EP2184148B1 - Compartmentalised tank - Google Patents

Description

Technical area

The present invention relates to a compartmentalization method for tanks and compartmentalized tanks used in particular in the field of purification plants.

State of the art

The purification of domestic water can be carried out through purification plants which generally comprise several tanks or compartments. The water passes successively through the compartments each integrating a different function, for example the degreasing of water, microbiological degradation, decantation, etc.

The treatment plants are usually made from a standard concrete or plastic tank on the market, which is adapted by first installing each of the concrete or synthetic bulkheads separating the different compartments. The various partitions must then be fixed in the tank and the installation of seals is necessary in order to obtain a seal between the different compartments. An example of tanks of this type is described in EP 1 719 738 A1 . This sealing is all the more important as the differential pressures exerted on the partitions are high.

This realization of treatment plant is relatively long because the operator must first lock the various partitions in the tank, and once set proceed to the installation of joints. In addition, the operator exposes himself to risks when he enters the tank to fix the partitions, because the partitions can be overturned on him, which is all the more dangerous in the case of heavy partitions. (concrete for example).

To avoid this risk, one could consider inserting the partitions in U-shaped grooves in the wall of the tank. Nevertheless, it has been found that such a configuration is not sufficiently tight because of the manufacturing tolerances that are to be considered, and the installation of seals therefore still remains necessary.

These disadvantages could be overcome by molding tanks compartmentalized in one piece, the tanks and compartmentalizing partitions thus being formed of a single material. An example of this type of tank is described in WO 97/00833 A1 . They could be transported as such to the customer, possibly requiring the installation of additional elements, such as a biological reactor cassette. With this type of tank, the shapes that can be given to the tank are however limited by the molding technique. Similarly, it is not easy for example to position orifices in the middle of a partition. It would therefore be necessary to perform additional operations, for example holes, where the operator must descend into the tank after molding. In the case of concrete, it is then advisable to wait until the concrete of the molded tank is sufficiently taken in order not to damage the still fresh tank, which lengthens the manufacturing time. Nevertheless, the major disadvantage remains the weight of these compartmentalized tanks, especially if they are molded in concrete or other heavy materials. Indeed, their weight increases rapidly with the number of partitions provided, the installation of such tanks therefore requires heavy construction equipment, which is not always desirable or possible.

Object of the invention

The object of the present invention is therefore to provide a compartmentalized vessel with a reduced weight, while being waterproof. In addition, the equipment of these tanks to turn them into a treatment plant should be easy and fast, with the least risk of accidents for the operator.

General description of the invention

In order to solve the problem mentioned above, the present invention relates to a compartmentalized molded vessel having a bottom and peripheral walls. This tank also comprises one or more partitions of fine and / or light material whose edges are sealed by molding in the wall and the bottom of the tank, so as to obtain a perfect seal between the compartments. The bottom and the peripheral wall are made of concrete and / or fiber cement and the partition (s) made of fine and / or light material are made of stainless steel and / or of a rotproof synthetic material.

The invention has three major advantages: the first is to have a compartmentalized vessel, the edges of the partitions are embedded in the tank during molding, so as to obtain an almost perfect seal, both between the wall of the tank and the partitions and between the bottom of the tank and the partitions.

The second advantage, just as important, is that the invention by molding sealing allows the use of thinner partitions, which considerably reduces the weight of the compartmentalized tanks and therefore the costs of transportation and installation.

Third, the insertion of partitions directly during molding does not significantly increase the manufacture of the tank, but make superfluous their subsequent installation in the workshop or at the customer. Indeed, as the tank is molded with the partitions inserted, this results in a lighter and ready-to-use compartmentalized tank that can be delivered directly to the customer by the tank manufacturer. The use of fixing means and the descent of operators in the tank to ensure the attachment are also superfluous, thus improving safety.

Finally, the interest of the invention lies in the simplicity and speed of assembly, which is obviously interesting from an economic point of view.

The compartmentalized tanks, that is to say the peripheral wall and the bottom, are molded of concrete and / or fiber cement. On the other hand, if necessary, suitable additives may be added such as, for example, stiffening compounds, fibers, setting accelerators, water repellents, polymeric resins or combinations thereof.

As indicated, in order to overcome the problem of compartmentalized tanks, the partitions used are lightweight partitions compared to concrete walls. For this, they are made of thin and / or light material, that is to say they can be made of a relatively heavy material, but then having a reduced thickness (and thus forming light partitions), such as for example stainless steel partitions, or the material used is fine and light, such as rot-proof synthetic materials such as PVC, high-density polyethylene, polyethylene, polyester, polypropylene, nylon or any other material adapted. It is also possible to use foamed materials which are light but which then present generally a larger thickness. All combinations of these materials are also possible. The thickness of the material used obviously depends on the material used and the stresses provided, however, it will normally be between 1 mm and 3 cm, preferably between 2 mm and 2 cm.

The reduced weight of such a tank thus facilitates its transport and installation at the customer. Indeed, in practice one can achieve a significant weight gain, for example of the order of several hundred kilograms for a standard purification tank, this weight gain obviously dependent on the size of the compartmentalized vessel and the number of compartments provided.

By providing suitable stiffening means, such as grooves, grooves, etc., it is also possible to further reduce the weight of the tank because these means allow to use even thinner walls or even lighter material .

This reduction in weight ultimately allows easier handling compartmentalized tanks and can for example get rid of large construction equipment to install the tank at the customer.

Partitions of fine material according to the invention can take any form suitable for use such as straight, curved, corrugated, etc. The edges of the partitions may be continuous with the remainder of the partition, that is to say have a shape (or section) substantially identical to the rest of the partition. Thus, it is possible to use, for example, a substantially straight partition whose edges are also substantially straight (sharp edges). Nevertheless, the edges may take any other form suitable for use. When the existing pressures on either side of the compartments are similar, that is to say the differential pressure is low, partitions of fine material with straight edges for example are rigid enough to ensure a perfect seal.

Perfect or near perfect sealing means a seal between the partitions and the wall of the tank which is sufficient so that the liquid contained in a compartment does not flow significantly between the partitions and the bottom or the wall of the tank. the tank, and this both in the presence of low differential pressures (eg same level of liquid in the compartments), as in the presence of high differential pressures (which may already occur by example of the emptying or filling of a compartment). It is clear that this configuration does not exclude the passage of liquids through holes, notches, orifices, etc. specially designed for this purpose and for the intended use, such as in the case of a wastewater treatment plant.
In the event that significant differential pressures are exerted on the partitions, a partition, such as a right-sided straight partition sealed in the tank could bend, dislodge and thus no longer ensure tightness between the compartments. Indeed, the compartmentalized tanks according to the invention generally have a chemical incompatibility between the material used for the molding of the tank and that of the partition, so that there is generally no sufficient chemical bond between the two materials, unlike compartmentalized tanks molded in one piece with identical material.

Therefore, to avoid possible dislocation of partition (s) under high pressure, an advantageous embodiment of the present invention proposes to use partitions whose edges sealed in the tank have one or more means of anchoring or blocking mechanical. These anchoring means may be arranged regularly or not, that is to say they can be all around the useful periphery of the sealed partition in the tank, or only a part.

By means of anchoring means any means or tool for blocking the partition in the wall and the bottom of the tank, that is to say perform a mechanical blockage which withstands even high forces and thus prevents dislocation or tearing the edge of the partition out of the wall and / or the bottom of the tank. These forces come for example from pressure differences existing for example during filling or emptying, where one of the compartments can be filled with liquid, while the other is still / already empty.

Advantageously, the edges sealed by molding thus have anchoring means in the form of sealing profiles in the form of a dovetail, pear-shaped, T-shaped, etc. The anchoring edges may be present evenly over the entire edge or they may for example only be placed in places under heavy forces and therefore requiring a stronger grip, for example on the upper part of the partition.

The blocking can also be obtained by attaching accessories to / in the edges of the partition, such as for example rods attached to the partition which during molding are integrated and the wall and / or the bottom of the tank.

Different anchoring means can obviously be provided in combination on the same edge and / or on the same partition.

The skilled person is aware that it is necessary to adapt the sealing depth of the edges of the partitions in the wall and / or the bottom of the tank according to the intended use. The thickness of the wall and the bottom of the tank and the partitions will depend in particular on the nature of the material used and the rigidity of the compartmentalization desired or necessary. The skilled person will also easily determine how deep must seal the edge of the partition to achieve an effective seal without weakening the tank. Thus in practice, the width of the sealed edge, that is to say the depth to which the partition is sealed in the wall and / or the bottom of the tank is of the order of one to several centimeters, in general from 2 to 5 cm.

It is clear that, in principle, the sealing of the edges of the partitions in the wall and / or the bottom of the tank according to the invention reduces a priori the effective thickness of the wall and / or the bottom at the location of the seal .

In the case where this aspect would be critical, a particular embodiment of the present invention provides the molding of thicknesses on the inner face of the wall and / or the bottom of the tank, where the edges of the partitions of fine material are sealed. by molding. Moreover, the skilled person can also add extra thicknesses on the outside of the bottom of the tank and / or the wall if necessary.

Another means of obtaining an anchoring and mechanical locking effect which at the same time makes it possible to reduce the effect of reducing the effective thickness at the sealing locations can be obtained for example by producing perforations or holes on the lateral edges of the partitions. These perforations or holes are filled during the molding of the tank and thus form an anchoring while increasing the effective thickness of the wall or bottom at the sealing location of the partitions. The size, shape and number of these holes is in principle not critical, but is generally determined in part by the material used for the bulkhead and / or for the molding of the vessel.

It is clear that these various elements and measures anchoring, stiffening and increasing the effective thickness of the wall and / or the bottom can be combined if deemed useful.

In a particular embodiment, the partition (s) to be sealed in the tank is (are) chosen from simple, complex and / or integrated partitions.

A partition made of thin material in the sense of the present invention is, in its most basic embodiment, a simple partition having two lateral edges and a lower horizontal edge, these edges being in continuity.

In another advantageous variant of the invention, the partition may also form a so-called integrated partition. Integrated wall means a partition which integrates at least one compartment. This integrated partition further has a bottom and the bottom carrying the lower horizontal edge which is sealed in the bottom of the tank. Thus the integrated partition, like the simple partition, has edges in continuity. The advantage of the integrated partition is that at least three compartments are obtained with the sealing of a single partition. In addition, the partition is sealed in two places in the wall (in addition to the seal in the bottom), which has the potential advantage of weakening the vessel less. The integrated partition may furthermore integrate more than one compartment, these compartments being able to take various forms, for example rectangular, triangular, etc., the essential being that the molding of the compartmentalized vessel is feasible. As for the single wall, the material used for the integrated partition has a reduced thickness compared for example to concrete.

In another advantageous variant of the invention, the partition may be a so-called complex partition, that is to say having more than two lateral edges, for example a partition whose base is in the form of a cross, a star, etc. This complex partition also has a bottom, the bottom bearing the sealing edge that will be crimped into the bottom of the tank. The advantage of the complex partition is that at least three compartments are obtained with a single partition. In addition, this complex partition can be assembled beforehand in the workshop and avoids having to assemble various simple partitions to obtain a complex partitioning at within the tank. It is clear that a tank can accommodate the different types of partitions (simple, complex and integrated).

The partitions may furthermore have notches, incisions, holes, holes or any other appropriate form, to allow for example the flow of liquid through the various compartments or ventilation.

The partition may be straight, but the person skilled in the art can of course adapt it according to the use of the tank to give it various shapes, for example a curved, wavy shape, etc. and the partition may also be reinforced by grooves, grooves or any other suitable reinforcing means. It is also possible to increase the rigidity of the compartmentalized vessel by known means, for example by the application of splines and other structures, by the mounting of reinforcing profiles, etc.

The invention thus allows to have partitions sealed in the tank, that is to say, sealed but also locked in position. In this way, the molded compartmentalized tank can, once demolded and sufficiently hardened concrete, be delivered directly to the customer, the fixing of partitions or the installation of joints being superfluous.

In an advantageous embodiment of the invention, the complex partition and / or the integrated partition form a cassette, that is to say a pre-equipped module for carrying out particular functions in a compartment. It may for example be a biological reactor cassette forming a compartment for biological degradation, composed for example of a complex or integrated partition as described above, equipped with a support for microorganisms, an aeration system and / or a bubbling system. The cassette may also form a settling cassette forming a compartment for settling, composed of one of the partitions described above equipped with an inclined plane for example to facilitate settling.

Different variants of biological reactor cassettes are possible, the essential being that it is possible to seal their edges in the wall and / or the bottom of the tank during molding of the latter, without damaging the function or functions provided, for example the biological bed. In practice, the cassettes must therefore have a bottom if the molding is carried out with inverted tank (see below). The support of the bed can take different forms, for example tubular, spherical, conical, etc. It should be noted, however, that the shape of the biological reactor cassette is critical only in the sense that it must be suitable for the intended use, and that it must allow, by its shape and its dimensions, the compartmentalisation of a tank of determined size and shape. The compartments of a tank can thus be formed of partitions and or cassettes.

In this way, the assembly of a sewage treatment plant is easy and fast. This biological reactor cassette is prefabricated in the workshop. It is then sealed in a tank during the molding thereof and the compartmented tank can then be delivered directly to the customer. On-site installation is faster and requires less heavy equipment.

A further aspect of the present invention relates to a wastewater treatment plant comprising a molded compartmentalized tank as described above.

Advantageously, the compartmentalized tank as defined above can be used for the treatment of wastewater.

Thus, it has a purification plant simple assembly, fast and inexpensive. By using a pre-assembled biological reactor cassette, the transformation into a purification plant is all the more simple and fast. It can also withstand high differential pressures because of the edges crimped into the tank. Finally, because of its reduced weight, the handling of this tank is greatly facilitated.

1. a) de prévoir un moule extérieur déterminant la forme et les dimensions extérieures de la paroi et du fond de la cuve,
2. b) de prévoir un moule intérieur, divisé à des endroits prévus pour accueillir une ou plusieurs cloisons en matériau fin,
3. c) de placer une ou plusieurs cloisons en matériau fin aux endroits définis ci-dessus du moule intérieur divisé, les bords des cloisons faisant saillie par rapport aux limites extérieures du moule intérieur,
4. d) de placer le moule intérieur et les cloisons à l'intérieur du moule extérieur, les bords faisant saillie (par exemple le profil de scellement) se trouvant dans l'espace qui formera la paroi et/ou le fond de la cuve moulée,
5. e) de mouler la cuve par remplissage de cet espace avec scellement des bords des cloisons dans la paroi et/ou le fond de la cuve.

Finally, the present invention relates to a compartmentalization method for molding compartmentalized tanks. This method includes the steps:

1. a) providing an outer mold determining the shape and external dimensions of the wall and bottom of the tank,
2. b) to provide an inner mold, divided in places intended to accommodate one or more partitions of fine material,
3. c) placing one or more partitions of fine material at the above defined locations of the divided interior mold, the edges of the partitions projecting from the outer boundaries of the inner mold,
4. d) placing the inner mold and the partitions inside the outer mold, the protruding edges (for example the sealing profile) being in the space which will form the wall and / or the bottom of the molded vessel,
5. e) mold the tank by filling this space with sealing edges of the partitions in the wall and / or the bottom of the tank.

The molding can be carried out in any suitable manner, but is preferably carried out with an inverted tank, ie the tank is molded with the bottom at the top. After molding, the assembly is turned over and then the outer and inner molds are removed.

The demolding may be carried out, for example, off-line or in full, but preferably it is carried out in full. Integral mold release means that the molding is followed immediately by demolding. This technique can be used, for example, for concrete: the fresh concrete vat with walls sealed in the resulting vat is dried and ready for delivery. Thus, the mold used is quickly reusable, which reduces the number of molds required and has an economic advantage. Another advantage of the invention is that the partition (s) thus sealed in the wall of the vessel reinforce it during demolding and during the entire drying period, thus avoiding, for example, deformations of the peripheral wall. of the tank.

Advantageously, the inner molds and the partitions inserted into the outer mold have a substantially conical shape narrowing towards the bottom of the mold. Indeed, in the case of molding concrete tanks, milt could be introduced for example between the inner molds and partitions and solidifying, it could prevent or at least interfere with the demolding. By using interior molds and / or bulkheads of substantially conical shape as indicated, this possible disadvantage can be overcome. The narrowing between the top and bottom of the inserted partition, respectively of the inner mold, is in the range of 0.5 ° to 4 °, preferably 1 ° to 2 °. The skilled person will know that in this case, the tank, after turning and demolding, has walls and / or partitions whose cross section is substantially narrower at the top of the partition at the bottom of the partition.

Suitable release agents can also be used to facilitate demolding. It is also clear that the anchoring means described above also generally increase the holding of the partitions during demolding, even at fresh (integral demolding), thereby reducing the risk of tearing of the partitions during demolding.

Brief description of the drawings

• Fig. 1 : Vue d'une partie de cuve selon l'invention, montrant une cloison en matériau fin dans une cuve moulée
• Fig. 2 : Section de différentes formes de réalisation de profils de bord de cloison, (A) franc, (B), (C) et (D) à ancrage.
• Fig. 3 : Vue de profil d'une cloison intégrée selon un mode particulier de l'invention.
• Fig. 4 : Vue d'une cloison intégrée selon un mode particulier de l'invention.

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:

• Fig. 1 : View of a tank portion according to the invention, showing a partition of fine material in a molded tank
• Fig. 2 : Section of various forms of partition edge profiles, (A) frank, (B), (C) and (D) anchored.
• Fig. 3 : Side view of an integrated partition according to a particular embodiment of the invention.
• Fig. 4 : View of an integrated partition according to a particular embodiment of the invention.

Description of preferred embodiments

The figure 1 has a bowl portion 10 comprising a peripheral wall 105 and a bottom (not shown). The tank 10 is compartmentalized by a partition 100 having a dovetailed anchor edge 101 sealed in the wall 105 during molding.

The figure 2 presents some particular forms of edges 201 of partitions. A substantially straight partition 200 (A) has a frank lateral edge in continuity of the partition, this edge may be sealed for example in a tank where differential pressures are exerted on the walls, without risk of dislocation. On the other hand, if larger pressure differences are to be expected, partitions with an anchored edge such as dovetail (B) and (C) or cylindrical (D), are preferable to block the partition in the tank and to ensure sealing.

The figure 3 presents an embodiment of the present invention showing in profile an integrated partition 300 having side and bottom edges 301, said edges being sealed in the wall and the bottom of a vessel (not shown). In this particular embodiment of the invention, the partition has a substantially narrower cross section at the top of the partition than at the bottom of the partition.

The figure 4 discloses an embodiment of the present invention showing a cassette integral partition 403 having two side edges and a lower edge 401, these edges being continuous. This cassette may have stiffening means, such as grooves 404. It is also possible to fix different accessories, such as for example a biological bed (not shown) in this cassette with rods of appropriate material, these rods would end in the grooves 404 and do not interfere with the molding of the tank.

Claims (14)

1. Moulded compartmentalised tank with a bottom and a peripheral wall and comprising one or a plurality of partitions made of fine and/or light material whose edges are sealed by moulding in the wall and the bottom of said tank to obtain a perfect seal between the compartments, in which the bottom and the peripheral wall are made of concrete and/or fibrocement and in which the partition(s) made of fine and/or light material are manufactured from stainless steel and/or a synthetic, rot proof material.
2. Compartmentalised tank according to claim 1, characterised in that the edges sealed by moulding in the wall and/or in the bottom have one or a plurality of anchoring means.
3. Compartmentalised tank according to claim 2, characterised in that the anchoring means has/have a dovetail shaped section, pear shaped section, T-shaped section or combinations of these.
4. Compartmentalised tank according to claim 2 or 3, characterised In that the anchoring means is/are formed by perforations.
5. Compartmentalised tank according to any ane of the previous claims, characterised in that the wall and/or the bottom of the tank moreover have extra thicknesses on their inner surface at the places where the edges of said partitions made of fine material are sealed by moulding.
6. Compartmentalised tank according to any one of the previous claims, characterised in that the wall and/or the partition(s) have a vertical conical section that is wider at the side of the bottom of the tank.
7. Compartmentalised tank according to any one of the previous claims, characterised in that the bottom and the peripheral wall made of concrete and/or of fibrocement comprise other materials, such as fibres, setting accelerators, waterproofing agents, polymeric resins; or combinations thereof.
8. Compartmentalised tank according to any one of the previous claims, characterised in that the rot proof synthetic material is selected from PVC, high density polyethylene, polyethylene, polyester, polypropylene; or combinations thereof.
9. Compartmentalised tank according to any one of the previous claims, characterised in that the partition(s) made of fine and/or light material is (are) selected from simple partitions, complex partitions having more than two lateral edges and/or integrated partitions integrating at least one compartment.
10. Compartmentalised tank according to claim 9, characterised in that the complex and/or integrated partition(s) form(s) a cassette that is a pre-equipped module for carrying out specific functions in a compartment, preferably a bioreactor cassette forming a compartment for biological degradation equipped with a support for microorganisms, a ventilation system and/or a bubbling system, or another cassette for decantation forming a decantation compartment, consisting of one of the above partitions equipped with an inclined plane.
11. Method for compartmentalising moulded tanks having a bottom and a peripheral wall, said method comprising the steps:

    a) providing an external mould that determines the shape and the external dimensions of the wall and the bottom of the tank,

    b) providing an inner mould, divided at the locations foreseen for receiving one or a plurality of partitions made of fine and/or light material,

    c) placing one or a plurality of partitions made of fine and/or light material at said locations of the divided inner mould, wherein the edges of said partitions are protruding.

    d) placing said inner mould and said partitions inside the external mould, wherein the protruding edges are positioned in the space that will form the wall and the bottom of the moulded tank,

    e) moulding the tank by filling this space and sealing the edges of the partitions in the wall and the bottom of the tank,

    in which the bottom and the peripheral wall are in concrete and/or fibrocement and wherein the partition(s) made of fine and/or light material are manufactured from stainless steel and/or a rot proof synthetic material.
12. Method for compartmentalising tanks according to claim 11, characterised In that the wall and/or the partltion(s) have a vertical conical section that is wider at the side of the bottom of the tank.
13. Waste water purification system comprising a compartmentalised tank according to any one of claims 1 to 10.
14. Use of a compartmentalised tank according to claims 1 to 10 for treating waste water.

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