WO1993005876A1

WO1993005876A1 - Support for liner elements consisting of the assembly of a plurality of strands, threads or filaments, and plant for treating fluid made from such supports

Info

Publication number: WO1993005876A1
Application number: PCT/FR1992/000888
Authority: WO
Inventors: Alain Christian Berganton
Original assignee: Aquaculture Et Traitement De L'eau En Armagnac
Priority date: 1991-09-26
Filing date: 1992-09-25
Publication date: 1993-04-01
Also published as: FR2681798A1; FR2681798B1; AU2762092A

Abstract

Support for liner elements (1) inserted into a rective medium for the purpose of promoting exchanges or reactions between chemical, biological and similar reagents. Each liner element consists of a plurality of strands, threads or filaments assembled in order to be freely deployed when immersed in a fluid medium. The support comprises, for each liner element, a rigid frame (3, 4) having openings provided therein, delimiting an inner volume capable of receiving the liner element (1) in its deployed state, and means (11, 12) for retaining said liner element (1) adapted to enable the latter to be deployed within the volume delimited by the frame.

Description

SUPPORT FOR TRIM ELEMENTS CONSISTING OF THE ASSEMBLY OF A PLURALITY OF STRANDS, WIRES OR FILAMENTS, AND FLUID TREATMENT INSTALLATION MADE FROM SUCH SUPPORTS.

The invention relates to a support for packing elements intended to be introduced into a reaction medium with a view to promoting exchanges or reactions between chemical, biological reagents ... brought into contact, and each consisting of the assembly of 'a plurality of strands, threads or filaments. It extends to a fluid treatment installation comprising such supports and such packing elements. At the present time, there are mainly two types of design relating to fluid installations using packing elements constituted by the assembly of strands, threads or filaments.

According to a first design, these elements are arranged in bulk, in any directions so that the strands constituting two neighboring elements are entangled. An installation produced according to this principle is described in particular in US patent. 2,229,386. The drawback of such installations lies in the fact that they do not make it possible to obtain a good compromise between a specific useful surface area for significant exchange and a low risk of clogging. In fact, any increase in the exchange surface and therefore in the potential yield leads to an increase in pressure drops and, consequently, increases the risks of clogging. The only solution to reach a satisfactory compromise actually lies in playing on the hydraulic regime. However, on the one hand, this solution is generally expensive in energy and, on the other hand, it is the source of hydraulic problems such as preferential passages ...

According to a second design, the packing elements are fixed on supports adapted to maintain them, with respect to each other, at a distance such that the strands constituting these packing elements have no risk of getting tangled. An installation according to this principle is described in particular in European patent EP 165,862 and comprises, as a support system for the lining elements, a plurality of tensioning wires arranged inside a reactor, at a distance from each other, and on which are hung these trim elements.

This solution makes it possible, thanks to the movement taken by the strands around their point of attachment, to obtain a filling having a large specific useful surface which is not likely to become clogged. It therefore resolves the drawbacks of the installations mentioned first. However, and first of all, it turns out that preferential paths are frequently created between the lines of packing elements. In addition, the implementation of the support system for such installations proves to be far too complex and costly for one to realistically envisage the production of reactors with a volume greater than a few cubic meters.

The present invention aims to overcome this drawback of installations carried out according to the principle mentioned above, and has the main objective of providing a support system for packing elements which is very easy to use and has a very low cost price allowing the realization of large volume installations.

To this end, the invention relates to a support for packing elements intended to be introduced into a reaction medium with a view to promoting exchanges or reactions between chemical, biological reagents ... brought together, and each consisting of a plurality of strands, son or filaments assembled so as to deploy freely when they are immersed in a fluid medium. According to the invention, this support is characterized in that it comprises, for each lining element:

- a rigid shell hollowed out over its larger surface and delimiting an internal volume capable of accommodating the packing element in its deployed state,

- means for retaining said packing element adapted to allow this. last to deploy within the volume delimited by the envelope.

The main objective of the invention has therefore been to produce supports, on the one hand, whose envelope has the largest vacuum index and the smallest possible exchange surface, and on the other hand, designed to to maintain the packing elements so that they are completely independent of each other.

The main advantages of such supports are that, on the one hand, they do not constitute an obstacle to transfer between the lining elements and the reaction medium, and that, on the other hand, these lining elements are individualized and can be used in bulk while keeping the principle of maintaining said packing elements at a distance from each other such that the strands of two neighboring elements do not intermingle.

The invention therefore makes it possible to produce, at low cost, installations having a large specific useful exchange surface and which are not likely to become clogged. In addition, according to this principle, the fluid flow is exploded in such a way that it cannot create preferential paths.

According to a characteristic of the invention aimed at providing an installation whose useful exchange surface is maximum, the envelope has a shape and delimits an internal volume suitable for the filling elements to fill substantially all of said internal volume, in their deployed state.

In addition, in order to minimize pressure losses and preferential passages as much as possible, each envelope preferably has a percentage of empty area greater than 90%.

Furthermore, in order to facilitate the fitting of the lining elements inside the supports, the envelope of the latter is advantageously consisting of two half-shells provided with latching means for their assembly or intended to be assembled by heat welding. Such a support is thus particularly suitable for housing packing elements with very high specific surface, as described in patent EP 165,862, and comprising a plurality of strands, threads or filaments joined in their middle so as to form a pompom. According to the invention, the envelope then preferably has a spherical shape, and the holding means are adapted to hold a lining element so that the meeting point of the strands, son or filaments is located in the center of the 'envelope. In this case, moreover, the holding means preferably comprise an internal candle extending orthogonally to the envelope and having a length substantially equal to the radius of said envelope, said candle having a free end provided with means for holding a packing element.

The free end of this candle can thus have a longitudinal slot capable of accommodating the meeting point of a lining element, the holding means being adapted to wedge said filling element in said slot.

In addition, according to another characteristic of the invention, the envelope is then advantageously made up of two half-shells of identical semi-spherical shape, the candle being provided with one end, opposite its free end, provided with a longitudinal hole suitable for allowing the attachment of said candle to a half-shell by means of a fixing element.

According to a variant, it can be envisaged to integrate the candle into one of the two half-shells during the molding of the latter.

The invention also extends to a fluid treatment installation of the type comprising an enclosure provided with means for supplying fluid and evacuation means after treatment, and packing elements arranged inside the enclosure and each consisting of a plurality of strands, son or filaments assembled so as to deploy freely when said enclosure is filled with fluid.

This installation is characterized in that each lining element is disposed inside a support comprising: - a rigid envelope hollowed out over its largest surface and delimiting an internal volume capable of housing the lining element in its deployed state ,

means for holding said lining element adapted to allow the latter to deploy inside the volume delimited by the envelope,

- Said supports being arranged in bulk in the enclosure so as to be independent of each other and to come into contact with each other by their envelope. Other characteristics, objects and advantages of the invention will emerge from the detailed description which follows, with reference to the appended drawings which show by way of nonlimiting example a preferred embodiment. On these drawings which form an integral part of this description:

FIG. 1 is a perspective view, in exploded mode, of a support and of a packing element according to the invention,

FIG. 2 is a longitudinal section of this support containing a packing element in the deployed state,

- Figure 3 is a schematic section of one of the possible configurations of fluid treatment installation equipped with supports according to the invention.

The support shown in Figures 1 and 2 is intended to individually accommodate a packing element 1 held inside this support so that it can deploy freely. This packing element 1, shown in FIG. 1 which is not deployed, is a pompom as described in European patent EP 165,862. It is made up of a plurality of strands, threads or filaments joined in their middle and assembled at this point by means of a ring 2.

Each of the supports intended to house these pompoms 1 comprises, first of all, two strictly identical half-shells 3 _. 4 of semi-spherical shape. These half-shells 3, 4 are provided with latching means 5, 6 making it possible to assemble them so that they form a spherical envelope delimiting an internal volume equivalent to the volume of a pompon 1 in its deployed state. In the example, each spherical envelope thus has a diameter of sixteen centimeters.

First, each half-shell 3, 4 is composed of arcs such as 7 extending along meridians uniformly distributed around the axis of revolution. These arcs 7, eight in number, further form, at the pole of the half-shell 3 _ι 4, a small circular cap 8, for example three centimeters in diameter, pierced with an orifice 8a.

Each half-shell 3, 4 further comprises a hoop 9 forming a large circle connecting the end of the arcs 7 and carrying the latching means 5, 6. In addition, an intermediate hoop 10 for reinforcement also connects the arcs 7 away from their ends.

Thus formed, such half-shells 3, 4 are provided with a surface having a very high percentage of vacuum, greater than 90%.

The latching means of these two half-shells are made up of male 6 and female 5 organs arranged in conjugate positions on the hoops 9 so that a male organ 6 of a half-shell (3 or 4) corresponds to a female member 5 of the other half-shell (4 or

3).

The female organs consist of a slide 5 formed on the external face of the hoop 9. These slides 5 are two in number per half-shells 3 _. 4 and are arranged to be diametrically opposed.

The male members consist of a locking ring 6 adapted to snap into a slide 5 so as to bring the hoops 9 of the half-shells 3, 4 to ^'contact one another. These heels 6 are also two in number per half-shells 3, 4 and are arranged so as to be diametrically opposite, according to a diameter orthogonal to the diameter connecting the slides 5.

Secondly, each support comprises means for holding the pompom 1 capable of maintaining the meeting point of the strands of this pompom positioned at the center of the spherical envelope, after assembly of the half-shells 3, 4.

These holding means consist of a candle 11 of length substantially greater than that of the radius of the sphere comprising, firstly, a hollow tubular rod 12 split longitudinally and over a given length from one of its ends 12a. This rod 12 also has an opposite end 12b flared outwardly.

- This candle further comprises a first sleeve 13 adapted to abut against the flared end 12b of the rod 12 and to house the latter over a length corresponding substantially to its unsplit length. It finally comprises a second sleeve 14 capable of accommodating the rod 12 over a length of the latter substantially less than its split length. Such a candle 11 makes it possible to maintain a pompom 1 housed in the slot 12a of the rod 12 by wedging the latter between the two sleeves 13, 14, the longitudinal locking of the second sleeve 14 being ensured, for example, by thermo-deformation of the end of said sleeve and of the rod.

This candle 11 has the advantage of leaving a maximum internal volume of the support free of obstacles opposing the deployment of the pompom 1. It also has the advantage of being able to be introduced in the support once the half-shells 3 _> 4 are assembled, its fixing then being ensured by means of a simple screw 15 housed in the orifice 8a of one of said half-shells. The main advantage of the supports described above resides in the fact that they can be introduced in bulk into a reactor, thus making the production of large reactors easily accessible. FIG. 3 schematically represents such a reactor of the bottom feed type and overflow discharge.

This reactor conventionally comprises a closed enclosure 16 comprising a perforated intermediate floor 17, supply means 18 disposed under the perforated floor of the enclosure, and consisting of a pipe pierced, for example in the shape of a star, and an outlet d 'evacuation 19 disposed in the upper part of the enclosure.

This enclosure 16 is filled over a given height above the floor 17 with a plurality of supports 3, 4 arranged in bulk, each containing a pompon 1 and adapted so that said pompoms can deploy freely without coming to become entangled so occupy the maximum volume of the enclosure and thus provide a maximum specific exchange surface.

This enclosure further comprises a perforated floor 20 disposed in the upper part above the last layer of supports 3, 4. This floor 20 is intended to trap all of the supports in the reaction medium.

Finally, it includes a recirculation loop 21 provided with a pump 22, intended to collect the effluent in the upper part of the enclosure 16, just below the level of the discharge outlet 19, and to reinject the latter. in the lower part of the enclosure 16 by means of a distribution ramp 23. Such a recirculation loop 21 has, conventionally, the role of diluting the effluent as it enters the reactor.

In addition to the aforementioned advantages of such installation, an additional advantage arises from the fact that a mud bed tends to form under the perforated floor. Such a mud bed constitutes, in fact, a reserve of bacteria often different from those settling on the pompoms, in which the flow will bubble at the start.

It should be noted that it is similarly possible to produce with this type of packing elements installations with vertical downflow and horizontal flow.

With regard to the specific applications and advantages of pompons 1 thus kept at a distance from one another, it is in particular advisable to refer to patent EP 165,862.

Claims

CLAIMS 1 / - Support for packing elements (1) intended to be introduced into a reaction medium with a view to promoting exchanges or reactions between chemical, biological reagents ... brought into contact, and each consisting of a plurality strands, son or filaments assembled so as to deploy freely when they are immersed in a fluid medium, said support being characterized in that it comprises, for each lining element:

- a rigid envelope (3, 4) hollowed out over its larger surface and delimiting an internal volume capable of accommodating the lining element (1) in its deployed state, - holding means (11-15) of said lining element (1) adapted to allow the latter to deploy inside the volume delimited by the envelope (3, 4).

2 / - Support according to claim 1, characterized in that the envelope (3, 4) has a shape and defines an internal volume adapted so that the filling elements (1) fill substantially all of said internal volume, in their state deployed.

3 / - Support according to one of claims 1 or 2, characterized in that the envelope (3, 4) has a percentage of empty area greater than 90%.

4 / - Support according to one of claims 1 to 3, characterized in that the envelope (1) consists of two half-shells (3, 4) provided with latching means (5, 6) for their assembly.

5 / - Support according to one of claims 1 to 4 for packing elements each consisting of a plurality of strands, son or filaments joined in their middle so as to form a pompom (1), characterized in that the envelope (3, 4) has a spherical shape, and the holding means (11-15) are adapted to hold the pompom (1) so that the meeting point of the strands, threads or filaments is located in the center of the envelope.

6 / - Support according to claim 5, characterized in that the holding means comprise an internal candle 11 extending o thogona the m at t to the envelope (3, 4) and having a length substantially equal to the radius of said envelope, said candle (11) having a free end (12a) provided with holding means (13, 14) of a packing element (1).

7 / - Support according to claim 6, characterized in that the free end of the candle (11) has a longitudinal slot (12a) adapted to accommodate the meeting point of a packing element (1), the means of maintaining _(13. 1 * 0 being adapted for clamping said packing member into said slot.

8 / - Support according to claims 4 and 7 taken together, characterized in that the envelope consists of two half-shells (3, 4) of identical semi-spherical shapes, the candle (11) being provided with one end (12b), opposite its free end (12a), provided with a longitudinal hole able to allow the fixing of said candle to a half-shell (3, 4) by means of a fixing element (15).

9 / - Support according to claim 8, characterized in that each half-shell (3, 4) comprises arcs (7) extending along meridians uniformly distributed around the axis of revolution, and a hoop (9) forming a large circle connecting the end of said arcs and carrying the latching means (5, 6).

10 / - Support according to claim 9, characterized in that the latching means comprise male (6) and female (5) organs arranged in conjugate positions on each of the half-shells (3, 4) so that a male member (6) of a half-shell (3 or 4) corresponds to a female member (5) of the other half-shell (4 or 3), each female member consisting of a slide (5) provided on the external face of the hoop (9), and each male member consisting of a snap-on heel (6) capable of snapping into a slide (5).

11 / - Fluid treatment installation of the type comprising an enclosure (16) provided with means fluid supply (18) and evacuation means (19) after treatment, and packing elements (1) arranged inside the enclosure (16) and each consisting of a plurality of strands, wires or filaments assembled so as to unfold freely when said enclosure is filled with fluid, said installation being characterized in that each lining element (1) is disposed inside a support comprising: - a rigid envelope (3, 4) hollowed out over its largest surface and delimiting an internal volume capable of housing the lining element (1) in its deployed state,

- holding means (11-15) of said lining element (1) adapted to allow the latter to deploy inside the volume delimited by the envelope (3, 4),

- Said supports being arranged in bulk in the enclosure (16) so as to be independent of each other, and to come into contact with each other by their envelope (3, 4).