Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J19/32—Packing elements in the form of grids or built-up elements for forming a unit or module inside the apparatus for mass or heat transfer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/322—Basic shape of the elements
  • B01J2219/32203—Sheets
  • B01J2219/3221—Corrugated sheets
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/322—Basic shape of the elements
  • B01J2219/32203—Sheets
  • B01J2219/32224—Sheets characterised by the orientation of the sheet
  • B01J2219/32234—Inclined orientation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/322—Basic shape of the elements
  • B01J2219/32203—Sheets
  • B01J2219/32237—Sheets comprising apertures or perforations
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/322—Basic shape of the elements
  • B01J2219/32203—Sheets
  • B01J2219/32255—Other details of the sheets
  • B01J2219/32262—Dimensions or size aspects
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/322—Basic shape of the elements
  • B01J2219/32203—Sheets
  • B01J2219/32265—Sheets characterised by the orientation of blocks of sheets
  • B01J2219/32272—Sheets characterised by the orientation of blocks of sheets relating to blocks in superimposed layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/332—Details relating to the flow of the phases
  • B01J2219/3322—Co-current flow
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/332—Details relating to the flow of the phases
  • B01J2219/3325—Counter-current flow

Definitions

• the present invention relates to a strip of sheet material, in particular sheet metal, for a packing module for processing a liquid, of the type comprising corrugations, when the strip is arranged in a generally vertical plane with its horizontal edges, have an orientation generally inclined with respect to a general direction of circulation of said liquid, substantially vertical, and comprising openings of generally elongated shape having edges extending in the general direction of the opening.
• packing is intended to mean a device intended for mixing a phase and / or for bringing several phases flowing in co-current or counter-current into contact.
• heat and / or material exchange and / or a chemical reaction can take place.
• a particular application of the invention resides in the columns separating gas mixtures, in particular the air distillation columns.
• modules also called “packs”, of corrugated-cross packing.
• the modules include corrugated sheets arranged vertically, sheets whose corrugations are oblique with respect to a general direction of circulation of fluid in the installation, and inclined alternately, generally crossed by 90 °, from one sheet to the other.
• the packing modules are threaded into the distillation column so that the sheets of a module are angularly offset from the sheets of an adjacent module around the axis of the column, generally 90 ° from one module to another.
• openings which are formed in the sheets have been proposed in the state of the art. These openings lead to a change in the flow of gas from one side to the other of the lining sheet and improve the exchange with the liquid.
• the object of the invention is to propose packings which allow an improved exchange between the liquid and the gas.
• the subject of the invention is a strip of the aforementioned type, characterized in that the openings comprise, from their low point, a lower region whose edges, over at least 75% of their total length, are extend in a direction which forms with the natural flow direction of the liquid at each corresponding point an angle between 0 ° and 20 °, especially between 0 ° and 10 °.
• the strip may include one or more of the following characteristics:
• edges of said lower region extend over at least 90% of their total length in a direction which forms said angle between 0 ° and 20 °, especially between 0 ° and 10 °;
• edges of said lower region extend over their total length in a direction which forms said angle between 0 ° and 20 °, especially between 0 ° and 10 °; the edges of the entire periphery of the openings extend in a direction which forms said angle of between 0 ° and 20 °, in particular between 0 ° and 10 °; -
• the openings are triangles whose tip formed by the two longest sides is directed substantially in the direction of natural flow of the liquid; said openings have dimensions such that they avoid overlapping by a film of said liquid; the direction of the edges of said openings, at least in said lower region, is substantially parallel to the direction of natural flow of the liquid over the surface of the strip in the vicinity of the edges of the opening;
• the strip has smooth surfaces so that the natural direction of flow of the liquid is, on these surfaces, the direction of greatest slope of the strip;
• the distance (p_) between two ridge (36) or valley (38) lines of the partial strips (34) measured in the direction of the edge (40) of the strip (24) is identical over the entire surface of a current region (28) of the strip, and in that the strip reproduces identically when it is shifted in the direction of the edge, by a distance N xp ', with and preferably 4>N> 1 .
• the strip comprises, in its current region, openings arranged at a distance of a submultiple of said distance, in particular half of this distance, in the direction of the horizontal edge of the strip; -
• the folding angle of the undulations of the partial strips, the height of these undulations, the radius of curvature and the inclination of these undulations relative to the edge are identical over the entire surface of the strip;
• the strip includes first and second partial wavy strips adjacent and offset from each other, in particular by a half-wave pitch, the partial strips have different directions of natural flow of the liquid each others ; the edges of said openings of the partial strips extend in an intermediate direction between said directions of natural flow of the liquid, in particular substantially parallel to the bisector of the two directions; said openings consist of flaps folded out of the plane of the strip, flaps which are defined by a curved slot formed in the strip; said openings consist of bosses formed on one side of a slot, in particular in the form of a partial cone or in the form of a partial cylinder; said openings are constituted by twisted parts extending between two parallel slots; said openings are constituted by re-entrant folds which extend on one side of a slot which crosses the crest of a fold of the strip; said openings are slits which cross the crest of a fold of the strip, this in order to avoid a concentration of liquid in the bottom of the waves
• the strip comprises at at least one of its upper or lower regions means for spreading liquid transversely to the main direction of flow of fluid, in particular streaks or perforations formed in the strip;
• the packing strip is devoid of said openings in said upper and / or lower region;
• the strip comprises, in its upper and / or lower region means for reducing pressure drop.
• the subject of the invention is also a packing module for a material and / or heat exchange column, characterized in that it comprises a stack of strips as defined above with their directions of undulation corrugated d 'one strip to the next.
• the invention further relates to a material and / or heat exchange installation comprising at least one packing module as defined above and a liquid distribution device on the upper surface of the module.
• the liquid distribution device comprises a distributor and / or a packing module promoting the spreading of the liquid transversely with respect to the main direction of flow.
• FIG. 2 is a schematic longitudinal sectional view of a material and / or heat exchange column comprising packing modules according to the invention
• FIG. 3 shows the detail III of Figure 2 on a larger scale
• - Figure 4 is a sectional view along the line IV-IV of Figure 3;
• FIG. 5 is a perspective view of the detail shown in Figure 3;
• - Figure 6 is a plan view of a blank used for the manufacture of the trim strip portion of Figure 3;
• Figures 7A to 7H show perspective or side views of alternative openings made in packing strips according to the invention;
• FIG. 8 is a side view of a variant of a packing strip according to the invention.
• FIG. 1A a smooth plate P has been shown inclined at an angle relative to the vertical (gravity force F p ). A liquid flows on the upper surface of the plate.
• the plate P has a direction of greatest slope G defined by the section of the surface of the plate with a vertical plane perpendicular thereto.
• the plate P When the plate P is supplied with liquid, the latter flows in a natural direction S of flow, which coincides in the case of this plate with smooth surface P with the direction of the greatest slope G.
• Two rectangular slots FI and F2 are provided in the plate P.
• the respective longitudinal edges Bl and B2 of the slots Fl and F2 define angles ⁇ , respectively ⁇ , with the direction of greatest slope G.
• the angle ⁇ is greater than one liquid takeoff angle from the edge of a slit, while the angle ⁇ is less than this.
• the take-off angle of the liquid depends on the viscosity of the liquid and the material of the plate. Because the angle ⁇ is greater than the take-off angle of the liquid, the liquid drips from the edge Bl of the slot FI and creates a dry zone Z downstream of this slot. In this zone Z an exchange of heat and / or material between the liquid and a gas is not possible. On the other hand, thanks to the small angle ⁇ , that is to say less than the take-off angle of the liquid, the liquid flows around the edges B2 of the slot F2 and covers the part of the plate located at downstream of this slot. Consequently, an exchange between a gas and liquid takes place at this location.
• the angle ⁇ is 0 °, that is to say that the edges of the slot F2 extend parallel to the direction of natural flow of liquid.
• the angle ⁇ can be between 0 ° and 20 °, in particular between 0 ° and 10 °.
• FIG. 1B there is shown a plate P 'arranged in the same way as the plate P.
• This plate P' has oblique grooves relative to the horizontal.
• the direction S 'of natural flow of the liquid flowing on this plate P' differs from the direction of greatest slope G of this plate P 'by an angle ⁇ .
• the flow of the liquid is diverted towards the direction of the streaks.
• the longitudinal edges Bl 'of the slot FI' also form an angle ⁇ with the natural direction of flow of the liquid S '. Consequently, a dry zone Z 'is created downstream of the slot FI'.
• the slot F2 ′ and its longitudinal edges B2 ′ extend along the angle ⁇ with respect to the direction S ′ of natural flow of the liquid.
• FIG. 2 there is shown a material and / or heat exchange column 2 according to the invention with a general vertical axis XX.
• Column 2 comprises, at its upper end 4, a liquid inlet 6, opening into a distributor 8 which distributes the liquid over the cross section of column 2, as well as a vapor outlet 10.
• the column 2 further comprises a cylindrical shell.
• a packing module 18 which promotes spreading of the liquid transversely to the axis XX is arranged in the shell V directly below the dispenser 8.
• Such a module 18 is known per se, and is for example a packing module comprising corrugated-cross filling with perforations or ridges.
• a plurality of lining modules 20 is arranged in the shell V below the module 18.
• a lower support 22 holds the lining modules 18, 20.
• Each lining module 20 comprises a multitude of corrugated strips of lining 24.
• the strips 24 are each arranged parallel to a general direction D f of fluid circulation in the column 2, namely vertically, and one against the other.
• Each strip 24 comprises regions extending horizontally, one above the other, upper 26, upper transition, current 28, lower transition 30 and lower 32.
• part of a strip of lining 24 in side view namely a part of the current region 28, the lower region 32 as well as the lower transition region 30.
• the current region 28, in side view, consists of a succession of partial bands 34 of general direction Di inclined with respect to the vertical (D f ).
• Each partial strip 34 consists of flat surfaces connected alternately by crest lines 36 and valley lines 38.
• the lines 36, 38 have the same inclination Di which is, in this case, substantially 45 ° relative to the edge lower 40 of the lining strip 24.
• the ridge 36 / valley lines 38 of a partial strip 34 extend the valley 38 / ridge lines 36 of the two adjacent partial strips 34.
• Each partial strip 34 is separated by a row 42 of openings 44, rectilinear in side view.
• Each opening 44 crosses the junction of a crest line 36 of a partial strip 34 and the valley line 38 of the adjacent partial strip 34.
• the openings 44 of the same row 42 are offset from one opening 44 to the next, in the direction D l ⁇ by a small distance d, defining crosspieces 46 or connecting lines between two adjacent partial strips 34.
• the openings 44 are arranged parallel to each other at a distance a '. This distance a 'is, measured in the direction of the horizontal edge 40 of the strip, half the distance p' between two successive peak lines 36.
• each partial strip 34 of the current region 28 has a succession of approximate diamonds 48 inclined alternately forward and backward of the plane of FIG. 3.
• Two successive approximate diamonds 48 form an angle of 60 ° between them, in end view (see Figure 4).
• the lower transition region 30 has openings 44 identical to those of the current region 28. As a difference, the openings 44 have a distance i relative to each other, in the horizontal direction, which is twice the distance a 'from openings 44 of the current region 28 therebetween. In other words, one opening 44 out of two is eliminated.
• the lower region 32 as well as the upper region 26 consist of a corrugated part of the packing strip devoid of openings.
• the surface of this region consists of extensions of the diamond surfaces 48 of the transition regions.
• the lining strips 24 are arranged one against the other so that the lines of valleys 38 and ridges 36 of a strip are offset by substantially 90 ° relative to to those of an adjacent strip 24, that is to say that their directions Di are inclined by substantially 45 ° in one direction and in the other with respect to the direction Df from one strip 24 to the other.
• each opening 44 extends, in side view, in a direction D 0 inclined at 59 ° relative to the horizontal, which corresponds, for an angle of 60 ° between two approximate diamonds 48 and for a 45 ° direction of the ridge / valley lines of a smooth strip 24, in the direction S of natural liquid flow, therefore, for the example given, in the direction of greatest slope G in FIG. 1A.
• Liquid flowing over the surface of the strip 24 therefore flows substantially parallel to the edges 50 of the openings 44. Consequently, the creation of dry zones downstream of the openings 44 during the flow of the liquid is greatly reduced, or avoided.
• the modules 20 according to the invention therefore have an effective exchange surface between gas and large liquid.
• Each opening 40 leads to a sectioning of the gas flow and to the creation of turbulence increasing the exchange efficiency of the lining.
• each opening 44 has a large dimension, so that it leads to a low pressure drop.
• the direction of the edges must be sufficiently close to the direction S of natural flow of the liquid to avoid dripping of the liquid from the edges.
• the possible tilt is generally between 0 ° and
• the inclination with respect to the vertical of the surfaces is identical at each point of the packing strip 24. Consequently, the direction S of natural flow of liquid is also identical at each point of the strip 24.
• the edges of the openings must extend so that at each point of the edge of the opening, the direction of the tangent to the edge at this point is close to the direction S of natural flow of the liquid at this point of the strip, or preferably identical to this direction.
• the strip 24 is made of sheet metal from a flat blank 24A.
• FIG. 6 a part of this blank is shown. This part is used for the manufacture of the part of the strip 24 of FIG. 3.
• the references of the blank correspond to the references of the corresponding parts of the filling strip 34, with an A added.
• This blank is a thin, smooth and flat sheet.
• the blank 24A comprises a current region 28A, comprising columns 42A of slots 44A.
• Each slot 44A is a rectilinear slot and arranged perpendicularly by relative to the lower edge 40A of the blank 24A.
• Each slot 44A extends from an area located midway between two future ridge 36A and valley lines 38A (indicated in dotted lines in Figure 6) through one of these future lines 36A, 38A into an area located midway between future valley lines 38A / ridge 36A adjacent.
• the slots 44A of a vertical row 42A are offset from one to the next, in the direction of the future ridge 36A or valley 38A lines, by the aforementioned distance d.
• the slots 44A of a row 42A are arranged, with respect to the slots 44A of the row 42A, adjacent to a distance a which corresponds to half the distance p between two future lines of ridges 36A (or of valleys 38A), measured along the edge 40A.
• the slots 44A of two adjacent rows 42A are arranged at identical distances from the edge of the plane.
• the slots 44A of the blank constitute horizontal rows 56 parallel to the edge 40A.
• Two rows 56 are separated by a connecting zone 58 devoid of slots 44A.
• the blank 24A further comprises a transition region 30A which has a horizontal row 60 of slots. In this region, one in every 44A slot is eliminated.
• the lower row 56 of the current region 28A and the row 60 are separated by a connection zone 62 without a slot, similar to the connection zones 58.
• the blank 24A further comprises a solid lower region 32A which is smooth and flat and which corresponds to the lower region 32 of the filling strip. Consequently, the periodicity of the slots 44A of the current region 28A of the blank is identical to the distance of future ridges 36A / valleys 38A p_, and the cutting and folding tool used for manufacturing the strip 24 can be particularly simple. In general, slots 44A are arranged at a distance corresponding to a small integer multiple N of the distance between peak lines, for example up to 4.
• the manufacturing of the filling strip from the split blank 24A is carried out by folding with a folding angle of 60 °, with advancement of the strip in successive steps, by means of strips of suitable configuration. Due to this folding, the slots 44A open accordingly, and form the openings 44 (see Figures 4 and 5). By this folding at 60 °, the ridge / valley lines are placed at an angle of 45 ° relative to the horizontal.
• FIGS 7A to 7H there are shown different embodiments of openings 70A to 70G formed in a packing strip according to the invention.
• FIG. 7A shows a flap 74 made from a slightly curved slot, in particular in an arc of a circle, and pushed back outside the plane of the strip according to a cord 76 substantially parallel to the natural direction of flow S of the liquid.
• Figure 7B shows an opening 70B formed by a boss 78 stamped in the form of a partial cone on one side of a straight slot 71B substantially parallel to the direction S.
• Figure 7C shows five parallel openings 70C of identical length, substantially parallel to the direction S, formed in the trim strip. The four zones extending between the openings are twisted around an axis parallel to the openings by forming louvers 80.
• Figure 7D shows two openings 70D formed by two parallel slots 71D of identical length, substantially parallel to the direction S, between which extends a stamped boss 82 of partially cylindrical shape.
• Figures 7E and 7F show a folded portion 84 of a trim strip. A slit is formed obliquely through the crest 86 of the fold and the strip has on one side of the slit a re-entrant fold 88 forming an opening 70E. The re-entrant fold 88 has a decreasing depth and extends to a point 71E distant from the opening 70E.
• this part includes two openings 70G made from two parallel oblique slots of identical lengths.
• the part 90 of the strip lying between the two slots forms a re-entrant fold of constant depth.
• FIG. 8 there is shown a variant of a packing strip according to the invention.
• This lining strip 100 is made up of first and second alternating partial strips 102, 104, wavy and parallel, with different wave steps, measured along the edge of the strip.
• the undulations 106, 108 of the strips 102, 104 are inclined relative to the horizontal, in the mounted state of the strip, at different angles. Consequently, the first partial strips 102 have a natural direction of flow of liquid Si which differs from the natural direction of flow of liquid S2 from the second partial strips 104 (FIG. 9).
• the undulation of a partial strip 102, 104 is offset by a half notch with respect to an adjacent partial strip 104, 102, so that valleys of a partial strip 102, 104 lie opposite each other. screw crests of a neighboring partial strip 104, 102.
• the partial strips 102, 104 form openings 109 therebetween.
• edges 110, 112 of the partial strips 102, 104 are rectilinear and arranged parallel to the mean direction SM of the directions S1 and S2 of natural flow of liquid of the first and second partial strips 102, 104.
• This mean direction of flow SM is intermediate between the two directions
• SI, S2 flow and is preferably identical to the bisector of these two directions.
• This packing strip 100 increases the turbulence of the gas and therefore the exchange efficiency between the gas and the liquid while substantially totally avoiding the creation of dry zones.
• the strip 100 can be produced by welding the partial strips to one another, or by cutting and folding a solid blank by means of two sets of folding strips.
• a packing module which comprises a packing strip according to the invention may comprise at its upper and / or lower part means for spreading the liquid transversely to the general direction of flow.
• These spreading means can be formed by striations or perforations formed in the corresponding part of the strip (such as the upper 26 or lower 30 regions of the strip 24), this part being, in this example, devoid of the openings such as 52, 54 of the current region 28 of the strip.
• the linings according to the invention result in a large contact surface of the liquid with the gas, while allowing turbulence and cutting off the flow of the gas and substantially preventing any creation of dry zones.
• the columns having packings according to the invention have a low packing volume and a low cost, for a given treatment throughput.
• the lower region of the openings extends at an angle ⁇ between 0 ° and 20 ° relative to the natural direction of flow of the liquid.
• ⁇ the angle between 0 ° and 20 ° relative to the natural direction of flow of the liquid.
• the lower region comprises, for example 90% or 100% of the edges extending along this angle ⁇ -
• the lower region may for example be in the form of a triangle, the point of which formed by two longest sides is directed in the direction of natural flow of the liquid.
• the lower region 32 and / or the upper region 26 can be provided with pressure drop reduction means on the part adjacent to the next packing module.
• Such means are, for example, folds comprising ridges / valleys having an inclination which gradually changes from the inclination of the current region in the vertical direction towards the corresponding lower or upper edge.

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• Chemical & Material Sciences (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Physical Or Chemical Processes And Apparatus (AREA)
• Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

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• 2002
  • 2002-06-27 CN CN02813541.5A patent/CN1274401C/zh not_active Expired - Lifetime
  • 2002-06-27 US US10/482,831 patent/US20040173919A1/en not_active Abandoned
  • 2002-06-27 WO PCT/FR2002/002226 patent/WO2003004148A2/fr active Application Filing
  • 2002-06-27 EP EP02751289A patent/EP1417028A2/fr not_active Ceased
  • 2002-06-27 JP JP2003510152A patent/JP4634033B2/ja not_active Expired - Fee Related
  • 2002-06-27 CA CA002451830A patent/CA2451830A1/fr not_active Abandoned

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