FR2668961A1 - PROCESS AND DEVICE FOR THE SEPARATION OF CONSTITUENTS OF DIFFERENT SIZES FROM A MIXTURE OF SOLIDS. - Google Patents

Abstract

For separating pieces of metal wire, pins, etc. from a mixture of solids (15) previously sieved through sieve holes of less than 20 mm, the mixture of solids (15) containing pieces of metal wire oriented in the direction of transport is brought to a conveyor (1 ) endless up to an empty space (16) which, on the transport path, is located immediately after the endless conveyor (1) so as to allow the passage of granular materials and whose opening width is smaller than the smallest length of wire to be separated. This makes it possible to separate the pieces of metal wire contained in the mixture of sieved metal wire which have a length reaching 70 mm and exceeding 20 mm, from a mixture of non-ferrous metals already separated from the non-metallic fraction or from a mixture of solids (15) containing both non-metallic fractions and non-ferrous metals.

Description

The invention relates to a method and a device.

  for the separation of constituents of different sizes

  annuities of a mixture of solids, especially mixtures

containing non-ferrous metals.

  To recover non-ferrous metals, which have a

  great value, it is known to produce a magnetic field

  than alternative, for example by means of an inductor or

  by means of a magnetic rotor, and to realize the separation

  tion, known as eddy currents, of non-magnesium metals

  ticks good conductors of electricity In this operation, the product to be treated passes, for example on a conveyor belt or in free fall, in front of the poles

  of a generator producing an alternating magnetic field.

  Eddy currents are induced in the constituents.

  ants of the mixture to be separated which are conductive of the elect

  tricity and produce their own magnetic fields which are oriented in the opposite direction of the generator field and, therefore, due to electromagnetic forces, accelerate the constituents in question relative to

  other constituents of the mixture Separation by cou-

  rants de Foucault makes it possible to separate non-ferromagnetic substances which conduct good electricity, such as aluminum and copper, from mixtures of non-ferrous solids and mixtures of solids composed of non-ferrous metals and non-metallic substances, such as automobile waste containing fibers, scrap from electronic devices or similar materials Where these mixtures contain ferromagnetic parts, the separation plant

  by eddy currents can be associated with an ins-

  magnetic separation plant, located upstream, which

  ensures the prior removal of ferromagnetic substances

  ticks It is also advantageous to place upstream of the eddy current separation installation

  other sorting and classification stages, because an enrich-

  2- sation and prior fractionation as far as possible of the mixture of solids arriving have a positive action on the separation efficiency and on the flow

  of the eddy current separation installation 8.

  During the classification by preparative sieving of a mixture of solids subjected to a primary grinding, in particular during the sieving of a fraction of the mixture having a particle size less than 20 mm, numerous pieces of thin metallic wires from 30 to 70 mm long coming from cables or similar origins pass

  also through the 20 mm sieve holes or di-

  lower mensions These pieces of metal wire are obviously also constituted by high-value non-ferrous metal to be recovered, generally by copper, and are, when they pass through an eddy current separator described by patent DE OS 39 09 499, which comprises a crown plate penetrating into the turbulence zone of the magnetic field generator, entrained with the fraction constituted by non-earth metals; however, during the subsequent classification of the mixture of non-ferrous metals in a separation facility in dense medium and by flotation, the pieces of metal wire constitute a gene These pieces of metal wire, which have a length of about 30 to 60 mm , have the drawback, in the separation installation in dense medium and by flotation, of plugging the sieve orifices and the material discharge openings. When in practice the metallic wires constitute

  discomfort for the further treatment of the fraction

  titrated by non-ferrous metals, for example where avoidable, in preparation facilities

  located downstream, in particular in sewer installations

  paration in dense medium and by flotation already mentioned-

  born, incidents due to obstructions, we adopt, in 3 -

  with regard to the results of separation, solu-

  compromises in which one renounces to recover part of the recoverable non-ferrous metals, in particular metallic wires, in favor of a still acceptable proportion of metallic wires in the fraction constituted by non-ferrous metals This is achieved in the case of an eddy current separator, by acting on the conveyor transport speed which brings the mixture of materials to the separator and / or on the position of the separation threshold This compromise however leads to serious drawbacks: on the one hand , loss of non-ferrous metals and, on the one hand, a fraction of

  scrap containing non-ferrous metals in quantity

  so that metallic wires and non-ferrous metals contained in the scrap fraction can

  to be recovered, a separation is required in an installation

  costly separation in dense media and by flow-

  tation to separate the valuable components from the proportionally much larger part which

  is contained in the waste A separation by a new

  sieving calf cannot be considered, because the experiment

  rience shows that most of the metal wires

  thin liquefies 30 to 70 mm long which are contained in a mixed fraction of O to 20 mm would fall back through the

small sieve holes.

  The object of the invention is the development of a method and a device allowing the separation of these metallic wires from a mixture of solids previously screened with a particle size less than 20 mm or from a mixture of ferrous metals from

  this fraction already separated from the non-metallic parts.

  This object is achieved, according to the invention, by the fact that, for the separation of fragments of metal wires, pins or the like from a mixture of solids previously sieved through orifices 4 -

  sieves less than 20 mm, the mixture of solids contains

  ning pieces of metal wire oriented in the direction of transport is brought on a conveyor without

  end to an empty space which, on the trans-

  port, is located immediately after the conveyor without

  fine so as to allow the granular material to pass

  res and whose opening width is smaller than

  the smallest length of wire to separate.

  Under these conditions, for the treatment of a mixture of

  materials subject to prior classification, such as

  lying in a pre-treatment or post-treatment stage

  with a view to separation by eddy currents, the

  pretreatment stage to be understood as consis-

  both in that first of all the metallic wires are

  separated from a sieved mixture of non-fer-

  reux, of wire and scrap and that thereafter the remaining mixture constituted by the nonferrous metals and the rejects is subjected to the separation by eddy currents, when the mixture arrives at the level of the empty space formed on the path of transport, granular components (non-ferrous metals or non-ferrous metals and scrap) of smaller dimensions fall into space

  void in question; on the other hand, the metallic wires do not

  feels above the empty space and, therefore, accumulates

  mule while being separated from the other constituents of the

  diaper. The opening width of the empty space is measured

  relative to the normally curved end of the

  voyeur without finding in the radial direction in relation to the projection area; it is enough that it is slightly

  larger than the dimensions of the largest grain determined

  born by sieving For the orientation of metal wires-

  The device may include, upstream of the

  endless voyeur, a vibrating gutter (vibrating conveyor) provided with longitudinal grooves in which - are placed the metal wires oriented in the longitudinal direction by vibrations The orientation of the metal wires is also ensured by the fact that the mixture of solids is poured from the feed conveyor, located upstream, constituted by the vibrating gutter, on the endless conveyor and that in general the

  two ends of a piece of wire do not come if-

  in contact with the endless conveyor De

  this fact, the end of the wire which comes into contact with the

  the endless conveyor is already conveyed in the direction of transport before the other end of the wire comes into contact with the endless conveyor; the result is that the metal wires are oriented on the endless conveyor Because the speed of the endless conveyor is higher, this effect is even more accentuated, because the ends of the wire which are in contact with the endless conveyor are trained faster Finally, very pointed orientation pieces could penetrate from above into the material flow

  and orient the metal wires without causing

accumulation vouchers.

  In a device allowing the separation of the

  lange of sieved solids in question, the empty space is located between the endless conveyor and a guide plate which is preferably arranged in such a way that the largest granular constituents 3 rd sieved fraction pass directly between the endless conveyor and the sheet

  guide, which ensures sorting Indeed, the wires

  metal evacuated at the end of the endless conveyor does not fall into the empty space located on the path of

  transport, upstream of the guide plate, but crossing

  feels the empty space in front of the sheet metal

  dage and are directed to their point of accumulation which

is located further down below.

  It is advantageous that the guide plate ends 6 - near the projection line of the materials Par

  against, the width of the opening, that is to say the

  tance measured in the radial direction between the curved part of the end of the endless conveyor and the upper edge of the guide plate> depends on the grain size range

  and only slightly exceeds the largest dimension of mor-

  material that can appear The projection line of the materials is reached when the mixture of materials

  granular lines, on a curved line located at the ex-

  end of the endless conveyor, that is to say where it changes direction, to slip or fall away from the conveyor The guide plate ends clearly higher and prevents non-ferrous metals or the non-ferrous metals and the rejects engage in the path of fall of the metallic wires and mix with them Taking into account the speed of transport, the granular constituents fall essentially along the vertical before being able to follow a projection dish or else go hit the side of the sheet metal

  guide which is opposite and rebound By con-

  tre, separate metal wires cannot, because of their length they do not tip over

  only then pass through the opening of the empty space,

  bang smaller than the length of a piece of wire, and fall down; they cross the

  width of the opening of the empty space between the former

  projection end of the endless conveyor and the upper edge of the guide plate and are guided, as on

  a slide, by the guide plate to the location

cement where they accumulate.

  In an endless conveyor whose speed is

  variable preference, it is possible to adapt to the com-

  position of the mixture the transport speed which determines

the projection dish.

  It is advantageous that the endless conveyor has 7 -

  a driven conveyor belt guided on drums

  stock exchange at least at its loading ends

  and discharge The return drum located at the end

  end of the endless conveyor being taken as a point of reference for determining the position

  from the upper edge of the guide plate, this upper edge

  can be clearly above the horizontal axis

  zontal of the deflection drum It is therefore possible, in

  known eddy current separators which include

  carry a conveyor belt rotating on sieves

  purse and an alternating magnetic field generator mounted in the front drum and, in addition, a separation threshold located upstream of the front deflection drum and very high, to achieve, taking into account the knowledge acquired which are the basis of the invention, a device according to the invention allowing a separation of the wires

  metallic because a mixture of already dried materials

  magnetically adorned or a mixture of sieved materials,

  but still including non-ferrous metals and mor-

  scrap of metallic threads and scrap, in a

  separate operation, in the disconnected separator,

  say not producing eddy currents, which of this

  can toeubi Jise - as a metal wire separator.

  Furthermore, unlike what is achieved in known eddy current separators comprising

  a top plate which extends upwards> in the-

  which pieces of metallic wires and non-ferrous metals arrive in the same fraction of the mixture, which the invention is precisely intended to avoid, it is essential that between the endless conveyor and the guide plate the width d opening is small enough to exceed that little (by about 2 mm) the largest known piece (20 mm) of the sieved material mixture

  obtain continuous operation, it is however pre-

  possible to place, downstream or upstream of a separator 8 - known eddy current, a separation device

according to the invention.

  When the guide plate, which is preferably in several parts, can be moved, for example adjusted in inclination or in height and also moved in the horizontal direction, it is possible to easily carry out adjustments adapted to each operating situation. The invention is described below in more detail by means of an exemplary embodiment with reference to the drawing, which makes it possible to highlight

  the characteristics and advantages of the invention.

  Figure 1 is a side view showing diagrammatically

  a metal wire separation device

in a mixture of materials.

  Figure 2 represents, apart, the end of eva-

  cuation of the separation device of figure 1.

  In a preferred embodiment of the invention,

  an endless conveyor 1 consisting of a belt or

  endless conveyor wheel 2 passes, at its loading end 3 and at its discharge end 4, on guide and return drums 5, 6 The

  posterior return 5 which is at the end of the

  gement 3 is fitted with a drive device (drum motor) which allows the speed of

  transport of the conveyor belt 2.

  At its discharge end 4, the conveyor without

  end 1 is followed by a guide plate 7 which is mostly

  parts and includes a support frame 8 and a plate 11 which can pivot in the direction of the double arrow 9 The upper edge 12 of the guide plate 7

  or of the plate 11 is situated far above the axis of the

  horizontal dian 13 of the front deflection drum 6; the guide plate 7 ends at a height close to that of the projection line 14 of the materials which is -9 - shown diagrammatically in FIG. 1 and which is located at the level of the front deflection drum 6 The projection line 14 of the material, which moves in the direction of the periphery of the drum depending on the composition of the materials and the speed of the conveyor belt 2, is located substantially at the place where the mixture of materials 15 transported by the belt

  conveyor 2 slides or falls under the action of the

  health in the area of the return drum 6 and moves away from the conveyor belt 2 The upper edge 12 of

  the guide plate 7 extends at a distance from the end

  head 4 or end of the endless conveyor 1 which defines an empty space 16, this distance, measured in the radial direction between the curved part of the front deflection drum 6 or of the conveyor belt 2 and

  the upper edge 12 of the plate II of the guide sheet

  dage 7 being equal to the opening width of the empty space 16; the opening width of the empty space 16 is smaller than the metal wires 17 contained in the mixture of materials 15 (see FIG. 2) and greater than the non-ferrous granular metals 18 contained in the mixture of materials 15 La t 8 the guide 7, which has at least the same width as the conveyor belt 2, can, apart from the pivoting position indicated by the arrow 9, be moved horizontally in the direction of the double arrow 19 and in height in the direction of the double arrow 21, which makes it possible to obtain different adjustment positions suitable for all

the operating conditions.

  For the separation of metal wires 17 from

  of a mixture of materials previously screened containing

  Still further, next to the metallic wires and non-ferrous metals 18, the mixture of materials 15 is loaded onto a

  vibrating gutter 23 constituting the supply conveyor.

  During its transport in the transport direction 23, - the mixture of materials 15 is homogenized in the direction of the height and in the direction of the width on the vibrating gutter 22 and, at the same time, the metal wires 17 are oriented in the lengthwise; so that the metal wires 17 maintain their orientation, the taste

  vibrating face 22 may include longitudinal grooves

  The vibrating gutter 22, which is sloping in the di-

  rection 23, overhanging from a low height, the mixture of materials 15 on the conveyor belt 2 of the endless conveyor 1 If the metal wires 17 were not yet oriented at this time, their orientation would however be ensured due to the fact that at when the metal wires 17

  fall from vibrating gutter 22 onto the conveyor belt

  carrier 2, the two ends of a piece of wire

  metal 17 do not arrive simultaneously on the conveyor belt 2 Therefore, the end of the metal wire which reaches the conveyor belt 2 is already entrained

  in the direction of transport before the other extremi-

  metal wire reaches the conveyor belt 2, so that in this way also the orientation

  wire is assured The speed of the run-

  conveyor line 2 is greater than the speed of trans-

  port of the vibrating gutter 22, so that the height of the layer of the material mixture 15 is still

  reduced due to spillage on the drive belt

  carrier 2, which gives a single layer.

  Conveyor belt 2 transports the mixture of

  materials 15 well beyond the top point (see ver-

  25) of the deflection drum 6 On reaching the material projection line 14, the material mixture 15 falls or slides and moves away from the conveyor belt 2 While the small pieces of non-ferrous metal 18 pass into space vacuum 16 between the t 8 the guide 7 and the conveyor belt 2 and fall along a parabola 26 substantially vertica I (see Figure 2), the il -

  metal wires 17, on the other hand, cross without diffi-

  cultivated the empty space 16 (see Figure 2) Indeed, because

  sound of their length, the metal wires 17 pass

  over the empty space 16 and cross the upper edge

  12 of the plate 11 of the guide sheet 7 to arrive on the side of the guide sheet 7 (or of the plate 11) which, seen in the direction of transport 23, is behind and along which they slide, as indicated by arrow 28 in FIG. 2, on the

  rear surface 27 of the plate 11.

  In any case, the guide plate 7 (or plate 11) e whose upper edge 12 is only a short distance from the outer surface of the conveyor belt 2 and which ends substantially in the region of the line of projection 14, ensures a clear separation between the metallic wires 17 and the non-ferrous metals 18 Indeed, while the metallic wires 17 cross

  without difficulty lt narrow empty space 16 separating the

  non-ferrous metals, conveyor line 2 of the upper edge 12 of the guide plate 7 and, therefore, accumulate in a metal wire collector 29 located, in the direction of transport, behind the guide sheet 7 fall substantially vertically into the empty space

  16 (see falling dish 26 in Figure 2) and ar-

  rivets in a non-ferrous metal collector 31 which is located at the bottom of the side of the guide plate 7 which,

  seen in transport direction 23, is in front.

12 -

Claims (6)

  1 Process for the separation of large components   different from a mixture of solids, especially   ges containing non-ferrous metals, characterized in that, for the separation of pieces of metal wire, pins or the like from a mixture of solids previously sieved through orifices   sieves less than 20 mm, the mixture of solids   holding pieces of metal wire oriented in the direction of transport is brought to a conveyor without   end to an empty space which, on the trans-   port, is located immediately after the endless conveyor so as to allow granular material to pass through and whose opening width is narrower than the most   small length of metal wires to separate.   2 Device for applying the method according to the resale   dication 1, characterized in that the free space (16) is located between the endless conveyor (1) and a sheet of guide (7).   3 Device according to claim 2, characterized in that the largest granular constituents of the sieved fraction pass directly between the conveyor   endless (1) and the guide plate (7).   4 Device according to one of claims 1 or 2, charac-   characterized in that the guide plate (7) ends near the projection line (14) of the conveyor endless (1).   Device according to one or more of Claims 2 to   4, characterized in that the guide plate (7) can be moved and adjusted.   6 Device according to one or more of claims 2 to   , characterized in that the guide plate (7) is in several parts. 13 -   7 Device according to one or more of claims 2 to   6, characterized in that the speed of the endless conveyor is variable.   Device according to one or more of Claims 2 to   7, characterized in that the endless conveyor (1) comprises a driven conveyor belt (2) guided, at least at its loading ends * and   evacuation (3, 4), on return drums (5, 6).