EP4200085B1 - Screen plate for a separating device for classifying bulk material - Google Patents
Screen plate for a separating device for classifying bulk material Download PDFInfo
- Publication number
- EP4200085B1 EP4200085B1 EP20761555.0A EP20761555A EP4200085B1 EP 4200085 B1 EP4200085 B1 EP 4200085B1 EP 20761555 A EP20761555 A EP 20761555A EP 4200085 B1 EP4200085 B1 EP 4200085B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- circle
- profile
- screen plate
- separating
- sieve plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000013590 bulk material Substances 0.000 title claims description 23
- 230000007704 transition Effects 0.000 claims description 5
- 238000012360 testing method Methods 0.000 description 27
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 22
- 239000000463 material Substances 0.000 description 21
- 239000002245 particle Substances 0.000 description 21
- 229920005591 polysilicon Polymers 0.000 description 19
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical group [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 12
- 239000012634 fragment Substances 0.000 description 12
- 239000010703 silicon Substances 0.000 description 10
- 229910052710 silicon Inorganic materials 0.000 description 9
- 238000000926 separation method Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 238000012216 screening Methods 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 4
- 229910003460 diamond Inorganic materials 0.000 description 3
- 239000010432 diamond Substances 0.000 description 3
- 239000008187 granular material Substances 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- -1 polypropylene Polymers 0.000 description 3
- 239000012495 reaction gas Substances 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 2
- 239000004743 Polypropylene Substances 0.000 description 2
- 229910003481 amorphous carbon Inorganic materials 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 229910021419 crystalline silicon Inorganic materials 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000004810 polytetrafluoroethylene Substances 0.000 description 2
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 2
- 239000004814 polyurethane Substances 0.000 description 2
- 229920000915 polyvinyl chloride Polymers 0.000 description 2
- 239000004800 polyvinyl chloride Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000002231 Czochralski process Methods 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 229920001774 Perfluoroether Polymers 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- UQZIWOQVLUASCR-UHFFFAOYSA-N alumane;titanium Chemical compound [AlH3].[Ti] UQZIWOQVLUASCR-UHFFFAOYSA-N 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
- B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
- B07B1/00—Sieving, screening, sifting, or sorting solid materials using networks, gratings, grids, or the like
- B07B1/46—Constructional details of screens in general; Cleaning or heating of screens
- B07B1/4609—Constructional details of screens in general; Cleaning or heating of screens constructional details of screening surfaces or meshes
- B07B1/4654—Corrugated Screening surfaces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
- B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
- B07B13/00—Grading or sorting solid materials by dry methods, not otherwise provided for; Sorting articles otherwise than by indirectly controlled devices
- B07B13/04—Grading or sorting solid materials by dry methods, not otherwise provided for; Sorting articles otherwise than by indirectly controlled devices according to size
- B07B13/07—Apparatus in which aggregates or articles are moved along or past openings which increase in size in the direction of movement
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
- B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
- B07B1/00—Sieving, screening, sifting, or sorting solid materials using networks, gratings, grids, or the like
- B07B1/12—Apparatus having only parallel elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
- B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
- B07B13/00—Grading or sorting solid materials by dry methods, not otherwise provided for; Sorting articles otherwise than by indirectly controlled devices
- B07B13/04—Grading or sorting solid materials by dry methods, not otherwise provided for; Sorting articles otherwise than by indirectly controlled devices according to size
Definitions
- the subject of the invention is a sieve plate for a separating device for mechanically classifying bulk material, in particular polycrystalline silicon fragments.
- Polycrystalline silicon (polysilicon) is commonly produced using the Siemens process - a chemical vapor deposition process.
- Thin filament rods (thin rods) made of silicon are heated in a bell-shaped reactor (Siemens reactor) by direct current passage, and a reaction gas containing a silicon-containing component (e.g. monosilane or halosilane) and hydrogen is introduced.
- the surface temperature of the filament rods is usually more than 1000°C. At these temperatures, the silicon-containing component of the reaction gas decomposes, and elemental silicon separates from the gas phase as polysilicon on the rod surface, increasing the rod diameter. After a predetermined diameter is reached, the deposition is stopped and the silicon rods obtained are removed.
- Polysilicon is the starting material in the production of single-crystalline silicon, which is produced, for example, using the Czochralski process (crucible drawing). Furthermore, polysilicon is required for the production of multicrystalline silicon, for example using ingot casting processes. For both processes, the polysilicon rods must be crushed into fragments. These are usually classified according to size in separators. The separating devices are usually screening machines that mechanically sort or classify the polysilicon fragments into different size classes.
- Polysilicon can also be produced in the form of granules in a fluidized bed reactor. This is done by fluidizing silicon seed particles using a gas flow in a fluidized bed, which is heated using a heating device. By adding a silicon-containing reaction gas, a deposition reaction occurs on the hot particle surface, whereby elemental silicon is deposited on the seed particles with an increase in diameter.
- the polysilicon granulate is also usually divided into two or more fractions using a screening system (classification).
- the smallest fraction (undersized sieve) can then be processed into germ particles in a grinding plant and fed to the reactor.
- the target fraction product grain is usually packaged and transported to the customer.
- Sieving machines are generally used to separate solids according to grain sizes. Depending on the movement characteristics, a distinction can be made between vibrating screen machines and vibrating screen machines.
- the screening machines are usually driven electromagnetically or by unbalanced motors or gears.
- the movement of the sieve lining serves to further transport the feed material in the longitudinal direction of the sieve and to allow the sieve undersize to pass through the sieve openings.
- vibrating screen machines have both horizontal and vertical screen acceleration.
- Multi-deck screening machines can fractionate several grain sizes at the same time.
- the drive principle in multi-deck flat screen machines is based on two counter-rotating unbalance motors that generate a linear vibration, with the broken material moving in a straight line over a horizontal separating surface.
- a large number of screen decks can be put together to form a screen stack. This means that different Grain sizes can be produced in a single machine without the need to change screen decks.
- WO 2016/202473 A1 describes a profiled sieve plate with a V-profile, which has enlarging openings on one removal side.
- the tapered depressions and elevations can cause jamming of product grain (jammed bulk material can also be referred to as stuck grain) in the product flow and in the opening area.
- stuck grain jamming of product grain
- This can lead to a deterioration in the classifying quality, as the undersize fraction to be separated passes through the plug grain into the target grain. To prevent this, the plug grain must also be removed regularly, which results in longer service life.
- WO 2018/108334 A1 represents an improvement in WO 2016/202473 A1 described sieve plate.
- the openings on the removal side had an additional widening.
- the sieve plate has rather poor separation of coarse grain/target grain and fine grain (selectivity). Due to the sieve geometry, large particles can push the undersize ahead of them and prevent the undersize from being separated.
- EP1079939 A1 discloses a sieve plate for a separating device according to the preamble of claims 1 and 5.
- this rounded profile enables the undersize fraction (fines to be separated) to separate even better from the product grain.
- the profiled area causes larger amounts of undersized particles to collect in the rounded depressions. Larger fragments are transported away on the sieve plate above the undersize fraction in the depressions, usually without coming into contact with the undersize fraction. This leads to a high separation quality.
- the profile prevents larger fragments from getting stuck in the recesses due to jamming.
- the widened opening edge on the one hand, prevents large fragments from jamming, and on the other hand, it ensures unhindered separation of the undersize fraction if a larger fragment gets jammed.
- the sieve plate according to the invention is a further development of the one in WO 2018/108334 A1 described sieve plate.
- the circles K1 and K2 may touch at a point T0, or they may be connected to each other by a common tangent, the tangent touching the circle K1 at a point T1 and the circle K2 at a point T2. Accordingly, the tangent describes the profile with the circular arcs if necessary.
- the circles K1 and K2 are preferably arranged next to one another with the proviso that the depressions of the profile always widen upwards (cf. Fig. 2B ).
- the circular arc of the circle K1 describing the elevations of the profile extends from the apex of the elevation to point T0 or T1.
- the circular arc of the circle K2 describing the depressions of the profile extends from the apex of the depression to the point T0 or T2.
- the two circles K1 and K2 can also be connected to one another via the points T1 and T2 by a higher-order function, a hyperbola or an elliptical arc; However, taking into account the proviso that the depressions in the profile always widen upwards.
- the bulk material can be broken polysilicon material, for example crushed polysilicon rods from the Siemens process.
- the bulk material can also be polysilicon granules.
- the bulk material is placed in a feed area, which lies opposite the removal area, is placed on the sieve plate.
- the opening edge is preferably concave, i.e. curved into the interior of the sieve plate or in the direction of the feed area, and has a depth t, where t is 0 ⁇ t ⁇ 5*r2, preferably r2 to 5*r2, particularly preferably r2 to 4 *r2, especially 2*r2 to 3*r2. (see. Fig. 4A ).
- the opening edge is rectangular and has a depth t, where t is 0 ⁇ t ⁇ 5*r2, preferably r2 to 5*r2, particularly preferably r2 to 4*r2, in particular 2*r2 to 3*r2 . (see. Fig. 4B ).
- the profile of the sieve plate can preferably have the two configurations described below.
- Small-sized bulk material should be understood to mean a subset of the quantity of bulk material fed in, which is to be separated using the sieve plate. The small-sized bulk material therefore corresponds to the fraction to be separated.
- ⁇ is an angle that defines the position from M2 to M1 in a Cartesian coordinate system when M1 and M2 are vertices of a right-angled triangle and e corresponds to the hypotenuse of the triangle (cf. Fig. 5 ).
- r2 ⁇ r1 applies to the sieve plate, where 0 ⁇ r2 / r1 ⁇ 1, preferably 0.2 ⁇ r2 / r1 ⁇ 0.4. Furthermore, r1 + r2 > e, where e corresponds to the distance between the center of the circle M1 from K1 and M2 from K2, and the circles K1 and K2 do not touch each other.
- ⁇ is an angle that defines the position from M2 to M1 in a Cartesian coordinate system , if M1 and M2 are vertices of a right-angled triangle and e corresponds to the hypotenuse of the triangle, where the circular arcs (or the circles K1 and K2) are connected to one another by a common tangent through the points T1 of K1 and T2 of K2 (cf. Fig. 6 ).
- the profile of the sieve plate can preferably have the two configurations described below.
- Large-scale bulk material should be understood to mean a subset of the quantity of bulk material fed in, which is to be separated using the sieve plate. The large bulk material therefore corresponds to the fraction to be separated. Oversize particles can clog individual recesses or damage the sieve plate.
- the profile of the sieve plate for removing oversized particles is r2 > r1, where 0 ⁇ r1/r2 ⁇ 1, preferably 0.2 ⁇ r1/r2 ⁇ 0.4.
- r1 + r2 e, where e corresponds to the distance between the circle center M1 of K1 and the circle center M2 of K2, and K1 and K2 touch each other at a point T0 in which the circular arcs merge into one another.
- r2 > r1 applies to the sieve plate, where 0 ⁇ r1/r2 ⁇ 1, preferably 0.2 ⁇ r1/r2 ⁇ 0.4.
- r1 + r2 > e where e corresponds to the distance between the circle center M1 of K1 and the circle center M2 of K2, and the circles K1 and K2 do not touch each other.
- e corresponds to the distance between the circle center M1 of K1 and the circle center M2 of K2, and the circles K1 and K2 do not touch each other.
- the sieve plate is made of a material selected from the group consisting of plastic, ceramic, glass, diamond, amorphous carbon, silicon, metal and combinations thereof.
- the sieve plate or at least the part of the sieve plate that comes into contact with the bulk material can be lined or coated with a material selected from the group consisting of plastic, ceramic, glass, diamond, amorphous carbon, silicon and combinations thereof.
- the sieve plate can have a coating made of titanium nitride, titanium carbide, silicon nitride, silicon carbide, aluminum titanium nitride or DLC (Diamond Like Carbon).
- the plastic can be, for example, PVC (polyvinyl chloride), PP (polypropylene), PE (polyethylene), PU (polyurethane), PFA (perfluoroalkoxy polymer), PVDF (polyvinylidene fluoride) and PTFE (polytetrafluoroethylene).
- PVC polyvinyl chloride
- PP polypropylene
- PE polyethylene
- PU polyurethane
- PFA perfluoroalkoxy polymer
- PVDF polyvinylidene fluoride
- PTFE polytetrafluoroethylene
- the sieve plate preferably consists of a hard metal.
- a further aspect of the invention relates to a separating device for classifying bulk material, comprising at least one of the sieve plates described and at least one separating element with a separating edge arranged below the removal area of the sieve plate.
- the length of the separating element preferably corresponds to the length of the removal side of the sieve plate.
- the distance of the separating element from the removal area is preferably variable.
- the separating element is used to separate undersized or oversized particles from the target fraction.
- the separating element is static and does not vibrate with the sieve plate.
- the separating element preferably has a triangular side profile, in particular the side profile of an acute-angled triangle.
- the separating edge of the separating element preferably has the same profile as the sieve plate.
- the separating edge can also be designed to be straight, so that the separating element has the contour of a rectangle in front view.
- FIG. 1A a section of a sieve plate 10 according to the invention with a profile area 11 and a removal area 12 is shown.
- the profile area 11 has alternating elevations 14 and depressions 16.
- the depressions 16 merge into openings 18 in the removal area 12, through which the bulk material can fall depending on its size.
- the transition between recess 16 and opening 18 is formed by an opening edge 17, which is based on the 3 and 4 is described in more detail.
- the openings 18 widen towards a removal side 19 (dashed line).
- the profiling is basically maintained in the removal area 12, with the openings 18 preferably being punched or milled into a profile area.
- the projections 15 formed in this way are correspondingly curved and form a continuation of the elevations 14.
- the removal area 12 basically lies between the opening edges 17 and the removal side 19. If necessary, it may be preferred that the opening edges 17 are not at the same height.
- the Figure 1B shows a front view of the sieve plate 10.
- the removal area 12 cannot be distinguished from the profile area 11 from this perspective.
- the sieve plate is arranged in a holder 13, the holder 13 extending maximally up to the opening edges 17.
- the Figure 2A shows how the profile of the sieve plate 10 (cf. Fig 1 ) can be written with the help of two circles K1 and K2 arranged next to each other, which touch each other at a point T0.
- the elevations 14 are described by a circular arc of the circle K1 shown in bold with the radius r1.
- the Depressions 16 are described with a circular arc of the circle K2 shown in bold with the radius r2, the circular arcs merging into one another at the contact point T0.
- K1 and K2 are arranged next to one another in such a way that the depressions 16 always widen.
- This expansion is in Fig 2B shown as an example. It should preferably apply to the depressions 16 that l 0 ⁇ l n ⁇ l 1+n .
- the Figure 3 shows a detailed view of the opening edge 17 in a top view.
- the opening edge 17 has a width that corresponds to twice the radius r2 of the circle K2 (cf. Fig. 2 ). Also shown is the radius r1 of the circle K1.
- FIG. 4 shows two configurations of the sieve plate 10, where Fig. 4A an embodiment with a concave opening edge 17 and Fig. 4B represents an embodiment with a rectangular opening edge 17.
- the Figure 5 illustrates a profile of the sieve plate 10, which is particularly suitable for separating small-sized bulk material (undersized particles).
- the position of the circles K1 and K2 relative to each other, which touch each other at a point T0, can be described by a right-angled triangle, where the hypotenuse is the connecting line e between the circle centers M1 and M2 and where the adjacent a is parallel to the x-axis of a Cartesian Coordinate system runs.
- the angle ⁇ (to the countercathete) significantly determines the profile course of the sieve plate 10.
- ⁇ is approximately 30°, which results in the profile course indicated in the form of the bold line .
- the Figure 6 shows the profile of a sieve plate 10, which is also particularly suitable for separating undersized particles.
- K1 and K2 do not touch each other, but are connected via a common tangent through the points T1 and T2.
- the angle ⁇ here is approx. 25°.
- FIGS. 7 and 8 each show a profile of a sieve plate 10, which is particularly suitable for separating oversize particles.
- the main difference compared to the separation of undersized particles is that the circle K1 has a smaller radius r1 than the circle K2.
- the Figure 9A shows a separating device 100 with a sieve plate 10 and a separating element 30, which is arranged below the removal area 12 and is intended to separate the target fraction from oversize or undersize particles.
- the separating element 30 has a profiled separating edge 32, the profiling being in the Figure 9B can be recognized.
- the profiling of the separating edge 32 preferably corresponds to the profiling of the sieve plate 10.
- the separating element can be pivoted through an angle ⁇ .
- On the side of the sieve plate 10 opposite the removal area 12 is a feed area 20, which directly adjoins the profile area, but does not necessarily have to have a profiling. If necessary, the bulk material is brought to the feed area using a conveyor belt (not shown).
- the Figure 10 shows a further embodiment of a separating device 100, which has two sieve plates 10A, 10B arranged one after the other.
- the first separating element 30A is located after the first sieve plate 10A.
- the separating element 30A can be pivoted through an angle ⁇ .
- the sieve undersize is separated and collected in the collecting container 40A.
- the undersize separation is supported by a blower 50, which can change its direction of action by an angle ⁇ .
- the product grain is further conveyed to the second sieve plate 10B, and there the oversize is separated from the product grain by means of a second separating element 30B.
- the product grain is collected in the collecting container 40B, the oversize in the collecting container 40C.
- the angle ⁇ of the separating element 30A can be 80°.
- the angle ⁇ of the fan 50A can be 30°.
- the angle ⁇ of the separating element 30A can be 90°.
- the Figures 11 and 12 each show a further embodiment of the separating device 100.
- Two separating elements 30 are arranged directly after a sieve plate 10. This makes it possible to use a sieve plate 10 to separate the oversize fractions (collection container 40C) and fines (collection container 40A) in just one step.
- the Figure 12 shows a similar variant as Figure 10 . In Figure 12 However, the arrangement is reversed and first the oversize (collection container 40C) and then the fine fraction (collection container 40A) are separated using a second sieve plate 10A.
- Figures 10 to 12 can be expanded or changed as desired.
- the polysilicon material delivered in a bag by a polysilicon manufacturer may also contain smaller fragments and an undersize fraction (undersize).
- undergrain especially with grain sizes smaller than 4 mm, has a negative influence on the drawing process in the production of single-crystalline silicon and for this reason must be removed before use.
- Polysilicon with fracture size 2 (BG 2) was used for the test.
- the size class of polysilicon fragments is defined as the longest distance between two points on the surface of a silicon fragment (equivalent to the maximum length): BG 0 0.1 to 5mm BG 1 3 to 15mm BG2 10 to 40mm BG 3 20 to 60mm BG 4 45 to 120mm BG 5 100 to 250mm
- the separated undersize fraction (undersize) was collected and weighed.
- test material 10 kg (without undersize fraction ⁇ 4 mm) were placed on a conveyor unit.
- the test material is preferably added via a funnel.
- the container to be filled is positioned at the end of the screening section above the first conveyor unit so that the test material can be conveyed into the container without any problems.
- the undersize fraction separated in advance is used for this test.
- 2 g of undersize fraction are added to every 2 kg of test material, so that a total of approx. 10 g of undersize fraction was added.
- the delivery rate was set to 3 kg ⁇ 0.5 kg per minute before the test run.
- the removed undersize fraction was collected and weighed.
- the experiments were carried out five times per setting.
- the separating edge of the separating element had no profile.
- the separating edge of the separating element had no profile.
- the separating edge of the separating element had no profile.
- the separating edge of the separating element had the same profiling as the sieve plate.
- the separating edge is arranged in relation to the profile of the sieve plate in such a way that the elevations of the separating edge point towards the recesses of the sieve plate.
- Table 1 shows the mean results compared to the results from the WO 2018/108334 A1 .
- Table 1 test Test material [kg] Addition of undersize [g] Removed undersize [g] Removal rate [%] WO2018/108334 (1) 10 10 8.3 83 1 10 10 9.5 95 2 10 10 9.0 90 3 10 10 9.2 92 4 10 10 9, 6 96
- the polysilicon material delivered in the bag by the polysilicon manufacturer must not contain any excessively large fragments (oversize particles).
- the oversize can cause blockages and damage and must therefore be removed before use.
- the BG 2 was used for the test.
- the container to be filled is positioned at the end of the screening section above the first conveyor unit so that the test material can be conveyed into the container.
- the delivery rate was set to 15 kg ⁇ 1 kg per minute before the test run.
- the removed oversize was collected and weighed.
- the experiments were carried out five times per setting.
- Table 2 shows the average results for oversize separation: Table 2 test Test material [kg] Addition of oversize [g] Removed oversize [g] Removal rate [%] 1 10 500 380 76 2 10 500 440 88 3 10 500 500 100 4 10 500 300 60
Landscapes
- Combined Means For Separation Of Solids (AREA)
- Silicon Compounds (AREA)
- Crushing And Grinding (AREA)
Description
Gegenstand der Erfindung ist eine Siebplatte für eine Trennvorrichtung zum mechanischen Klassieren von Schüttgut, insbesondere von polykristallinem Siliciumbruch.The subject of the invention is a sieve plate for a separating device for mechanically classifying bulk material, in particular polycrystalline silicon fragments.
Polykristallines Silicium (Polysilicium) wird üblicherweise durch das Siemens-Verfahren - ein chemischer Gasphasenabscheidungsprozess - hergestellt. Dabei werden in einem glockenförmigen Reaktor (Siemens-Reaktor) dünne Filamentstäbe (Dünnstäbe) aus Silicium durch direkten Stromdurchgang erhitzt, und ein Reaktionsgas enthaltend eine siliciumhaltige Komponente (z.B. Monosilan oder Halogensilan) und Wasserstoff wird eingeleitet. Die Oberflächentemperatur der Filamentstäbe beträgt üblicherweise mehr als 1000°C. Bei diesen Temperaturen zersetzt sich die siliciumhaltige Komponente des Reaktionsgases, und elementares Silicium scheidet sich aus der Gasphase als Polysilicium auf der Staboberfläche unter Zunahme des Stabdurchmessers ab. Nachdem ein vorgegebener Durchmesser erreicht ist, wird die Abscheidung gestoppt und die erhaltenen Siliciumstäbe werden ausgebaut.Polycrystalline silicon (polysilicon) is commonly produced using the Siemens process - a chemical vapor deposition process. Thin filament rods (thin rods) made of silicon are heated in a bell-shaped reactor (Siemens reactor) by direct current passage, and a reaction gas containing a silicon-containing component (e.g. monosilane or halosilane) and hydrogen is introduced. The surface temperature of the filament rods is usually more than 1000°C. At these temperatures, the silicon-containing component of the reaction gas decomposes, and elemental silicon separates from the gas phase as polysilicon on the rod surface, increasing the rod diameter. After a predetermined diameter is reached, the deposition is stopped and the silicon rods obtained are removed.
Polysilicium ist das Ausgangsmaterial bei der Produktion von einkristallinem Silicium, das beispielsweise mittels des Czochralski-Verfahrens (Tiegelziehen) hergestellt wird. Ferner wird Polysilicium zur Herstellung von multikristallinem Silicium, beispielsweise mittels Blockgussverfahren, benötigt. Für beide Verfahren müssen die Polysiliciumstäbe zu Bruchstücken zerkleinert werden. Diese werden üblicherweise in Trennvorrichtungen nach Größen klassiert. Bei den Trennvorrichtungen handelt es sich in der Regel um Siebmaschinen, die den Polysiliciumbruch mechanisch in unterschiedliche Größenklassen sortieren bzw. klassieren.Polysilicon is the starting material in the production of single-crystalline silicon, which is produced, for example, using the Czochralski process (crucible drawing). Furthermore, polysilicon is required for the production of multicrystalline silicon, for example using ingot casting processes. For both processes, the polysilicon rods must be crushed into fragments. These are usually classified according to size in separators. The separating devices are usually screening machines that mechanically sort or classify the polysilicon fragments into different size classes.
Polysilicium kann ferner in Form von Granulat in einem Wirbelschichtreaktor produziert werden. Dies geschieht durch Fluidisierung von Silicium-Keimpartikeln mittels einer Gasströmung in einer Wirbelschicht, wobei diese über eine Heizvorrichtung aufgeheizt wird. Durch Zugabe eines siliciumhaltigen Reaktionsgases kommt es zu einer Abscheidereaktion an der heißen Partikeloberfläche, wobei sich elementares Silicium auf den Keimpartikeln unter Zunahme des Durchmessers abscheidet.Polysilicon can also be produced in the form of granules in a fluidized bed reactor. This is done by fluidizing silicon seed particles using a gas flow in a fluidized bed, which is heated using a heating device. By adding a silicon-containing reaction gas, a deposition reaction occurs on the hot particle surface, whereby elemental silicon is deposited on the seed particles with an increase in diameter.
Auch das Polysiliciumgranulat wird üblicherweise mittels einer Siebanlage in zwei oder mehr Fraktionen geteilt (Klassierung). Die kleinste Fraktion (Siebunterkorn) kann anschließend in einer Mahlanlage zu Keimpartikeln verarbeitet und dem Reaktor zugeführt werden. Die Zielfraktion (Produktkorn) wird üblicherweise verpackt und zum Kunden transportiert.The polysilicon granulate is also usually divided into two or more fractions using a screening system (classification). The smallest fraction (undersized sieve) can then be processed into germ particles in a grinding plant and fed to the reactor. The target fraction (product grain) is usually packaged and transported to the customer.
Siebmaschinen dienen generell der Trennung von Feststoffen nach Korngrößen. Nach Bewegungscharakteristik kann zwischen Planschwingsiebmaschinen und Wurfsiebmaschinen unterschieden werden. Der Antrieb der Siebmaschinen erfolgt meist elektromagnetisch bzw. durch Unwuchtmotoren oder -getriebe. Die Bewegung des Siebbelags dient dem Weitertransport des Aufgabeguts in Sieblängsrichtung und dem Durchtritt des Siebunterkorns durch die Sieböffnungen. Im Gegensatz zu Planschwingsiebmaschinen tritt bei Wurfsiebmaschinen neben der horizontalen auch eine vertikale Siebbeschleunigung auf.Sieving machines are generally used to separate solids according to grain sizes. Depending on the movement characteristics, a distinction can be made between vibrating screen machines and vibrating screen machines. The screening machines are usually driven electromagnetically or by unbalanced motors or gears. The movement of the sieve lining serves to further transport the feed material in the longitudinal direction of the sieve and to allow the sieve undersize to pass through the sieve openings. In contrast to vibrating screen machines, vibrating screen machines have both horizontal and vertical screen acceleration.
Mehrdecksiebmaschinen können gleichzeitig mehrere Korngrößen fraktionieren. Das Antriebsprinzip bei Mehrdeck-Plansiebmaschinen beruht auf zwei gegenläufig arbeitenden Unwuchtmotoren, die eine lineare Schwingung erzeugen, wobei sich das Bruchgut geradlinig über eine horizontale Trennfläche bewegt. Durch ein Baukastensystem können eine Vielzahl von Siebdecks zu einem Siebstapel zusammengestellt werden. Somit können unterschiedliche Körnungen in einer einzigen Maschine hergestellt werden, ohne dass Siebdecks gewechselt werden müssen.Multi-deck screening machines can fractionate several grain sizes at the same time. The drive principle in multi-deck flat screen machines is based on two counter-rotating unbalance motors that generate a linear vibration, with the broken material moving in a straight line over a horizontal separating surface. Using a modular system, a large number of screen decks can be put together to form a screen stack. This means that different Grain sizes can be produced in a single machine without the need to change screen decks.
Üblicherweise findet die Klassierung entweder über Lochsiebe, Stangensiebe oder profilierte Siebplatten mit Erhebungen und Tälern und gegebenenfalls V-förmigen Öffnungen an einer Seite statt.Classification usually takes place either using perforated screens, bar screens or profiled screen plates with elevations and valleys and, if necessary, V-shaped openings on one side.
Bei der Klassierung über Lochsiebe, wie sie beispielsweise in der
Aus dieser Problematik ergab sich die Aufgabenstellung der Erfindung.The task of the invention arose from this problem.
Die Aufgabe wird gelöst durch Ansprüche 1 und 5.The task is solved by
Es hat sich gezeigt, dass dieses abgerundete Profil der Unterkornfraktion (abzutrennender Feinanteil) noch besser ermöglicht, sich vom Produktkorn zu separieren. Der profilierte Bereich führt dazu, dass sich größere Mengen der Unterkornfraktion in den gerundeten Vertiefungen sammeln. Größere Bruchstücke werden auf der Siebplatte über der Unterkornfraktion in den Vertiefungen hinwegtransportiert, in der Regel, ohne mit der Unterkornfraktion in Berührung zu kommen. Dies führt zu einer hohen Abtrenngüte. Das Profil verhindert, dass größere Bruchstücke in den Vertiefungen durch Verklemmen stecken bleiben. Insbesondere auch die verbreiterte Öffnungskante verhindert zum einen ein Verklemmen großer Bruchstücke, zum anderen gewährleistet sie ein ungehindertes Abtrennen der Unterkornfraktion, falls es zum Verklemmen eines größeren Bruchstücks kommt.It has been shown that this rounded profile enables the undersize fraction (fines to be separated) to separate even better from the product grain. The profiled area causes larger amounts of undersized particles to collect in the rounded depressions. Larger fragments are transported away on the sieve plate above the undersize fraction in the depressions, usually without coming into contact with the undersize fraction. This leads to a high separation quality. The profile prevents larger fragments from getting stuck in the recesses due to jamming. In particular, the widened opening edge, on the one hand, prevents large fragments from jamming, and on the other hand, it ensures unhindered separation of the undersize fraction if a larger fragment gets jammed.
Insbesondere handelt es sich bei der erfindungsgemäßen Siebplatte um eine Weiterentwicklung der in
Die Kreise K1 und K2 können sich in einem Punkt T0 berühren, oder sie sind durch eine gemeinsame Tangente miteinander verbunden, wobei die Tangente den Kreis K1 in einem Punkt T1 und den Kreis K2 in einem Punkt T2 berührt. Entsprechend beschreibt die Tangente gegebenenfalls mit den Kreisbögen das Profil. Vorzugsweise sind die Kreise K1 und K2 mit der Maßgabe nebeneinander angeordnet, dass sich die Vertiefungen des Profils stets nach oben hin aufweiten (vgl.
Grundsätzlich können die beiden Kreise K1 und K2 über die Punkte T1 und T2 auch durch eine Funktion höherer Ordnung, eine Hyperbel oder einen Ellipsenbogen miteinander verbunden sein; allerdings unter Beachtung der Maßgabe, dass sich die Vertiefungen des Profils stets nach oben hin aufweiten.In principle, the two circles K1 and K2 can also be connected to one another via the points T1 and T2 by a higher-order function, a hyperbola or an elliptical arc; However, taking into account the proviso that the depressions in the profile always widen upwards.
Bei dem Schüttgut kann es sich um Polysiliciumbruchgut, z.B. zerkleinerte Polysiliciumstäbe aus dem Siemens-Verfahren, handeln. Bei dem Schüttgut kann es sich auch um Polysiliciumgranulat handeln. Generell wird das Schüttgut in einem Aufgabebereich, welcher dem Entnahmebereich gegenüberliegt, auf die Siebplatte verbracht.The bulk material can be broken polysilicon material, for example crushed polysilicon rods from the Siemens process. The bulk material can also be polysilicon granules. In general, the bulk material is placed in a feed area, which lies opposite the removal area, is placed on the sieve plate.
Die Öffnungskante verläuft vorzugsweise konkav, also ins Innere der Siebplatte bzw. in Richtung des Aufgabebereichs gewölbt, und weist eine Tiefe t auf, wobei für t gilt 0 < t ≤ 5*r2, bevorzugt r2 bis 5*r2, besonders bevorzugt r2 bis 4*r2, insbesondere 2*r2 bis 3*r2. (vgl.
Gemäß einer weiteren Ausführungsform verläuft die Öffnungskante rechteckig und weist eine Tiefe t auf, wobei für t gilt 0 < t ≤ 5*r2, bevorzugt r2 bis 5*r2, besonders bevorzugt r2 bis 4*r2, insbesondere 2*r2 bis 3*r2. (vgl.
Für eine Entfernung von kleinteiligem Schüttgut (auch als Unterkorn bezeichnet) kann das Profil der Siebplatte vorzugsweise die beiden nachfolgend beschriebenen Konfigurationen aufweisen. Unter kleinteiligem Schüttgut soll dabei eine Teilmenge aus der aufgegebenen Menge an Schüttgut verstanden werden, die mittels der Siebplatte abgetrennt werden soll. Das kleinteilige Schüttgut entspricht also der abzutrennenden Fraktion.For the removal of small-sized bulk material (also referred to as undersized particles), the profile of the sieve plate can preferably have the two configurations described below. Small-sized bulk material should be understood to mean a subset of the quantity of bulk material fed in, which is to be separated using the sieve plate. The small-sized bulk material therefore corresponds to the fraction to be separated.
Erfindungsgemäß gilt für das Profil der Siebplatte zur Entfernung von Unterkorn r2 < r1, wobei 0 < r2/r1 < 1, bevorzugt 0,2 < r2/r1 < 0,4. Ferner gilt r1 + r2 = e, wobei e dem Abstand zwischen dem Kreismittelpunkt M1 von K1 und dem Kreismittelpunkt M2 von K2 entspricht, und wobei sich die Kreise K1 und K2 in einem Punkt T0 berühren, in welchem die das Profil beschreibenden Kreisbögen ineinander übergehen.According to the invention, the profile of the sieve plate for removing undersize is r2 <r1, where 0 <r2/r1 <1, preferably 0.2 <r2/r1 <0.4. Furthermore, r1 + r2 = e, where e corresponds to the distance between the circle center M1 of K1 and the circle center M2 of K2, and where the circles K1 and K2 touch each other at a point T0, in which the circular arcs describing the profile merge into one another.
Ferner gilt 0° < α < 65°, bevorzugt 0° < α < 25°, besonders bevorzugt 5° < α < 20°, wobei α ein Winkel ist, der die Position von M2 zu M1 in einem kartesischen Koordinatensystem definiert, wenn M1 und M2 Eckpunkte eines rechtwinkligen Dreiecks sind und e der Hypotenuse des Dreiecks entspricht (vgl.
Gemäß einer weiteren Ausführung zur Entfernung von Unterkorn gilt für die Siebplatte r2 < r1, wobei 0 < r2/r1 < 1, bevorzugt 0,2 < r2/r1 < 0,4. Ferner gilt r1 + r2 > e, wobei e dem Abstand des Kreismittelpunkts M1 von K1 und M2 von K2 entspricht, und sich die Kreise K1 und K2 nicht berühren.According to a further embodiment for removing undersize, r2 < r1 applies to the sieve plate, where 0 < r2 / r1 < 1, preferably 0.2 < r2 / r1 < 0.4. Furthermore, r1 + r2 > e, where e corresponds to the distance between the center of the circle M1 from K1 and M2 from K2, and the circles K1 and K2 do not touch each other.
Ferner gilt -65° < α < 65°, bevorzugt -25° < α < 10°, besonders bevorzugt -10° < α < 5°, wobei α ein Winkel ist, der die Position von M2 zu M1 in einem kartesischen Koordinatensystem definiert, wenn M1 und M2 Eckpunkte eines rechtwinkligen Dreiecks sind und e der Hypotenuse des Dreiecks entspricht, wobei die Kreisbögen (bzw. die Kreise K1 und K2) durch eine gemeinsame Tangente durch die Punkte T1 von K1 und T2 von K2 miteinander verbunden sind (vgl.
Für eine Entfernung von großteiligem Schüttgut (auch als Überkorn bezeichnet) kann das Profil der Siebplatte vorzugsweise die beiden nachfolgend beschriebenen Konfigurationen aufweisen. Unter großteiligem Schüttgut soll dabei eine Teilmenge aus der aufgegebenen Menge an Schüttgut verstanden werden, die mittels der Siebplatte abgetrennt werden soll. Das großteilige Schüttgut entspricht also der abzutrennenden Fraktion. Überkorn kann zum Verstopfen einzelner Vertiefungen oder zu Beschädigungen der Siebplatte führen.For the removal of large bulk material (also referred to as oversize), the profile of the sieve plate can preferably have the two configurations described below. Large-scale bulk material should be understood to mean a subset of the quantity of bulk material fed in, which is to be separated using the sieve plate. The large bulk material therefore corresponds to the fraction to be separated. Oversize particles can clog individual recesses or damage the sieve plate.
Erfindungsgemäß gilt für das Profil der Siebplatte zur Entfernung von Überkorn r2 > r1, wobei 0 < r1/r2 < 1, bevorzugt 0,2 < r1/r2 < 0,4.According to the invention, the profile of the sieve plate for removing oversized particles is r2 > r1, where 0 < r1/r2 < 1, preferably 0.2 < r1/r2 < 0.4.
Ferner gilt r1 + r2 = e, wobei e dem Abstand zwischen dem Kreismittelpunkt M1 von K1 und dem Kreismittelpunkt M2 von K2 entspricht, und sich K1 und K2 in einem Punkt T0 berühren, in welchem die Kreisbögen ineinander übergehen. Des Weiteren gilt -65° < α < 0°, bevorzugt -20° < α < 0°, wobei α ein Winkel ist, der die Position von M2 zu M1 in einem kartesischen Koordinatensystem definiert, wenn M1 und M2 Eckpunkte eines rechtwinkligen Dreiecks sind und e der Hypotenuse des Dreiecks entspricht (vgl.
Gemäß einer weiteren Ausführung zur Entfernung von Überkorn gilt für die Siebplatte r2 > r1, wobei 0 < r1/r2 < 1, bevorzugt 0,2 < r1/r2 < 0,4.According to a further embodiment for removing oversized particles, r2 > r1 applies to the sieve plate, where 0 < r1/r2 < 1, preferably 0.2 < r1/r2 < 0.4.
Ferner gilt r1 + r2 > e, wobei e dem Abstand zwischen dem Kreismittelpunkt M1 von K1 und dem Kreismittelpunkt M2 von K2 entspricht, und sich die Kreise K1 und K2 nicht berühren. Des Weiteren gilt -65° < α < 65°, bevorzugt -20° < α < 0°, wobei α ein Winkel ist, der die Position von M2 zu M1 in einem kartesischen Koordinatensystem definiert, wenn M1 und M2 Eckpunkte eines rechtwinkligen Dreiecks sind und e der Hypotenuse des Dreiecks entspricht, wobei die Kreisbögen durch eine gemeinsame Tangente durch die Punkte T1 von K1 und T2 von K2 miteinander verbunden sind (vgl.
Vorzugsweise ist die Siebplatte aus einem Material ausgewählt aus der Gruppe mit Kunststoff, Keramik, Glas, Diamant, amorphem Kohlenstoff, Silicium, Metall und Kombinationen daraus.Preferably, the sieve plate is made of a material selected from the group consisting of plastic, ceramic, glass, diamond, amorphous carbon, silicon, metal and combinations thereof.
Die Siebplatte oder zumindest der mit dem Schüttgut in Berührung kommende Teil der Siebplatte kann mit einem Material ausgekleidet oder beschichtet sein, das ausgewählt ist aus der Gruppe mit Kunststoff, Keramik, Glas, Diamant, amorphem Kohlenstoff, Silicium und Kombinationen daraus.The sieve plate or at least the part of the sieve plate that comes into contact with the bulk material can be lined or coated with a material selected from the group consisting of plastic, ceramic, glass, diamond, amorphous carbon, silicon and combinations thereof.
Insbesondere kann die Siebplatte eine Beschichtung aus Titannitrid, Titancarbid, Siliciumnitrid, Siliciumcarbid, Aluminiumtitannitrid oder DLC (Diamond Like Carbon) aufweisen.In particular, the sieve plate can have a coating made of titanium nitride, titanium carbide, silicon nitride, silicon carbide, aluminum titanium nitride or DLC (Diamond Like Carbon).
Bei dem Kunststoff kann es sich z.B. um PVC (Polyvinylchlorid), PP (Polypropylen), PE (Polyethylen), PU (Polyurethan), PFA (Perfluoralkoxy-Polymer), PVDF (Polyvinylidenfluorid) und PTFE (Polytetrafluorethylen) handeln.The plastic can be, for example, PVC (polyvinyl chloride), PP (polypropylene), PE (polyethylene), PU (polyurethane), PFA (perfluoroalkoxy polymer), PVDF (polyvinylidene fluoride) and PTFE (polytetrafluoroethylene).
Vorzugsweise besteht die Siebplatte aus einem Hartmetall.The sieve plate preferably consists of a hard metal.
Ein weiterer Aspekt der Erfindung betrifft eine Trennvorrichtung zum Klassieren von Schüttgut, umfassend zumindest eine der beschriebenen Siebplatten und mindestens ein unterhalb des Entnahmebereichs der Siebplatte angeordnetes Trennelement mit einer Trennkante.A further aspect of the invention relates to a separating device for classifying bulk material, comprising at least one of the sieve plates described and at least one separating element with a separating edge arranged below the removal area of the sieve plate.
Vorzugsweise entspricht die Länge des Trennelements der Länge der Entnahmeseite der Siebplatte. Bevorzugt ist der Abstand des Trennelements vom Entnahmebereich variabel.The length of the separating element preferably corresponds to the length of the removal side of the sieve plate. The distance of the separating element from the removal area is preferably variable.
Das Trennelement dient der Abtrennung von Unter- oder Überkorn von der Zielfraktion. Vorzugsweise ist das Trennelement statisch und schwingt nicht mit der Siebplatte mit.The separating element is used to separate undersized or oversized particles from the target fraction. Preferably, the separating element is static and does not vibrate with the sieve plate.
Das Trennelement hat vorzugsweise ein dreieckiges Seitenprofil, insbesondere das Seitenprofil eines spitzwinkligen Dreiecks.The separating element preferably has a triangular side profile, in particular the side profile of an acute-angled triangle.
Die Trennkannte des Trennelements weist vorzugsweise dasselbe Profil wie die Siebplatte auf. Die Trennkannte kann auch geradlinig ausgeführt sein, so dass das Trennelement in Frontansicht die Kontur eines Rechtecks aufweist.The separating edge of the separating element preferably has the same profile as the sieve plate. The separating edge can also be designed to be straight, so that the separating element has the contour of a rectangle in front view.
Das Trennelement ist vorzugsweise um einen Winkel δ schwenkbar. Insbesondere bei höheren Fördergeschwindigkeiten kann dies von Vorteil sein, da sich dann die Fallkurve von großen und kleinen Bruchstücken deutlicher unterscheidet und sich mit einer geschwenkten Trennkante besser der Feinanteil abtrennen lässt. Durch das Schwenken treten deutlich weniger Bruchstücke auf, die vom Trennelement abprallen und ggf. in das Zielprodukt gelangen.
- Fig. 1
- zeigt eine erfindungsgemäße Siebplatte in Draufsicht und Fronansicht.
- Fig. 2
- verdeutlicht die Beschreibung des Profils der Siebplatte.
- Fig. 3
- verdeutlicht die Beschreibung der Öffnungskante der Siebplatte.
- Fig. 4
- zeigt zwei Ausführungsformen der Siebplatte im Bereich der Öffnungskante.
- Fig. 5
- zeigt einen Profilverlauf zur Abtrennung von Unterkorn.
- Fig. 6
- zeigt einen weiteren Profilverlauf zur Abtrennung von Unterkorn.
- Fig. 7
- zeigt einen Profilverlauf zur Abtrennung von Überkorn.
- Fig. 8
- zeigt einen weiteren Profilverlauf zur Abtrennung von Überkorn.
- Fig. 9
- zeigt eine Trennvorrichtung.
- Fig. 10, 11
und 12 - zeigen jeweils eine weitere Ausführungsform der Trennvorrichtung.
- Fig. 1
- shows a sieve plate according to the invention in top view and front view.
- Fig. 2
- clarifies the description of the profile of the sieve plate.
- Fig. 3
- clarifies the description of the opening edge of the sieve plate.
- Fig. 4
- shows two embodiments of the sieve plate in the area of the opening edge.
- Fig. 5
- shows a profile course for separating undersized particles.
- Fig. 6
- shows another profile course for separating undersized particles.
- Fig. 7
- shows a profile course for separating oversize particles.
- Fig. 8
- shows another profile course for separating oversize particles.
- Fig. 9
- shows a separating device.
- 10, 11 and 12
- each show a further embodiment of the separating device.
- 1010
- SiebplatteSieve plate
- 1111
- ProfilbereichProfile area
- 1212
- EntnahmebereichCollection area
- 1313
- Halterungbracket
- 1414
- Erhebungsurvey
- 1515
- Vorsprunghead Start
- 1616
- Vertiefungdeepening
- 1717
- Öffnungskanteopening edge
- 1818
- Öffnungopening
- 1919
- Entnahmeseitewithdrawal side
- 2020
- AufgabebereichArea of responsibility
- 3030
- TrennelementSeparator
- 3232
- TrennkanteSeparating edge
- 4040
- AuffangbehälterCollection container
- 4141
- AuffangbehälterCollection container
- 4242
- AuffangbehälterCollection container
- 5050
- Gebläsefan
- 100100
- TrennvorrichtungSeparating device
In der
Die
Die
Die
Die
Die
Die
Die
Die
Die
Typische Werte für die Siebplatte 10B sind: r1 = 5 mm;
r2 = 25 mm; t = 25 mm, e = 50 mm und α = 45°. Der Winkel δ des Trennelements 30A kann 90° betragen.Typical values for the
r2 = 25mm; t = 25 mm, e = 50 mm and α = 45°. The angle δ of the separating
Die
Generell kann das von einem Polysiliciumhersteller im Beutel angelieferte Polysiliciummaterial auch kleinere Bruchstücke und eine Unterkornfraktion (Unterkorn) enthalten. Das Unterkorn, insbesondere mit Korngrößen kleiner als 4 mm, hat einen negativen Einfluss auf den Ziehprozess bei der Produktion von einkristallinem Silicium und muss aus diesem Grund vor der Verwendung entfernt werden. Für den Test wurde Polysilicium der Bruchgröße 2 (BG 2) eingesetzt.In general, the polysilicon material delivered in a bag by a polysilicon manufacturer may also contain smaller fragments and an undersize fraction (undersize). The undergrain, especially with grain sizes smaller than 4 mm, has a negative influence on the drawing process in the production of single-crystalline silicon and for this reason must be removed before use. Polysilicon with fracture size 2 (BG 2) was used for the test.
Die Größenklasse von Polysiliciumbruchstücken ist als längste Entfernung zweier Punkte auf der Oberfläche eines Siliciumbruchstücks (entspricht der maximalen Länge) definiert:
Das für den Test verwendete Polysiliciummaterial (BG 2) wurde mit einem Analysesieb (gemäß DIN ISO 3310-2) mit einer Nennlochweite W = 4 mm (Quadratlochung) abgesiebt und für die Tests zur Verfügung gestellt. Die abgetrennte Unterkornfraktion (Unterkorn) wurde aufgefangen und gewogen.The polysilicon material (BG 2) used for the test was screened using an analysis sieve (according to DIN ISO 3310-2) with a nominal hole width W = 4 mm (square hole) and made available for the tests. The separated undersize fraction (undersize) was collected and weighed.
Auf eine Fördereinheit wurden 10 kg des Testmaterials (ohne Unterkornfraktion < 4 mm) gegeben. Das Aufgeben des Testmaterials wird bevorzugt über einen Trichter vorgenommen. Der zu füllende Behälter wird am Ende der Siebstrecke über der ersten Fördereinheit positioniert, so dass das Testmaterial ohne Probleme in den Behälter befördert werden kann.10 kg of the test material (without undersize fraction < 4 mm) were placed on a conveyor unit. The test material is preferably added via a funnel. The container to be filled is positioned at the end of the screening section above the first conveyor unit so that the test material can be conveyed into the container without any problems.
Die im Vorfeld abgetrennte Unterkornfraktion wird für diesen Test verwendet. Beim Befüllen der Fördereinheit werden jeweils zu 2 kg Testmaterial 2 g Unterkornfraktion zugegeben, so dass insgesamt ca. 10 g Unterkornfraktion zugegeben wurde.The undersize fraction separated in advance is used for this test. When filling the conveyor unit, 2 g of undersize fraction are added to every 2 kg of test material, so that a total of approx. 10 g of undersize fraction was added.
Die Fördermenge wurde vor dem Testlauf auf 3 kg ± 0,5kg pro Minute eingestellt. Die entfernte Unterkornfraktion wurde aufgefangen und gewogen. Pro Einstellung wurden die Versuche fünfmal vorgenommen.The delivery rate was set to 3 kg ± 0.5 kg per minute before the test run. The removed undersize fraction was collected and weighed. The experiments were carried out five times per setting.
Es wurde eine Fördereinheit mit einer Siebplatte mit konvexer Öffnungskante (gemäß
Es wurde eine Fördereinheit mit einer Siebplatte mit rechteckiger Öffnungskante (gemäß
Es wurde eine Fördereinheit mit einer Siebplatte mit konvexer Öffnungskante (gemäß
Es wurde eine Fördereinheit mit einer Siebplatte mit konvexer Öffnungskante (gemäß
Tabelle 1 zeigt die mittleren Ergebnisse im Vergleich zu den Ergebnissen aus der
Das vom Polysiliciumhersteller im Beutel angelieferte Polysiliciummaterial darf keine zu großen Bruchstücke (Überkorn) enthalten. Das Überkorn kann zu Verstopfungen und Beschädigungen führen und muss deshalb vor der Verwendung entfernt werden. Für den Test wurde die BG 2 eingesetzt.The polysilicon material delivered in the bag by the polysilicon manufacturer must not contain any excessively large fragments (oversize particles). The oversize can cause blockages and damage and must therefore be removed before use. The
Aus dem für den Test verwendeten Polysiliciummaterial (BG 2) wurden manuell alle Überkorn-Bruchstücke entfernt. Das entfernte Überkornmaterial wurde aufgehoben und gewogen.All oversize fragments were manually removed from the polysilicon material (BG 2) used for the test. The removed oversize material was saved and weighed.
Auf die Fördereinheit wurden 10 kg des Testmaterials ohne Überkorn gegeben. Das Aufgeben wurde über einen Trichter vorgenommen. Der zu füllende Behälter wird am Ende der Siebstrecke über der ersten Fördereinheit positioniert, so dass das Testmaterial in den Behälter befördert werden kann.10 kg of the test material without oversize was placed on the conveyor unit. Posting was done via a funnel. The container to be filled is positioned at the end of the screening section above the first conveyor unit so that the test material can be conveyed into the container.
Beim Befüllen der Fördereinheit werden jeweils zu 2 kg Testmaterial 100 g des abgetrennten Überkorns zugegeben, so dass insgesamt 500 g Überkorn zugegeben wurde.When filling the conveyor unit, 100 g of the separated oversize are added to every 2 kg of test material, so that a total of 500 g of oversize was added.
Die Fördermenge wurde vor dem Testlauf auf 15 kg ± 1 kg pro Minute eingestellt. Das entfernte Überkorn wurde aufgefangen und gewogen. Pro Einstellung wurden die Versuche fünfmal vorgenommen.The delivery rate was set to 15 kg ± 1 kg per minute before the test run. The removed oversize was collected and weighed. The experiments were carried out five times per setting.
Es wurde eine Fördereinheit mit einer Siebplatte mit konvexer Öffnungskante (gemäß
Es wurde eine zweifach hintereinandergeschaltete Trennvorrichtung gemäß
Es wurde eine vierfach hintereinandergeschaltete Trennvorrichtung gemäß
Es wurde eine Fördereinheit mit einer Siebplatte mit konvexer Öffnungskante (gemäß
Tabelle 2 zeigt die mittleren Ergebnisse zur Überkornabtrennung:
Claims (11)
- Screen plate (10) for removing undersize for a separating device (100) for classifying bulk material, comprising a profile region (11) which has a profile having depressions (16) and elevations (14) extending in the direction of a takeoff side (19), where the profile is describable by a circle arc of a first circle K1 and by a circle arc of a second circle K2, and the circles K1 and K2 are disposed adjacent to one another, where the circle arc of the first circle K1 with a radius r1 describes the elevations (14) and the circle arc of the second circle K2 with a radius r2 describes the depressions (16), with each depression (16) in a takeoff region (12) undergoing transition into an opening (18) which expands in the direction of the takeoff side (19), where the transition between depression (16) and opening (18) is formed by an opening edge (17) with a width corresponding to the length of the radius r2 to 2*r2, where either- r1 + r2 = e, where e corresponds to the distance between the circle center point M1 of K1 and the circle center point M2 of K2, and K1 and K2 contact one another at a point T0 at which the circle arcs merge, and where 0° < α < 65°, where α is an angle which defines the position of M2 relative to M1 in a cartesian coordinate system, if M1 and M2 are vertices of a right-angled triangle and e corresponds to the hypotenuse of the triangle; or- r1 + r2 < e and K1 and K2 do not contact one another, where the circle arcs are joined to one another by a common tangent through a point T1 of K1 and a point T2 of K2, and where -65° < α < 65°,characterized in that the profile is subject to r2 < r1, with 0 < r2/r1 < 1.
- Screen plate according to Claim 1, characterized in that when r1 + r2 = e, the angle α is subject to 0° < α < 25°, preferably 5° < α < 20°.
- Screen plate according to Claim 1, characterized in that when r1 + r2 < e, the angle α is subject to -25° < α < 10°, preferably -10° < α < 5°.
- Screen plate according to any of the preceding claims, characterized in that r2/r1 is subject to 0.2 < r2/r1 < 0.4.
- Screen plate (10) for removing oversize for a separating device (100) for classifying bulk material, comprising a profile region (11) which has a profile having depressions (16) and elevations (14) extending in the direction of a takeoff side (19), where the profile is describable by a circle arc of a first circle K1 and by a circle arc of a second circle K2, and the circles K1 and K2 are disposed adjacent to one another, where the circle arc of the first circle K1 with a radius r1 describes the elevations (14) and the circle arc of the second circle K2 with a radius r2 describes the depressions (16), with each depression (16) in a takeoff region (12) undergoing transition into an opening (18) which expands in the direction of the takeoff side (19), where the transition between depression (16) and opening (18) is formed by an opening edge (17) with a width corresponding to the length of the radius r2 to 2*r2, where either- r1 + r2 = e, where e corresponds to the distance between the circle center point M1 of K1 and the circle center point M2 of K2, and K1 and K2 contact one another at a point T0 at which the circle arcs merge and where - 65° < α < 0°, where α is an angle which defines the position of M2 relative to M1 in a cartesian coordinate system, if M1 and M2 are vertices of a right-angled triangle and e corresponds to the hypotenuse; or- r1 + r2 < e and K1 and K2 do not contact one another, where the circle arcs are joined to one another by a common tangent through a point T1 of K1 and a point T2 of K2, and where -65° < α < 65°,characterized in that the profile is subject to r2 > r1, with 0 < r1/r2 < 1.
- Screen plate according to Claim 5, characterized in that rl/r2 is subject to 0.2 < rl/r2 < 0.4.
- Screen plate according to Claim 5 or 6, characterized in that the angle α is subject to -20° < α < 0°.
- Screen plate according to any of the preceding claims, characterized in that the opening edge (17) has a concave extent and has a depth t for which 0 < t ≤ 5*r2, preferably r2 to 5*r2, more preferably r2 to 4*r2, more particularly 2*r2 to 3*r2.
- Screen plate according to any of Claims 1 to 7, characterized in that the opening edge (17) has a rectangular extent and has a depth t for which 0 < t ≤ 5*r2, preferably r2 to 5*r2, more preferably r2 to 4*r2, more particularly 2*r2 to 3*r2.
- Separating device (100) for classifying bulk material, comprising at least one screen plate (10) according to at least one of Claims 1 to 9 and at least one separating element (30) disposed beneath the takeoff region (12) of the screen plate (10) and having a separating edge (32), characterized in that the separating edge (32) of the separating element (30) has a profile like the screen plate (10).
- Separating device according to Claim 10, characterized in that the separating element (30) is swivelable by an angle δ.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/EP2020/073597 WO2022042815A1 (en) | 2020-08-24 | 2020-08-24 | Screen plate for a separating device for classifying bulk material |
Publications (2)
Publication Number | Publication Date |
---|---|
EP4200085A1 EP4200085A1 (en) | 2023-06-28 |
EP4200085B1 true EP4200085B1 (en) | 2024-01-10 |
Family
ID=72240427
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP20761555.0A Active EP4200085B1 (en) | 2020-08-24 | 2020-08-24 | Screen plate for a separating device for classifying bulk material |
Country Status (7)
Country | Link |
---|---|
US (1) | US11904361B2 (en) |
EP (1) | EP4200085B1 (en) |
JP (1) | JP2023542482A (en) |
KR (1) | KR20230038788A (en) |
CN (1) | CN116096509A (en) |
TW (1) | TWI808472B (en) |
WO (1) | WO2022042815A1 (en) |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
PL327664A1 (en) | 1996-01-18 | 1998-12-21 | Siemens Ag | Unloading apparatus |
DE19822996C1 (en) * | 1998-05-22 | 1999-04-22 | Siemens Ag | Temperature-resistant gradient material for heat shield or gas turbine blade |
DE19945037A1 (en) | 1999-09-20 | 2001-03-29 | Hubertus Exner | Device for aligning and, if necessary, sorting elongated particles |
DE102012220422A1 (en) | 2012-11-09 | 2014-05-15 | Wacker Chemie Ag | Packaging of polycrystalline silicon |
DE102015211351A1 (en) * | 2015-06-19 | 2016-12-22 | Siltronic Ag | Sieve plate for screening equipment for the mechanical classification of polysilicon |
DE102016225248A1 (en) | 2016-12-16 | 2018-06-21 | Siltronic Ag | Separator for polysilicon |
JP6588937B2 (en) | 2017-04-28 | 2019-10-09 | 株式会社ミツワ | Bean sorting machine with strawberries |
CN207605973U (en) | 2017-11-10 | 2018-07-13 | 苏州鸿博斯特超净科技股份有限公司 | Polysilicon shaking-sieving device |
-
2020
- 2020-08-24 CN CN202080103379.2A patent/CN116096509A/en active Pending
- 2020-08-24 KR KR1020237005686A patent/KR20230038788A/en active Search and Examination
- 2020-08-24 EP EP20761555.0A patent/EP4200085B1/en active Active
- 2020-08-24 JP JP2023513143A patent/JP2023542482A/en active Pending
- 2020-08-24 WO PCT/EP2020/073597 patent/WO2022042815A1/en unknown
- 2020-08-24 US US18/022,528 patent/US11904361B2/en active Active
-
2021
- 2021-08-19 TW TW110130744A patent/TWI808472B/en active
Also Published As
Publication number | Publication date |
---|---|
JP2023542482A (en) | 2023-10-10 |
CN116096509A (en) | 2023-05-09 |
US20230311165A1 (en) | 2023-10-05 |
TWI808472B (en) | 2023-07-11 |
WO2022042815A1 (en) | 2022-03-03 |
KR20230038788A (en) | 2023-03-21 |
EP4200085A1 (en) | 2023-06-28 |
TW202212002A (en) | 2022-04-01 |
US11904361B2 (en) | 2024-02-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP3310499B1 (en) | Process for the mechanical classifying of polysilicon | |
EP3043929B1 (en) | Classification of polycrystalline silicon | |
EP1842595B1 (en) | Method and device for comminuting and sorting polysilicon | |
EP2001607B1 (en) | Device and method for the flexible classification of polycrystalline silicon fragments | |
EP2666750B1 (en) | Polycrystalline silicon | |
EP2903755B1 (en) | Apparatus and method for classifying polydisperse materials | |
EP2055395B1 (en) | Method and device for sieving out particles | |
EP1645333A1 (en) | Device and method for low-contaminating, automatic breaking of silicon fragments | |
EP2730510B1 (en) | Method for packaging of polycrystalline silicon | |
AT516406B1 (en) | Device for separating coarse grain from smaller grain sizes | |
EP4200085B1 (en) | Screen plate for a separating device for classifying bulk material | |
EP3554723B1 (en) | Separating device for polycrystalline silicon | |
DE102011107643A1 (en) | Cigarette decomposing apparatus for filter cigarettes and cigarette breaking machine and method for cutting a filter cigarette | |
DE102023102854B3 (en) | Device and method for flexible classification of poly- and/or monocrystalline silicon | |
DE10104103C1 (en) | Method of separating solid components from waste material from cutting machines entails transporting material over first separating unit to remove chips, and then over second separating device to remove solid components | |
DD154069A1 (en) | DEVICE FOR CLASSIFICATION OF METAL SPARE SCRAP AND HETEROGUE SHOE |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: UNKNOWN |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20230131 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTG | Intention to grant announced |
Effective date: 20231011 |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
P01 | Opt-out of the competence of the unified patent court (upc) registered |
Effective date: 20231110 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D Free format text: NOT ENGLISH |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 502020006704 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D Free format text: LANGUAGE OF EP DOCUMENT: GERMAN |
|
REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG9D |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: MP Effective date: 20240110 |