FR2984873A1 - Submerged fixed culture aerobic bioreactor for domestic waste processing, comprises U-shaped chute located in bottom of septic tank on median longitudinal axis of tank, air manifold, and carrying framework for supporting bacterial bed - Google Patents

Abstract

The bioreactor comprises two flanges (2), a plane zone located between an effluents input (3) and the flange nearest to an effluents output (4), strengthening ribs, an U-shaped chute located in a bottom of a septic water tank (1) on a median longitudinal axis of the tank, a separating semi-partition (14), an air manifold, and a carrying framework for supporting a bacterial bed. The tank is made of high density polyethylene and parallelepipedic. The septic tank comprises a removable pre-filter containing a removable net filter located under the flange nearest to the effluents output. The bioreactor comprises two flanges (2), a plane zone located between an effluents input (3) and the flange nearest to an effluents output (4), strengthening ribs, an U-shaped chute located in a bottom of a septic water tank (1) on a median longitudinal axis of the tank, a separating semi-partition (14), an air manifold, and a carrying framework for supporting a bacterial bed. The tank is made of high density polyethylene and parallelepipedic. The septic tank comprises a removable pre-filter containing a removable net filter located under the flange nearest to the effluents output. The carrying framework is horizontally positioned in a middle of the septic tank and rests on the semi-partition, vertically and horizontally on a side of the strengthening ribs and the horizontal strengthening ribs on a front of the tank. The air manifold is a hollow, tubular structure and L-shaped, and includes an ventilation input and a ventilation path prolonged by a perpendicular section comprising a diffuser of fine air bubbles. The ventilation input forms an external part and fixed to the air manifold, and is inserted and placed in a small circular opening. The ventilation path and the perpendicular section comprise an holding element representing an interior removable part of the air manifold. The ventilation path is dimensioned so that the perpendicular section rests in the U-shaped chute. The perpendicular section is dimensioned so that a length of the perpendicular section is lower or equal to 50-55% of a width of the septic tank. The carrying framework comprises four spacers fixed between two lateral sides of the carrying framework and parallel to two frontal sides of the carrying framework. The spacers are laid out in the plane zone of the tank and between the flanges. An interval between the two successive spacers is >= 25 cm. The bacterial bed comprises small blocks of variable sizes superimposed and/or juxtaposed to form a linked block, and is fixed to the spacers on the carrying framework using a iron strip and strapping loops made of rot-resistant plastic to slide the bacterial bed back and forth in a horizontal plane of the carrying framework within limits imposed by the spacers. A clamp made of rot-resistant plastic is inserted between a top of the air manifold and a top of the bacterial bed to prevent the bacterial bed from sliding along the carrying framework. The carrying framework supporting the bacterial bed is assembled from pipes with diameter of 50-32 mm and 90[deg] female/female elbows with a diameter of 50 mm. The blocks are in a form of polyethylene mesh having a large number of cavities and tubes welded together to form cubic blocks. The carrying framework has a flowing region of 70%, a void of 90% and a developing surface of 100 m 2> per m 3>. The air manifold is assembled from pipes with a diameter of 50 mm, a splined end with a diameter of 20 mm, a reducer of type 50 mm/20 mm, two 90[deg] female/female elbows with a diameter of 50 mm, a union with a diameter of 50 mm, a plug with a diameter of 50 mm and the diffuser of air bubbles with a clamp saddle load with a diameter of 50 mm. The diffuser is a standard disc. An independent claim is included for a process for reversible transformation of a septic tank water into an aerobic bioreactor.

Description

The present invention relates to a submerged fixed culture or aerobic bioreactor for the treatment of domestic effluents in addition to anaerobic pretreatment upstream and secondary settling downstream, and a method for the reversible transformation of a septic tank all waters in such a bioreactor. Currently biological reactors or bioreactors (hereinafter simply referred to as a bioreactor (s) for convenience) based on the fixed culture immersed in an aerobic environment are commonly employed for all kinds of industrial applications, and especially in system design. sewage treatment, whether large-scale treatment such as for urban wastewater treatment plants, or small scale as for small standalone sanitation for households not connected at all to the sewer, such as micro-stations. In the context of domestic use, the micro-wastewater treatment plants - also referred to as purification ministries or individual wastewater treatment plants - may consist of either a single compartmentalized vessel (commonly referred to as micro-wastewater treatment plants). monobloc stations), either several compartmentalized tanks (or not), each compartment or tank fulfilling one or more of the functions necessary for an integral treatment of wastewater (example: separation of greases and pre-settling, anaerobic pretreatment, aerobic treatment, settling final before rejection). In the treatment chain mentioned above, the bioreactor is typically intended to provide the aerobic treatment phase. It is also notable that, although the bioreactor is a key piece of this treatment chain, it can not be self-sufficient. In this context, the bioreactor can be implanted either in one of the compartments of the micro-treatment plant, which is typically the case with monobloc compartments, or occupy the entire dedicated tank, which can be met in stations with several tanks.

Document FR-A-2-359-080 discloses a method for treating wastewater using an immersed and aerated bacterial bed, in particular with a device for its implementation based on the use of three holding tanks. series, namely a primary clarifier, a submerged bed bioreactor, and a secondary clarifier. The primary decanter ensures a separation of fats and oils, anaerobic predigestion and a primary settling, according to the same principle as a septic tank all waters. The bioreactor includes a fixed immersed bed and aeration device to provide additional aerobic treatment. Finally, the secondary settling tank receives the effluents treated at the outlet of the bioreactor and stores bottom sludge at the bottom of the tank, so that the effluents thus clarified can be discharged by overflow to the natural environment. More than thirty years later, this method is widely known to those skilled in the art, and advantageously used by different manufacturers throughout the world. If the vessel constituting the envelope of the bioreactor can be made to measure, for example concrete, and likewise for the primary clarifier and the secondary clarifier, it would be particularly advantageous to be able to use a pre-existing septic tank and widespread water. In addition to the advantage, based on models meeting all standards, not to have to "reinvent the wheel", the cost of acquiring a micro-station for the customer wishing to update a Aging standalone sanitation would be less, provided that the client in question has a septic tank all waters still in working order and suitable for reconversion. This septic tank all waters could be concrete or ideally made of a plastic material much lighter, rot and resistant as HDPE (High Density Polyethylene), and would advantageously have a rectangular shape favoring the implementation of the elements necessary for its transformation reversible bioreactor. The reversibility character of this transformation would have the advantage of the possibility of restoring the tank to its initial state of septic tank, by simply removing the fixed bed and the aeration system, an operation implying that the prior transformation into a bioreactor has been carried out. performed in a particularly respectful manner of the integrity of the tank. US-A1-2003-066-790 and US-B1-6-554-996 disclose a device for converting a typical anaerobic septic tank into an aerobic wastewater treatment system using a foldable bioreactor whose insertion into the tank is carried out via a manhole, which bioreactor once unfolded is held in place by a set of secure straps at the inspection pad. Although attractive and having a priori character of reversibility, this solution provides a recirculation of effluents within the bioreactor, repeated as many times as necessary until satisfactory treatment, and its implementation is generally uncomfortable. WO-A2-2008-125-684 proposes a process for converting an all-water septic tank into a biological sewage treatment plant, but the method used is based on the activated sludge technique. with effluent recirculation, and not on immersed fixed culture technique. As its name suggests, the fixed culture immersed in an aerobic environment implies that the bioreactor has at least the following characteristics: firstly the presence in the tank or compartment of a structured support called fixed bed, on which the micro aerobic organisms initially in suspension will preferentially cling and thus form a protective medium called bio film, and secondly the presence of a fine-bubble aeration device typically based on one or more micro membrane (s) -perforée (s) of the tube or disk type, ensuring the production of a micro-bubbling under the fixed bed. Structured support, or fixed bed, can have multiple shapes and be made in many materials well known to those skilled in the art. For example, FR-A1-2-768-141 proposes an immersed fixed-bed micro-stationary treatment plant comprising vertically stretched tissue webs as a support for the micro-organisms. Document FR-A1-2-811-658 describes an immersed fixed-bed bioreactor in which the support for the microorganisms consists of polypropylene swabs or bottle brushes placed in a basket. Regardless of the support envisaged to serve as fixed bed in a bioreactor, certain technical imperatives must guide the final choice. Insofar as the support in question will be immersed in a constant manner in a liquid medium and subjected to the more or less corroding action of the pretreated effluents in the anoxic phase, it must be made of a rot-proof material resistant to attack chemical. It must also have a rough and porous surface to promote the attachment of biomass, that is to say all microorganisms ensuring the degradation of pollutants, so that said biomass forms a bio film promoting the development of new microorganisms. The structured support, or fixed bed, must also have a sufficient vacuum index to allow the free passage of effluents and prevent any risk of clogging. Finally, it should ideally develop a support surface of 100 m2 per m3, in accordance with standard NF EN 12255-7. The documents US-A-5-882-510 and AU-A1-2007-231-766 describe a structured support that responds particularly advantageously to the specifications defined above. This support is in the form of polyethylene mesh tubes having a large number of cavities, tubes welded together to form typically a cubic block. Produced by various manufacturers throughout the world, this carrier is well known to those skilled in the art, and arguably the most commonly used in water treatment devices based on fixed immersed culture. The aeration device can also have different shapes and be designed in different materials, again well known to those skilled in the art. Typically, there will be aeration devices based on membranes of the tube or disk type, made of materials such as ceramic or more commonly in flexible plastics such as EPDM (Ethylene Propylene Diene Monomer), and comprising a multitude of micro-perforations. When air is sent into this device, using an electric pump (called compressor, blower or blower as appropriate) usually installed outside the wastewater treatment plant and connected by a flexible hose at the air manifold provided for this purpose on the bioreactor, a microbulling is produced and escapes from the membrane (s).

The resulting oxygenation allows the development of aerobic biomass, the flow product also promoting the mixing of organic materials and the movement of effluents through the fixed bed. US 2003192817 A1 discloses a typical fine bubble diffuser consisting of a disk type membrane and a saddle attachment. This device, well known to those skilled in the art, is intended to be connected to an air supply pipe, for example a high pressure PVC pipe. Although having proven its worth, the water purification process by the fixed culture immersed in an aerobic environment requires taking certain precautions during its implementation, more particularly in the pre-assembled and ready-to-use devices. what are the micro-stations. If the choice of bacterial carrier, or fixed bed, is an important factor, the way it is going to be implanted in the bioreactor is just as important: it is necessary to be able to prevent incidents such as a displacement, a fall in the bottom the tank or clogging of the support, while ensuring easy access for cleaning or possible removal for replacement.

WO-A1-9-315-024 relates to metal frames for supporting bacterial bed blocks, which frames can be individually inserted or removed from the vessel constituting the bioreactor. DE-C1-43-36-787 discloses a sophisticated framework combining a support for the bacterial bed blocks with an aeration system based on tubular membrane diffusers. EP-A2-1-078-886 relates to a fixed bed consisting of bacterial support blocks in the form of columns which can be individually hoisted out of the bed for inspection purposes, which is comparable to the solution proposed by WO-A1-9-315-024. The document DE-A1-100-17537 proposes to keep in place blocks of bacterial bed using a complex frame, based on rods, spacers, metal beams, designed in such a way that one can go down or up all the blocks in one operation. Without wishing to prejudge the advantages provided in absolute terms by these different solutions, their implementation outside the collective or even semi-collective concrete treatment plants mounted on site, with their traditional open ponds, does not seem relevant. . The document FR-A1-2-796-933 proposes a simpler and more economical solution than the solutions mentioned above, in particular in that it does not require any frame or chassis to keep the bacterial bed blocks at the bottom of the pond, this being achieved by the mere weight of these same blocks. Still in the field of precautions to be taken during the implementation of the water purification process by the fixed culture immersed in an aerobic environment, and more particularly in the pre-assembled and ready-to-use devices that are the micro It should be ensured that the micro-perforated membrane aeration device is designed and installed in the bioreactor so that it can be easily and quickly removed at any time. Indeed, the micro-perforated membranes wear out over time, and are likely to clog, which necessarily entails the need to clean them and / or replace them one day or the other. However, it is most advantageous and economic to be able to deposit the aeration system without stopping the micro-station for several hours, and without having to drain the tank or deposit the fixed bed. In this scenario, in addition to the fact that the restart of the micro-station and its optimal operation will immediately follow the refitting of the aeration system, implying that there will be no decrease in the purification performances which may lead to the appearance of olfactory nuisance and / or degraded quality of rejection, the cost of the intervention for the client will be much lower. For this purpose JP-A-57-184-492 discloses a rotary aeration device which can be put in place and removed by means of a central trench arranged in the bacterial bed and extending over the entire height of the bioreactor. JP-A-4-078-490 relates to a flexible aeration device, which can be placed and deposited by means of a guide rail fixed along the wall and on the bottom of the bioreactor. EP-A1-1-293-483 relates to a flexible aeration device, the microbubble diffusing portion is maintained pressed against the underside of the bacterial bed by the single thrust produced by the diffused air. However, these solutions are not entirely satisfactory because there remains the need for a process for the simple and economical conversion of an all-water septic tank into an aerobic bioreactor fixed immersed culture, said transformation also having the character of reversibility , and said bioreactor naturally finding its place in a small autonomous sanitation installation.

An object of the present invention is therefore to solve the problems mentioned above, using a simple solution to manufacture, inexpensive, easy to use and optimized in terms of efficiency. In the text that follows, the term "tank" refers to both the septic tank all waters and the aerobic fixed-immersed aerobic bioreactor obtained by the transformation of the septic tank all waters according to the present invention. Thus, the present invention relates to an aerobic fixed-immersed aerobic bioreactor for the treatment of domestic effluents in addition to anaerobic pretreatment upstream and secondary settling downstream, designed on the basis of a septic tank all waters made of high density polyethylene, of substantially parallelepiped shape and comprising in particular two inspection buffers, a flat zone situated between an effluent inlet 30 and the nearest inspection buffer, an effluent outlet, reinforcing ribs , a channel U at the bottom of the tank on the median longitudinal axis of the tank, and a semi-partition bottom separation, characterized in that it further comprises a ventilation ramp and a carrier frame internal 35 for supporting a bacterial bed.

According to preferred embodiments, the submerged fixed culture aerobic bioreactor according to the present invention comprises at least one of the following characteristics: the all-water septic tank comprises a removable decolloid (pre) filter containing a removable filter net situated under the survey buffer closest to the effluent outlet; the support frame is positioned horizontally and half-way in the all-water septic tank and it rests on the separating half-sheet, lateral vertical and lateral reinforcing ribs and frontal horizontal reinforcing ribs of the pit; the ventilation ramp is a hollow, tubular L-shaped structure consisting of a ventilation inlet, a ventilation downcomer extending by a perpendicular section comprising at least one bubble air diffuser, the aeration inlet of the ventilation ramp forms an outer and fixed part of the ventilation ramp and is inserted and glued in a small circular opening, and the aeration down and the perpendicular section of the ramp of aeration constitute an integral element, representing the inner and removable part of the ventilation ramp; the aeration ramp of the ventilation ramp is dimensioned so that the perpendicular section of said ramp rests in the U-shaped chute, and the perpendicular section is dimensioned so that its length is less than or equal to at about 45 to 60% of the width of the septic tank all waters, preferably about 50-55%; - The carrier frame comprises between two and six spacers, and preferably four spacers, fixed between two lateral sides of the carrier frame, and therefore parallel to two front sides of the latter, the set of spacers is disposed in the pit area septic all waters between the two tampons, and the interval between two successive spacers is greater than or equal to twenty-five centimeters; The bacterial bed consists of several small blocks of variable sizes that are superimposed or / and juxtaposed to form a united block, said bed being fixed to the support frame at the spacers by means of a strapping strapping and self-locking loops of rotproof plastic so as to allow, if necessary, to slide the bacterial bed from front to back and vice versa on a horizontal plane along the support frame, within the limits imposed by the spacers, and a The rot-proof plastic clamp is inserted between the top of the vent ramp and the top of the bacterial bed so as to prevent the bacterial bed from sliding along the carrier frame; the supporting frame supporting the bacterial bed is assembled from tubes 50 mm and 32 mm in diameter respectively, as well as 90 ° female / female bends with a diameter of 50 mm, the structured support blocks constituting the bacterial bed are presented under the form of polyethylene mesh tubes having a large number of cavities and tubes welded together to form typically cubic blocks, this structured support having a flow area of at least 70%, a void percentage of minus 90%, and developing an area of 100 m 2 per m 3, and the ventilation ramp 20 is assembled from pipes with a diameter of 50 mm, a corrugated end with a diameter of 20 mm, a reduction of 50 mm / 20 mm, at least two female / female 90 ° bends with a diameter of 50 mm, a 50 mm diameter union, at least one 50 mm diameter stopper, and at least one diffuser fine air bubbles with its grip collar 25 in diameter 50 mm X ; - The pipes and bends constituting the carrier frame are made of any imputrescible material, and preferably polyvinyl chloride, the elements constituting the ventilation ramp, with the exception of the micro-perforated membrane of the fine air diffuser 30 bubbles, are made of any imputrescible material, and preferably high-pressure polyvinyl chloride, and the (or) thin bubble air diffuser (s) is (are) of the disk type, and comprises (s) a micro membrane -perforated ethylene propylene diene monomer. The present invention also relates to a process for the reversible conversion of an all-water septic tank into a submerged fixed culture or aerobic bioreactor for the treatment of domestic effluents in addition to anaerobic pretreatment upstream and downstream. a secondary settling downstream, characterized in that, the septic tank all waters comprising in particular two inspection pads, a flat area located between an effluent inlet and the nearest inspection pad, reinforcing ribs, a chute U-shaped located at the bottom of tank on the median longitudinal axis of the tank, as well as a semicloison separation, - a small circular opening is practiced on the top of the septic tank all waters in the flat area located between the entrance effluent and the nearest inspection buffer, said planar zone being traversed at its center by a median longitudinal weld line of the septic tank, and - introduced into the septic tank all waters a device 15 comprising a support frame for supporting a bacterial bed, said bacterial bed to be fixed on said carrier frame, and a ventilation ramp. Advantageously, the septic tank is provided with all waters of a removable (pre) decolloid filter containing a removable filter net located under the inspection buffer closest to the outlet of the effluents, and the small circular opening made on the top of the tank. septic tank all waters has a diameter adapted to allow the insertion and gluing in the same opening of a ventilation inlet corresponding to the upper and outer part of the ventilation ramp. According to an alternative, the all-water septic tank initially comprising a removable pre-decolloid filter containing a filtering net located under the inspection buffer closest to the outlet of the effluents, said removable decolloidal pre-filter is removed and the sleeve is removed. right out of the tank is replaced by a dip tube while the small circular opening on the top of the septic tank all water has a suitable diameter to allow insertion and bonding in the same opening of a ventilation inlet corresponding to the upper and outer part 35 of the ventilation ramp.

Preferably, the support frame is positioned horizontally and at mid-height in the septic tank all waters, it is designed and dimensioned so that it is in contact with the inner side walls and front of the septic tank all water, and that the semi-partition, the vertical and horizontal lateral reinforcing ribs and the frontal horizontal reinforcing ribs of the all-water septic tank constitute support points to maintain it in its horizontal position and at mid-height .

Thus, the solution of the present invention makes it possible to avoid fixing the bacterial bed by a process that would involve damaging the septic tank all waters at various points, which would be the case with for example threaded rods passing through the ceiling of the tank. and bolted to the same ceiling.

To improve the attachment of the carrier frame it is provided that the two lateral sides of the same carrier frame have at least two pins or studs, positioned and dimensioned so as to be nested in the concave areas located between the lateral vertical reinforcing ribs of the septic tank all waters. The carrier frame is not fixed definitively or hardly reversible by processes such as welding, gluing, screwing, bolting the walls of the tank, but rather by simple casing. If necessary, it is therefore quite possible to disassemble the carrier frame without damaging any element constituting the septic tank all waters, making it reversibly convertible. The carrier frame further comprises spacers for supporting the bacterial bed and fixed between the two lateral sides of said frame, these spacers being parallel to the two front sides of the same carrier frame. Depending on the amount of structured support constituting the bacterial bed block that is to be inserted into the septic tank all waters, the number of these spacers varies between two and six, and is preferably four. The interval between two successive spacers is greater than or equal to twenty-five centimeters, and the set of spacers is arranged in the zone of the septic tank all waters between the two inspection pads of the same tank, so that no spacer will impede access to the interior of the septic tank all waters via manholes.

Another advantage is that the support frame can be made with elements commonly used in plumbing and easy to procure and low cost. These elements are pipes and bends that can be made of various materials, provided that these materials are rot-proof and resistant to corrosion exerted by domestic wastewater. Ideally, these pipes and elbows are made of a light but very strong plastic material, used in the manufacture of plumbing articles, such as but not limited to Polyethylene (PE), High Density Polyethylene (HDPE), Polypropylene (PP), Polybutene (PB), Polyester Reinforced Glass Fiber (GRP), Polyvinyl Chloride (PVC). These elements are assembled by casing and the cohesion of the assembly can, if necessary, be obtained by any suitable method, including bonding, bolting or riveting.

As indicated above, the method according to the invention also provides to insert into the septic tank all waters a bacterial bed, which bed rests on the carrier frame, at the spacers of the same frame. The bacterial bed consists of smaller blocks of structured support, blocks whose number and size are variable, and that is inserted into the septic tank all waters by passing through any of the two manholes . We can then superimpose or / and juxtapose these blocks within the septic tank all water by resting them on the spacers of the carrier frame, and ensure the cohesion of the bacterial bed thus formed by using any appropriate method, including non-limiting way by gluing, stapling, binding by means of clamps or clamps plastic rot. Once the bacterial bed formed and correctly positioned, it is fixed on the support frame at the spacers of the same frame, using strapping and self-locking loops. The strapping strapping may be made of any suitable rotproof material, such as but not limited to Polyester, Polypropylene (PP), Polyethylene Terephthalate (PET). The self-locking buckles are also made of rot-proof plastic material. Several widths of strip and loop exist on the market, having various tensile strengths depending in particular on the material used, but in the context of the present invention, a basic sheet of polypropylene sheet (PP) of a width 12 mm and a thickness of 0.4 mm, with its self-locking loops plastic adapted size, is quite appropriate. In the same way as for the carrier frame, the ventilation ramp can advantageously be made with elements commonly used in plumbing, items whose supply is easy and the cost is low. These elements are pipes, splined ends, reductions, elbows, unions, plugs, which can be made of various rot-resistant materials and resistant to corrosion by domestic wastewater. Ideally, these pipes and elbows are made of a lightweight but very strong plastic material used in the manufacture of plumbing articles, such as but not limited to Polyethylene (PE), High Density Polyethylene (HDPE) , Polypropylene (PP), Polybutene (PB), Polyester Reinforced Glass Fiber (GRP), Polyvinyl Chloride (PVC). These 25 elements are assembled by fitting, gluing and screwing. Any type of fine bubble air diffuser is potentially usable, whether it is a tube-shaped or disk-shaped diffuser, based on materials such as ceramic or on a plastic membrane such as silicone . According to a preferred embodiment of the present invention, the fine air bubble diffuser is of the EPDM membrane type (Ethylene Propylene Diene Monomer), offering good resistance to attack by domestic wastewater, and ensuring an ideal micro-bubbling distribution under the fixed bacterial bed.

In the context of the present invention, the ventilation ramp must be easily introduced into or removed from the septic tank all waters, for cleaning or replacement of (the) diffuser (s) of fine air bubbles, and this without needing to drain the tank or to deposit the bacterial bed. To do this, as indicated above, the ventilation ramp consists of a fixed part, namely the ventilation inlet, and a removable part, namely the lowering of ventilation. The invention will now be described in more detail with reference to particular embodiments given by way of illustration only and shown in the appended figures in which: FIGS. 1 and 2 respectively show a schematic view in longitudinal section and a schematic top view of an immersed fixed culture aerobic bioreactor according to an advantageous embodiment of the present invention; - Figures 3 and 4 show a schematic top view of a frame for supporting the bacterial bed, respectively exploded view and assembled view; and - Figures 5 and 6 show a schematic longitudinal sectional view of a ventilation ramp, respectively exploded view and assembled view; and FIG. 7 is a view similar to FIG. 2 prior to the installation of the ventilation ramp, a support frame and a bacterial bed. FIGS. 1 and 2 illustrate an aerobic bioreactor with immersed fixed culture B, produced according to the invention from a septic tank model with all waters having a useful volume of 2000 liters, and also having all the characteristics already mentioned above. before in the preamble of the description. For the sake of clarity and brevity, Figures 1 and 2 do not show the completeness of the characteristics of the all-water septic tank 1. In particular, neither the horizontal and vertical reinforcement ribs of known type, nor the chute in U located at the bottom of the tank are not shown.

This septic tank all waters 1 has two inspection buffers 2, an inlet for the effluents 3, an outlet for the effluents 4 lower than the inlet 3 to allow the flow of the effluents by gravity, a decolloid (pre) filter 12 removable removable filter and located under the visit pad 2 closest to the effluent outlet 4, and a separation semicloison 14. The septic tank all waters 1 also has a ventilation inlet 5 corresponding to the upper and outer part of a ventilation ramp 6 comprising two thin air bubbles diffusers 7 of the micro-perforated membrane disc type, and a bacterial bed 8 fixed with the strap 9 to a carrier frame 11. According to the invention , the bacterial bed 8 is fixed to the carrying frame 11 with strapping band 9 and self-locking rot-proof plastic loops (not shown in FIGS. 1 and 2), so that it is possible, if necessary, to slide the bacterial bed 8 on a horizontal plane along the support frame 11. Thus a clamping collar 10 connects the ventilation ramp 6 to the bacterial bed 8, in order to prevent the bacterial bed 8 from sliding in such a way that inadvertent during any handling operation of the bioreactor. The choice of the clamp 10 is not essential, from the moment it is made of a rotproof material, such as for example and without limitation a plastic such as Polyamide (PA), Polyethylene (PE) Polypropylene (PP). The clamping collar 10 is placed between the top of the ventilation ramp 6 and the top of the bacterial bed 8, so as to be as close as possible to the inspection buffer 2 closest to the effluent inlet 3, so easily accessible.

In FIGS. 3 and 4, it can be seen that the support frame 11 is assembled from two identical pipes 15 corresponding to the front sides of the support frame 11, of two identical pipes 16 corresponding to the lateral sides of the support frame 11, of four pipes. 17 corresponding to the spacers of the carrier frame 11 on which rests the bacterial bed 8, four identical pipes 18 corresponding to the dowels or studs to strengthen the attachment of the carrier frame 11 to the walls of the septic tank all waters 1, and finally four 90 ° elbows female / female 19. In Figure 5, we can see the various elements 5 constituting the ventilation ramp 6, namely: a splined nozzle 20, a reduction 21, two bends 90 ° female / female 22 , a sleeve 23, a union 24, a length of pipe 25, another length of pipe 26, a plug 27, two support collars 28, and two thin air bubbles 7 of the membrane disk type e 10 micro-perforated. In FIG. 6, it is possible to see the fully assembled ventilation ramp 6, where the ventilation inlet 5 corresponds to the assembly of the splined end piece 20, of the reduction 21, of a female 90 ° elbow. / female 22, the sleeve 23, and finally the upper part 15 of the union 24. To further explain the proposed embodiment, hereinafter will be found a precise protocol exposing the detailed manufacture and assembly in the septic tank all waters of a carrier frame for bacterial bed, as well as the detailed manufacture of a ventilation ramp, followed by the manner of inserting it in or removing it from the septic tank all waters. The elements used in the manufacture of the support frame and the ventilation ramp are elements PVC (Polyvinyl Chloride) commonly used in plumbing, the air diffusers 25 fine bubbles being of the disk type micro-perforated membrane EPDM (Ethylene Propylene Diene Monomer) with a diameter of 270 mm. At the end of the operations described below, an aerobic bioreactor with a fixed immersed culture B with a capacity of 2000 liters, fully functional and easy to maintain, is obtained.

30 Manufacture of the support frame for septic tank all waters of 2000 liters. 1st step: - Cut two lengths of drain pipe 15 with a diameter of 50 mm and a length of 520 mm. 35 - Cut two lengths of drain pipe 16 with a diameter of 50 mm and a length of 1680 mm. - Cut four lengths of pipe 17 of diameter 32 mm and length 655 mm, - cut four lengths of drain pipe 18 of diameter 32 mm and length 280 mm, and - assemble four elbows at 90 ° female / female 19 of diameter 50 mm . Step 2: - Drill the first 1680 mm pipe 16 with a 33 mm diameter hole saw at a length of 180 mm from each end of the pipe, passing through only one wall of the same pipe, - Perform the latter operation also on the second pipe 16 of 1680 mm, - Fit two lengths of 280 mm in the two holes previously drilled on the first pipe 16 of 1680 mm, 15 - Fit the other two lengths of 280 mm in the two holes beforehand pierced on the second pipe 16 of 1680 mm, - Drill right through the previously nested assembly and rivet the whole, on a plane perpendicular to the four pipes 18 of length 280 mm, so that the latter are 20 firmly fixed - Drill the first pipe 16 1680 mm four holes with a hole saw 33 mm in diameter, this on a parallel plane but on the opposite wall relative to the holes already drilled to 180 mm from each end; The first hole will be placed at a distance of 25,520 mm from the top of the pipe, the other three holes will be spaced 250 mm apart, one with respect to the other, and - Perform this last operation also on the second pipe 16 1680 mm. Mounting of the support frame in the septic tank all waters of 30 2000 liters. 1st step: - Encase a first 90 ° female / female elbow 19 of diameter 50 with the first flow pipe 15 of diameter 50 and length 520 mm on one side, then nest the other part of this same first 35 elbow 19 with the first flow pipe 16 of diameter 50 and length 1680 mm, and support the assembly in the middle of the tank on the support thereof, - Encase the second length 16 of 1680 mm in the second bend 19 and fit the other part of this same second bend 19 into the first pipe 15 of length 520 mm, - fit the other end of the second pipe 16 of length 1680 mm in the third bend 19, and then fit the second pipe 15 of length 520 mm in the other part of the third bend 19, - fit the fourth bend 19 between the first pipe 16 with a length of 1680 mm and the second pipe 15 with a length of 520 mm, - the four pipes 18 with a length of 280 mm must be placed horizontally in relation to the tank, and - the four lengths of 655 mm in the four holes of the two lengths of 1680 mm. Step 2: - Drill right through the previously nested assembly and rivet the whole, on a plane perpendicular to the four pipes 17 655 mm in length, so that they are securely fixed.

20 Manufacture of aeration ramp for septic tank all waters of 2000 liters. 1st step: - Cut a length of high pressure pipe 23 with a diameter of 50 mm and a length of 67 mm, 25 - cut a length of high pressure pipe 25 with a diameter of 50 mm and a length of 1170 mm, - cut a length of high pressure pipe 26 diameter 50 mm and length 580 mm, - deburr the two sides of previously cut pipes, and 30 - gather a high pressure 20 barb end 20 mm diameter, a high pressure reduction 21 type 50 mm / 20 mm, two High pressure elbows at 90 ° female / female 22 of diameter 50 mm, a high pressure union 24 of diameter 50 mm, a high pressure stopper 27 of diameter 50 mm, two clamps of support 28 35 in 50 mm X (hole 18 mm), two fine air bubbles diffusers 7 of the EPDM micro-perforated membrane disk type with a diameter of 270 mm. Step 2: - Glue the splined end 20 with the reduction 21, - Glue the assembly 20/21 with a first elbow 22, - Glue the assembly 20/21/22 with the sleeve 23, - Glue the union 24 by its lower part with the length of 1170 mm, - glue the other end of the length of 1170 mm with the second bend at 90 ° female / female 22, - glue (inside-outside gluing) the length 26 of 580 10 mm with the other part of the second elbow 22, and - glue the plug 27 of diameter 50 on the length 26 of 580 mm. 3rd step: - Screw a first support collar 28 of the 15 fine bubble air diffusers at a distance of 105 mm from the edge of the plug 27 to the length 26 of 580 mm, - screw the second support collar 28 at a distance of 310 mm from the middle of the first support collar 28 already screwed on the length 26 of 580 mm, 20 - Drill the two support collars 28 in diameter 18 mm over the length 26 of 580 mm, - cover with Teflon (registered trademark) the two fine air bubbles 7 diffusers over the entire screw thread, and - Completely screw the two fine air bubbles diffusers 7 25 on the two support collars 28. Setting initial position of the ventilation ramp in the septic tank all waters of 2000 liters: - Open the inspection buffer 2 closest to the effluent inlet 3 of the tank, 30 - Shift the bacterial bed 8 from the front towards the rear, in order to facilitate the installation of the ventilation ramp 6, - Perc with a hole saw, a hole T 50 mm in diameter in the middle of the right half of the planar zone located between the effluent inlet 3 and the nearest inspection buffer 2, which plane zone is traversed in the middle by a median longitudinal weld line XX 'of the vessel; In the end, the hole T must be at a distance of between 30 and 40 mm to the right of this same welding line XX ', - Insert the ventilation ramp 6 at the manhole closest to the entering the effluent 3 of the septic tank all waters 1, and place the length 26 of 580 mm of the ventilation ramp 6 so that it enters the U channel located at the bottom of the tank, - orient the length of 25 1170 mm of the ventilation ramp 6 so as to place the upper part of the union 24 below the hole T 10 with a diameter of 50 mm of the aeration inlet of the tank, - Take the assembly previously glued 20 / 21/22/23, and put a net of urethane sealant at the joint between the bend 22 and the sleeve 23, so as to provide a seal between the tank and the assembly 20/21/22/23, set corresponding to the aeration inlet 5, - Glue the assembly 20/21/22/23 with its urethane filler net into the hole T of the tank, as well as into the union 24 by its upper part, previously placed below the hole T, - to shift forward the bacterial bed 8, so as to put it back in its initial place, just above the two fine air bubbles diffusers 7, and - Take a rotproof plastic clamp 10, and hook with the ventilation ramp 6 to the bacterial bed 8, as can be seen in Figure 1, so that this clamp 10 is the as close as possible to the manhole closest to the effluent inlet 3 of the tank. Disassembly (removal) of the ventilation ramp 6, for control purposes of the fine bubble air diffusers: - Open the inspection buffer 2 closest to the entrance of the 30 effluents 3 of the septic tank all waters 1 - Cut the rotatable plastic collar 10 between the ventilation ramp 6 and the bacterial bed 8, - Move the bacterial bed 8 towards the rear of the tub, - Unscrew union 24, so as to separate the ventilation ramp 6 of the ventilation inlet 5, and - Pull up the ventilation ramp 6 by turning it 90 ° to the right so as not to remain stuck on the support frame 11. Logically, after the control of the thin air diffusers 5 bubbles 7, and their cleaning or replacement, we will replace the ventilation ramp 6 as follows: - Insert the ventilation ramp 6 by the manhole closest to the effluent inlet 3 of the septic tank all waters 1, and place along 5 mm from the ventilation ramp 6 so that it enters the U-shaped chute located at the bottom of the tank, - orienting the length 1170 mm of the ventilation ramp 6 so as to be able to screw the union 24, and thus secure again the ventilation inlet 5 and the ventilation ramp 6, - Move the bacterial bed 8 towards the front of the tank, so as to put it back in its original place, just above the two fine air bubbles diffusers 7, and - Put a rotproof plastic clamp 10, as already described above. The present invention will naturally find its place in a micro-purification station designed for the purpose of treating domestic effluents according to the standards in force, and whose purification process implemented is that of the fixed culture immersed in an aerobic environment. The operation according to the present invention can not be simpler. According to a particularly refined embodiment of a small individual sanitation installation for the treatment of domestic effluents in compliance with the standards in force, the immersed fixed culture aerobic bioreactor B according to the present invention is completed by a primary decanter in upstream 30 and a secondary settler downstream. The primary decanter ensures a separation of fats and oils, anaerobic predigestion and a primary settling, according to the same principle as a septic tank all waters. The bioreactor provides the additional aerobic treatment of pretreated effluents. Finally, the secondary settling tank receives the treated effluents from the bioreactor and stores the secondary sludge at the bottom of the tank so that the effluents thus clarified can be discharged by overflow into the natural environment. There is no electromechanical device to ensure the flow of effluents from one tank to another, the movement of effluents being only by overflow. The only electrical device is an air pump, commonly known as a booster, a pump installed outside the tanks in a room of the house or a technical room for example, and connected to the aeration of the bioreactor via a flexible hose made of plastic material. The booster works continuously, so no analog or digital programmer is needed. Such a micro-station will typically, but not exclusively, consist of three HDPE (High Density Polyethylene) tanks connected in series, the first tank providing a primary settling, a separation of oils and fats and an anaerobic predigestion, the second The vessel being a bioreactor made according to the present invention and providing an aerobic digestion of pretreated effluents in the anaerobic phase, the third tank ultimately ensuring a secondary settling before rejection of purified water in the natural environment. It goes without saying that the detailed description of the subject of the invention, given solely by way of illustration, does not in any way constitute a limitation, the technical equivalents also being included in the scope of the present invention.

Thus, it is not necessary to leave the (pre) decolloid filter 12 and filter net 13 in the septic tank all waters 1. It is for example possible to remove from the septic tank all waters 1 (pre) filter decolloid 12 and the filter net 13, then replace the right sleeve of the effluent outlet 4 by a dip tube. Indeed, due to micro-bubbling, the materials removed from the bacterial bed remain in suspension in the wastewater, and must be able to be discharged to the secondary decanter: this is why, when removing the (pre) decolloid filter and its filter net, it is necessary to replace the straight sleeve at the outlet of the bioreactor (straight sleeve which was then connected to the outlet of the (pre) filter) by a dip tube, so that the substances in suspension in the liquid pass into the clarifier secondary, through the dip tube. When the (pre) filter and its net are left in place, they play the role of the dip tube (among others). Thus, if, in the context of a conventional use of the septic tank all waters, the (pre) decolloid filter and its filter net are essential accessories, it is not the same with an aerobic bioreactor fixed culture immersed In such a bioreactor, the forced and permanent oxygenation of the medium allows the development of bacteria different from those found in the anaerobic environment of all-water septic tanks, and the development of a large aerobic biomass will make it possible to degrade the materials (pretreated to about 30-35% in the anaerobic phase of the primary clarifier, upstream of the bioreactor) up to 92-95%, resulting in very low residual and very low pollutant sludge production: this low quantity of sludge will be found in the secondary clarifier, downstream of the bioreactor. Thus, a simple dip tube (without filtration) will do the job in a bioreactor, while in the context of a septic tank all waters, it is essential to set up a filtration outlet tank. The model septic all water chosen can have different useful volumes, including two particularly advantageous capabilities in the context of the present invention, namely 2000 liters and 3000 liters, the dimensions of the two models differ only at the level of length of the tank.

Claims (13)

REVENDICATIONS1. An aerobic bioreactor with immersed fixed culture (B) intended for the treatment of domestic effluents in addition to anaerobic pretreatment upstream and secondary settling downstream, designed on the basis of an all-water septic tank (1) realized in high density polyethylene of substantially parallelepipedic shape and comprising in particular two inspection buffers (2), a flat zone situated between an effluent inlet (3) and the nearest inspection buffer, an effluent outlet (4), reinforcing ribs, a channel U at the bottom of the tank on the median longitudinal axis of the tank, and a bottom half-partition (14), characterized in that it further comprises a ramp of aeration (6) and an internal carrier frame (11) for supporting a bacterial bed (8). 2. aerobic fixed culture immersed bioreactor (B) according to claim 1, characterized in that the septic tank all waters (1) comprises a removable (pre) decolloidal filter (12) containing a removable filter net (13) located under the inspection buffer (2) closest to the effluent outlet (4). 3. A submerged fixed culture aerobic bioreactor (B) according to claim 1 or claim 2, characterized in that the carrier frame (11) is positioned horizontally and at mid-height in the septic tank all waters (1). and it rests on the semi-partition wall (14), lateral vertical and horizontal reinforcement ribs and frontal horizontal reinforcing ribs of the pit (1). 4. A submerged fixed culture aerobic bioreactor (B) according to any one of the preceding claims, characterized in that: - the aeration ramp (6) is a hollow, tubular L-shaped structure consisting of an inlet of aeration (5), a ventilation downcomer (25) extending by a perpendicular section (26) comprising at least one fine air bubble diffuser (7), - the ventilation inlet (5) of the ventilation ramp (6) forms an outer and fixed part of the ventilation ramp (6) and is inserted and glued into a small circular opening, and the aeration chute (25) and the perpendicular section ( 26) of the ventilation ramp (6) constitute an integral element, representing the inner and removable part of the ventilation ramp (6). 5. immersed fixed culture aerobic bioreactor (B) according to claim 4, characterized in that: - the aeration down (25) of the ventilation ramp (6) is dimensioned so that the perpendicular section ( 26) of said ramp rests in the U-shaped chute, and - the perpendicular section (26) is dimensioned so that its length is less than or equal to about 45 to 60% of the width of the all-water septic tank (1). ), preferably about 50-55%. 6. aerobic bioreactor immersed fixed culture (B) according to claim 5, characterized in that: - the carrier frame (11) comprises between two and six spacers (17), and preferably four spacers (17), fixed between two lateral sides (16) of the support frame (11), and therefore parallel to two front sides (15) of the latter, 20 - the set of spacers (17) is arranged in the area of the septic tank all waters (1) between the two inspection buffers (2), and - the interval between two spacers (17) successive is greater than or equal to twenty-five centimeters. 25 7. A submerged fixed culture aerobic bioreactor (B) according to claim 6, characterized in that: - the bacterial bed (8) consists of several small blocks of variable sizes that are superimposed or / and juxtaposed to form a united block , The bacterial bed (8) is fixed on the support frame (11) at the level of the struts (17) by means of a strap (9) for strapping and self-locking buckles made of rot-proof plastic material so as to allow if necessary, to slide the bacterial bed (8) back and forth horizontally along the support frame (11), within the limits imposed by the spacers (17), - a clamping collar rotproof plastics material (10) is inserted between the top of the ventilation ramp (6) and the top of the bacterial bed (8) so as to prevent the bacterial bed (8) from sliding along the carrier frame (11) . 8. aerobic bioreactor with submerged fixed culture (B) according to claim 7, characterized in that: - the support frame (11) supporting the bacterial bed (8) is assembled from pipes (15, 16; 17, 18). 50 mm and 32 mm diameter, as well as 90 ° female / female bends 10 (19) with a diameter of 50 mm, the structured support blocks constituting the bacterial bed (8) are in the form of screened tubes. polyethylene having a large number of cavities and tubes welded together to form typically cubic blocks, said structured support having a flow area of at least 70%, a void percentage of at least 90%, and developing an area of 100 m2 per m3, and - the ventilation ramp (6) is assembled from pipes (23, 25, 26) with a diameter of 50 mm, a splined end piece (20) with a diameter of 20 mm, d a reduction (21) of the type 50 mm / 20 mm, of at least two bends 20 to 90 ° female / female (22) of diameter 50 mm, a union (24) with a diameter of 50 mm, at least one stopper (27) with a diameter of 50 mm, at least one fine bubble air diffuser (7) with its support collar ( 28) of diameter 50 mm X. 9. A submerged fixed culture aerobic bioreactor (B) according to claim 8, characterized in that: - the pipes and bends constituting the carrier frame (11) are made of any imputrescible material, and preferably of polyvinyl chloride, the elements constituting the ventilation ramp (6), with the exception of the micro-perforated membrane of the fine bubble air diffuser (7), are made of any imputrescible material, and preferably of high polyvinyl chloride; pressure, and - the bubble air diffuser (s) (7) is (are) of the disc type, and comprises (s) a micro-perforated membrane ethylene propylene diene monomer. 10. Process for the reversible transformation of an all-water septic tank (1) into a submerged fixed culture (B) biological reactor or aerobic bioreactor for the treatment of domestic effluents in addition to anaerobic pretreatment upstream and downstream. a secondary settling downstream, characterized in that, the septic tank all waters (1) comprising in particular two inspection buffers (2), a flat area located between an effluent inlet (3) and the nearest inspection buffer , reinforcing ribs, a U-shaped channel located at the bottom of the tank on the median longitudinal axis of the tank, as well as a semi-partition wall (14), - a small circular opening (T) is made on the above the septic tank all waters (1) in the flat zone located between the effluent inlet (3) and the nearest inspection buffer (2), said flat area being traversed at its center by a weld line median longitudinal of the pit septic (1), and - there is introduced into the septic tank all waters (1) a device comprising a support frame (11) for supporting a bacterial bed (8), said bacterial bed (8) to be fixed on said carrier frame (11), as well as a ventilation ramp (6). 11. A method according to claim 10, characterized in that - the septic tank is provided with all waters (1) of a (pre) removable decolloidal filter (12) containing a removable filter net (13) located under the inspection buffer (2) closest to the outlet (4) of the effluents, and - the small circular opening (T) made on the top of the septic tank (1) has a diameter suitable for insertion and bonding in this same opening of a ventilation inlet (5) corresponding to the upper and outer part of the ventilation ramp (6). 12. The method of claim 10, characterized in that, the septic tank all waters (1) initially comprising a removable (pre) decolloidal filter (12) containing a removable filter net (13) located under the inspection pad (2). ) closest to the outlet (4) of the effluents, said (pre) removable decolloidal filter (12) is removed and the right sleeve is replaced at the tank outlet by a dip tube and, - the small circular opening (T) made on the top of the septic tank all waters (1) has a diameter adapted to allow the insertion and gluing in the same opening of a ventilation inlet (5) corresponding to the upper and outer part of the ramp of aeration (6). 13. Method according to any one of the preceding claims 10 to 12, characterized in that: - the support frame (11) is positioned horizontally and halfway in the septic tank all waters (1), - the carrier frame (11) is designed and dimensioned such that it is in contact with the inner side and front walls of the septic tank all waters (1), and - the carrier frame (11) is designed and dimensioned so that the semi-partition wall (14), lateral vertical and horizontal reinforcing ribs and frontal horizontal reinforcing ribs of the all-water septic tank (1) constitute support points for holding the support frame (11) in its horizontal position and half height.