DEVICE FOR FEEDING A CONTAINER FOR AN INSTALLATION FOR THE HEAT TREATMENT OF WASTE

Abstract

A sleeve made of rigid tube into which the feed lines for feeding the waste to treated and the gases to be discharged lead. In order to avoid contamination or blockage of the sleeve, a tool for scraping the inner face of the wall thereof is added, in this case a terminal tubular section of one of the feed lines, which carries out orbital movements tangent to this inner face. Various cooling, rinsing and overpressure structures are added, as is a docking device extending at the bottom of the sleeve for connecting the latter to the heat treatment container.

Description

The present invention relates to a feeding device for an installation for the heat treatment of waste.

The heat treatment methods set forth herein are particularly intended to condition certain dangerous products, typically waste from the nuclear industry, in a suitable matrix before storing it. It is taken in containers associated with heating means that bring their content to high temperature. These heating methods may be the following: a two-step method for vitrifying with calcination of the waste then melting with a glass frit in a melter before pouring into a container in view of storage and subsequent disposal, or a method for vitrifying in a cold crucible, or also a method according to which the heat treatment of waste and of the material of the matrix are brought to temperature directly in the canister intended to be stored and disposed of. The containers considered here and thus named in the following description are globally equipment into which the waste or the material of the matrix will be fed, for example a can, a crucible, a calciner, a canister, etc.

Certain technical difficulties inherent to these methods pertain to feeding the waste into the installation wherein the heat treatment method is implemented. It is usual to have a vertical sleeve above the container, to dock it with a top opening of one of the containers by a downward movement of the sleeve to guarantee the containment of the installation, to avoid the dispersion of volatile gases and particles into the environment and to pour the waste and products feeding the heat treatment method through respective pipes that lead to the inside of the sleeve. The products feeding the heat treatment method are here defined as all of the ingredients mixed to implement the heat treatment methods, therefore both the dangerous products, that is to say the waste, and the material of the conditioning matrix, the latter being able to be formed of precursors of the matrix, in particular glass precursors. This material is often a glass frit, and the waste is of very diverse natures, but a significant portion is viscous, sticky, very finely fragmented, or powdery. All of these products are likely to foul the inner face of the wall of the sleeve instead of falling in the container. This risk of fouling is increased by releases of gases during the heat treatment, which rise in the sleeve before being discharged, and which comprise fumes highly loaded with impurities, particles that may deposit on the inner face of the wall of the sleeve. Such a fouling adversely affects the service life of the sleeve, which risks no longer operating, or no longer enabling a suitable flow towards the container or also becoming blocked; there is also a risk regarding the safety around the installation after disconnecting the container, especially if the products deposited in the sleeve disperse into the environment.

Other difficulties relate to the docking of the sleeve around the opening of the container, that is desired to be completely sealed in order to maintain sealing as regards the gases while keeping the content of the container inside the latter during the heat treatment, but which is in reality difficult to carry out well because it must be accomplished at a distance by remote-controlled actuators, and the significant thermal expansions produced during the heat treatment are always likely to distort the adjustment obtained when cold.

Therefore, a main object of the invention is to combat the fouling of the inner face of the wall of the sleeve and of other surfaces of the devices, while facilitating the docking of the sleeve on the container.

In a general form, the invention pertains to a device for feeding a container for an installation for the heat treatment and conditioning of waste, comprising a sleeve having a lower opening to be docked with an upper opening of the container, a first line for feeding the waste to be treated connecting to the sleeve and penetrating therein, the sleeve containing a tool for scraping its inner face, characterised in that the scraping tool is a sheath of axis parallel to the sleeve and forming a terminal section of the first feed line, and the device comprises a support of the sheath, the support being provided with a motorised off-centring mechanism to which the sheath is suspended, the off-centring mechanism moving the sheath in orbits where it is adjacent to the inner face of the sleeve.

The scraping tool reduces or prevents the fouling of the sleeve. It may be active during the heat treatment operations to scrape away the fouling products, before they solidify.

As it coincides with a feed line already present in the known devices (where the feed line is however immobile and separated from the wall of the sleeve), the tool does not complicate the device or hinder the flow of products feeding the heat treatment method when they exit the feed lines to be guided towards the container, or the discharging of gases. The document JP 2014-134350 A on the contrary relates to a device where the lines for feeding the constituents of a mixture to be treated in a converter are occupied by rotating swirlers the rotation of which prevents the constituents from adhering to the wall of the feed lines. These tools have the drawback of complicating the device and of occupying the entire section of the feed lines, therefore hindering the free flow of the constituents along the lines. The design is not suitable for a sleeve for docking with a container, which is occupied by one or more feed lines through which pass the respective constituents of a mixture to be treated. In addition, JP S61-11519 A will be cited, which describes an installation for transporting waste that may particularly be equipped with a rotating swirler and a paddle wheel to advance the waste, without the rotating swirler seeming to have a scraping effect.

A construction favourably making it possible to place the sheath and its transverse movement off centre, without adversely affecting the sealing of the device, is characterised in that the sheath extends beyond the sleeve in a direction opposite the lower opening, through a sealing plate at an upper end of the sleeve, the sealing plate comprising a movable plate connected to the sheath, and a fixed plate connected to the sleeve and in front of which the movable plate moves, the fixed plate being provided with an opening for passage of the sheath that is wider than the sheath, and a sealing device connects the fixed plate to the movable plate.

In a concrete embodiment, the off-centring mechanism comprises a toothed gear wheel to which the sheath is suspended, without being coaxial with an axis of rotation of said toothed wheel.

The scraping is significantly improved if (according to a particularly preferred embodiment) the off-centring mechanism is arranged to also make the sheath rotate about itself.

An appropriate construction then comprises a gear between a toothed wheel attached to the sheath and a toothed crown attached to the off-centring mechanism, and the sheath is rotatably mounted in the toothed gear wheel, to which it is suspended.

The scraping is facilitated if the sheath has an excrescence, in particular a helical blade, on its outer face and may thus push the fouling products back downwards as it detaches them, while rotating about itself.

The often viscous and sticky or even powdery nature of the waste to be treated may also impose precautions to avoid fouling or blockages elsewhere in the sleeve. This is the case in a particular embodiment, the invention is characterised in that the first feed line contains at least one rotating swirler (called “pigtail”) to advance or accompany the waste to be treated.

Thus, a portion of the first feed line consists of a vertical section containing a swirler, or helical conveyor, which must follow the possible orbital movements of the sheath, which may be obtained if, in connection with certain optional features already mentioned, the swirler extends beyond the sheath in the direction opposite the lower opening of the sleeve, is suspended to a second motorised off-centring mechanism, synchronised with the off-centring mechanism to which the sheath is suspended, and is rotated by a motor mounted on the second off-centring mechanism.

Synchronisation may be ensured if for example the off-centring mechanism to which the sheath is suspended and the second off-centring mechanism are mechanically connected to one another and driven by the same motor.

The feed lines are generally formed of a plurality of successive sections connected to one another. A construction of the first feed line, compatible with the movable layout of the end of the sheath in the sleeve, is characterised in that the first feed line comprises an upstream section, forming an angle with the terminal section and connected to the terminal section by an overflow unit, the terminal section being provided with a funnel at its top, which is connected to a pierced lower face of the overflow unit, the sheath being movable under the overflow unit.

This construction is also advantageous because it permits translational movements of the sheath in the sleeve following their axial direction, in order to lower the sheath to the end of the sleeve and even into the container after docking, and to thus reduce the fouling of the sleeve by the waste to be treated arriving through the first feed line.

If the sheath is sliding in the axial direction of the sleeve, the upstream section is advantageously tilting by being hinged, at its two ends, to a fixed point of the device and to a wall of the overflow unit.

Like the sheath, the upstream section may be equipped with a motorised rotating swirler; it may further be connected, at an end opposite the overflow unit, to a hopper for pouring the waste to be treated.

The device comprises, in many applications, a second feed line of the container, made of the material of a waste conditioning matrix, this second line opening into the sleeve. However, other applications include a single feed line, wherein the waste and the material of the conditioning matrix are transported, possibly after having been mixed; without this modifying the principle of the invention.

Another optional layout, the interest of which is to enable additional cleaning of the sleeve if the scraping by the tool of the invention is not sufficient, is characterised in that the sleeve consists of two portions in extension, that can be dismantled from one another and equipped with different coolant circuits, a lower portion of which comprising the lower opening, and an upper portion wherein the second feed line and a line for discharging vitrification gaseous products opens.

Other precautions for ensuring the correct sequence of the heat treatment operations apply to the need for the second feed line, which is then provided with a scraper of its inner face.

This scraper may however be quite different from the scraping tool set forth herein: a construction, advantageous due to its simplicity, consists of a ram sliding in a section of the second feed line adjacent to the sleeve, and housed in an extension of said section of the second feed line, beyond an upstream section of the second feed line forming an angle with said section adjacent to the sleeve.

Scraping may also be completed with rinsing. In this way a hole and a rinsing liquid pipe advantageously pass through the ram above.

In order to facilitate the docking manoeuvres, it is recommended for the sleeve to comprise a main rigid tubular portion and a docking device, the docking device comprising a docking sleeve surrounding the main portion by extending it downwards, comprising the lower opening of the sleeve, mounted on the main portion and movable along the main portion.

Docking is made easier, and less sensitive to thermal expansions, if the docking sleeve comprises a compressible portion in the direction of mobility of the docking sleeve.

A means for rinsing an annular volume between the docking sleeve and the main portion of the sleeve then makes it possible, if it exists, to reduce contamination, particularly related to contaminating volatile particles, and the fouling penetrating into this volume, especially due to the fumes of the heat treatment rising in the sleeve.

In one important embodiment, the compressible portion is a bellows and the rinsing means comprises inlet pipes in the annular volume that overhang the bellows, guided radially towards the main portion of the sleeve and producing bounces or splashes of rinsing liquid radially outwardly and towards the bellows.

It is also possible to add, also to combat contamination and fouling in this volume, a pipe for injecting overpressure gas into an annular volume between the docking sleeve and the main portion of the sleeve.

The guiding of the docking device is obtained if the docking sleeve comprises a docking sheath sliding on the main portion of the sleeve, and actuators for moving the docking sheath connecting the docking sheath to the main portion of the sleeve.

It is then possible to add a pipe for injecting flushing gas into an annular volume between the docking sheath and the main portion of the sleeve, also in order to prevent the intake of fumes loaded with contaminating particles.

Finally, checks of the sequence of the method are made possible by a pressure intake pipe comprising rinsing means, extending in a wall of the sleeve along the sleeve, and opening at a lower edge of the sleeve; or by a means for measuring the filling level of the container, disposed through the sleeve.

The invention will now be described in detail of its aspects, features and advantages by means of the following figures, which illustrate a particular embodiment, not exclusive of others, and which show:

FIG. 1: a general view of a particular installation for the heat treatment, namely “in can” vitrification, that is to say directly in the canister intended for storage and disposal, wherein the feeding device according to the invention may be used;

FIG. 2: a general view of the feeding device in a non-docking state of the container (“pigtail” raised);

FIG. 3: another general view of the same, in the docking state of the container (“pigtail” engaged in the container);

FIG. 4: the isolated sheath;

FIG. 5: the top of the sheath, in section;

FIG. 6: the device for supporting and driving the sheath, in general representation;

FIG. 7: a detailed view, in section and perspective, of a portion of this device;

FIG. 8: certain gears of this device;

FIG. 9: the top of the sleeve, in section and perspective;

FIG. 10: the support and drive device, and the neighbouring portions of the device, in section;

FIG. 11: the configuration of the device and of the container in the non-docking state;

FIG. 12: the configuration, in the docking state;

FIG. 13: a partial view of the sheath in section;

FIG. 14: the second feed line, in the normal state;

FIG. 15: this line, during scraping;

FIG. 16: details of the docking device;

FIG. 17: other details of the docking device;

FIG. 18: an inspection device.

FIG. 1 shows a vitrification installation. Radioactive waste vitrification containers are called cans 1, and they are successively provided in a furnace 2 here consisting of two semi-cylindrical halves that can be move closer to one another in order to clamp a can 1. The cans 1 have a neck 3, equipped with an upper opening 4 delimited by a flat flange 5, at their top. In reality, these are crucibles that withstand the very high temperatures produced during the vitrification operations. The furnace 2 may be with heating of the resistive type. Its upper lid 6 (shared between the two halves) includes a central opening 7 under which the neck 3 of the can 1 is located clamped by the furnace 2 during a vitrification operation. A station for pre-loading the cans 1, unrelated to the invention, bears the reference 8.

Interest will now be paid to a feeding device 9 adjacent to the furnace 2; FIG. 1 illustrates that it particularly includes: a sleeve 10, which mainly comprises a vertical cylindrical tube open downwards and that extends, in the disjoint state of the device preceding vitrification, facing the neck 3 of the can 1 clamped more or less at a distance above it; on the left side of this FIG. 1, appear means 12 for treating the gases from the vitrification operations, according to features known by the person skilled in the art and that do not form part of this invention.

The detail of the feeding device 9 becomes more apparent in FIG. 2. It comprises a line 11 for feeding waste to be treated, consisting of a vertical sheath 16 containing a swirler 18 that rotates therein, which is in the form of a helix with coils that are close together and not very inclined (“pigtail”), of a hopper 14 from which the waste is extracted and of an oblique section 15 connected to the vertical sheath 16. Optionally as shown in FIG. 2, the oblique section 15 contains a swirler 17 that rotates therein, also of the “pigtail” type.

Thanks to these means, the content of the first feed line 11 is forced to advance and to go down before dropping into the opening 4 of the can 1 located below the sleeve 10. The oblique section 15 and the sheath 16 connect to one another by an overflow unit 19. A drive device 20 extends above the sleeve 10. The rigid main tube of the sleeve 10 consists of a lower portion 21 and of an upper portion 22 that extends the preceding upwards, and that is connected thereto by an assembly of bolted flanges 23.

A second feed line 24, intended to feed the can 1 with a glass frit that constitutes the material of the conditioning matrix to obtain the final vitrified product, opens into the upper portion 22, in the same way as a gas removal line 25, at an altitude a little higher. The second feed line 24 particularly comprises a vertical section 26, a downward oblique section 27 that connects the vertical section 26 to the sleeve 10, and an extension 28 of the downward oblique section 27 that extends, in relation thereto, on the side opposite the sleeve 10. The invention may be applied to devices devoid of such a second feed line, if all of the products to be treated are introduced via the same feed line.

The lower portion 21 of the sleeve 10 comprises on its outer face a docking device 29 on the collar 5 of the can 1, and to which the lower opening 109 of the sleeve 10 belongs; the cylindrical tube consisting of the lower portion 21 and of the upper portion 22 stops a little above the lower opening 109.

These various main elements of the invention will be described in turn in the following description.

FIG. 2 illustrates the feeding device 9 in a completely raised state, where it does not touch the collar 5. FIG. 3 shows it in the completely lowered state, characterised by an expansion of the docking device 29 downwards, which makes it reach the collar 5 with a compression force, and by a lowering of the sheath 16, which projects its lower end into the neck 3 of the can 1; the drive device 20 is also lowered, and the oblique section 15 is inclined downwards by approaching the sheath 16; for this it is hinged via a ball joint 30 to the overflow unit 19, and to a horizontal pivot 31 mounted at a fixed location of the feeding device 9, at its opposite end. The state in FIG. 2 corresponds to the phases for changing the can 1, that the feeding device 9 releases; and the state in FIG. 3 corresponds to the vitrification operation phases, where sealing is performed between the feeding device 9 and the can 1.

The sheath 16 is shown in FIGS. 4 and 5. It has a helix 32 on the outer face of its cylindrical wall, the coils of which are significantly inclined and far enough apart from one another. Its upper end has an inlet funnel 33 the upper face of which is a flat collar 34. The wall of the sheath 16 is double and cooled by fluid circulating in pipes 35 (shown in FIG. 5) forming an inner cooling cavity, and which open a little below the funnel 33 into a water box 36 that sealingly surrounds the portion of the sheath 16 located at this height. As the sheath 16 rotates about itself but the water box 36 is fixed in rotation, a permanent circulation of the coolant is maintained by providing the water box 36 with a water inlet chamber 37 and with a water outlet chamber 38 that are both circular but at different altitudes, and wherein the inlet 98 and outlet ends 99 of the pipes 35, at corresponding altitudes, constantly open. The sheath 16 is maintained by a first toothed eccentric 39 of horizontal axis while being rotatable about itself therein, and it extends downward by passing through a hole 40 of the first toothed eccentric 39. The sheath 16 finally has a toothed wheel 41 that extends around its outer face, and a crown 95 a little above the toothed wheel 41, with which it is concentric. If however, the toothed wheel 41 is attached in relation to the sheath 16, the crown 95 is connected thereto by a bearing 96 and may therefore rotate about itself. In addition, the crown has axes 97 of rotation of the toothed pinions 42 (shown in FIG. 8) that mesh with the toothed wheel 41. Bearings 100 are disposed between the first toothed eccentric 39 and the sheath 16 to ensure that the latter remains centred in the hole 40, and rotates without significant effort in relation to the first toothed eccentric 39.

The drive device 20 is now described by means of FIGS. 6 to 8. It comprises a support 44, supported by a pair of vertical cylinders 45 mounted on the upper portion 22 of the sleeve 10, and that may therefore raise the support 44 and the entire drive device 20 above the sleeve 10 (which is illustrated in this figure and corresponds to the raised state of the sheath 16 illustrated in FIG. 2), or lower the support 44 by placing it on the top 46 of the sleeve 10 (which corresponds to the lowered state of the sheath 16 illustrated in FIG. 3); small guide columns 47, vertical and attached under the support 44, maintain its horizontal position by sliding in holes of a collar 48 equipping the top 46.

The support 44 has a toothed crown 49, a first motor 50, and the overflow unit 19, which are attached thereto; it also has the first toothed eccentric 39 by means of a drive ring 101, and a second toothed eccentric 51, having the same features of dimension and or toothing as the first toothed eccentric 39, coaxial and parallel thereto, and provided with a shaft end 52 rotating in a cylindrical housing 102 established on a top face 53 of the overflow unit 19. The shaft end 52 is supported by a bottom face 103 of the cylindrical housing 102. The swirler 18 is suspended to the second toothed eccentric 51 and attached to it (shown in FIG. 10), and it extends through the overflow unit 19 by passing through a hole 54 of the top face 53, then it extends into the sheath 16. The second toothed eccentric 51 also has a second motor 55, which drives the swirler 18 in rotation by a gear 56 (FIG. 2). The first motor 50 drives the slewing ring 101, of vertical axis of rotation, and the first toothed eccentric 39. The latter 39 meshes with a first drive pinion 58 of vertical axis, and it also drives a second drive pinion 59 above the preceding, similar and joined to the latter by a vertical synchronisation shaft 60. With the exception of the worm 57, all of the pinions and other toothed mechanisms have axes of rotation parallel with one another and with the axes of the sleeve 10 and of the sheath 16, that is to say vertical. As the drive pinions 58 and 59 are identical and superposed, and the toothed eccentrics 39 and 51 are also identical and superposed, the rotations of the first motor 50 produce identical circular orbital movements for the sheath 16 and its swirler (“pigtail”) 18, which therefore moves them in unison in the sleeve 10, the swirler 18 remaining centred in the sheath 16. The orbit of the movements maintains the sheath 16 adjacent to the inner face of the sleeve 10, which scrapes it and removes the deposits of materials that foul it. In addition, the rotation of the toothed pinions 42, which mesh both with the toothed wheel 41 attached to the sheath 16 and with the toothed crown 49 (FIG. 8), imposes a rotation of the sheath 16 about itself jointly with the orbital movement, which increases the scraping thanks to the helix 32, which makes the deposits scraped along the sleeve 10 go down.

The orbital movement of the sheath 16 imposes certain measures to maintain the sealing. FIG. 9 illustrates that the sheath 16 is surrounded by an outer collar 61, which is retained in a horizontal rabbet 104 inside the collar 48 by being able to slide therein horizontally: it slides on a horizontal flat bearing surface 62 established around a central hole 105 of the collar 48, distinctly wider than the sheath 16, and it is covered by a hold-down plate 63 that retains it on the flat bearing surface 62 and delimits the rabbet 104 with the latter, by thus forming a sealing plate. Seals 64 are added between the outer collar 61, the flat bearing surface 62, the hold-down plate 63 and the sheath 16. In addition, FIG. 10 shows a similar layout under the overflow unit 19, with the flat collar 34 of the funnel 33 sliding in a flat and circular rabbet 65 established between two thicknesses of a bottom face 66 of the overflow unit 19, seals 67 also being placed between the flat collar 34 and the flat faces opposite the rabbet 65. Moreover, the bottom face 66 is attached to a support post structure 68 belonging to the support 44 and that makes it possible to raise the overflow unit 19 above the gears for setting in motion the sheath 16. FIG. 10 also shows numerous details of neighbouring parts of the device, particularly of the drive unit 20; it also shows circuits for cooling the main tube of the sleeve 10, which comprise water inlet and outlet pipes, 110 for the upper portion 22 and 111 for the lower portion 21, which open into cooling cavities, 112 for the upper portion 22 and 113 for the lower portion 21, consisting of double cooling shells; these cooling circuits are completely separate.

FIGS. 2, 3, 11 and 12 help to describe the docking device 29. It surrounds the lower portion 21 of the sleeve 10, and it is attached to it by a ring support 69. Screw jacks 70 are supported by the ring support 69, and they suspend a docking sleeve 71 sliding along the sleeve 10 in the direction of its axis. In the state in FIG. 2, the docking sleeve 71 is raised; in that of FIG. 12, corresponding to the lowered state in FIG. 3, it is lowered, a docking flange 72 that constitutes its lower end is joined to the top flange 5 of the can 1, and the flanges 5 and 72 may be held against one another by clamping a clamp 73 disposed around the docking flange 72. The sleeve 10 itself does not change altitude between these two states, but the docking sleeve 71 extends it downwards by a variable height. The docking sleeve 71 comprises an elastic portion 74 consisting of a bellows, which absorbs the compressions caused by the excessive lowering of the docking sleeve 71 beyond the contact with the top flange 5 of the can 1, and by the thermal expansions of the can 1 during the vitrification operations. The clamp 73 is supported by static tie rods 75 extending vertically along the elastic portion 74.

The following figures are now considered to discover other layouts combating the fouling of the portions of the feeding device 9. FIG. 13 shows that the sheath 16 contains a tube 76 that passes through it by extending over its entire height in its cooling cavity, from the water box 36 up to the lower edge 77, of the sheath 16 from where it can project rinsing water downwards. The device also comprises an end fitting 78 of the water box 36, and a circular feeding chamber 79, hollowed into the water box 36 at an altitude other than the preceding. It should be noted that this device is used, in the absence of rinsing, as a pressure intake inside the can 1, by connecting a measuring apparatus to the end fitting 78.

FIGS. 14 and 15 illustrate a device associated with the second feed line 24. The extension 28 contains a scraping ram 80, which consists of a piston at the end of the rod of a cylinder 81. The ram 80 remains in the extension 28 in the idle state, but it slides in the downward oblique section 27 when the rod of the cylinder 81 is deployed, by rubbing against its wall or at least by passing against it, which removes the dirt that fouls it. The ram 80 and the rod of the cylinder 81 are in addition cleared by a rinsing pipe 82, connectable to a pressurised water supply apparatus and used if necessary to rinse the downward oblique sections 24 and 27.

FIG. 16 indicates that the docking device 29 may be provided with tubes for injecting air 83 into a gap between the sheath 16 and a docking sheath 84 sliding thereon. The docking sheath 84 belongs to the docking sleeve 71, of which it forms an upper portion, and it guides its vertical sliding movement. The annular gap is closed by circular seals 85 located at its top and bottom ends. The overpressure that establishes in the gap impedes the entry of impurities deposited on the sheath 16 in this gap when the docking sheath 84 lowers, and therefore reduces the risks of blockage.

The bellows 74 is retained between an upper flange 86 and a lower flange 87, best shown in FIG. 17. The volume 106 that it encloses around the sleeve 10 must also favourably be guaranteed against dirt. An air injection tube 88 passes through the upper flange 86 to create an overpressure in this volume 106. Water injection holes 89 also pass through it, and water discharge holes 91 pass through the lower flange 87. The water injection holes 89 are distributed around the circumference of the upper flange 86, and they extend from water boxes 90 hollowed at the top of the upper flange 86 up to a conical clearing 107 located under the upper flange 86, while being guided downwards and radially inwards. The water discharge holes 91 also have a radial and vertically oblique orientation, and they go down from a bottom of the volume 106 to an interior of a funnel 108 that forms the bottom of the docking device 29, and that ends at the docking flange 72. The overpressure produced by the injection of air largely prevents the dirt carried upwards by the fumes from entering into the volume 106. In addition, the water injected radially inwardly bounces against the outer face of the sleeve 10 and coming out of the water injection holes 89, disperses in the conical clearing 107 then in the entire volume 106, before flowing into the funnel 108 either directly, or by following the water discharge holes 91.

The invention is also compatible with the taking of measurements during the operations of vitrification or of other treatments. A possibility of a pressure intake through the sheath 16 has already been encountered. Another possibility relates to viewing the content of the can 1 and for example its level. FIG. 18 shows a sight tube 92 that obliquely passes through the upper flange 86 and is guided into the gap between the bottom of the sleeve 10 and the docking sleeve 71; the sight passes through a local notch 93 of the sleeve 10; the viewing direction subsequently extends through the neck 3 and leads into the can 1. The measurement is carried out for example by a laser 114, by leaving the sight tube 92 closed by a transparent porthole 94, behind which the laser 114 is installed; its beam 115 is directed in the axis of the sight tube 92; the latter is flushed by an injection of overpressure gas, introduced by a pipe 116 that connects to the inside of the sight tube 92 below the transparent porthole 94, to keep it free of fumes.

The equipment for injecting and discharging the fluids, as well as the measuring means envisaged, are considered as known and therefore are not described in detail here.

Claims

1. Device for feeding a container for an installation for the heat treatment and conditioning of waste, comprising a sleeve having a lower opening to be docked with an upper opening of the container, a first line for feeding the waste to be treated connecting to the sleeve and penetrating therein, the sleeve containing a tool for scraping its inner face, wherein the scraping tool is a sheath of axis parallel to the sleeve and forming a terminal section of the first feed line, and the device comprises a support of the sheath, the support being provided with a motorised off-centring mechanism to which the sheath is suspended, the off-centring mechanism moving the sheath in orbits where it is adjacent to the inner face of the sleeve.

2. Device for feeding a container according to claim 1, wherein the sheath extends beyond the sleeve in a direction opposite the lower opening, through a sealing plate at the upper end of the sleeve, the sealing plate comprising a movable plate linked to the sheath, and a fixed plate linked to the sleeve and on which the movable plate moves, the fixed plate being provided with an opening for passage of the sheath that is larger than the latter, and a sealing device between the fixed plate at the movable plate.

3. Device for feeding a container according to claim 1, wherein the off-centring mechanism comprises a toothed gear wheel to which the sheath is suspended, without being coaxial to an axis of rotation of said toothed wheel.

4. Device for feeding a container according to claim 1, wherein the off-centring mechanism is arranged to also make the sheath rotate about itself.

5. Device for feeding a container according to claim 3, wherein the off-centring mechanism comprises a gear between a toothed wheel attached to the sheath and a toothed ring attached to the off-centring mechanism, and the sheath is rotatably mounted in the toothed gear wheel to which it is suspended.

6. Device for feeding a container according to claim 4, wherein the sheath has a helical excrescence, particularly a helical blade, on its outer face.

7. Device for feeding a container according to claim 1, wherein the first feed line contains at least one rotating swirler, particularly of the “pigtail” type, to advance the waste to be treated.

8. Device for feeding a container according to claim 2, wherein the swirler extends beyond the sheath in the direction opposite the lower opening of the sleeve, is suspended to a second motorised off-centring mechanism to which the sheath is suspended, and is rotated by a motor mounted on the second off-centring mechanism.

9. Device for feeding a container according to claim 8, wherein the off-centring mechanism to which the sheath is suspended and the second off-centring mechanism are mechanically connected to one another and driven by the same motor.

10. Device for feeding a container according to claim 2, wherein the first feed line comprises an upstream section, forming an angle with the terminal section and connected to the terminal section by an overflow unit, the terminal section being provided with a funnel at its top, which is connected to a pierced lower face of the overflow unit, the sheath being movable under the overflow unit.

11. Device for feeding a container according to claim 10, wherein the sheath is sliding in an axial direction of the sleeve, and the upstream section is tilting by being hinged, at its two ends, to a fixed point of the device and to a wall of the overflow unit.

12. Device for feeding a container according to claim 10, wherein the upstream section is equipped with a motorised rotating swirler, and connected, at an end opposite the overflow unit, to a hopper for pouring the waste to be treated.

13. Device for feeding a container according to claim 1, wherein it comprises a second feed line made of material of a matrix for conditioning the waste, opening into the sleeve.

14. Device for feeding a container according to claim 13, wherein the sleeve consists of two portions in extension, that can be dismantled from one another and equipped with different coolant circuits, a lower portion of which comprising the lower opening, and an upper portion into which the second feed line and a line for discharging gaseous products from heat treatment open.

15. Device for feeding a container according to claim 1, wherein the second feed line is equipped with a scraper of its inner face.

16. Device for feeding a container according to claim 15, wherein the scraper is a ram sliding in a section of the second feed line adjacent to the sleeve, and housed in an extension of said section of the second feed line, beyond an upstream section of the second feed line forming an angle with said section adjacent to the sleeve.

17. Device for feeding a container according to claim 16, wherein a hole and a rinsing liquid pipe pass through the ram.

18. Device for feeding a container according to claim 1, wherein the sleeve comprises a main rigid tubular portion and a docking device, the docking device comprising a docking sleeve surrounding the main portion by extending downwards, comprising the lower opening of the sleeve, mounted on the main portion and movable along the main portion.

19. Device for feeding a container according to claim 18, wherein the docking sleeve comprises a compressible portion in the direction of the mobility of the docking sleeve.

20. Device for feeding a container according to claim 18, further comprising a means for rinsing an annular volume between the docking sleeve and the main portion of the sleeve.

21. Device for feeding a container according to claim 19, further comprising a means for rinsing an annular volume between the docking sleeve and the main portion of the sleeve, wherein the compressible portion is a bellows, and the rinsing means comprises inlet pipes in the annular volume that overhang the bellows, guided radially towards the main portion of the sleeve and producing bounces of rinsing liquid radially outwardly and towards the bellows.

22. Device for feeding a container according to claim 18, wherein it comprises a pipe for injecting overpressure gas into an annular volume between the docking sleeve and the main portion of the sleeve.

23. Device for feeding a container according to claim 18, wherein the docking sleeve comprises a docking sheath sliding on the main portion of the sleeve, and actuators for moving the docking sheath connecting the docking sheath to the main portion of the sleeve.

24. Device for feeding a container according to claim 23, wherein it comprises a pipe for injecting overpressure gas into an annular volume between the docking sheath and the main portion of the sleeve.

25. Device for feeding a container according to claim 1, further comprising a pressure intake pipe comprising rinsing means, extending in a wall of the sleeve along the sleeve, and opening at a lower edge of the sleeve.

26. Device for feeding a container according to claim 1, further comprising a means for measuring the filling level of the container, disposed through the sleeve with overpressure gas injection into the pipe.