Wastewater treatment system and installation

Abstract

Device and installation for the treatment of domestic, agricultural and / or industrial wastewater, configured for installation at least partially underground, the device comprising an aerobic reactor (10) comprising a series of essentially horizontal tubes (131-136), each of the tubes in the series of tubes (131-136) being in fluidic connection upstream with a distribution chamber (120) and downstream with a ventilation chamber (140), the distribution chamber (120) and the ventilation chamber (140) being provided with passive aeration chimneys (121, 141) of the aerobic reactor (10), the tubes (131-136) of the aerobic reactor being made of porous cellular concrete, the porosity coefficient of which is a minimum of 35%, these cellular concrete tubes being configured to allow both the progressive transit by percolation of wastewater through the material, the installation of purifying biomass and aeration by passive ventilation. (Fig. 1)

Description

Title of the invention: Wastewater treatment device and installation technical field

[0001] The present invention relates to the treatment (purification) of wastewater and more particularly to wastewater treatment devices in the fields of domestic, agricultural and / or industrial wastewater, as well as the installation of such devices. State of the art

[0002] The treatment of domestic, agricultural, and / or industrial wastewater is widely developed for all kinds of microbiological applications, particularly according to the processes known as "activated sludge", "fixed culture" or "filtration".

[0003] Individual wastewater treatment can be carried out, depending on the process chosen, by small treatment plants (micro-stations) comprising several compartments. The water passes successively through the different compartments, each integrating different and / or specific functions, such as, for example, grease removal, sedimentation of solid particles, biological degradation by bacterial digestion, etc.

[0004] Depending on the daily hydraulic load to be treated, these different compartments are either integrated into a single tank (micro station), or into multiple tanks.

[0005] Depending on the desired level of sanitation, microbiological degradation will require a greater or lesser supply of oxygen. This supply can be achieved through forced or natural oxygenation, depending on the systems used. The main advantage of oxygenation by natural ventilation is that it does not consume energy (passive purification) and therefore does not require specific electromechanical equipment and its associated wear and maintenance.

[0006] In the category of devices by "filtering" commonly called "passive" it is generally necessary to note the fact of the absence of energy for the proper functioning of the devices, therefore absence of electromechanical equipment.

[0007] Beyond wastewater treatment, the question of the disposal of treated (purified) water always arises. The primary and generally regulatory solution for small installations will be to percolate the treated water by drainage on the land parcel, thus allowing the replenishment of underground groundwater.

[0008] In individual sanitation systems, the discharge of treated wastewater into a surface network is generally impractical because the land area in question does not have a suitable outlet (stream, river, pond, etc.) or is undersized. Object of the invention

[0009] An object of the present invention is therefore to propose an efficient, simple, reliable and long-lasting wastewater treatment device, which does not consume energy during normal operation, which can be installed underground and requires little control or maintenance. General description of the invention

[0010] In order to solve the problem mentioned above, the present invention proposes, in a first aspect, a device for the treatment of domestic, agricultural and / or industrial wastewater, configured for installation at least partially underground (below ground level). The device comprises an aerobic reactor including a series or plurality of essentially horizontal tubes, each of the tubes in the series being in fluidic connection upstream with a distribution chamber and downstream with a ventilation chamber.The distribution chamber and the ventilation chamber are equipped with passive aeration chimneys for the aerobic reactor, and the tubes of the aerobic reactor are made predominantly and mainly of porous cellular concrete (i.e., at least in their lower and lateral parts), with a porosity coefficient of at least 35%. These cellular concrete tubes are configured to allow both the progressive percolation of wastewater through the material, the installation of purifying biomass, and aeration by passive ventilation.

[0011] In a second aspect, the invention relates to a domestic, agricultural and / or industrial wastewater treatment plant, comprising a treatment device according to the first aspect, each tube in the series of tubes, the distribution chamber and the ventilation chamber of the aerobic reactor being installed below ground level (underground), so that only the upper parts of the passive ventilation stacks of the aerobic reactor are above ground level.

[0012] During normal operation, the tubes will be partially filled with the wastewater to be treated (called the hydraulic section), while the remaining cross-section of the tubes (i.e., the upper part of the essentially horizontal tubes) will be used for air circulation (called the ventilated section), supplying the biomass with the oxygen necessary for purification. The internal cross-section of each tube is therefore chosen to be sufficiently large; generally, it will be at least 300 cm². The internal cross-section of each tube can be of any shape, preferably circular, oval, or polygonal, and particularly preferably circular, square, or rectangular. Advantageously, the tubes have a square or rectangular internal cross-section. They can advantageously be formed in two parts, the inner part The lower section forms a channel, and the upper section forms a lid. In these variations, the upper section formed by the lid does not necessarily have to be made of cellular concrete, since percolation occurs primarily by gravity and capillary action through the lower and lateral parts of the hydraulic section—that is, in this case, through the walls of the channel, which is made of porous cellular concrete. The lid can therefore be made of conventional concrete, reinforced or unreinforced.

[0013] The sizing of the aerobic reactor, in this case the length and number of tubes, is generally a function of the daily hydraulic load on the one hand and of the soil's capacity to percolate this hydraulic load on the other hand, when the size of the tube cross-section has been fixed.

[0014] The connection between the tubes, the distribution chamber and the ventilation chamber is made in any appropriate way, preferably either by plugging, or by sleeving, or by butting, or by gluing, or by a combination of two or more of these methods of connection.

[0015] The tubes are arranged essentially horizontally, that is to say that the slope with respect to the horizontal of the series of tubes between the distribution chamber and the ventilation chamber is less than + / - 5%, preferably less than + / - 2%.

[0016] As already mentioned above, it is noteworthy that the water purification occurs through percolation via the walls of the porous cellular concrete tubes, which simultaneously serve as a support for the biomass performing this aerobic purification. The tubes therefore do not have (added) perforations to perform this function. Indeed, creating perforations in the wall would cause the water to drain too quickly, thus percolating untreated water into the natural ground and therefore into the water table. In practice, the tubes do not have perforations in the walls (of the hydraulic section).

[0017] As an exception, in order to cope with an accidental or exceptional hydraulic overload exceeding the nominal or regulatory hydraulic load, each tube may advantageously be provided with perforations at the top of the tube cross-section, acting as an overflow outlet. These overflow outlet perforations are therefore located in the ventilated section, or even at the top of this ventilated section, which does not contain water during normal operation. The diameter of these perforations is generally at least 15 mm. Preferably, these perforations are provided at regular intervals, for example, at least 20 cm apart.

[0018] Often the wastewater treatment system will also include, upstream of the aerobic reactor's distribution chamber, a septic tank for pretreating the wastewater before it is conveyed to the aerobic reactor. The septic tank The wastewater system is then connected upstream to a wastewater inlet and downstream to a supply of water to the distribution chamber to be treated, thus connecting it to the distribution chamber of the aerobic reactor. If necessary or useful, the septic tank is itself equipped with a conventional pre-filter at its outlet.

[0019] In the wastewater treatment system according to the second aspect of the invention, the porous cellular concrete pipes are generally placed on or in a bed of aggregates, the aggregates preferably being sand, in particular washed sand.

[0020] In preferred embodiments of the drainage system or installation, the porous cellular concrete pipes are covered with topsoil. A geotextile is preferably placed between the porous cellular concrete pipes and the topsoil, i.e., at the level of the upper generatrix of the pipes. Alternatively, or in addition, some preferred embodiments provide for a protective geotextile surrounding each porous cellular concrete pipe of the drainage system. These embodiments can be particularly useful during periods of rainfall to prevent sand from entering the porous cellular concrete pipes from the outside in, when the drainage system is not being supplied with water (empty pipes during holidays, absence of users, etc.).For the previously mentioned two-part square internal section tube variants, where the lower part forms a channel and the upper part a cover, the protective geotextile may only cover the channel section if the cover is made of conventional concrete. Ideally, the protective geotextile will therefore cover at least the sections of the tubes made of porous cellular concrete.

[0021] In certain advantageous embodiments, the wastewater treatment system preferably further comprises one or more collection pipes (for example, conventional drainage pipes) arranged below one or more of the porous cellular concrete pipes of the aerobic reactor, the collection pipe(s) being in fluidic connection with a pumping and sampling chamber, accessible from the outside via a pumping and sampling well. Where appropriate, the collection pipe(s) are arranged below the lower level of the aggregate bed.

[0022] In order to improve the collection of treated water for pumping or sampling purposes, the wastewater treatment plant may further include a collection geotextile placed below the collection tube(s) which slows down the percolation of treated water from the aerobic reactor and thus facilitates the penetration of some of this treated water into the collection tubes and flows towards the pumping and sampling well.

[0023] In order to achieve the objectives developed above, the present invention therefore proposes, on the one hand, a sanitation device combining both the treatment equipment and the dispersion equipment, the two being inseparable from each other by in relation to others and on the other hand a corresponding sanitation installation.

[0024] The component of the wastewater treatment system of the invention consists of porous cellular concrete tubes with a porosity coefficient of at least 35%, allowing both the percolation of water through the material and the establishment of purifying biomass (bacteria). Porosity is the total number of voids (pores) in a solid material, which are filled by fluids (liquid or gas). It is a physical quantity between 0 and 1 (or, as a percentage, between 0 and 100%), which determines the flow and retention capacities of a substrate.

[0025] Porosity is also a numerical value defined as the ratio between the volume of voids and the total volume of a porous medium:

[0026] [Math.l] Spores

[0027] where:

[0028] (p is the porosity,

[0029] Vpores the volume of the pores,

[0030] and Vtotal the total volume of the material, that is to say the sum of the volume of solid and the volume of pores.

[0031] The porosity, or porosity coefficient, can be determined by the water saturation method: pore volume = total water volume - water volume remaining after soaking.

[0032] The porous cellular concrete tubes of the present invention can be equipped with or without reinforcements, steel or synthetic fibers.

[0033] The length of a tube will be indifferent but generally adapted to the transport and handling conditions.

[0034] The length of the entire porous cellular concrete tube system will be determined by the daily hydraulic load on the one hand and the soil's capacity to absorb this hydraulic load on the other. This is generally calculated based on the number of inhabitants of the building concerned, and / or the habitable capacity of the building concerned, and / or the consumption ratio per inhabitant according to the relevant national or regional regulations (daily hydraulic load / inhabitant).

[0035] The soil's absorption capacity is determined by the percolation coefficient measured according to the scientific method known as the "Porchet" test (percolation coefficient = coefficient K), which is widely known and commonly used elsewhere. The "Porchet" test of water infiltration into the soil consists of digging a hole in the soil and then saturating it with water for a certain time. The water level is then maintained A constant flow of water is maintained in this hole (while continuing to pour water into it), and the volume of water that infiltrates the soil is measured over a certain period. This test is a standardized test used to assess the suitability of soil for on-site wastewater treatment.

[0036] The number of tubes composing an installation will depend on the production length of the tubes, the coefficient K, the hydraulic load retained and the importance of the overall installation sizing.

[0037] The internal diameter or cross-section of each tube composing the device shall be a minimum of 300 square centimeters (cm2).

[0038] The connection between tubes is made indifferently either by insertion or by sleeve, either butted together, or by gluing.

[0039] In order to ensure good oxygenation of the water to be treated and thus supply oxygen to the bacteria composing the treatment biomass, the present invention provides an air intake chimney upstream and an air intake chimney downstream of the tubes of the sanitation device in order to create a permanent airflow through all the porous alveolar concrete tubes of the aerobic reactor.

[0040] As previously stated, in order to cope with an accidental or exceptional hydraulic overload exceeding the nominal capacity or, where applicable, exceeding the loads stipulated by various regulations, porous cellular concrete pipes are preferably equipped every 20 cm with perforations of at least 15 mm in diameter in the concrete mass at the level of the upper generatrix, thus acting as an overflow outlet where necessary. The configuration of a square or rectangular pipe with a traditional concrete upper generatrix is ​​exempt from this specific provision.

[0041] Each tube may indifferently be of circular, square or rectangular shape, random, chamfered or joined, in simple and / or multiple structures.

[0042] The arrangement of the porous cellular concrete tubes in space will be carried out taking into account the topography of the plot of land on which the device will be installed.

[0043] The porous cellular concrete tubes of the aerobic reactor are advantageously installed in a bed of granular solid material or aggregates, for example sand, gravel and / or crushed stone, in this case washed sand, with a height corresponding to the cross-section of the tubes plus a minimum of 30 cm placed below the tubes. Generally, a washed, water-stable, siliceous rounded sand derived from alluvial materials will be used.

[0044] With the general exception of the square or rectangular tube version with a standard concrete top profile, porous cellular concrete treatment tubes shall be covered with a raised geotextile (uplift height h, preferably of about 10 cm) on the side of the trench to prevent clogging by soil intrusion. However, it may be advantageous to provide a geotextile surrounding each porous cellular concrete pipe of the sanitation system to prevent, during rainy periods, sand intrusion from the outside to the inside of the pipes, when the sanitation system is not supplied (empty pipes during holiday periods, absence of users, etc.).

[0045] The square or rectangular tube version is generally preferred for greater production cost savings, offering the possibility of a two-piece construction, with the upper section or cover being made of traditional, non-porous concrete. The upper section is preferably installed without joints or adhesives, thus allowing for the drainage of any hydraulic excess. This design also facilitates transport, storage, and installation, as well as the irrigation of vegetation where applicable.

[0046] For information purposes, it is noted that the construction details of a particularly preferred variant of the sanitation system will be equipped as follows:

[0047] Upstream of the aerobic reactor, a standard all-water septic tank (AWT) with a pre-filter is preferably installed, collecting both wastewater from kitchens, bathrooms, etc. (greywater) and wastewater from human metabolism (blackwater). It performs the classic functions of primary settling and pretreatment.

[0048] The sizing of the standard FTE will be carried out taking into account the daily hydraulic load to be treated in accordance with the regulatory provisions in force in this area.

[0049] The aerobic reactor includes a ventilated distribution chamber contributing to the oxygenation of the biomass contained in the porous cellular concrete treatment tubes, the distribution chamber being placed downstream of the FTE and upstream of all the porous cellular concrete tubes.

[0050] Downstream of the porous concrete tubes is a ventilation chamber which provides both the ventilation air intake for all the porous cellular concrete tubes, the purge point and the control point of the device. Characteristics of the invention

[0051] The originality of the invention lies in the following points: • A completely passive device requiring no energy • Device requiring no moving mechanical parts • Device exploiting the specific characteristics of porous cellular concrete • Device composed exclusively of durable materials • Device requiring no factory pre-installation • Device designed to be assembled and installed directly on site • “High inlet - high outlet” system requiring no trench deep • Device that does not require specialized equipment for its implementation • Device that does not require specialized equipment or additives for the biomass development • A system that does not require specialized personnel for its implementation • Device requiring no maintenance other than traditional draining / cleaning • Device requiring no parts replacement during maintenance • Device requiring no monitoring other than the calendar emptying of the septic tank (FTE) • Device requiring no specific action to be taken during continuous or intermittent use or after a prolonged absence • Device preventing any risk of olfactory nuisance • A system that percolates treated water onto the land parcel, thus allowing the replenishment of underground groundwater. • A system that percolates treated water onto the land parcel, thus avoiding any risk associated with surface discharges of treated water • Device allowing, where applicable, irrigation of vegetation on the land parcel • Device with an optimal environmental aspect Brief description of the drawings

[0052] Other features and characteristics of the invention will become apparent from the detailed description of some advantageous embodiments presented below by way of illustration, with reference to the accompanying drawings. These show:

[0053] [Fig-1]: is a schematic top view of a first embodiment of a sanitation device according to the first aspect of the invention;

[0054] [Fig.2]: is a schematic top view of a second embodiment of a sanitation device according to the first aspect of the invention;

[0055] [Fig.3A]: is a schematic cross-sectional view of an embodiment of a sanitation installation according to the second aspect of the invention installed below ground level;

[0056] [Fig.3B]: is a schematic cross-sectional view of an embodiment of a sanitation installation according to the second aspect of the invention installed below ground level, further comprising means allowing sampling or lifting of treated water;

[0057] [Fig.4A]: is a cross-section of an advantageous variant of a detail of an embodiment according to the first aspect in which the cellular concrete tubes porous materials are surrounded by a protective geotextile;

[0058] [Fig.4B]: is an advantageous variant of [Fig.4A];

[0059] [Fig. 5A]: is a cross-section of a detail of an embodiment according to the second aspect, showing a variant of an aerobic reactor with tubes of circular cross-section;

[0060] [Fig.5B]: is a cross-section of a detail of another embodiment according to the second aspect, showing a variant of an aerobic reactor with square section tubes;

[0061] [Fig. 6] A to I: A: photograph of a porous cellular concrete, B: cross-section through a tube of circular section, C: tube element with polygonal cross-section (here with several tubes assembled), D: tube elements with rectangular external cross-section (here with several internal tubes with circular internal cross-section), E: schematic top view of several tube elements with circular cross-section, F: tube element with circular cross-section, G: tube element with square external cross-section, H: tube element with square external cross-section in two parts (channel and porous concrete cover) and I: tube element with square external cross-section in two parts (porous concrete channel and traditional concrete cover). Description of preferred executions

[0062] The present invention relates in particular to a passive sanitation device (by "passive" means a device without energy consumption in the context of standard operation) for domestic, agricultural and / or industrial wastewater, without the addition of enzymes or other additives of any kind.

[0063] An advantageous embodiment of the invention includes a series of porous and durable cellular concrete tubes allowing percolation of the water to be treated through the porosities colonized by biomass (bacteria) which will naturally settle there and ensure the digestion of the chemical and organic polluting loads of the wastewater. • The organization of the system allows for optimization: • The ventilation of the device • The natural absorption of O2 in the water to be purified • Bringing the bacteria into contact with O2-rich water allows them to absorb and consume the oxygen necessary for their ability to digest the pollutants present in the water being treated. • Perfect distribution of hydraulic loads across the different treatment tube lines that make up the system • A perfect balance of all parameters: wastewater / surface / biomass / oxygenation / percolation • The durability of the device through the exclusive use of inert, non-toxic materials biodegradable and mechanically self-resistant • The durability of the device through the absence of mechanical or electromechanical components

[0064] An advantageous embodiment of the invention comprises a series of square or rectangular porous and durable cellular concrete tubes for greater production efficiency, offering the possibility of a two-piece construction, the upper section being advantageously made of conventional, non-porous concrete. The upper section is preferably placed without joints or adhesives, thus allowing for the evacuation of any hydraulic excess. This arrangement also facilitates transport, storage, and installation, as well as the irrigation of vegetation where applicable.

[0065] In order to achieve the desired treatment performance, the device takes into account and integrates the sizing parameters necessary for treatment engineering, such as: • The standardized hydraulic load • The different types of standardized organic and chemical pollutants • Loads of sedimentable materials • Suspended solids loads • The rate of biodegradability • The degree of biodegradability • The retention time of wastewater throughout the entire system • The time required for O2 transfer for biomass oxygenation • Standardized hydraulic load variations • Normalized variations in pollutant loads • Where applicable, regulatory discharge standards

[0066] General principles of an advantageous embodiment:

[0067] Percolation sanitation generally proceeds in two phases

[0068] Phase 1

[0069] The pretreatment carried out by a conventional all-water septic tank (AWT) with a pre-filter which performs the functions of • Settling of solid matter and storage of the sludge thus collected • Degreasing by flotation of fats and materials of high density lower than those of water (soaps - shampoos - etc.) and storage of the sludge thus collected • Predigestion of decanted water through the natural development of anaerobic bacteria • Pre-filtration to ensure the quality of sediment retention mentables and suspended

[0070] Phase 2

[0071] The aerobic treatment itself, which is the subject of the present invention and which performs the functions of • Digestion of organic pollutant loads down to the minimum discharge standards prescribed where applicable • Digestion of chemical pollutant loads down to the minimum discharge standards prescribed where applicable

[0072] Phase 2 of the device of the present invention is ensured by the set of porous cellular concrete treatment tubes installed according to the construction arrangements of the present invention. It comprises as main components: the series of porous cellular concrete treatment tubes, generally installed in an underlying layer of filter sand.

[0073] Features of the invention

[0074] The multiple features of the invention and its advantageous embodiments lie particularly in the following points: • The device is equipped with porous cellular concrete structures that provide support for bacteria, allowing the spontaneous development of biomass that colonizes the percolation spaces. • The device is equipped exclusively with porous, inert, stable and durable cellular concrete structures. • The device is equipped exclusively with porous cellular concrete structures in tubular, circular or non-circular shapes • The device is equipped exclusively with porous cellular concrete structures of tubular, circular or non-circular shapes, mechanically resistant, reinforced or not with metallic fibers, synthetic fibers or rebar. • The materials that make up the tubes advantageously have a porous, honeycomb structure calculated to allow percolation through the biomass that has naturally settled within them.

[0075] The specific architecture of the invention provides the following specific features and advantages: • A completely passive device requiring no energy • Device requiring no moving mechanical parts • Device exploiting the specific characteristics of porous cellular concrete • Device composed exclusively of durable materials • Device requiring no factory pre-installation • Device designed to be assembled and installed directly on site • “High inlet - high outlet” system requiring no trench deep • Device that does not require specialized equipment for its implementation • Device that does not require specialized equipment or additives for the biomass development • A system that does not require specialized personnel for its implementation • Device requiring no maintenance other than traditional draining / cleaning • Device requiring no parts replacement during maintenance • Device requiring no monitoring other than the calendar oil changes • Device requiring no specific action to be taken during continuous or intermittent use or after a prolonged absence • Device preventing any risk of olfactory nuisance • A system that percolates treated water onto the land parcel, thus allowing the replenishment of underground groundwater. • A system that percolates treated water onto the land parcel, thus avoiding any risk associated with surface runoff of treated water. • Device allowing, where applicable, irrigation of vegetation on the land parcel • Device with an optimal environmental aspect • Device allowing for dispersion • either by percolation to the plot • either by underground irrigation • either by discharge into the surface water environment

[0076] Figure 1 is a schematic top view of a first embodiment of a wastewater treatment system according to the first aspect of the invention, comprising an aerobic reactor 10 which includes a series of essentially horizontal tubes 131-136 (the number of tubes varies according to the treatment requirements) connected upstream to a distribution chamber 120 and downstream to a ventilation chamber 140. In operation, the wastewater to be treated enters the distribution chamber 120 through the inlet 115, also called the water supply to the distribution chamber, and is then distributed into the various tubes 131-136. In these tubes 131-136, the porous cellular concrete serves on the one hand as a support for the biomass (bacteria) and on the other hand to control the percolation rate of the wastewater through the concrete to allow the biomass to treat the wastewater before its release into the subsoil.Oxygenation of the device is ensured by natural ventilation through the tubes (whose cross-section is only partially filled with water, except in case of overload). exceptional hydraulics) and the ventilation chimneys 121 and 141 of the distribution chamber 120 and the ventilation chamber 140.

[0077] References identical to those in [Fig. 1] or 2 in the other figures designate identical or corresponding elements.

[0078] Figure 2 shows a second embodiment of a wastewater treatment system according to the first aspect of the invention, which further comprises a pretreatment device upstream of the inlet 115 of the aerobic reactor, in particular, for example, a septic tank 210, optionally equipped with a ventilation shaft or an access point 121. In this case, the wastewater to be treated first enters the septic tank 210 through the wastewater inlet 205 and is there separated from its solid matter, degreased from its fats and matter with a density lower than that of water, and then predigested by the natural development of anaerobic bacteria. Preferably, before the water is admitted to the feed 115 of the aerobic reactor 10, the pretreated water is pre-filtered to ensure the quality of the retention of settleable and suspended solids.

[0079] Figure 3A schematically shows, in cross-section, an embodiment of a wastewater treatment plant according to the second aspect of the invention, installed below ground level using a wastewater treatment device embodiment similar to that of Figure 2. The entire aerobic reactor 10, with the exception of the upper parts of the ventilation stacks 121 and 141, is installed below ground level 300 by prior excavation of the natural ground 330 and is, for example, covered with topsoil 320. The porous cellular concrete tubes 131-136 are preferably installed on or in a bed of granular material or aggregates 310, such as sand. The arrows indicate the direction of percolation of the treated water into the natural ground 330.

[0080] Figure 3B schematically shows, in cross-section, an embodiment of a wastewater treatment plant similar to that of Figure 3A, but which also includes means for sampling or pumping treated wastewater, for example, to determine the treatment performance of the plant or to determine whether the treated wastewater at the plant outlet meets the standards. A pumping and sampling chamber 360 is provided below the lower level of the porous cellular concrete pipes 131-136 and, where applicable, below the aggregate bed 310. This pumping and sampling chamber 360 is supplied by one or more collection pipes 350 arranged below one, several, or all of the pipes 131-136 configured to collect a portion of the treated wastewater from the treatment plant.Access to the pumping and sampling chamber 360 is generally provided by a pumping and sampling well 370. In order to . To improve the collection of water to be treated, the installation may also include a 340 collection geotextile placed below the 350 collection tube(s).

[0081] Figures 4A and 4B schematically present cross-sections of two embodiments of the tubes 131-136 of the aerobic reactor, Figure 4A showing a variant with tubes of closed circular cross-section and Figure 4B showing a variant with two-part tubes, i.e. with channel 620 and cover 630. These figures also show the ventilated section 410 and the hydraulic section 420, the water from the hydraulic section percolating through the porous walls colonized by the biomass which progressively purifies the water and the purified water 400 then percolates into the natural ground, possibly passing through a bed of aggregates, as shown in Figures 5A and 5B.

[0082] In these two variants, the tubes, or at least their porous cellular concrete parts, are covered with a protective geotextile 430 which prevents the penetration of sand or soil into the cellular concrete tubes, particularly in rainy periods when the tubes are not supplied (i.e., empty) due to the absence of the inhabitants (second homes, holidays, etc.).

[0083] Figure 5A is a cross-sectional view of a detail of an embodiment according to the second aspect, showing a variant of an aerobic reactor with tubes of circular cross-section. A trench with trench edges 520 is cut into the natural ground 330, and a bed of aggregates 310 is formed at the bottom of the trench before the tubes 131-136 are placed there. The bed is then filled to the height of the top of the tubes. Generally, the bed of aggregates 310 is then covered with a geotextile 510, and then with topsoil 400, the edges of the geotextile 510 preferably being raised to a height h, for example 10 cm, to prevent the topsoil from clogging the bed of aggregates 310 too quickly.

[0084] Figure 5B illustrates a detail of another embodiment according to the second aspect, showing a variant of an aerobic reactor with square-section tubes 131-136, with or without a channel and cover. This variant does not include a geotextile, and the installation is covered by vegetation 500.

[0085] Finally, [Fig. 6] A to I: A: photograph of porous cellular concrete, B: cross-section through a circular tube 131 with a perforation 610 as an overflow in case of exceptional overload, C: polygonal tube element (here with several tubes 131, 132, 133 assembled) also equipped with overflow perforations 610, D: rectangular external tube elements (here with several circular internal tubes), E: schematic top view of several circular tube elements, F: circular tube element, G: one-piece square external tube element 131, H: two-part square external tube element, the channel 620 and cover 630 being in porous concrete and I: two-part square external section tube element, channel 620 being porous concrete and cover 630 being traditional concrete.

[0086] Legend: 10 Aerobic reactor 115 Supply of treated water to the distribution chamber 120 Distribution chamber 121 (First) Ventilation stack 131-136 Series of tubes 140 Ventilation chamber 141 (Second) Ventilation stack 205 Wastewater inlet 210 All-water septic tank (AWT) 211 (Third) Ventilation stack 300 Ground level 310 Aggregates 320 Topsoil 330 Natural ground 340 Collection geotextile 350 Collection pipe 360 ​​Pumping and sampling chamber 370 Pumping and sampling well 400 Treated water percolation 410 Ventilated section 420 Hydraulic section 430 Protective geotextile 440 Overflow outlet 500 Vegetation 510 Geotextile h Lift height (from geotextile) 520 Trench edges 610 Perforation 620 Channel (in porous cellular concrete) 630 Cover (in porous cellular concrete or traditional concrete)

Claims

Claims

1. Device for treating domestic, agricultural and / or industrial wastewater, configured for installation at least partially underground, the device comprising an aerobic reactor (10) comprising a series of essentially horizontal tubes (131-136), each of the tubes of the series of tubes (131-136) being in fluidic connection upstream with a distribution chamber (120) and downstream with a ventilation chamber (140), the distribution chamber (120) and the ventilation chamber (140) being provided with passive ventilation chimneys (121, 141) of the aerobic reactor (10), the tubes (131-136) of the aerobic reactor being made of porous cellular concrete, the porosity coefficient of which is at least 35%, these cellular concrete tubes being configured to allow both the progressive transit by percolation of the wastewater through the material, the installation of purifying biomass and ventilation by passive ventilation.

2. Sanitation device according to claim 1, wherein the internal section of each tube (131-136) is at least 300 cm2.

3. A sanitation device according to claim 1 or 2, wherein the internal section of each tube (131-136) is circular, oval or polygonal, preferably circular, square or rectangular.

4. Sanitation device according to one of the preceding claims, in which a protective geotextile (430) peripherally surrounds each porous cellular concrete tube (131-136).

5. Sanitation device according to one of the preceding claims, in which the tubes (131-136) have a square or rectangular internal section and are formed in two parts, the lower part forming a channel (620) and the upper generatrix forming a cover (630).

6. Sanitation device according to one of the preceding claims, in which the length and the number of tubes is a function of the daily hydraulic load on the one hand and the capacity of the soil to percolate this hydraulic load on the other hand.

7. Sanitation device according to one of the preceding claims, in which the connection between tubes (131-136), distribution chamber (120) and ventilation chamber (140) is made either by fitting, or by sleeving, or by joining, or by gluing.

8. Sanitation device according to one of the preceding claims, in which each tube is provided with perforations (610) of diameter of at least minimum 15 mm at the level of the upper generator of the tube section, acting as an overflow outlet in order to deal with an accidental or exceptional hydraulic overload situation, preferably these perforations are provided at regular intervals and spaced at least 20 cm apart.

9. Sanitation device according to one of the preceding claims, wherein the slope of the series of essentially horizontal tubes (131-136) between the distribution chamber (120) and the ventilation chamber (140) is less than + / - 5%, preferably less than + / - 2%.

10. Sanitation device according to one of the preceding claims, further comprising at the inlet of the distribution chamber (120) a primary filter or pre-filter.

11. Sanitation device according to one of the preceding claims, further comprising upstream of the distribution chamber (120) of the aerobic reactor (10) an all-water septic tank (210), the all-water septic tank being in fluid connection upstream with a wastewater inlet (205) and downstream with a supply of the distribution chamber with water to be purified (115) which connects it to the distribution chamber (120) of the aerobic reactor.

12. A sanitation installation for domestic, agricultural and / or industrial wastewater, the sanitation installation comprising a sanitation device according to one of the preceding claims, the porous cellular concrete tubes of the series of tubes (131-136), the distribution chamber (120) and the ventilation chamber (140) of the aerobic reactor (10) being installed below the ground level (300), so that only upper parts of the passive ventilation chimneys (121, 141) of the aerobic reactor (10) are above the ground level (300).

13. A sanitation installation according to claim 12, wherein the cellular concrete tubes (131-136) are placed on or in a bed of aggregates (310), the aggregates (310) preferably being sand, in particular washed sand.

14. A sanitation installation according to claim 12 or 13, wherein the cellular concrete tubes (131-136) are covered with topsoil (320), a geotextile (510) preferably being placed between the cellular concrete tubes (131-136) and the topsoil (320).

15. Sanitation installation according to one of claims 12 to 14, further comprising one or more collection tubes (350) arranged in below one or more of the porous cellular concrete tubes (131-136) of the aerobic reactor (10), the collection tube(s) (350) being in fluid connection with a lifting and sampling chamber (360), accessible from the outside by a lifting and sampling well (370), where appropriate the collection tube(s) (350) are arranged below the lower level of the aggregate bed (310).

16. A sanitation installation according to claim 15, further comprising a collection geotextile (340) disposed below the collection tube(s) (350).

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