TWI571516B - Distribution chute and metallurgical reactor comprising the distribution chute - Google Patents

Description

Distribution chute and metallurgical reactor containing the distribution chute

The present invention relates generally to a dispensing chute for use in a bulk material dispensing apparatus for dispensing bulk material in a closed casing such as a metallurgical reactor and particularly a blast furnace. More specifically, the present invention relates to a dispensing chute having a chute body defining a passage with a curved portion that diverts bulk material from a first flow direction to a second flow In the direction, after the bulk material hits the chute along the first flow direction, it immediately flows into an inlet portion of the chute, and the bulk material flow exits the chute outlet in the second flow direction.

In the specific case of the blast furnace, it has been found that a so-called "bell-less" type of charging device is widely used. Such charging devices are disposed on the roof of the furnace and include a dispensing device and a distribution chute as an important component. The dispensing device is typically assembled to rotate the chute about an upright furnace axis and to pivot the chute about a vertical horizontal axis. During the charging process, the bulk packing falls vertically on the dispensing chute, which distributes the material circumferentially and radially depending on its rotational and pivotal position. Thus, any desired loading material distribution pattern can be achieved on the surface of the charge.

Due to the scraping action of a large amount of bulk material sliding through a dispensing chute, the chute suffers considerable wear and must often be replaced with a new or refurbished chute. A fairly common chute design is known, for example, from European Patent EP 0 640 539. This patent teaches a longitudinally straight and generally slotted chute body having a plurality of special retaining chambers that retain a layer of bulk material on the chute to minimize wear.

When the chute is not in a nearly vertical (central loading) position, one effect of deteriorating the wear of the chute is that the material impinges on the chute at a relatively large angle. In other words, in the case of a typical charge distribution pattern, most of the pivoting positions of the chute exert a comparable impact load which adds sliding friction as a cause of scratch wear. In fact, in the case of a typical straight straight chute as proposed in European Patent No. EP 0 640 539, the angle of impact of the material on the chute is equivalent to the angle of inclination of the chute, for the radially outermost loading Material position, which may be much higher than 50° (from vertical).

In order to reduce the wear of the most wear-prone portion, i.e., the impact portion of the chute, it has thus been proposed to provide a chute body that differs from a typical straight shape. Briefly, in the chutes, the impact portion forms a sharper angle with respect to the outlet portion in the vertical drop direction, which determines the degree of radial flow deviation (loading radius). In other words, after the impact, the direction of the flow is generally steeper than the direction of flow in the outlet. Therefore, such a chute almost achieves the same flow deviation while significantly reducing the impact load. Moreover, when struck at a sharper angle, the flow is slowed to a lesser extent. Thus, in another advantage, the material has a higher exit velocity at the outlet such that the chute can achieve the same loading radius with a shorter chute length or with a smaller angle of chute inclination. The wear is further reduced by the latter option.

Defining a distribution chute body having a passageway with a curved portion that rapidly deflects the flow from a first flow direction to a second flow that is less steep at one of the outlets after impacting the chute The direction of the flow is known, for example, from Japanese Patent Application No. 59-020412 and JP-A-59-031807.

JP 59-020412 proposes a generally trough-shaped chute body having a generally flat downstream portion (Fig. 2: AB) and an upstream portion bent into an arc (Fig. 2: CB) The arc has a center of curvature which is a radius of 0.5 to 4.0 times, more preferably 0.5 to 3.0 times the length of the chute. Therefore, the flow of the filling material gradually changes its direction along the curved shape of the chute. However, the manufacture of such a curved shape is not economical or is likely to result in a rather fragile structure. JP 59-031807 proposes a very similar design. The groove-shaped chute body differs only in that the upstream portion is formed by a plurality of continuous straight segments which are in tangential contact with a curved arc having a length of the chute A radius of 0.5 to 4.0 times. Therefore, the sections proposed in JP 59-031807 approximate the curved shape of the aforementioned JP 59-020412, and are likely to be economically advantageous in terms of manufacturing.

Another chute body proposed in WO 2009/037508 has a downstream portion that is less steep than the upstream portion. The latter-described chute has a frusto-conical structure in one body and is particularly suitable for a so-called ring-type type of charging device in which the chute is wound around two mutually perpendicular horizontal axes. The pivoting of the joint is pivoted. In addition to being incompatible with rotating and pivoting loading devices, this chute is considered to be subject to faster wear at the point of impact.

Although they have the distinct advantage of increasing service life due to reduced wear and possibly shorter chute lengths, the distribution chute with progressive material flow deviation as discussed above has not been at least in the field of metallurgical reactors. broadly used.

In theory, the lack of such acceptance is particularly due to the difficulties associated with providing a structure for the chute body that is both economical and of sufficient strength to reliably resist application to the chute. The equivalent load, including the weight of the filling material and the dynamic load applied during the rotation and pivoting of the chute.

It is therefore an object of the present invention to provide a dispensing chute of the type having a robust and cost effective structure having a chute body defining a flow passage with a curved upstream portion.

The invention of the present invention proposes a shifting and pivoting type of distribution chute. It can be used in a bulk material dispensing device, particularly for a filling material dispensing device such as a blast furnace metallurgical reactor. The distribution chute includes a chute body (that is, a load supporting structure of the distribution chute), and has a passage with an inlet and an outlet for receiving one of the bulk materials, and the outlet is used for the outlet The bulk material is discharged. In operation, the passage carries the bulk material from the inlet to the outlet. The passage has a bend for diverting the flow of material from a first flow direction of the inlet to a second flow direction of the outlet. According to the invention, the chute system has at least an upstream portion and a downstream portion, the upstream portion includes the inlet, and the downstream portion includes the outlet, and the upstream portion is fixed to the upstream portion (ie, the upstream portion and the downstream portion) Be tightened to prevent relative displacement). The downstream portion defines a straight portion of the passage and the upstream portion defines the inlet and the bend of the passage. Furthermore, the upstream portion is thicker relative to the (thinner walled) downstream portion.

Those skilled in the art will appreciate that in such a distribution chute, the bulk portion of the load applied by the impacted bulk material to the distribution chute is received by the upstream portion of the thick wall of the chute body. . Since the upstream portion of the chute also includes the bent portion, a majority of the steering force required to change the track of the bulk material in the transition region between the first and second flow directions is also It is applied by the upstream portion. In the downstream portion of the chute, the material follows a substantially linear track (in the reference system of the chute). Therefore, the wall strength of the downstream portion has been selected to be smaller than the wall strength of the upstream portion. The result is a distribution chute having a high structural rigidity, based on a radially outwardly directed downstream portion, which exerts less torque on the chute bearing and which is economical to manufacture.

As used herein, the first flow direction corresponds to the overall tangential direction of the bottom of the inlet (in the vertical center plane of the distribution chute), at least for a high discharge angle, ie, about 45° high, bulk material The flow impinges on the distribution chute at the bottom, and the second flow direction corresponds to the overall tangential direction of the bottom of the outlet (in the vertical center plane of the distribution chute). As used herein, the term "discharge angle" means the angle between the distribution chute outlet and the vertical direction.

According to a preferred embodiment of the invention, the upstream portion is made of cast metal such as cast iron or cast steel. Those skilled in the art will appreciate that the use of casting techniques can provide versatility in terms of the shape of the upstream portion. In other words, the design of the chute is less restrictive than prior designs in the prior art, which makes it easier to modify the chute body, available space, and other parameters in accordance with the application. Most preferably, the downstream portion includes one or more curved steel plates that are welded.

The inlet of the passage of the distribution chute is preferably provided as an annular collar on the upstream portion. The inlet is thus formed as a tubular section (which encloses the axis of the inlet in a circular manner). The annular collar strengthens the upstream portion to withstand higher torsion without significant deformation.

According to a preferred embodiment of the dispensing chute, the downstream portion includes a tubular section providing the outlet. As will be appreciated by those skilled in the relevant art, this reduces (or eliminates) the lateral overflow of the bulk material, which ultimately results in improved control of the charge distribution under the chute. Most preferably, the downstream portion tapers towards the outlet from the junction to which the upstream portion is attached.

Preferably, the channel has a first channel axis in the inlet (corresponding to the first flow direction) and a second channel axis in the outlet (corresponding to the second flow direction), etc. The bend in the upstream portion defines an angle. This angle is preferably in the range of 15 to 45, more preferably in the range of 20 to 40.

The bend in the upstream portion may be steep (steep). Alternatively, the bend may define a curved transition region between the inlet and the bottom of the channels in the outlet. It should be appreciated that the use of casting techniques for the manufacture of the upstream portion can be easily achieved on all surfaces that are curved in three dimensions.

To combine the upstream portion with the downstream portion, the upstream portion includes a coupling end facing the inlet (in the case of the bend). The downstream portion is preferably inserted into the coupling end, for example up to the bend, and secured in this position using screws, bolts, rivets, welds or any other suitable securing mechanism. To achieve high stability, the length of the overlapping portion of the joining end portion and the downstream portion is preferably at least 20% of the total length of the downstream portion, for example between 20% and 40%.

According to a preferred embodiment of the present invention, the dispensing chute includes an insert in the upstream portion and/or in the downstream portion, the insert including a plurality of holding chambers (stone boxes), which are opened To the passage, to fill the bulk material used to protect the dispensing chute from wear. Preferably, the inserts are configured such that the incoming flow of bulk material may be protected by a stone chamber at any surface upon which it may impinge at an angle of at least about 30°. This approach ensures that the areas of the channel surface that are most susceptible to corrosion by the impact material flow are suitably protected. It should be appreciated that the insert can be individually replaced from the chute body when it has been worn. This helps keep maintenance costs low. It should be noted that in addition to the insert in the form of a retaining chamber, it is also possible to provide inserts in the form of castings or ceramic wear plates.

Preferably, the outlet of the distribution chute is formed by a wear resistant sliding insert in the downstream portion. The slider has a substantially smooth surface in the outlet as compared to the region in which each of the retention chambers is disposed to expel a concentrated and uniform flow of bulk material as much as possible.

Preferably, the chute body has an opening on the inner side of the bent portion. An advantage of such an opening is that, for example, the weight reduction of the chute does not compromise wear resistance, and when the chute is oriented substantially perpendicular to the center charge (ie, when the discharge angle is less than about 15) °) does not impair the removal of an "obstacle" into the incoming material of the bulk material.

The dispensing chute can include operational trunnions on the upstream portion that can be supported by a tilting mechanism or the like. The operational trunnions are preferably integrally formed with the upstream portion.

A preferred aspect of the present invention relates to a metallurgical reactor, such as a blast furnace, comprising a charging device with a filling material dispensing device, the filling material dispensing device being provided with a dispensing chute as described herein.

Further details and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments.

The same element symbols are used in the drawings to identify the same functionally similar components or elements.

A dispensing chute 10 in accordance with a preferred embodiment of the present invention is generally shown in FIG. The distribution chute 10 includes a chute body 12 that is substantially constructed of two structural components: a cast steel upstream portion 14 and a downstream portion 16 formed from a curved iron plate.

The dispensing chute 10 can be suspended to a loading device along with a trunnion 18 that is integrally formed with the upstream portion 14 and located outside of its inlet 20. The inlet 20 is assembled into a (circumferentially closed) tubular passage portion. An end opposite the inlet of the upstream portion 14 is assembled such that the downstream member is fixed to one of the coupling portions. The upstream and downstream portions 14, 16 define a passage 22 therein, through which the bulk material entering the distribution chute 10 via the inlet 20 is delivered to the outlet 24, and the material is then discharged from the outlet 24. For example, it is entering the loading area of a blast furnace.

Figure 2 shows a blast furnace charging unit equipped with the dispensing chute of Figure 1. The dispensing chute 10 is pivotally suspended with its trunnion 18 to a rotatable structure 25. The rotatable structure 25 is rotatably supported in a fixed housing 30 by a large diameter ball bearing 32. The inner race of the ball bearing 32 is fixed to a top end flange 34 of the rotatable structure 25, and the outer race of the ball bearing 32 is fixed to one of the top plates 36 of the fixed housing 30. The ball bearings 32 are assembled such that the rotatable structure 25 and the dispensing chute 10 are rotatable about the generally vertical axis 38, which axis generally coincides with the central axis of the blast furnace. A central feed port 26 is centered at the axis 38 and defines a passage for bulk material to pass through the top plate 36. By rotating the dispensing chute 10 about the axis 38, and by varying the pivoting angle of the dispensing chute 10 about the pivot axis 39, the loading device of Figure 2 achieves the loading of the loading material in the blast furnace. Distribution in the district. The pivot axis 39 is generally perpendicular to the axis 38. Details of the mechanism suitable for rotating and pivoting the dispensing chute 10 are not shown in the drawings and are not further described herein. For those interested in such institutions, for example, reference is made to US 3,880,302.

When bulk material (e.g., coke, ore, granules, etc.) is supplied to the distribution chute 10 through the feed port 26, it strikes the bottom of the passage 22. The impact position is determined according to the inclination angle of the distribution chute 10. In order to have a high discharge angle (which is here between the velocity vector of the bulk material at the outlet 24 of the distribution chute 10 and the vertical axis 38), the bulk material impinges on the inlet 20 On the bottom of the channel. By reducing the discharge angle, the impact position is removed from the inlet 20 toward the outlet 24 of the chute 10. The passage 22 has a bend 28 in the upstream portion 14 for gradually deflecting material striking the bottom of the passage in the inlet 20 from a direction perpendicular to the discharge direction. The material impinging on the bottom of the passage in the inlet 20 is first diverted into a first flow direction generally parallel to the bottom of the inlet. At the bend 28, the material is then diverted into a second flow direction parallel to the bottom of the outlet 24. The bend 28 defines an angle a between 20° and 40° between the bottom of the passage of the inlet and the bottom of the passage of the outlet.

The downstream portion 16 and the upstream portion 14 are fixed to each other at the coupling portion 40 of the upstream portion 14. The coupling portion 40 is disposed at the opposite end of the inlet 20 for the bent portion 28. The upper end portion of the downstream portion 16 is inserted into the coupling portion 40 up to the bent portion 28 and is fixed in this position. In the illustrated example, the length of the overlapping portion of the coupling portion 40 and the downstream portion 16 amounts to about one-third of the overall length of the downstream portion 16.

As best illustrated in Figures 2 and 3, the dispensing chute 10 includes a first insert 42 and a second insert 44, the first insert 42 being defined in the upstream portion 14. The holding chambers define a plurality of holding chambers in the downstream portion 16. The holding chambers are opened to the passage so as to be able to fill the bulk material and thus protect the dispensing chute against wear. The inserts are disposed in areas that are most susceptible to erosion by the impacted bulk material. Each of the inserts 42, 44 includes a plurality of transverse plates 46 that tend to be generally opposite the flow of the bulk material. One or more longitudinal plates 48 divide the holding chambers laterally of the channel to ensure a more uniform filling of the holding chambers in the lateral regions of the chute 10. Further details of the various possible configurations of the holding chambers can be found, for example, in EP 0 640 539.

The outlet 24 of the distribution chute 10 is formed by an anti-wear sliding insert 50 disposed in the downstream portion 16. The sliding insert 50 forms a substantially smooth and slightly tapered passage portion in the outlet as compared to the regions in which the plurality of retaining chambers are disposed, so as to discharge a bulk material that is as concentrated and uniform as possible. flow. The surface formed by the sliding insert is substantially aligned with the top edge of the transverse plates 46 and the downstream of the longitudinal plates of the bends 28. The slope of the outlet determines the discharge angle β which can be varied by about 10° (central loading position) and about 50° by pivoting the chute about the pivot axis 39.

The chute body 12 has an opening 52 on the inside of the bent portion 28. In the vertical cross-sectional view of FIG. 2, it is seen that the opening 52 is configured to define a recess that allows the angle of inclination of the chute 10 to be increased without contacting the bottom end of the rotatable structure 25. The radially inner edge 54 of the flange. Another advantage of the opening 52 is that in the "central loading" position, the bulk material can fall straight through the chute 10 without being caused by the top of the passage 22 in the bend The deflection of the folds 28. In addition, the opening can even serve as an overflow in some cases.

In the illustrated distribution chute, the bent portion in the upstream member corresponds to a sharp transition region between each substantially straight channel portion. Those skilled in the art will appreciate that the bend can also be implemented as a smoothly curved transition region between the inlet and the bottom of the channels in the outlet.

Although a particular embodiment has been described in detail, it will be appreciated by those of ordinary skill in the art Therefore, the particular configurations disclosed are for illustrative purposes only and are not intended to limit the scope of the invention. The scope of the invention is intended to be Given.

10. . . Distribution chute

12. . . Chute body

14. . . Upstream part

16. . . Downstream part

18. . . Operating trunnion

20‧‧‧ entrance

22‧‧‧ channel

24‧‧‧Export

25‧‧‧Rotatable structure

26‧‧‧Feed

28‧‧‧Bending

30‧‧‧Fixed housing

32‧‧‧Ball bearings

34‧‧‧Top flange

36‧‧‧ top board

38‧‧‧vertical axis

39‧‧‧ pivot axis

40‧‧‧Connected section

42‧‧‧First insert with multiple holding chambers

44‧‧‧Second insert with multiple holding chambers

46‧‧‧horizontal board

48‧‧‧ longitudinal board

50‧‧‧Sliding inserts

52‧‧‧ openings

54‧‧‧Edge of the bottom flange

1 is a perspective view showing a distribution chute according to a preferred embodiment of the present invention;

Figure 2 is a vertical sectional view of a loading device equipped with a dispensing chute according to one of Figure 1;

3 is a top plan view of the distribution chute of FIG. 1.

10. . . Distribution chute

12. . . Chute body

14. . . Upstream part

16. . . Downstream part

20. . . Entrance

twenty two. . . aisle

twenty four. . . Export

25. . . Rotatable structure

26. . . Feed port

28. . . Bending section

30. . . Fixed housing

32. . . Ball bearing

34. . . Tip flange

36. . . roof

38. . . Vertical axis

39. . . Pivot axis

40. . . Connection part

42. . . First insert with multiple holding chambers

44. . . Second insert with multiple holding chambers

46. . . Horizontal plate

48. . . Vertical plate

50. . . Sliding insert

52. . . Opening

54. . . Edge of the bottom flange

Claims (14)

A dispensing chute (10) for a bulk material dispensing device, in particular for a filling material dispensing device for a metallurgical reactor such as a blast furnace, the dispensing chute comprising: a channel (22) a chute body (12) having an inlet (20) for receiving a flow of bulk material, and an outlet (24) for discharging the bulk material, the passage (22) for Bulk material is transported from the inlet (20) to the outlet (24), the passage (22) having a bend (28) to divert the flow from a first flow direction in the inlet (20) to a a second flow direction in the outlet (24), characterized in that the chute body (12) is combined with at least one upstream portion (14) and a downstream portion (16), the upstream portion (14) including the The inlet (20), and the downstream portion (16) includes the outlet (24), the downstream portion (16) defining a straight portion of the passage (22), and the upstream portion (14) defining the inlet (20) And the bent portion (28) of the passage (22), and characterized in that the upstream portion (14) is thick-walled relative to the downstream portion (16), the upstream portion (14) a coupling end (40) opposite the inlet (20) for the bent portion (28), wherein the downstream portion (16) is inserted into the coupling end portion (40), preferably The bent portion (28) is reached and fixed to the upstream portion (14). The distribution chute (10) of claim 1, wherein the upstream portion (14) is made of cast metal, preferably cast iron or cast steel. The distribution chute (10) of claim 2, wherein the downstream portion (16) comprises one or more welded curved steel plates. The distribution chute (10) of any one of claims 1 to 3, wherein the inlet (20) is provided as an annular collar on the upstream portion (14). The dispensing chute (10) of any of claims 1 to 3, wherein the downstream portion (16) comprises a tubular section provided with the outlet (24). The distribution chute (10) according to any one of claims 1 to 3, wherein the downstream portion (16) gradually merges from a joint portion to which the upstream portion (14) is attached toward the outlet (24) Thinning. The distribution chute (10) of any one of claims 1 to 3, wherein the passage (22) has a first passage axis in the inlet (20) and a outlet (24) a second channel axis, and wherein the bend (28) in the upstream portion defines an angle between the first and second channel axes, the angle preferably being between 15° The range of 45° is more preferably in the range of 20° to 40°. The distribution chute (10) of claim 7, wherein the bend (28) in the upstream portion (14) defines a bend between the first and second passage axes Transition zone. The distribution chute (10) according to any one of claims 1 to 3, wherein the length of the overlapping portion of the coupling end portion (40) and the downstream portion (16) amounts to the downstream portion (16) ) 20% to 40% of the overall length. A dispensing chute (10) according to any one of claims 1 to 3, comprising an insert (42, 44) in the upstream portion (14) and/or the downstream portion (16) The insert (42, 44) includes retention chambers, The holding chamber is opened to the passage (22) so as to be able to fill the bulk material used to protect the dispensing chute against wear. The distribution chute (10) of any one of claims 1 to 3, wherein the chute body (12) includes an anti-wear sliding insert (50) in the interior of the downstream portion (16) The anti-wear sliding insert (50) forms an outlet (24). The distribution chute (10) of any one of claims 1 to 3, wherein the chute body (12) has an opening (52) on an inner side of the bent portion (28). A dispensing chute (10) according to any one of claims 1 to 3, comprising an operating trunnion (18) on the upstream portion (14), the operating trunnions (18) Preferably, it is integrally formed with the upstream portion (14). A metallurgical reactor, such as a blast furnace, comprising a charging device with a filling material dispensing device, the filling material dispensing device being equipped with a dispensing chute as claimed in any one of claims 1 to 13. (10).