Separator, separator mill and method for separating a gas-solids mixture

Abstract

A separator having a separator housing, a separator wheel arranged inside the separator housing and having an axis of rotation (X), and a guide vane assembly arranged in the separator housing, an annular space being provided between the guide vane assembly and the separator housing radially (R) perpendicular to the axis of rotation (X). In order to increase separation performance, a peripheral annular gap is provided in the vertical direction between the guide vane assembly and a cover.

Claims

1. A separator, comprising: a separator housing, a separator wheel arranged inside the separator housing and having an axis of rotation (X), and a guide vane assembly non-rotably arranged in the separator housing, an annular space being provided between the guide vane assembly and the separator housing radially (R) perpendicular to the axis of rotation (X), wherein a peripheral annular gap is provided in a vertical direction between the guide vane assembly and a cover.

2. The separator as claimed in claim 1, wherein the annular gap has a height (HR), while the guide vane assembly and/or the cover are movable in the direction of the axis of rotation (X), so that the height (HR) is adjustable.

3. The separator as claimed in claim 2, wherein the height (HR) is between 50 mm and 1000 mm.

4. The separator as claimed in claim 1, wherein the cover is a housing cover or a separator cover.

5. The separator as claimed in claim 4, wherein the separator cover is connected to the separator wheel, so that the separator cover rotates with the separator wheel.

6. The separator as claimed in claim 1, wherein the annular space tapers toward the top.

7. The separator as claimed in claim 1, wherein the annular space has a width (B), and the ratio B:HR is between 0.2 and 5.

8. The separator as claimed in claim 1, wherein the guide vane assembly has a height (HL), and the ratio HL:HR is between 0.5 and 10.

9. The separator as claimed in claim 1, wherein the guide vane assembly has a plurality of vertical guide vanes, wherein at least one deflecting element is arranged between at least two guide vanes, having at least one downwardly directed curvature or bending.

10. The separator as claimed in claim 9, wherein the deflecting elements extend over an entire width between two neighboring guide vanes.

11. The separator as claimed in claim 9, wherein at least one of the deflecting elements extends from the guide vane assembly into a separating zone and/or into the annular space.

12. The separator as claimed in claim 9, wherein at least one of the deflecting elements has a variable radius of curvature in a partial section in the radial direction (R) of the guide vane assembly.

13. The separator as claimed in claim 1, wherein the guide vane assembly has at least one swirl breaker.

14. A mill having an integrated separator as claimed in claim 1.

15. A method for separating a gas-solids mixture, comprising the following steps: introducing an inlet volume flow (Q) from a gas-solids mixture into a separator with a separator wheel, a guide vane assembly and a separating zone arranged between the separator wheel and the guide vane assembly; apportioning the inlet volume flow (Q) into a first partial volume flow (Q1) and a second partial volume flow (Q2); introducing the first partial volume flow (Q1) into the separating zone bypassing the guide vane assembly; and introducing the second partial volume flow (Q2) into the separating zone through the guide vane assembly.

16. The method for separating a gas-solids mixture as claimed in claim 15, wherein the first partial volume flow (Q1) is introduced into the separating zone from above.

17. The method for separating a gas-solids mixture as claimed in claim 15, wherein the first partial volume flow (Q1) or the second partial volume flow (Q2) is introduced into the separating zone substantially in the direction of the force of gravity (F).

18. The method for separating a gas-solids mixture as claimed in claim 15, wherein the ratio Q1:Q2 between the first partial volume flow (Q1) and the second partial volume flow (Q2) is between 20:80 and 80:20.

19. The method for separating a gas-solids mixture as claimed in claim 15, wherein the two partial volume flows (Q1, Q2) are guided such that they meet each other in the separating zone at an angle (φ), where: 45°<φ<135°.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention shall be represented and explained with the aid of the figures as an example. There are shown:

(2) FIG. 1 a schematic side view of a separator in cross section;

(3) FIG. 2 a mill with integrated separator per FIG. 1 in cross section;

(4) FIG. 3 a schematic side view of the upper section of the separators of FIG. 1 partly in cross section;

(5) FIG. 4 a schematic side view of a separator according to a further embodiment in cross section;

(6) FIG. 5 a guide vane assembly in perspective representation;

(7) FIG. 6 the guide vane assembly of FIG. 5 in a top view;

(8) FIG. 7 an enlarged cut-out of the guide vane assembly shown in FIGS. 5 and 6;

(9) FIGS. 8-14 different embodiments of deflecting elements in side view;

(10) FIG. 15 a diagram with summary distributions plotted against particle sizes.

DETAILED DESCRIPTION OF THE INVENTION

(11) FIG. 1 shows a separator 10. The separator 10 comprises a separator housing 20. In a lower region, the separator housing 20 has an inlet 21 for a volume flow Q of a gas-solids mixture 100.

(12) In the separator housing 20 there are arranged a separator wheel 30 and a guide vane assembly 50. The separator wheel 30 and the guide vane assembly 50 have a common principal axis, which is the axis of rotation X for the separator wheel 30. The axis of rotation X extends in the direction of the force of gravity F. Perpendicular to the axis of rotation X extends a radial direction R. Between the guide vane assembly 50 and the separator housing 20, an annular space 26 is provided in the radial direction R. The space between the separator wheel 30 and the guide vane assembly 50 forms the separating zone 32.

(13) The separator wheel 30 is driven in rotation by a drive device 40, so that the separator wheel 30 turns about the axis of rotation X.

(14) Between the guide vane assembly 50 and a housing cover 24 there is situated an annular gap 28. The volume flow Q entering the annular space 26 from below is apportioned into two partial volume flows Q1 and Q2, whereby the partial volume flow Q1 passes through the annular gap 28 and gets into the separating zone 32 from above. The partial volume flow Q2 flows through the guide vane assembly 50 and in this way gets into the separating zone 32. Thus, the two partial volume flows Q1 and Q2 meet once more in the separating zone 32.

(15) Above the separator wheel 30 there is arranged a first outlet 22. The first outlet 22 is connected to a suction mechanism (not shown), which creates a negative pressure. A first particle variety 101, the fine material, is sucked through the first outlet 22 when the device is used as intended.

(16) Beneath the separator wheel 30 there is arranged a funnel 25. The funnel 25 empties into a second outlet 23. A second particle variety 102, the coarse material, is taken away through the second outlet 23 when the device is used as intended. The separator wheel 30 rejects large particles 102. These large particles get into the funnel 25 and from there go to the second outlet 23.

(17) The separator housing 20 is closed at the top end by a housing cover 24.

(18) FIG. 2 shows a mill 110, which is designed as a pendulum mill. Inside the housing 112, which is closed off on top by a mill cover 114 and at the bottom by means of a mill floor 116, there is located a milling mechanism 118, comprising several milling pendulums 120. Through the milling mechanism 118, the separator 10 is integrated into the mill housing. Between the mill housing 112 and the guide vane assembly 50 there is situated the annular space 26. The annular gap 28 is located between the guide vane assembly 50 and the mill cover 114.

(19) FIG. 3 shows the top part of the separator 10. The separator wheel 30 is situated inside the guide vane assembly 50. Between the separator wheel 30 and the guide vane assembly 50 there is situated a separating zone 32. The cylindrical separator housing 20 can also be conical in design. With such a conical separator housing 20′ (shown by broken line), an upwardly tapering annular space 26 is formed.

(20) Likewise shown in broken lines is a modification of the housing cover. The housing cover 24′ is vaulted at the top, which favors the deflecting of the partial volume flow Q1.

(21) The encircling annular gap 28 is present between the guide vane assembly 50 and the housing cover 24 in the vertical direction. The annular gap 28 has a height HR. The annular space 26 has a width B. In the embodiment shown, the ratio B:HR is around 1.

(22) The guide vane assembly 50 has a height HL. In the embodiment shown, the ratio HL:HR is around 3.5.

(23) The first outlet 22 communicates with the interior space of the separator wheel 30.

(24) The guide vane assembly 50 has a multitude of vertical guide vanes 54. Five deflecting elements 53 are arranged between neighboring vertical guide vanes 54, each of them having a downwardly pointing curvature.

(25) A top edge 34 of the separator wheel 30 is located above the top edge 56 of the guide vane assembly 50. More than 50% of the annular gap 28 in the vertical direction is located entirely above the top edge 34 of the separator wheel 30.

(26) The volume flow Q of the gas-solids mixture 100 flows from the bottom into the annular space 26. A first partial volume flow Q1 can flow through the annular gap 28. The first partial volume flow Q1 gets into the separating zone 32 from above in this way. A second partial volume flow Q2 flows through the guide vane assembly 50 into the separating zone 32 and impinges on the first partial volume flow Q1 there. The deflecting elements 53 impart flow components directed at the separator wheel to the gas-solids mixture flowing through the guide vane assembly 50, as indicated by the arrows drawn. The partial volume flows Q1, Q2 meet at an angle φ (see the enlarged partial representation in FIG. 3). The angle φ in the embodiment shown is around 45°.

(27) For reasons of clarity, Q2 indicates only one possible flow path for a partial stream of the second partial volume flow Q2. However, the second partial volume flow Q2 in its entirety designates the total volume flow moving from the annular space 26 through the guide vane assembly 50 into the separating zone 32.

(28) Fine particles 101 move from the separating zone 32 into the interior of the separator wheel 30 and are sucked through the first outlet 22.

(29) FIG. 4 shows another embodiment of a separator 10. The separator 10 comprises a separator housing 20 with an inlet 21, a first outlet 22 and a second outlet 23. In the separator housing 20 there are arranged a separator wheel 30 and a guide vane assembly 50. The separator wheel is driven in rotation.

(30) The separator wheel 30 comprises a separator cover 36. The separator cover 36 has the form of an annular disc. In the middle of the separator cover 36 is situated an opening 38. Through the opening 38, material can flow from the interior of the separator wheel 30 to the first outlet 22.

(31) The separator cover 36 rotates with the separator wheel 30. An encircling annular gap 28 is provided between the separator cover 36 and the guide vane assembly 50 in the vertical direction.

(32) The guide vane assembly 50 is outfitted with a further configuration of the deflecting elements 53, having a bend. Furthermore, the deflecting elements 53 extend into the annular space 26.

(33) FIG. 5 shows the guide vane assembly 50 of FIG. 3 in a perspective representation. FIG. 6 shows a top view of the guide vane assembly 50 represented in FIG. 5.

(34) The guide vane assembly 50 has a plurality of vertical guide vanes 54, with five deflecting elements 53 being arranged between every two neighboring guide vanes 54. Each deflecting element 53 extends across the entire width between two vertical guide vanes 54. The deflecting elements 53 are arranged equidistant in the vertical direction.

(35) On its outer circumferential surface the guide vane assembly 50 has a multitude of swirl breakers 52, unlike the guide vane assembly 50 of FIG. 3. The swirl breakers 52 protrude into the annular space 26 and oppose a flow in the circumferential direction. The swirl breakers 52 have a rectangular basic form and are made of sheet metal. The swirl breakers 52 stand off in the radial direction R from the guide vane assembly 50 and extend across the entire height of the guide vane assembly.

(36) FIG. 7 shows an enlarged cut-out of the guide vane assembly 50 represented in FIG. 5.

(37) The deflecting elements 53 have a downwardly pointing curvature. Each deflecting element 53 has a radial inner end 55 and a radial outer end 56. The radial inner ends 55 do not protrude into the separating zone 32 in the embodiment shown.

(38) A first end section 57 is arranged at the radial inner end 55 of each deflecting element 53 and a second end section 58 is arranged at the radial outer end 56 of each deflecting element 53. The two end sections 57, 58 are curved.

(39) FIGS. 8 to 14 show different embodiments of a deflecting element 53. The deflecting elements 53 each have a radial inner end 55 and a radial outer end 56. The radial inner end 55 has a first end section 57 and the radial outer end 56 has a second end section 58. The deflecting elements 53 have a downwardly directed curvature (see FIGS. 8 to 12) or a downwardly directed bend (see FIGS. 13 and 14).

(40) The deflecting elements 53 are arranged relative to an axis of rotation X of the separator wheel (not shown here), the spacing between deflecting element 53 and axis of rotation X being shown smaller here for drawing reasons.

(41) The embodiments shown in FIGS. 8 to 14 differ in particular in the configuration of the end sections 57, 58. The end sections 57, 58 may both be curved (see FIGS. 8 to 10) or both be straight (see FIGS. 12 and 14), while also straight and/or curved end sections may be joined together across a curved middle section. FIGS. 13 and 14 show deflecting elements 53 with bends.

(42) The first end section 57 of each deflecting element 53 or its tangential prolongation (see FIG. 11) is situated at an angle γ to the horizontal H. The angle γ in the embodiments shown is between 0° (see FIG. 8) and around 28° (see, e.g., FIG. 12). The horizontal H, which corresponds to the radial direction R, makes a right angle with the axis of rotation X.

(43) The second end section 58 of each deflecting element 53 or its tangential prolongation (see FIGS. 8, 9, 11, 12) is situated at an angle α to the horizontal H. The angle α in the embodiments shown is between around 35° (see, e.g., FIG. 9) and around 65° (see FIG. 8).

(44) The first end section 57 and the second end section 58 of a deflecting element 53 or its tangential prolongations make an angle β. The angle β in the embodiments shown is between around 108° (see FIG. 12) and around 153° (see FIG. 10).

(45) The angles α, β and γ in the embodiments shown add up to 180°. With the exception of angle γ in FIG. 10, all angles α, β, γ point downward.

(46) FIG. 15 shows a diagram of summary distributions plotted against particle sizes. The distributions of two separations are shown, a first distribution V1 and a second distribution V2. The first distribution V1 is designated by dots, the second distribution V2 by triangles. In the first distribution V1, a separator was used without an annular gap. The second distribution V2, on the other hand, shows the result of a separation making use of a separator with an annular gap.

(47) Identical starting material was used in the two separations.

(48) For identical starting material, it basically holds that a steeper curve should be evaluated more positively than a curve which is less steep. The desired result of a sorting process is generally the fine material. In the case of using the separator according to the invention in a separation mill, for example, the fine material is removed and the coarse material is returned to the mill, in order to be crushed further or crushed again. Particles actually belonging to the fine material, yet ending up in the coarse material, cost extra time and energy, since they need to run through the mill cycle once again. Particles actually belonging to the coarse material, yet ending up in the fine material, are much more disruptive, since they have direct negative impact on the quality of the end product (the fine material). Therefore, for the same starting material, a sorting with smaller fines fraction is positive. In the first distribution V1, the sum of the particles which are less than 2 μm is 0.344. Thanks to the use of an annular gap (second distribution V2), this fraction can be lowered by around 10% to 0.312. Especially in the region of larger particle sizes (>3 μm), the second distribution V2 is found to be more steep and therefore advantageous.

LIST OF REFERENCE SYMBOLS

(49) 10 Separator 20 Separator housing 20′ Conical separator housing 21 Inlet 22 First outlet 23 Second outlet 24 Housing cover 24′ Curved housing cover 25 Funnel 26 Annular space 28 Annular gap 30 Separator wheel 32 Separating zone 34 Top edge 36 Separator cover 38 Opening 40 Drive device 50 Guide vane assembly 52 Swirl breaker 53 Deflecting element 54 Guide vane 56 Top edge 100 Gas-solids mixture 101 First particle variety (fine) 102 Second particle variety (coarse) B Width of annular space F Force of gravity H Horizontal HL Height of guide vane assembly HR Height of annular gap Q Inlet volume flow Q1 First partial volume flow Q2 Second partial volume flow R Radial direction V1 First distribution V2 Second distribution X Axis of rotation α Angle β Angle γ Angle δ Angle