roofs of buildings.

[0064] The facility 1 comprises a pretreatment module 4 and storage means 8. Furthermore, in order to ensure water circulation between the various functional components of the facility 1, the facility may comprise, in addition to the wastewater EM collection means 3, means 5 for transferring pretreated water EP and / or means 7 for collecting and conveying purified water EE.

[0065] Specifically, by using gravity pre-filtration and free-flow filtration through planted filters, both functions require only limited energy consumption (lift-off).

[0066] According to an advantageous embodiment of the invention, also from Figure 1 and Figure 2 As is evident from the above, facility 1 more precisely includes:

[0067] - means 3 for collecting waste water EM, in particular at least domestic waste water EM, which are configured to feed the pre-treatment module 4,

[0068] - means 5 for transferring the pre-treated water EP (coming from the module 4 ) to the phyto-purification treatment module 6 , these transfer means 5 advantageously comprising at least one self-cleaning lifting pump 51 combined with a lifting column 52 ,

[0069] - means 7 for collecting the purified water EE and conveying it to a storage device 8 equipped with means 9 for microbiological disinfection in order to transform the purified water EE into treated water ET,

[0070] - a device 10 for recycling the treated water ET into at least one loop B1 as a supply to at least one device for flushing toilets in the building 2 and / or for watering or irrigating crops (for example plants, window boxes and / or cultivated green areas or landscaping areas located in or around the building 2), and / or for discharging the treated water ET into an external purification or sewage network B (i.e. usually a public sewage network).

[0071] Preferably, the device 5 for transferring the pretreated water EP to the plant purification treatment module 6 is configured and controlled to perform a water tank supply to the (multiple) planted filters 62, and the device 7 for collecting the purified water EE and conveying it to the storage device 8 is configured and controlled to perform a partial or complete emptying of the purified water EE from the (multiple) planted filters 62 in a controlled manner or at regular intervals corresponding to a preprogrammed residence time, thereby causing the above-mentioned alternating stages of filling and emptying of the plant purification treatment module 6.

[0072] According to a possible feature of the invention, Figure 1 and Figure 2 As can be seen in the figure, the pre-treatment module 4 (preferably located in the lower part or cellar of the building 2, for example in a technical room 1' in the basement together with the storage tank 8 and possibly at least part of its ancillary equipment) comprises:

[0073] at least one separation device 41 configured to separate the wastewater EM from solid waste, in particular food or organic waste, such as a self-cleaning separation filter, where appropriate a vortex filter, and

[0074] - at least one wastewater EM storage device 42, optionally equipped with mechanical filtering means 43, such as a pre-filtration drum equipped with ventilation holes and overflow openings to the sewage network B, the discharge of which is preferably directed by gravity to the transfer device (5).

[0075] The pre-treatment module 4 is positioned in the lower part of the building 2, is easily accessible to operators, in particular for inspection purposes, and allows collecting wastewater from the upper levels of the building 2 simply by gravity, without the need for additional energy-intensive moving equipment.

[0076] Furthermore, placing the pretreatment module 4 inside the building 2 protects it from weather and climatic factors, in particular freeze-thaw phenomena, and allows it to be preserved over time.

[0077] In particular, the positioning of the pre-treatment module 4 in the lower part of the building 2 facilitates the discharge of the solid food-grade waste, after the separation operation via the separation device 41 , directly into the drainage network provided for this purpose.

[0078] According to the invention, the separation device 41 physically and mechanically separates the solid waste from the liquid wastewater EM. Various devices known to those skilled in the art for performing this separation can be used.

[0079] According to one embodiment compatible with the preceding example, the separation device 41 comprises at least one self-cleaning separation filter. This allows a rough separation of the transported solid waste from the liquid fraction of the wastewater EM, in particular of the food waste type.

[0080] After separation by the separation device 41, the solid waste is introduced into the sewage system B by any known suitable means, and the wastewater EM is introduced into at least one storage device 42 by any known means, such as pipes or channels.

[0081] According to the invention, the at least one storage device 42 is intended for storing the wastewater EM before transferring it to the phyto-purification treatment module 6. For example, the storage device may consist of a storage tank or a storage barrel.

[0082] According to a particular embodiment compatible with the preceding example, the storage device 42 is equipped with mechanical filtering means 43 allowing additional filtering of the wastewater EM and separation of the wastewater EM from solid waste. Furthermore, this storage device 42 is constructively configured to prevent the development of flies, mosquitoes and other pests.

[0083] like Figure 2 As shown, the storage means 42 are for example composed of a pre-filtration vat 42 equipped with at least one mechanical separation filter 43 of the granular filter type allowing the wastewater EM to be separated from the solid food waste by vertical filtration through the granular material.

[0084] According to the present invention, the mechanical separation filter 43 is configured to separate the waste water EM from its solid waste more finely than the separation device 41 .

[0085] According to an example of implementation of the treatment facility 1 compatible with the previous examples, the facility 1 may comprise dispersion and surface distribution means 61 for the pre-treated water (EP) at the level of the phyto-purification treatment module 6. Furthermore, it is conceivable that the transfer means 5 comprise at least one self-cleaning lift pump 51 combined with a lifting column 52 leading to said dispersion and surface distribution means 61, which preferably ensure a substantially uniform distribution over the entire surface area of ​​the module 6. These means 61 may consist, for example, in a non-limiting manner, of extended angle nozzles.

[0086] According to a particular embodiment, the lifting column 52 is configured and dimensioned so as to allow the creation of a Venturi effect during the transfer of the pretreated water EP to the phyto-purification treatment module 6, so as to produce an oxygenation of the pretreated water EP within the lifting column 52. This oxygenation creates microbubbles in the pretreated water EP and also allows a homogenization of its transfer and distribution speed within the lifting column 52, so as to discharge this water with a uniform distribution and flow through the dispersion device 61.

[0087] According to a particular embodiment of the invention, the dispersing device 61 consists of at least one diffusion system. Figure 3 As shown, the diffusion system consists of a network of diffusion ramps leading to diffusion nozzles arranged to cover the entire surface of the phytopurification treatment module 6 with the pre-treated water EP and thus in a uniform manner.

[0088] According to an example of implementation of the facility 1 that is compatible with the aforementioned provisions, the phyto-decontamination module 6 (positioned on the roof 21 of the building 2) comprises:

[0089] - at least one planted filter 62 with combined vertical direct+horizontal flow (or also indicated as unsaturated-saturated flow), the supply of pretreated water EP to this / these filters being performed, for example, by means 61 for dispersion and surface distribution (means 61 = sprinkler nozzles distributed over the surface of the planted filter(s) 62 and supplied by a suitable pipe network - Figure 3 ), and

[0090] - Overflow device 63.

[0091] The planted filter 62 may include a single gravel pack 622 or alternatively at least two gravel packs 622, for example arranged and fed in parallel, or arranged in series.

[0092] The phytosanitary treatment module 6 positioned on the roof 21 makes it possible to improve the aesthetics of the local urban landscape and to benefit from a functional green area easily accessible to the operators and optionally to the residents, without intruding on building spaces used for other purposes.

[0093] Furthermore, in addition to pre-treatment of wastewater EP, the phyto-purification module 6 on the roof also allows the recycling and treatment of rainwater. The recycling of rainwater is in line with the active, ecologically responsible management of the water available for human use and thus contributes to the conservation of water resources.

[0094] like Figure 3 or Figure 4 As shown, the treatment module 6 comprises at least one saturated / unsaturated flow planted filter 62, allowing biological purification in fine granular media. The operating principle of the planted filter in the module 6 is based on the hydraulic management (filling / emptying) of the basin containing it, causing alternating phases of saturation (anaerobic) and oxygenation (aerobic).

[0095] Planted filter 62 includes a single gravel pack 622 (e.g. Figure 3 and Figure 4The filter comprises at least two gravel packs 622 positioned in parallel and supplied in parallel, all of which are located in a single divided basin, thus forming an integral module 6, or all of which are located in several separate basins, thus forming a modular structure planted filter, which is easy to adapt to different needs. The filtration of the pretreated water EP is performed by (multiple) gravel packs 622. Preferably, the gravel pack or each gravel pack 622 is formed by a filter medium based on inert aggregates of different particle sizes (for example based on charcoal), in which mainly or only halophytes 623 (for example reeds) grow.

[0096] The nature and choice of the filter medium (i.e. the substantially inert aggregate) forming the or each gravel pack 622 and the nature of the plants 623 may be defined by a person skilled in the art according to the amount of water to be treated, the desired filtration capacity and the desired purified water EE quality.

[0097] The principle of phytosanitary water treatment is based on the development of a dense network of halophyte rhizomes that allow providing the gravel pack(s) 622 with a microbial growth medium, aiding the water purification process.

[0098] The presence of the halophytes 623 acts as a mechanical dredging device for the gravel pack surface and promotes the penetration of the pre-treated water EP from the dispersion device 61 into the inert aggregate filter medium. The pre-treated water EP will drain along the roots towards the bottom of the gravel pack 622 in question, while the suspended solids will remain on the surface and then mineralize under aerobic conditions during the bed emptying phase in order to be used as nutrients for the plants.

[0099] Furthermore, in addition to the physicochemical retention of pollutants in the pretreated water EP on the surface of the gravel pack 622 involved, the microbial activity of the rhizomes of the plants 623 enhances water purification.

[0100] Specifically, rhizosphere microorganisms have a biological purification effect, they:

[0101] - consume or at least degrade dissolved organic matter in the pre-treated water EP, and

[0102] - participate in the degradation of nitrogen compounds, phosphates or other trace elements, and likewise in the development mechanisms of plants, and under appropriate circumstances even heavy metals can be converted into less toxic forms.

[0103] Thus, the structure of the phyto-purification treatment module 6 allows the conversion of pre-treated water EP into purified water EE by means of a planted filter 62 having a gravel pack(s) 622 planted with plants 623 .

[0104] According to the invention, in order to ensure the production of purified water EE at the outlet of the plant purification pretreatment module 6, a saturated / unsaturated flow planted filter 62 is selected, which is formed by a single gravel pack 622 planted with plants 623 or at least two hydraulically separated gravel packs 622 planted with plants 623, arranged in parallel (forming two submodules arranged in parallel in structure and function) and operated alternately. Optionally, at least two planted filters 62 (forming two stages of modules 6 arranged in series) can be envisaged as a function of the desired treatment and operation.

[0105] Advantageously, the implementation of the saturated / unsaturated flow planted filter 62 is based on supplying a uniform surface water tank to a gravel pack 622 of a single stage of the planted filter 62 (the planted filter may also include at least two filtration stages in series) or to one or the other of two parallel arranged gravel packs 622 (alternating sequentially).

[0106] Thus, if there are two gravel packs 62, the pretreated water EP arrives alternately on one or the other of the gravel packs 622 via the dispersion device 61. Thus, for a saturated-unsaturated flow planted filter, one of the gravel packs 622 will be in a "rest phase" in which no pretreated water EP is discharged, while the other will be in a "feed phase" in which pretreated water EP is continuously discharged. For a planted filter 6 with a single gravel pack 622, these two phases follow each other sequentially.

[0107] In the gravel pack 622 in the "feed phase", the pre-treated water EP percolates through the aggregate and rhizome filter media for a predetermined residence time, emerging as purified water EE. Simultaneously and in parallel, the other gravel pack 622 is in the "rest phase", i.e. drained, without being fed with pre-treated water EP.

[0108] The "resting phase" of the gravel pack 622 allows the suspended matter accumulated during the previous "feeding phase" to dry and mineralize. The resting phase is necessary to promote the regeneration process of its filtration characteristics by ensuring that aerobic treatment conditions of the gravel pack involved are maintained.

[0109] In the case of a single gravel pack 622, the two phases (feed and rest) must be sequential.

[0110] In the phytosanitary treatment module 6, "rest phases" and "feed phases" with defined "residence times" are important for its proper operation, reliability and life over time and give rise to alternating phases of saturation (anaerobic) and oxygenation (aerobic).

[0111] For the purposes of the present invention, the "residence time" corresponds to the time required to treat the pretreated water EP and convert it into purified water EE, i.e. the time required for the pretreated water EP to come into contact with the gravel pack 622, being a function of the size of the gravel pack and the content of the filter medium (aggregate+plant roots).

[0112] It goes without saying that, although the invention is more particularly directed to a module 6 having a single planted filter 62 , according to other implementation variants (not shown) of the module 6 according to the invention, several planted filters 62 may be operated in parallel or in series.

[0113] According to a first embodiment of the invention represented in the attached drawings, the phyto-purification treatment module (6) comprises a single planted filter (62) comprising a single gravel pack (622) planted with plants (623) and undergoing alternating phases of filling and partial or total emptying.

[0114] According to a second embodiment of the invention (not specifically shown but easily deducible from the accompanying drawings), the plant purification treatment module (6) comprises at least two planted filters (62), which are either arranged in series and thus form two successive filtration stages of the module (6), or are arranged and supplied in parallel, so that the two planted filters (62) undergo successive alternating phases of filling and partial or complete emptying.

[0115] In the above two embodiments, as a variant of the presence of a single gravel filler, the planted filter or each planted filter (62) of the plant purification treatment module (6) may include at least two gravel fillers (622) planted with plants (623), the two gravel fillers being positioned in parallel and supplied in parallel, the gravel fillers (622) being located in a single partition basin, thereby forming a planted filter (62) with a single structure, or the gravel fillers being located in several separate basins, thereby constituting a planted filter (62) with a modular structure, the various gravel fillers being advantageously supplied and drained alternately with each other.

[0116] As an example of a practical implementation of the plant purification module 6, Figure 3 and Figure 4 As shown, the phyto-purification treatment module may include at least one phyto-purification basin with a total height or depth of about 30 cm, which contains a planted filter 62 constituting a biological treatment system. The bottom of the gravel pack 622 of the filter is preferably zero slope.

[0117] The gravel pack 622 (which also forms the growth substrate for the planted plants 623) has a height or depth of about 20 cm and is mixed with small inert supply mineral aggregates. The planted filter 62 is supplied with pre-treated grey water EP via a specific irrigation system (dispersion device 61) supplied by the transfer device 5 over the entire surface area of ​​the planted filter 62. The maximum filling height in this example is 20 cm (maximum water level in the gravel pack). Above this height, an overflow system 63 allows excess water generated by abnormally high supply levels or strong rainfall events to be discharged into the wastewater network (network B).

[0118] The gravel fill 62 is planted with plants 623 belonging to hardy marsh species, called halophytes, selected from, for example, irises, sedges, rushes, loosestrife and meadowsweet. These particular species, which appear mainly with their feet in the water, accept regular changes in the water level.

[0119] The gravel pack 62 is fed intermittently to promote reoxygenation, and the residence time of the water in the gravel pack 62 is advantageously at least 4 hours. The transfer of the purified water EE at the outlet of the gravel pack 62 towards the storage tank 8 by gravity can be controlled, for example, either actively by intermittently opening the controlled discharge ports 7, 71, or passively by a hydraulic device of the "siphon bell" type.

[0120] As a practical example, the gravel pack 62 may comprise aerobic fixed plants 623 on a fine support (e.g. 20 cm of volcanic ash with a particle size of 3 / 6 mm). The flow is of combined type, i.e. vertical (upper part of the gravel pack 62) and horizontal (lower part of the gravel pack 62). The supply with pretreated grey water EP is carried out through successive controlled feed tanks, the emptying being controlled, for example, by means of controlled or program-controlled solenoid valves 71. The alternating function of the filter (especially without supply during the night, combined with saturation phases and draining phases) causes a controlled biomass development of the planted filter 62.

[0121] According to the invention, the dispersing device 61 of the phytopurification pretreatment module 6 diffuses (extensive surface spraying) the pretreated water EP in the "feed phase" onto the gravel packing 622. Advantageously, and in addition to the effect of the alternating feed tanks, the diffusion also contributes to the oxygenation of the filter medium, which promotes the growth of rhizosphere microorganisms in the rhizosphere and helps eliminate pathogenic microorganisms and pollutants from the water.

[0122] According to the invention, the treatment plant 1 comprises means for managing and controlling the supply and diffusion of pre-treated water EP on the gravel pack(s) 622 of the phyto-purification treatment module 6 .

[0123] In order to compensate for the rainy season and the accumulation of rainwater in the gravel pack (s) 622, the phyto-purification treatment module 6 comprises, in addition to the pre-treated water EP, an overflow device 63 which can be Figure 4 Seen in and Figure 5 expressed specifically in.

[0124] This overflow device (63) allows passive management of the amount of water present in the gravel pack (622). Thus, in the event of excessive rainfall (which could hamper the purification process in the phyto-purification treatment module 6, in particular by saturating the gravel pack 622), the overflow device 63 can either store the excess water until the end of the rainy season or discharge it to the external purification system B.

[0125] according to Figure 4 and Figure 5 In the particular embodiment shown, the overflow device 63 is in the form of a hollow, watertight box (or chute) located in the module 6 and forming a retention dam at the outlet of said module 6. The overflow device is equipped with orifices located at one or more predetermined heights and calibrated to regulate the discharge and also to prevent residues (such as leaves, substrate or root fragments in particular) from penetrating into the box.

[0126] According to another possible characteristic of the invention, which is compatible with the previous examples and embodiments, means 7 for collecting and conveying the purified water EE are present at the outlet of at least two gravel packs 622, preferably at the outlet of overflow means 63 that collect the water that has passed through said gravel packs 622. These collecting and conveying means 7 advantageously comprise means 71 for managing the residence time of the pretreated water EP within the phyto-purification treatment module 6.

[0127] For example, according to Figure 4 In the particular embodiment shown, the collection and transport device 7 comprises a trough-shaped collection drain facing downward from the plant purification treatment module 6 , which is optionally connected to a ventilation riser 72 and a solenoid valve 71 which controls the residence time of the pre-treated water EP in the gravel pack 622 .

[0128] Opening the solenoid valve 71 allows the purified water EE produced by the phyto-purification treatment module 6 to be transferred to the tank-type storage device 8. Closing the solenoid valve 71 allows the water to be stored in the phyto-purification treatment module 6 for at least the time required to purify the pre-treated water EP via the gravel pack 622.

[0129] According to a preferred embodiment of the invention, the residence time management device 71 , for example of the solenoid valve type 71 , is combined with a mechanical filtering device, for example of the mesh filter type, in order to avoid discharging the purified water EE comprising solid compounds, in particular originating from the gravel pack 622 , into the storage device 8 .

[0130] like Figure 2 As shown, the storage means 8 comprise a storage tank arranged at the outlet of the phytopurification treatment module 6 and equipped with a microbial disinfection device 9 , allowing the purified water EE leaving the module 6 to be transformed for its intended use into treated water ET complying with the health regulations in force locally.

[0131] According to an example of implementation of the storage device 8 , which is compatible with the above-described examples, the storage device comprises means for managing the amount of water and regulating the water supply.

[0132] For example, the means for managing the amount of water and regulating the water supply comprise a pressure switch intended to manage the supply to the storage device 8 either with purified water EE purified by plants or with water C from the mains supply. In particular, the storage device 8 must comprise a sufficient amount of water to actuate the microbial disinfection device 9 and, therefore, in the event of insufficient water, the pressure switch allows the storage device 8 to be replenished with water C from the public drinking water network, or even with water C from another source (natural or other).

[0133] According to another advantageous feature of the invention (which Figure 2 The microbial disinfection device 9 comprises a device 91 for injecting a disinfectant solution and a device 92 for monitoring the disinfection degree 92 of the purified water EE.

[0134] according to Figure 2 In the particular embodiment shown, the injection means 91 comprise a piston or a pump for injecting a disinfectant solution consisting of hydrogen peroxide, for example in the form of an aqueous hydrogen peroxide solution. The oxygenation of the purified water EE contained in the storage means 8 allows it to be immediately disinfected, thereby providing treated water ET with a microbiological quality that meets the ARS standards for use in toilet flushing systems of buildings 2 or in watering systems for green areas.

[0135] like Figure 2 As shown, according to a particular variant compatible with the preceding example, the means 92 for controlling the disinfection of the treated water EE comprise means for continuous checking of the operating state of the means 91 for injecting a disinfectant solution.

[0136] For example, the means for continuously checking the operating state of the injection device 91 consist of a module for monitoring the amount of disinfectant solution injected into the storage device 8, which module is equipped with means for signaling when the amount of disinfectant solution in the storage device 8 is insufficient.

[0137] The disinfection control device 91 thus adequately treats the purified water EE to obtain treated water ET having a microbiological quality satisfying current standards for reuse in the circuit B1 , for example for supplying water for toilet flushing or for crop irrigation.

[0138] In the treatment facility 1 of the invention, the correct operation (preferably continuous operation) of the microbiological disinfection device 9 ensures the microbiological quality of the treated water ET. The permanent injection of the disinfectant solution into the storage device 8 allows the disinfection and treatment of the purified water EE in order to transform it into the treated water ET. The microbiological quality of the treated water ET is thus ensured by the disinfection control device 92, which constantly monitors and checks the correct operation of the injection device 91 in order to adjust the amount of solution injected in the event of any shortage.

[0139] Thus, according to the invention, the microbiological disinfection device 9 is configured to ensure the microbiological quality of the treated water (ET) for its intended use, according to current health regulatory standards.

[0140] According to a possible optional feature of the treatment plant 1 according to the invention, which is compatible with the above-described example, the discharge and / or recirculation device 10 may comprise means for additionally checking the microbiological quality of the treated water ET.

[0141] The presence of an additional device for checking the microbiological quality of the treated water ET leaving the storage device 8 and circulating in the distribution device 10 is an additional guarantee that the treated water ET complies with the standards or regulations in force in the place where the invention is implemented. In particular, this additional device makes it possible to check whether no microbiological contamination has occurred during the circulation in the distribution device 10.

[0142] For example, the additional means for checking the microbiological quality of the treated water ET consists of at least one device for collecting water samples present on the dispensing device 10. Collecting the sample allows the treated water to be microbiologically analyzed to check whether it actually complies with the standards. Advantageously, the sampling device is positioned upstream of a multi-way valve connected both to the external purification network B and to the B1 circuit supplying water to the toilet flushing or watering devices of the building 2, so as to be able to selectively direct the water to the appropriate network according to the sample result, it goes without saying that if the normative conditions are met, the circuit B1 is preferred.

[0143] If, after taking the water sample, the water quality complies with the current microbiological standards, the water is directed to a circuit B1 which feeds a toilet flushing or watering device in the building 2 via a multi-way valve.

[0144] If, on the other hand, after checking, the quality of the water does not comply with current microbiological standards, for example because contamination has occurred in the dispensing device 10 , the water is directed to an external purification network B via a multi-way valve.

[0145] According to another example of a possible development of the treatment facility 1, which is compatible with the preceding example, the discharge and / or recycling device 10 comprises a network of pipes configured to direct the treated water ET to (multiple) circuits B1 for supplying water for flushing toilets in the building 2 and / or for at least one plant and / or green space watering device located in or around the building 2, and / or to an external purification or sewage network B.

[0146] According to another possible additional characteristic of the invention, the drainage and / or recycling device 10 also comprises additional mechanical filtering means 101 at least upstream of the circuit B1 for supplying water to the local toilet flushing and / or watering devices.

[0147] According to a particular embodiment of the treatment facility 1 , and in particular to ensure personal safety, the additional mechanical filtering means 101 are, for example, in the form of a mesh filter (e.g. 150 micron filtration) and / or a zeolite filter (e.g. 50 micron filtration), such as Figure 2 shown.

[0148] According to the present invention, for use in a toilet flushing supply circuit B1, an additional mechanical filtering device 101 is required to comply with current water quality standards.

[0149] Preferably, additional mechanical filtering means 101 are present at least upstream of said supply circuit B1 for toilet flushing or watering of green areas of building 2 , in order to ensure the quality of the treated water ET intended for this purpose by additional means.

[0150] These additional mechanical filtering devices 101 thus allow a last filtration of the treated water ET, ensuring the safety of the water purification and disinfection operations, so as to ensure its safety of use by guaranteeing its microbiological quality, before transferring it to the supply circuit B1 .

[0151] According to another possible advantageous development of the treatment plant 1 , the pre-treatment module 4 , of which the storage device 42 for waste water (EM) and / or the storage device 8 for purified water (EE) preferably forms a part, comprises at least one overflow discharge system.

[0152] The overflow discharge system allows the excess water to be discharged to the purification network B, thus avoiding saturation or overflow of the storage device 42 or 8 and malfunction of the treatment plant 1 .

[0153] The treatment facility 1 thus allows the conversion of wastewater EM coming from a building into treated water ET of sufficient microbiological quality for use in a circulating supply loop B1 for local installations such as the toilet flushing system in the building 2 in question or for the watering of green areas, with minimal changes to the building's external environment, thus facilitating the adoption of ecologically responsible means to contribute to the reduction of atmospheric pollution in urban environments.

[0154] like Figure 1 Another subject of the invention, schematically shown in , is a building 2 for catering or collective housing, in particular a tertiary or residential building, characterised in that it comprises a facility 1 for treating wastewater EM of the domestic wastewater type, in particular or exclusively, generated by its occupants, as described above.

[0155] It goes without saying that the invention is not limited to the embodiments described and represented in the accompanying drawings. However, modifications are still possible, notably as to the construction of the various elements or by the substitution of technical equivalents, without departing from the field of protection of the invention.

Claims

1. A plant (1) for treating wastewater (EM) from a building (2), characterized in that The facility includes: - means (3) for collecting waste water (EM), - a pretreatment module (4) configured to transform said wastewater (EM) into pretreated water (EP), a phyto-purification treatment module (6) positioned on the roof (21) of the building (2) and configured to transform the pre-treated water (EP) into purified water (EE), - means (8) for storing said purified water (EE), said means advantageously being equipped with a microbiological disinfection device (9) configured to transform said purified water (EE) into treated water (ET), and - means (10) for recycling the purified water (EE) or, where appropriate, the treated water (ET) into at least one internal or local circuit (B1) for reusing the purified water (EE) or treated water (ET) in or around the building (2), and / or for discharging the purified water (EE) or treated water (ET) by default or due to excess into an external purification or sewage network (B), The treatment module (6) comprises at least one saturated / unsaturated flow seeded filter (62).

2. The treatment facility (1) according to claim 1, characterized in that The treatment plant comprises more precisely: - means (3) for collecting waste water (EM), in particular at least domestic waste water (EM), preferably by gravity, configured to feed the pretreatment module (4), - means (5) for transferring the pre-treated water (EP) to the phyto-purification treatment module (6), these transfer means (5) advantageously comprising at least one self-cleaning lifting pump (51) combined with a lifting column (52), - means (7) for collecting the purified water (EE) and conveying it to the storage device (8), the storage device being equipped with a microbiological disinfection device (9) for converting the purified water (EE) into treated water (ET), - means (10) for recycling the treated water (ET) into at least one circuit (B1) for supplying water to at least one device for flushing toilets in the building (2) and / or for watering or irrigating crops, such as plants, window boxes and / or cultivated green areas or landscaping areas located in or around the building (2), and / or for discharging the treated water (ET) into the external purification or sewage network (B).

3. The treatment facility (1) according to claim 2, characterized in that The lifting column (52) is configured and dimensioned to generate a venturi effect during transfer of the pre-treated water (EP) to the phyto-purification treatment module (6), thereby oxygenating the pre-treated water (EP) within the lifting column (52).

4. The treatment facility (1) according to any one of claims 1 to 3, characterized in that The pre-treatment module (4) is located in the lower part or cellar of the building (2), for example in a technical room (1') in the basement together with the storage tank (8) and possibly at least part of its ancillary equipment, and comprises: - at least one separation device (41) configured to separate waste water (EM) from solid waste, in particular food or organic waste, and, - at least one device (42) for storing waste water (EM), optionally equipped with mechanical filtering means (43), the discharge of which is preferably directed by gravity to the transfer device (5).

5. Treatment plant (1) according to the preceding claim, characterized in that The separation device (41) comprises at least one self-cleaning separation filter, for example of the vortex type.

6. The treatment facility (1) according to any one of claims 1 to 5, characterized in that The treatment plant comprises means (61) for dispersion and surface distribution of the pre-treated water (EP) at the level of the phyto-purification treatment module (6).

7. The treatment facility (1) according to any one of claims 1 to 6, characterized in that The feeding of the planted filter(s) (62) with a combined [vertical+horizontal] flow is performed by means of dispersion and surface distribution means (61), the treatment module (6) also comprising overflow means (63).

8. The treatment facility (1) according to any one of claims 1 to 7, characterized in that The device (5) for transferring pretreated water (EP) to the phyto-purification treatment module (6) is configured and controlled to carry out the supply of the water tank to the (multiple) planted filters (62), and the device (7) for collecting the purified water (EE) and conveying it to the storage device (8) is configured and controlled to carry out partial or complete emptying of the purified water (EE) from the (multiple) planted filters (62) in a controlled manner or at regular intervals corresponding to a preprogrammed residence time, thereby causing alternating phases of filling and emptying of the phyto-purification treatment module (6).

9. The treatment facility (1) according to any one of claims 1 to 8, characterized in that The phyto-purification treatment module (6) comprises a single planted filter (62) comprising a single gravel pack (622) planted with plants (623) and undergoing alternating phases of filling and partial or complete emptying.

10. The treatment facility (1) according to any one of claims 1 to 8, characterized in that The phytosanitary treatment module (6) comprises at least two planted filters (62) which are either arranged in series and thus form two successive filtration stages of the module (6) or are arranged and supplied in parallel and then undergo successive alternating phases of filling and partial or complete emptying.

11. The treatment facility (1) according to any one of claims 1 to 10, characterized in that The planted filter or each planted filter (62) of the plant purification module (6) includes at least two gravel packings (622) planted with plants (623), which are positioned in parallel and supplied in parallel. These gravel packings (622) are located in a single partition basin, thereby forming a planted filter (62) with a single structure, or these gravel packings are located in several separate basins, thereby forming a planted filter (62) with a modular structure, and various gravel packings are advantageously supplied and drained alternately.

12. The treatment facility (1) according to any one of claims 1 to 11, characterized in that The or each gravel pack (622) comprises a plant growth substrate (623) of an inert small-sized mineral aggregate type, for example a 20 cm layer of volcanic ash or charcoal with a particle size of 3 / 6 mm, and is planted with plants (623) belonging to hardy marsh species known as halophytic macrophytes, for example selected from iris, carex, bulrushes, purple loosestrife, and meadowsweet.

13. Treatment plant (1) according to at least one of claims 2 to 12, characterized in that The device (7) for collecting and conveying purified water (EE) present at the outlet of the at least two gravel packs (622) comprises means (71) for managing the residence time of the pre-treated water (EP) in the planted filter(s) (62) of the phyto-purification treatment module (6).

14. The treatment facility (1) according to any one of claims 1 to 13, characterized in that The storage device (8) includes means for managing the amount of water and regulating the water supply.

15. The treatment facility (1) according to any one of claims 1 to 14, characterized in that The microbial disinfection device (9) comprises a device (91) for injecting a disinfectant solution and a device (92) for monitoring the degree of disinfection (92) of the purified water (EE).

16. Treatment plant (1) according to the preceding claim, characterized in that The device (92) for monitoring the disinfection of the purified water (EE) comprises means for continuously checking the operating state of the device (91) for injecting a disinfectant solution.

17. The treatment facility (1) according to any one of claims 1 to 16, characterized in that The microbiological disinfection device (9) is configured to ensure the microbiological quality of the treated water (ET) for its intended use, according to current health regulatory standards.

18. The treatment facility (1) according to any one of claims 1 to 17, characterized in that The discharge and / or recirculation device (10) comprises means for additionally checking the microbiological quality of the treated water (ET).

19. The treatment facility (1) according to any one of claims 1 to 18, characterized in that The discharge and / or recycling device (10) comprises a pipe network configured to direct the treated water (ET) to (multiple) circuits (B1) for supplying water for flushing toilets of the building (2) and / or at least one plant and / or green space watering device located in or around the building (2), and / or to the external purification or sewage network (B).

20. The treatment facility (1) according to any one of claims 1 to 19, characterized in that The drainage and / or recycling device (10) also comprises additional mechanical filtering means (101) in the form of a sieve filter and / or a zeolite filter upstream of said at least one circuit (B1) for supplying water to the local toilet flushing and / or watering device.

21. The treatment facility (1) according to any one of claims 1 to 20, characterized in that The pre-treatment module (4) comprises at least one overflow discharge system leading to the purification network (B), the storage device (42) for waste water (EM) and / or the storage device (8) for purified water (EP) forming a preferred part of the pre-treatment module.

22. The treatment facility (1) according to any one of claims 1 to 21, characterized in that Only the plant purification module (6) is installed on the roof (21) of the building (2), the pretreatment module (4) and its buffer storage tank (42) for wastewater (EM) and the storage tank (8) for purified water (EP) as well as possible other components of the facility (1) are arranged in a technical room or the like (1') in the basement of the building (2).

23. A building (2) for catering or collective housing, especially a tertiary industry or residential building, characterized in that: The building comprises a plant (1) as claimed in any one of claims 1 to 22 for treating waste water (EM), in particular or exclusively domestic waste water type, generated by its occupants.

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