WO2021019132A1

WO2021019132A1 - Filtration device for a controlled-atmosphere installation, corresponding installation and corresponding implementation method

Info

Publication number: WO2021019132A1
Application number: PCT/FR2020/000214
Authority: WO
Inventors: John Mumford; Guillaume RIBOT
Original assignee: Shield
Priority date: 2019-07-30
Filing date: 2020-07-29
Publication date: 2021-02-04
Also published as: FR3099380B1; FR3099380A1

Abstract

This filtration device (1) comprises a body (2), at least one filter (3), at least one sleeve (4), and also means (25, 26, 27, 28) able to fix a first end (42) of the sleeve to the body in a sealed manner. The second, open end (43) of the sleeve defines a periphery (44) able to be secured in a sealed manner to a connecting member (6) intended to cooperate with the inlet or outlet pipe of the installation. The invention, which provides for use to be made of a sleeve fixed in a sealed manner to the walls of the filter, makes it possible to overcome the inopportune presence of the air passage intervals that are observed in the prior art. The contaminated air does not bypass the replacement filter during the removal of the used filter and then during the fitting of the replacement filter. The invention therefore allows a truly secure method by contrast with the prior art.

Description

FILTRATION DEVICE FOR INSTALLATION WITH A CONTROLLED ATMOSPHERE, INSTALLATION AND PROCESS FOR IMPLEMENTATION

CORRESPONDENTS

Technical field of the invention

The present invention relates firstly to a filtration device intended to equip a controlled atmosphere installation. The subject of the invention is also such a controlled atmosphere installation, which is equipped with at least one such filtration device. The invention further relates to a method, allowing the implementation of this installation.

The invention relates to any type of controlled atmosphere installation, which uses at least one device for filtering the gases, in particular air, flowing through this installation. In general, such an installation comprises a so-called working cell, means for admitting gases into this cell, as well as means for discharging these gases from this cell.

According to a first main variant of the invention, the work cell is a containment cell, which is provided with at least one wall forming a delimitation between two spaces, which are advantageously mutually hermetic. This confinement can be of the biological type intended for the care of infected patients, presenting a high epidemic risk. It also finds its application in other types of containment, in particular the handling of radioactive products in the nuclear industry or of toxic products in the chemical and pharmaceutical industry. The aforementioned spaces first include an outdoor, unconfined space. The other space, called confined, must be isolated as absolutely as possible from the aforementioned external space. In the case of biological containment, the patient to be treated is received within this confined space.

In service, it is necessary to ventilate the containment cell, either continuously or periodically. It can be understood that the air circulating in the confined space of the containment cell is subject to contamination. It is therefore necessary to evacuate this stale air, then to filter it in a downstream filtration device, before rejecting it in complete safety. In some types of containment installation, it is also necessary to perform upstream filtration. In other words, the air admitted into the containment cell is subjected to prior passage through an additional filtration device. In this first variant, the circulation of gases can be put in works equally well in blowing or extraction mode, namely a fan placed in the respectively upstream or downstream part of the installation.

According to a second main variant of the invention, the work cell is a cell where the atmosphere must be of very high purity. This is typically a so-called clean room application. In this case, the air admitted into this white cell is subjected to prior filtration, within a filtration device placed upstream of this cell. As in the first variant, the circulation of gases in this second variant can be carried out either in blowing or extraction mode.

State of the art

Filtration devices are already known, in particular for containment installations, using a THE (Very High Efficiency) type particle filter which is typically placed in a box. As a variant, also covered by the invention, it is also possible to use carbon filters. The aforementioned box has an entrance, placed in communication with the containment by a pipe placed respectively upstream or downstream, depending on whether it is operating in blowing or extraction mode. Opposite this inlet, an outlet of the box allows the evacuation of the air thus filtered, via a downstream or upstream pipe, respectively. The box is also equipped with a side door allowing access to the interior volume of the box, in order to remove the used filter. The latter is then subjected to an operation, generally aimed at destroying it. In certain specific situations, in particular in the case of biological containment, it is possible to decontaminate this used filter inside the chamber itself.

A known solution involves a process called BIBO ("bag in, bag out"), according to which a flexible bag is used allowing the extraction of the used filter. Essentially, the open end of the bag is first attached to a collar, which is mounted around the periphery of the opening defined by the access door mentioned above. The used filter is then withdrawn from the box, so as to be admitted into the interior volume of the bag. The latter is then tightened and cut, so as to define, on the one hand, a closed pocket containing the used filter and, on the other hand, an equally closed end piece extending from the access door. Secondly, we position a new filter, received in another bag, next to the nozzle. This bag is then connected to the nozzle, then is opened to place the new filter in the box.

This known process, however, involves certain drawbacks. Indeed, it was firstly observed that it does not have sufficient reliability in terms of harmlessness. In particular, when a new filter is put back into service, contaminated air flows into an area where in theory only purified air should be present. This drawback could possibly be solved by decontaminating this air in the filter. However, as mentioned above, such decontamination is only possible in specific situations. It is therefore understood that the untimely presence of this contaminated air is likely to generate pollution, potentially dangerous for the environment.

Furthermore, this process is accompanied by a drawback in terms of handling by the operators. The latter can, in particular, be subject to musculoskeletal disorders. In addition, there is a risk of personnel exposure, following any damage to the bag mentioned above. Indeed, this bag is subject to tears, even to untimely tearing. This phenomenon is particularly related to the fact that the filter has a significant weight, as well as an aggressive mechanical structure, in particular protruding edges.

Finally, in this known process, the bag replacement operation requires a long time to complete. This therefore entails significant associated costs, notably linked to prolonged ventilation shutdown, as well as labor costs.

In view of the above, an objective of the present invention is to remedy, at least partially, the drawbacks of the prior art mentioned above.

Another object of the invention is to provide a filtration device which prevents any flow of contaminated air to the outside during the replacement of the filter.

Another object of the invention is to provide such a filtration device, which easily and quickly lends itself to replacement operations.

Another objective of the invention is to provide such a filtration device, which has a lower cost price than that of the solutions known from the state of the art. Objects of the invention

According to the invention, at least one of the above objectives is achieved by means of a filtration device for a controlled atmosphere installation (101; 301), said installation comprising a working cell (110), an inlet pipe (105) air in the cell as well as an outlet duct (120; 320) of air out of said cell, this device comprising a body (2; 202) and at least one active filtration element (3; 203), carried by the body,

characterized in that this device further comprises

at least one sleeve, known as the main sleeve (4; 204)

so-called main fixing means (25, 26, 27, 28), capable of fixing a first end (42; 242) of the sleeve on the body, in a sealed manner

the second end (43; 243) of the sleeve being open, so as to define a periphery (44; 244) of securing, capable of being secured in a sealed manner to a so-called main connecting member (6; 206), belonging to said installation, this main connection member being intended to cooperate with one of the inlet pipe and the outlet pipe.

It will be noted, first of all, that it is to the Applicant's merit to have understood the origin of the drawbacks, linked to the use of the known filtration devices described above. In substance, the Applicant has in particular identified that, in the known technique, a fraction of contaminated air bypasses the replacement filter, when the latter is put in place. Indeed, during this replacement phase, the walls facing this filter and the bag are not in mutual contact, so that they define intervals allowing the passage of stale air. The latter therefore has a tendency to infiltrate, in the direction of the downstream pipe within which, in theory, only decontaminated air should be present.

On the contrary, the invention provides for the use of a sleeve, fixed in a sealed manner to the walls of the filter. Under these conditions, the invention makes it possible to dispense with the untimely presence of the air passage intervals, which were mentioned above. Therefore, contaminated air does not bypass the replacement filter, when removing the used filter and then inserting the replacement filter. The invention therefore allows a truly secure method, as opposed to that proposed in the prior art. According to other characteristics of the invention: the fixing means are permanent fixing means (25), in particular by vulcanization or gluing.

the fixing means are removable fixing means, in particular by quick locking (26) or by wedging (27,28).

in the unconstrained state, the radial dimension of the sleeve is smaller than that of the body, and in which the sleeve has radial elasticity, allowing it to be fixed to the body.

the filtration device further comprises a so-called auxiliary sleeve (208), able to be secured in a sealed manner on a so-called auxiliary connecting member (209), intended to be placed opposite the main connecting member the device filtration comprises two active filtration elements (3a, 3b), arranged one behind the other in the direction of gas flow.

These additional features can be implemented with the first main object above, individually or in any technically compatible combinations.

The subject of the invention is also a controlled atmosphere installation (101; 301) comprising a working cell (1 10), an inlet pipe (105) for air in said cell, an outlet pipe (120; 320). ) air out of said cell, at least one filtration device (1; 201) as above, at least one main connecting member (6; 206), each of which is able to connect the fluid to the one of the inlet pipe and the outlet pipe with a respective filtration device, as well as securing means (65,66, 68,69; 265,266,268,269) capable of securing the mounting periphery of the main sleeve of each locking device filtration with respect to the main connection member.

According to other characteristics of the invention:

this installation further comprises sealing means between the opposite faces of the body of the filtration device (2; 202) and of the main connecting member (6; 206).

the filtration device is integrated in a box (130), and there is provided pressing means (137) of the main connecting member against the walls of the box.

the pressing means comprise a pressing member (137), the installation further comprising sealing means between the opposite faces of the pressing member and of the body of the filtration device. this installation further comprises an auxiliary connection member (209), able to connect by the fluid one of the inlet pipe and the outlet pipe with the filtration device, opposite the connection member main (206), as well as securing means (295,298) which are capable of securing the mounting periphery of the auxiliary sleeve of each filtration device relative to the auxiliary connecting member.

the auxiliary connection member has an opening (290) for the lateral passage of the filtration device.

an intermediate insert (360) is provided, intended to be removably fixed between the auxiliary connecting member and the section facing the inlet pipe or the outlet pipe.

the securing means comprise at least one groove (65,66; 265,266,295) formed in at least one connecting member, as well as at least one elastic element (68,69; 268,269, 298) capable of clamping the periphery of the respective sleeve in said groove.

the securing means further comprise at least one rigid element, each of which is attached to the outer periphery of a respective elastic element, the main connecting member (406) comprises means for expelling a fraction of air, outside the interior volume of the main sleeve (404), possibly outside the interior volume of the auxiliary sleeve.

these expulsion means comprise at least one non-return valve (472) putting into communication by the fluid, in one direction, a front face (461) of the connecting member (406) with the internal lateral face (462) of this connecting member.

the main connecting member (406) comprises so-called parting line testing means, which are able to cooperate with external parting line testing equipment.

the joint plane test means comprise a groove (480) formed in the downstream end face (461) of the connecting member, as well as a pipe (482) putting this groove in communication with the outer lateral face (463) ) of the collar.

the main connection member (406) comprises means (490) called pressure drop measuring means, which are able to cooperate with external equipment for measuring the pressure drop. this installation further comprises so-called sealed fixing means, which are capable of sealingly fixing the auxiliary connecting member (509) with the outlet pipe, respectively the inlet pipe.

the sealed fixing means comprise a bellows (525) extending between the opposite ends of the auxiliary connecting member (509) and of the outlet pipe, respectively of the inlet pipe, as well as a maneuver (526) capable of unfolding and folding said bellows.

These additional features can be implemented with the second main object above, individually or in any technically compatible combinations.

The subject of the invention is also a method for implementing a containment installation above, in which a first filtration device (1; 201), called used device, is replaced by a second filtration device (1 '), referred to as the replacement device, the used device and the filtration device being as above, process in which:

the used device is optionally surrounded with a container, made in particular of a heat-sealable material,

the sleeve of the used device, or the container, is divided into two sections, a first section (51) forming a sealed envelope (52) with the main connecting member (6), while the second section (55) forms a waterproof bag (56) with the body of the used device,

the second section, the body and the active element of the used device are removed, the second filtration device is supplied,

the sleeve (4 ’) of the replacement device (1’) is secured to the main connecting member, by surrounding said sealed envelope (52),

the first section of the used device, or of the container, is separated from the main connecting member,

forming a sealed pocket (59) containing the first section of the used device, separating said sealed pocket vis-à-vis the sleeve of the replacement device, then evacuating said sealed pocket.

DESCRIPTION OF FIGURES

The invention will be described below, with reference to the accompanying drawings, given solely by way of non-limiting examples, in which: [Fig. 1] is a schematic view illustrating a containment installation according to the invention.

[Fig. 2] is a longitudinal sectional view, illustrating a filtration device according to the invention, as well as a connection collar which both belong to the containment installation of the previous figure.

[Fig. 3] is a perspective view, schematically illustrating a sleeve belonging to the filtration device of the previous figure.

[Fig. 4] is a view in longitudinal section, illustrating on a larger scale a first embodiment of the attachment of the sleeve of FIG. 3, on the body of the filtration device. [Fig. 5] is a longitudinal sectional view, similar to FIG. 4, illustrating a second embodiment of the attachment of the sleeve of FIG. 3, to the body of the filtration device.

[Fig. 6] is a longitudinal sectional view, similar to Figures 4 and 5, illustrating a third embodiment of the attachment of the sleeve of Figure 3, on the body of the filtration device.

[Fig. 7] is a view in longitudinal section, illustrating the attachment of the filtration device of Figures 2 and 3 on the connecting collar.

[Fig. 8] is a longitudinal sectional view, illustrating the integration of the filtration device and its connection collar, inside a box.

[Fig. 9] is a view in longitudinal section, similar to FIG. 8 but on a reduced scale, illustrating a first step in the replacement of the filtration device.

[Fig. 10] is a longitudinal sectional view, similar to FIG. 9, illustrating a following step in the replacement of the filtration device.

[Fig. 11] is a view in longitudinal section, similar to FIG. 9, illustrating a following step in the replacement of the filtration device.

[Fig. 12] is a longitudinal sectional view, similar to FIG. 9, illustrating a next step in the replacement of the filtration device.

[Fig. 13] is a view in longitudinal section, similar to FIG. 9, illustrating a following step in the replacement of the filtration device.

[Fig. 14] is a view in longitudinal section, similar to FIG. 9, illustrating a following step in the replacement of the filtration device.

[Fig. 15] is a view in longitudinal section, similar to FIG. 9, illustrating a following step in the replacement of the filtration device.

[Fig. 16] is a view in longitudinal section, similar to FIG. 9, illustrating a following step in the replacement of the filtration device. [Fig. 17] is a longitudinal sectional view, similar to Figures 9 to 16, illustrating the last step in the replacement of the filtration device.

[Fig. 18] is a longitudinal sectional view, illustrating a filtration device according to a second embodiment, as well as connection collars which are intended to cooperate with this device.

[Fig. 19] is a top view, illustrating the filtration device and the connection collars of FIG. 18.

[Fig. 20] is a view in longitudinal section, similar to FIG. 19, illustrating a filtration device according to a first variant embodiment of this second embodiment. [Fig. 21] is a view in longitudinal section, similar to FIG. 19, illustrating a filtration device according to a further variant embodiment of this second embodiment.

[Fig. 22] is a view in longitudinal section, similar to FIG. 21, illustrating a first step in the replacement of the filtration device shown in this FIG. 21.

[Fig. 23] is a longitudinal sectional view, illustrating a second step in the replacement of the filtration device of Figures 21 and 22.

[Fig. 24] is a longitudinal sectional view, similar to Figure 2, illustrating another embodiment of the filtration device according to the invention.

[Fig. 25] is a longitudinal sectional view, similar to Figures 9 to 17, illustrating one of the steps for replacing a filtration device according to the prior art.

[Fig. 26] is a longitudinal sectional view, similar to Figures 9 to 17, illustrating a filtration device integrated into a box, after the operation of replacing a used filter previously removed from this box.

[Fig. 27] is a perspective view, partially illustrating a connecting member according to an advantageous embodiment of the invention, which is equipped with means for expelling the air present in the internal volume of the sleeve.

[Fig. 28] is a perspective view, on a larger scale, more particularly illustrating the detail 28 of FIG. 27, in particular the production of a hexagonal hole allowing the accommodation of a non-return valve.

[Fig. 29] is a longitudinal sectional view, similar for example to FIG. 7, illustrating the installation of the non-return valve in the hexagonal hole of detail 28.

[Fig. 30] is a longitudinal sectional view of detail 30 in FIG. 29.

[Fig. 31] is a perspective view, on a larger scale, illustrating from another angle detail 28 of FIG. 27, in particular the presence of means for measuring the pressure drop. [Fig. 32] is a perspective view, illustrating from another angle the means for measuring the pressure drop in FIG. 31.

[Fig. 33] is a perspective view, similar to FIG. 27, partially illustrating a connecting member which is equipped with so-called joint plane test means.

[Fig. 34] is a perspective view on a larger scale, illustrating detail 34 of figure 33.

[Fig. 35] is a longitudinal sectional view, similar for example to Figure 20, illustrating an advantageous variant of the invention involving tightening by bellows.

[Fig. 36] is a longitudinal sectional view, similar to FIG. 35, illustrating another functional position that the mechanical elements forming part of the variant of FIG. 35 are likely to adopt.

[Fig. 37] is a longitudinal sectional view, similar to Figure 35, illustrating yet another functional position which the mechanical elements forming part of the variant of Figure 35 are likely to adopt.

[Fig. 38] is a longitudinal sectional view, similar to Figure 35, illustrating a first step in the replacement of a filter, belonging to the variant of Figure 35.

[Fig. 39] is a longitudinal sectional view, similar to FIG. 35, illustrating a second step in the replacement of this filter.

[Fig. 40] is a longitudinal sectional view, similar to FIG. 35, illustrating a third step in the replacement of this filter.

[Fig. 41] is a view in longitudinal section, similar for example to FIG. 35, illustrating another advantageous architecture of the invention.

detailed description

Figure 1 schematically illustrates a controlled atmosphere installation according to the invention, which is a containment installation in the example described and shown. This installation, designated as a whole by the reference 101, first of all comprises a working cell, which is a containment cell 110 in the example described and shown. This cell 110, which is of a type known per se, will therefore not be described in more detail in what follows.

This cell comprises an inlet 11 1 as well as an outlet 112, shown schematically, from which respectively extend a so-called inlet pipe 105 and a so-called outlet pipe 120. The latter allows the flow, out of the cell 1 10, of contaminated air. This outlet pipe 120 has an upstream section 121 which opens into a filtration device according to the invention, designated in its together by reference 1 and which will be described in more detail in what follows. This filtration device purifies the stale air leaving the confinement cell 110.

In this first embodiment, the filtration device 1 is received in a box 130, which will also be described more precisely below. Downstream of the filtration device, the downstream section 140, known as the evacuation, of the outlet pipe 120 makes it possible to evacuate the air, purified beforehand in the filtration device 1, out of the confinement installation 101. Finally, a fan 150, also of a type known per se, allows the circulation of air in the containment installation. In the embodiment of Figure 1, this fan 150 is provided downstream of the installation, that is to say downstream of the cell 110.

With particular reference to FIG. 2, the filtration device firstly comprises a generally parallelepipedal body 2, forming a frame. The latter is hollowed out with a through opening 20, allowing the reception of an active filtration element 3. The latter, which will be referred to as a "filter" in the remainder of the present description, is of any suitable known type. Advantageously, this filter is in particular an THE (Very High Efficiency) type particle filter as defined in standard EN 1822. As a variant, other types of filters can be used, for example with activated carbon. We note respectively 21 and 22 the inner and outer peripheral walls of the body, 23 its upstream front face, namely oriented towards the outlet pipe, and 24 its downstream front face oriented towards the discharge section.

The filtration device 2 further comprises a sleeve, designated as a whole by the reference 4. The latter is shown schematically in FIG. 3, when it does not cooperate with the body 2. This sleeve defines an internal volume 41 bordered by a peripheral wall, which opens out at opposite ends, respectively 42 and 43. By way of nonlimiting examples, in the absence of external mechanical stress, the length of this sleeve is between 40 and 80 cm depending on the size of the filter . In particular, this sleeve should have a sufficient length for a correct performance of the cutting and welding operation, which will be described below in particular with reference to Figures 10 to 12.

Furthermore, the transverse dimension of this sleeve is substantially equal, or even slightly less than that of the body 2. This sleeve is made of any suitable material, ensuring a seal against gases, in particular air. One can use, according to a first variant, a sleeve made of a material not exhibiting radial elasticity. sensitive. This variant is very particularly suitable for sensitive or aggressive environments, in which this sleeve would be subjected to thermal, chemical, radioactive or mechanical stresses, or else should not itself be a contaminant for the confined enclosure or the environment. With this in mind, the sleeve can then be made, without limitation, of silicone, NEOPRENE ® or else of an airtight polymer of the polyethylene, polyurethane or even TEFLON ® type. Furthermore, in the case of very special applications, a combination of special textiles, of the fiberglass, KEVLAR ®, polyamide, or graphite type, with or without additional chemical coatings, can be used.

In use, the first end 42 of the sleeve 4 is fixed to the outer peripheral wall 22 of the body. As shown in FIGS. 4 to 6, different embodiments can be provided for this fixing. Thus, FIG. 4 represents a fixing of the permanent type, by gluing, vulcanization or the like. In this FIG. 4, the reference numeral 25 designates the corresponding fixing zone. On the other hand, FIGS. 5 and 6 show attachment methods of the removable type. In Figure 5, there is provided a locking element 26, making it possible to secure the sleeve. Furthermore, in Figure 6, the body is hollowed out by a peripheral groove 27, into which the free end 42 can be inserted, the latter being held in place by an elastic member 28 of toric shape.

According to the invention, this free end 42 is fixed to the body in a sealed manner. This means that gas, in particular contaminated air, present in the internal volume of the sleeve, cannot escape out of the latter through this end 42. In other words, the fixing means presented above make it possible to prevent any untimely leakage of this contaminated air, downstream of the sleeve.

The other free end 43 of the sleeve 4 is intended to cooperate with a collar 6, with a view to their mutual assembly. It will be noted that this collar 6 does not belong to the filtration device, according to the invention. In this regard, when implementing the installation according to the invention, the same collar 6 can cooperate with successive filtration devices. For this purpose, the free end 43 of each sleeve is open, so as to delimit a periphery 44 called securing on this single collar.

As shown more particularly in Figure 2, the inner peripheral wall 61 of this collar 6 defines a shoulder 62, intended to come into abutment against the front face 23 of the body 2. During this abutment, this shoulder and this front face provide a seal aimed at preventing any untimely leakage of air. For this purpose one can use a seal, not shown, of any suitable type, which is interposed between this shoulder and this front face. Furthermore, the outer peripheral wall 64 is hollowed out by two grooves 65 and 66, placed one behind the other with reference to the main axis X1 of the device. In its downstream part, illustrated at its lower end in this figure, this collar 6 defines a cap 67 surrounding the end facing the body 2.

FIG. 8 illustrates in more detail the box 130, to which it is briefly mentioned above. This box, of conventional type, has two axial openings 131 and 132 respectively, into which respectively open the two sections of the outlet pipe. When replacing the filtration device, each of these openings can be closed by a respective isolation damper 133 and 134. Furthermore, this box is equipped with at least one access door, in this case two. doors 135 in this embodiment, which are placed laterally with reference to the air flow.

The downstream end face 24 of the body rests in normal service against a clamping device 137, in a manner known per se. By way of non-limiting examples, this clamping device uses a jack, a pneumatic return spring, a lever or the like. In a manner known per se, the face 24 of the body and the clamping device 137 provide a seal against the flow of air. For this purpose it is possible to use a seal, not shown, made of any suitable material, typically continuous neoprene. On the side of the main upstream opening 131, a sheath 138 is fixed to the collar by any appropriate means, for example by bolting, welding, Jacobs type fittings or the like. The clamping device conventionally allows this sheath to be pushed against the wall of the box bordering the opening 131, so as to seal the flow of air.

The implementation of the confinement installation 101 above, in particular the operation aimed at replacing the filtration device 1, will now be described in what follows. In normal service, the filtration device is mounted on the collar 6. For this purpose, the periphery 44 of the sleeve is inserted into the grooves of the collar, then is held in position by respective holding members 68 and 69. In a similar manner to what has been explained above for the free end 42, the periphery 44 is secured to the collar 6 in a sealed manner. This means that the contaminated air, present in the interior volume of the sleeve, cannot escape at this periphery. Advantageously, provision can be made to secure the support, provided by the elastic elements 68 and 69. In this spirit, it is for example possible to envisage using an additional mechanical element, of the non-elastic type. The latter will typically be attached to the outer periphery of a respective elastic element, so as to ensure that each seal remains reliably in its receiving groove, in particular in the case of an overpressure inside the sleeve which would generate risk of pulling out. In constructive terms such an inelastic element can, by way of non-limiting examples only, be a ratchet strap.

It is now assumed that filter 3 is clogged, ie that it can no longer perform its initial function correctly. The level of fouling can be measured in real time, by any appropriate means not shown. As an alternative, it can be considered that the filter should be changed after a predetermined service life, which eliminates the need for real-time measurement. In either of these cases, the operator is warned that it is necessary to replace the filtration device 1, which will be referred to in the following as the used device.

With a view to this replacement, the air circulation inside the outlet pipe 120 is first of all stopped. In addition, the openings 131 and 132 of the box 130 are closed by means of the isolation registers 133. and 134. Then, as shown in Figure 9, the clamping device 137 is retracted and the sleeve 4 is extracted through the door 135 from the interior volume of the box (see arrow F1). The sleeve 4 is then tightened in its middle part, so as to form a constriction 50 (see FIG. 10).

The material constituting the sleeve is then cut, as shown in Figure 1 1, so as to divide the latter into two sections 51 and 55, on either side of the location of the constriction 50. As a variant not shown, it is possible to overcome the above constriction by using, for example, a heat-sealing bar. The latter, of a type known per se, sandwiches the material and then the soda.

It will be noted that this cutting operation is carried out in a sealed manner, namely that the contaminated air initially present in the sleeve remains confined in one or other of the sections 51 and 55. For this purpose, the man those skilled in the art will use all appropriate means, in particular cutting by means of a welding device, such as a heat sealer. More precisely, the section 51 forms an envelope 52 delimited by the periphery 44 of the sleeve, as well as the zone 53. At the level of the latter, a cut is made after the solder mentioned above. This cutout can be made on a weld line or else, in certain cases, the thermo-welding device makes this cut by the very fact of welding. Furthermore, the section 55 forms a bag 56 delimited by the free end 42 of the sleeve, as well as the zone 57 for cutting and then welding.

Then, as shown in Figure 12, the elastic 69 is withdrawn from the upper groove, according to the arrow f69, so that an end ring 56 belonging to the casing 52 falls back by gravity. At the same time, there is an additional rubber band, denoted 69 ’, immediately above the 69 which has just been removed. Furthermore, the used filtration device, formed by the body, the filter and the bag 56, is evacuated with a view to subsequent treatment of the filter 3. This treatment, which is not part of the invention, may consist of regeneration. or in incineration.

An additional filtration device 1 ’, hereinafter referred to as the replacement device, is then supplied. The latter has a structure identical to that of the used device 1, which has been described in detail above. In what follows, as well as in the figures, the mechanical elements of this replacement device, which are similar to those of the used device, are assigned the same reference numbers to which the suffix “prime” is added.

As shown in Figure 13, we place the periphery 44 'of the replacement device in the upper groove 66. It will be noted that, at the end of this operation, the walls of the sleeve 4' surround the pocket 52. In other words, the latter is confined within this sleeve. Then the additional rubber band 69 ’, mentioned above, is introduced into the upper groove 66, according to the arrow f69’ (see figure 14). This makes it possible to secure the sleeve 4 ’, relative to the collar 6. The section 51 is then detached from the used sleeve 4, relative to this same collar 6 (see Figure 15). To this end, the operator pulls on the free ring 56, so as to extract both the section 51 and the elastic 68, out of the groove 65.

The assembly formed by this section and this elastic is then moved, in the vicinity of the wall of the sleeve 4 ′, then this sleeve is handled, so as to form a closed pocket 59, containing the section 51 and the elastic 68. This pocket is then separated from the sleeve, by any suitable operation, in particular by heat welding (see figure 16). This bag can then be evacuated, with a view to subsequent treatment such as incineration. Finally, as shown in this same FIG. 16, the elastic 69 is inserted into the lower groove 65, according to the arrow f'69. This makes it possible to avoid any untimely tearing of the replacement sleeve, relative to the collar 6. The replacement device 1 'is then axially brought together, so that its front face 23' abuts against the shoulder 62 of the collar (see arrow f1 'in figure 16). This replacement device 1 'is then in a functional configuration, illustrated in FIG. 17. It is then possible to reopen the isolation registers 133 and 134, then to put the fan 150 back into service. consequently circulates again in the containment cell, then successively in the outlet pipe 120, the replacement device 1 'and in the evacuation section 140.

In some cases, the constraints to be met prevent a cutout and a tight weld of the sleeve, as described above. In this eventuality, the replacement of the used device comprises an additional phase, which is implemented before the steps described with reference to FIGS. 10 to 17. In essence, it is initially a question of surrounding, within a containing heat-sealable material, the assembly formed by the filtration device to be replaced and its sleeve.

To this end, the upper elastic 69 is first extracted from the groove 66, so as to release the end 43 of the sleeve, then this elastic is replaced in its groove in order to immobilize the end of the container with respect to the collar 6. The lower elastic 68 is then extracted from its groove 65, so that both this elastic and the entire sleeve are now detached from the collar 6. Then the steps described are implemented. with reference to Figures 10 and 11, by means of a step of cutting and welding the above container, similar to that implemented on the sleeve 4.

At the end of this step, the above container is divided into two sections, which are similar to those respectively 51 and 55 shown in FIG. 11. The section similar to that 55, which contains in particular the body and the active element of the used device, is then evacuated. Then the sleeve of a replacement device is placed on the collar 6, in a manner analogous to what has been described in Figures 13 to 16.

Figures 18 and 19 illustrate a containment installation 301, according to a second embodiment of the invention. In these figures, the mechanical elements similar to those of the preceding figures are assigned the same reference numbers, increased by the number 200. This confinement installation 301 differs from that 101 in particular in that it does not have a box, such as that 130. On the other hand, it is equipped with two connection collars, namely a connection collar called upstream or main 206, as well as a connection collar called downstream or auxiliary 209. These collars are arranged on either side of the filtration device 201, with reference to the direction of air flow. The installation 301 further comprises a containment cell, not shown, which is similar to that 110 of the first embodiment. Furthermore, in this second embodiment, the fan is typically provided downstream of the installation, namely at the outlet of the discharge section 340. In Figures 18 and 19, this fan is not shown either.

Furthermore, this filtration device 201 is provided with a first sleeve 204 called upstream or main, as well as a second sleeve 208 called downstream or auxiliary. Advantageously, these sleeves are made in one piece. In other words, they are formed from a single mechanical element 288 which is fixed, in an intermediate zone 289, on the body 202 of the device 201. This fixing may be similar to one of those, described in reference to Figures 4 to 6. However, as a less preferred variant, it is possible to provide for the use of separate sleeves, each of which is attached separately to this body.

The main sleeve 204 is intended to cooperate with the collar 206, in a manner analogous to the cooperation between the sleeve 4 and the collar 6. Furthermore, the sleeve 208 cooperates with the collar 209. To this end, these mechanical elements are generally similar. respectively to the sleeve 204 and to the collar 206. The auxiliary collar 209 however differs from the main collar 206, in particular in that it is provided with a single groove 295. This is in particular due to the fact that, downstream of the auxiliary collar, the contaminated air is no longer present. In other words, since only clean air is present in this area, tightness is not a critical aspect. The aforementioned groove 295 is able to cooperate with an elastic 298, with a view to fixing the periphery 284 of the auxiliary sleeve 208. This auxiliary collar 209 allows connection to the discharge section 340, by any suitable means, in particular by screwing.

Furthermore, the auxiliary sleeve differs from the main sleeve, in particular in that it typically has a shorter length. However, in the case of several filtration barriers in series, as shown in Figure 24, the sleeve intermediate then plays the role of upstream section for a first filter, and downstream section for the other filter. It is then preferred that the sleeve is long enough to allow the cutting and welding described above.

According to the first variant of Figures 18 and 19, an opening 290 is provided in the auxiliary collar 209 to allow passage of the filtration device. In this case, an axial rail 292 is provided, forming a guide, which allows the filtration device to be held in place. It will be emphasized that, at the level of the interface between the downstream end face of the body 202 and the rail 292, airtightness is not mandatory. It will also be noted that, in the top view of FIG. 19, the sleeves 204 and 208 are not shown.

According to a second variant, illustrated in particular in Figures 21 and 22, this auxiliary collar 209 is fixed indirectly on the discharge section 340, by means of an insert 360 in the form of a ring. This insert 360 is removably fixed, by any suitable means, both on the auxiliary collar 209 and on the pipe 340. The above steps, which are of a type known per se, are not described in more detail.

In the event that the filtration device 201 has to be replaced, it is first of all a matter of separating this device 201 from the upstream connection collar. In the first variant embodiment, this device is brought out through the aforementioned opening 290, according to arrow f201 in FIG. 18. In the second variant, the insert 360 is first of all removed laterally, according to arrow f360 on FIG. 22. It is then possible to move the downstream collar axially along arrow f309, then to move the filtration device away along arrow f'201 in this same figure 22.

Once this device is remote from the upstream collar, the same steps are implemented as those which have been described with reference to FIGS. 9 to 17. In the present description, only FIG. 23 has been shown the step according to FIG. which forms a constriction 250 in an intermediate zone of the main sleeve 204.

An advantageous variant, relating to the second embodiment of the invention, is illustrated in FIG. 20. In this variant, a system can be provided which ensures tightening between the filtration device and the downstream connection collar. To this end, the downstream collar 209 is equipped with a rod 225, which is slidably received in an orifice 299 formed in the downstream collar 209. In use, this rod 225 is capable of exerting pressure on the face facing the body 202, according to arrow F225. It will be emphasized that, at the level of the faces opposite the body and the stem, air tightness is not compulsory. This rod 225 can be mobilized by any suitable means, of a type known per se. It is for example a jack, a spring, an auxiliary threaded rod, or else an eccentric mechanism. Conventionally, this clamping system makes it possible to confer a so-called seismic qualification on the installation according to the invention.

Another alternative embodiment is illustrated in Figure 24. In the previous figures, the filtration device has a single frame, as well as a single filter. In the variant of Figure 24, the body of the filtration device is formed by two frames 2a and 2b, arranged one behind the other in the direction of air flow. Each of these frames is equipped with a respective filter 3a and 3b. Furthermore, the sleeve 4 is fixed to each frame, according to one or the other of the possibilities illustrated in FIGS. 4 to 6. As a variant not shown, it is possible to provide that each of the frames is equipped with a respective sleeve, each sleeve being fixed on its support frame according to one or the other of these possibilities. It is possible to provide for the use of a greater number of filters, possibly going up to four, for example. It is possible to provide for the use of either filters of the same type or filters of different types. The fact of using filters of different types in series is advantageous; these filters may have different fineness, but also different applications, for example spark arrestor or activated carbon.

The invention has many advantages over the prior art. In this regard, Figure 25, which is similar to Figure 9 above, illustrates one of the phases of replacing a filtration device according to the prior art. In this figure 25, the mechanical elements similar to those of Figures 9 to 17 are assigned the same reference numbers, increased by the number 1000.

When replacing the used filtration device 1001, the prior art provides for inserting the latter into a pocket 1004. However, the latter is not fixed in a sealed manner to the walls of the body 1002. In this way there are intervals I, allowing the passage of contaminated air in the direction of the downstream part of the box 1 130. Under these conditions, once the replacement filtration device 1001 'is installed in this box, there is a fraction of contaminated air denoted FC on the side of the discharge section 1140. This contaminated air is then treated as being clean air, which is particularly dangerous in terms of safety. FIG. 27 illustrates a connecting member 406, or collar, which conforms to an advantageous variant of the invention. This connection member incorporates additional functionalities, compared to the various embodiments above, which will be described below.

We first note 460 and 461 the opposite end faces of this collar 406, downstream and upstream respectively, with reference to the flow of the fluid that is to be filtered. We further note 462 and 463 the opposite side faces, respectively internal and external. As shown in particular in FIG. 28, the downstream end face 461 is hollowed out by a housing 470, intended to receive at least one non-return valve 472, more particularly visible in FIGS. 29 and 30. A channel 473, overall L-shaped, connects the bottom 471 of the housing with the internal side face 462. In the example illustrated, the housing 470 is hexagonal, it being understood that it can have any other suitable shape, in particular circular. Furthermore, the example illustrated shows two non-return valves 472, it being understood that the invention also finds its application to a single valve of this type.

In service, when a new filtration device is put in place, a volume of air is trapped in the internal volume of the sleeve 404. However, the presence of this volume of air can prove to be untimely. Consequently, in accordance with the present advantageous variant of the invention, the non-return valve (s) 472 make it possible to perform an expulsion function of this volume of air.

In practice, an operator typically compresses the walls of this sleeve 404. Under these conditions, an opening of the or each valve 472 occurs, allowing air to flow according to the arrows F4 in FIG. 30. This flow makes it possible to expel the aforementioned volume of air out of the sleeve, in this case in the direction of the upstream side of the filter. In addition, any air flow in the opposite direction, according to the crossed out arrow F5 in this same figure 30, is prohibited thanks to the non-return valve (s). This is to prevent inadvertent swelling of the sleeve, which could lead to its accidental rupture.

Once this expulsion has been carried out, as described above, the usual use of the filtration device can be initiated. In essence, as shown in FIG. 29, the air to be filtered can flow upstream of the collar 406, according to the arrow F1. There is then a main flow of air through the filter, according to arrow F2. As shown now with reference to FIGS. 31 and 32, the collar 406 advantageously comprises means for measuring the pressure drop. For this purpose, a channel 490 is provided, mutually connecting the opposite side faces 462 463 of the collar 406. In service, the operator uses an auxiliary equipment, capable of being connected to the channel 490. This auxiliary equipment, which is of the type known per se, is not described in the figures. According to a first possibility, a connector can be placed in this channel, which makes it possible to connect a HEPA type filter, itself associated with a pressure sensor. Alternatively, a sealed quick connector can be placed in this channel, which allows air to pass only when a male connector is inserted. Finally, one can imagine a solution involving a combination of the two possibilities above.

As shown now in Figures 33 to 34, the collar 406 advantageously comprises means, allowing the adaptation of a so-called joint plane test equipment. For this purpose, the downstream front face 460 is hollowed out with a peripheral groove 480, extending near the central opening of this collar. Furthermore, a pipe 482 places this groove 480 in communication with an orifice 485, opening onto the outer lateral face 463 of the collar.

In service, parting line test equipment is used, of a type known per se, which is not described in the accompanying figures. This equipment typically makes it possible to carry out the procedure, described for example in the German standard DI N 25 496. For this purpose, it is for example possible to use equipment of the “leak test device” type, which consists of a hand pump associated with a pressure gauge. The latter makes it possible to increase the pressure of the groove, for example to 2000 Pa, then to identify whether this pressure eventually drops. If not, it means that the test is satisfactory. On the other hand, if this pressure drops significantly, it means that there is a defect in the parting line. This procedure is only performed after the filter is in place and tightened.

Figures 35 to 40 now illustrate a particularly advantageous variant of the invention, which is to be compared to the variant of Figure 20. In these Figures 35 to 40, the mechanical elements similar to those of Figure 20 are assigned the same numbers. of reference, increased by the number 300.

As mentioned above, the downstream sealing is not a crucial aspect in the variant of Figure 20. On the other hand, the variant of Figures 35 to 40 takes this tightness requirement is taken into account, also downstream of the filter. This sealing requirement, both upstream and downstream, may find its use in certain industrial applications.

To this end, we will mention in particular the installations for which several filtration levels must be linked together, before the air is discharged. For example, in a P4 type laboratory, it is necessary to have two HEPA type filters on the extraction, before air discharge. In this case, the variant according to the invention can be placed at the level of the first filter. We will also mention the installations for which the operators must not be exposed to the air, even downstream of the filter. In this case, it is for example the nuclear field for which, although the air is considered as “clean” downstream of the filter, the possible dilution effect on discharge is necessary in order to be considered as “safe”.

Structurally, in this variant of Figures 35 to 40, the auxiliary sleeve 508 is fixed on the auxiliary collar 509, in the same way that the main sleeve 504 is fixed on the main collar 506. In essence, this auxiliary collar is provided with two grooves 595 and 596, which are analogous to the grooves 565 and 566 provided on the main collar. Furthermore, two elastic bands 598 and 599 are provided, which cooperate with these respective grooves.

Moreover, in this variant of Figures 35 to 40, the auxiliary collar 509 is fixed to the discharge section 640 in a sealed manner. For this purpose, a bellows 525 is provided connecting the downstream end of this collar with the periphery 641 of this discharge section. Furthermore, an operating member, in the example illustrated a threaded rod 526, allows this bellows to be unfolded, so as to allow this collar 509 to move relative to this discharge section 640. Regarding this last aspect, the various relative positions of the collar and of the discharge section are illustrated in Figures 35 to 37. Note that, in Figure 35, the bellows is in its unfolded configuration while, in Figures 36 and 37, it adopts its configuration folded. Whatever its configuration, the air cannot escape to the outside due to the presence of the sleeve 508 and of the bellows 525. As a variant, other equivalent mechanisms of the threaded rod 526 can be used, in particular a mechanism of the “push clamp” type.

Figures 38 to 40 now illustrate different steps, making it possible to replace the used assembly, formed by the filter 503, as well as the sleeves 504 and 508. To this end, we moves the filter laterally, according to arrow F 503 in FIG. 38. This movement can be carried out without loss of sealing, thanks to the presence of the sleeves as well as of the bellows. Then cuts 505 and 507 are made, shown in dotted lines in FIG. 39. This makes it possible to remove the used assembly mentioned above, along the arrow F500 in FIG. 39. It will be noted that, at the end of this cutting, closed ends 504 ′ and 508 ′ visible in FIG. 40 are formed, which constitute sealing plugs.

Finally, as shown in this same figure 40, a new assembly is supplied, formed by a filter 603, as well as sleeves 604 and 608. This new assembly is then positioned in the vicinity of the aforementioned plugs, then is connected according to the arrow F600 in this figure 40. This connection is made in the same way as that which has been described above, while preserving the airtightness. It should be noted in particular that, in this variant of FIGS. 35 to 40, the only passage of air between the upstream and downstream side of the filter necessarily takes place through this filter. The variant of Figures 35 to 40 may incorporate all or part of the functionalities provided at the level of the connecting member, which are described with reference to Figures 27 to 34.

Figure 41 illustrates another possible implementation of the invention. In this figure, there are two filters placed in series. Furthermore, a collar according to the invention is arranged in the middle position, which can be equipped with all or part of the functions described above.

The invention is not limited to the examples described and shown above. Thus, a controlled atmosphere installation has been illustrated, which is a containment installation equipped with a filtration device provided downstream of the containment cell. As a variant, provision can be made for this controlled atmosphere installation to be equipped with an additional filtration device, provided upstream of this containment cell. According to yet another variant, the work cell is not a containment cell, but a high purity cell, for example of the clean room type. In this case, the installation incorporating this work cell is typically equipped with a filtration device, placed upstream of this high purity cell.

Claims

1. Filtration device (1; 201) for a controlled atmosphere installation (101; 301), said installation comprising a working cell (110), an inlet pipe (105) for air in the cell and a outlet duct (120; 320) of air out of said cell, this device comprising a body (2; 202) and at least one active filtration element (3; 203), carried by the body,

characterized in that this device further comprises

at least one sleeve, called main (4; 204)

2. Device according to the preceding claim, wherein the fixing means are permanent fixing means (25), in particular by vulcanization or gluing.

3. Device according to claim 1, wherein the fixing means are removable fixing means, in particular by quick locking (26) or by wedging (27, 28).

4. Device according to one of the preceding claims, wherein the filtration device further comprises a said auxiliary sleeve (208), adapted to be secured in a sealed manner on a said auxiliary connecting member (209), intended to be placed. opposite to the main connecting member.

5. Device according to one of the preceding claims, wherein, in the unconstrained state, the radial dimension of the sleeve is less than that of the body, and wherein the sleeve has radial elasticity, allowing its attachment to the body.

6. Device according to one of the preceding claims, wherein the filtration device comprises two active filtration elements (3a, 3b), arranged one behind the other in the direction of gas flow.

7. Controlled atmosphere installation (101; 301) comprising a working cell (1 10), an inlet pipe (105) of air in said cell, an outlet pipe (120; 320) of air out of said cell, at least one filtration device (1; 201) according to any one of the preceding claims, at least one main connecting member (6; 206), each of which is suitable for fluidly connecting one of the inlet pipe and outlet pipe with a respective filtration device, as well as securing means (65, 66, 68, 69; 265, 266, 268, 269) capable of securing the mounting periphery of the main sleeve of each filtration device relative to the main connection member.

8. Installation according to the preceding claim, further comprising sealing means between the facing faces of the body of the filtration device (2; 202) and of the main connecting member (6; 206).

9. Installation according to claim 7 or 8, wherein the filtration device is integrated in a box (130) and in which there is provided pressing means (137) of the main connecting member, against the walls of the box. .

10. Installation according to the preceding claim, wherein the pressing means comprise a pressing member (137), the installation further comprising sealing means between the facing faces of the pressing member and the body of the device. filtration.

1 1. Installation according to one of claims 7 to 10, wherein the main connecting member (406) comprises means for expelling a fraction of air, out of the interior volume of the main sleeve (404), possibly outside the internal volume of the auxiliary sleeve.

12. Installation according to the preceding claim, wherein these expulsion means comprise at least one non-return valve (472) placing in communication by the fluid, in one direction, a front face (461) of the connecting member ( 406) with the internal lateral face (462) of this connecting member.

13. Installation according to one of claims 7 to 12, wherein the main connecting member (406) comprises so-called joint plane test means, which are able to cooperate with an external joint plane test equipment. .

14. Installation according to the preceding claim, in which the means for testing the parting line comprise a groove (480) formed in the downstream end face (461) of the connecting member, as well as a pipe (482) putting in communicating this groove with the outer lateral face (463) of the collar.

15. Installation according to one of claims 7 to 14, wherein the main connection member (406) comprises means (490) called measuring the pressure drop, which are able to cooperate with external measurement equipment. of the pressure drop.

16. Installation according to one of claims 7 to 15, wherein this installation further comprises an auxiliary connecting member (209), capable of connecting by the fluid one of the inlet pipe and the outlet pipe with the filtration device, opposite the main connecting member (206), as well as securing means (295, 298) which are able to secure the mounting periphery of the auxiliary sleeve of each filtration device with respect to to the auxiliary connection device.

17. Installation according to the preceding claim, wherein the auxiliary connecting member has an opening (290) for lateral passage of the filtration device.

18. Installation according to claim 16 or 17, wherein there is provided an intermediate insert (360), intended to be removably fixed between the auxiliary connecting member and the section facing the inlet pipe or the outlet pipe.

19. Installation according to claim 16, wherein this installation further comprises so-called sealed fixing means, which are capable of sealingly fixing the auxiliary connecting member (509) with the outlet pipe, respectively the pipe. entrance.

20. Installation according to the preceding claim, wherein the sealed fixing means comprise a bellows (525) extending between the opposite ends of the auxiliary connecting member (509) and of the outlet pipe, respectively of the pipe. input, as well as an operating member (526) capable of unfolding and folding said bellows.

21. Installation according to one of claims 7 to 20, wherein the securing means comprise at least one groove (65, 66; 265, 266, 295) formed in at least one connecting member, as well as at least one elastic element (68,69; 268,269, 298) adapted to wedge the periphery of the respective sleeve in said groove.

22. Installation according to the preceding claim, wherein the securing means further comprise at least one rigid element, each of which is attached to the outer periphery of a respective elastic element.

23. A method of implementing an installation according to one of claims 7 to 22, wherein a first filtration device (1; 201), called used device, is replaced by a second filtration device (1 ') , referred to as a replacement device, the used device and the filtration device being in accordance with one of claims 1 to 6, process in which:

the sleeve of the used device, or the container, is divided into two sections, a first section (51) forming a sealed envelope (52) with the main connecting member (6), while the second section (55) forms a waterproof bag (56) with the body of the used device

the second section, the body and the active element of the used device are removed

we supply the second filtration device

the sleeve (4 ’) of the replacement device (1’) is secured to the main connecting member, surrounding said sealed envelope (52)

the first section of the used device, or of the container, is separated from the main connecting member