Magnetic matrix for high intensity magnetic separator

Abstract

The invention relates to a magnetic matrix for high intensity magnetic separator which is fed with a pulp containing magnetic and non-magnetic particles, the magnetic matrix (8) comprising a series of grooved metal plates (7) on both sides thereof, the grooved plates being arranged in rows parallel to and spaced apart from each other from the same spacing (6) within a housing, each face of each metal grooved plate (7) having the ridges aligned with the valleys of the face facing it of the grooved plate (7), and a corrugated expanded sheet (12) is disposed at each spacing (6) between adjacent grooved plates (7), with corrugations of the corrugated expanded sheets (12) accompanying the ridge-valley alignments of the respective grooved plates (7).

Claims

1. A magnetic matrix for high intensity magnetic separator which is fed with a pulp containing magnetic and non-magnetic particles, the magnetic matrix comprising: a series of metal plates grooved on their two faces, the grooved plates being arranged in a row, parallel to and spaced apart from each other from the same spacing within a housing, wherein each face of each grooved metal plate has the ridges aligned with the valleys of the face facing it of the adjacent grooved metal plate; and a corrugated expanded sheet disposed in the spacing between adjacent grooved plates with the corrugations of the corrugated expanded sheets corresponding to the ridge-valley alignments of the respective adjacent grooved plates.

2. The magnetic matrix for high intensity magnetic separator according to claim 1, wherein one of the corrugated expanded sheets has a different height than another one of the corrugated expanded sheets, and the height of each of the corrugated expanded sheets is less than or equal to the height of the grooved plates.

3. The magnetic matrix for high intensity magnetic separator according to claim 2, wherein the height of each corrugated expanded sheet is selected as a function of at least one of a hydraulic load of the pulp, a flow speed of the pulp, and a residence time of the pulp within the matrix.

4. The magnetic matrix for high intensity magnetic separator according to claim 1, wherein each corrugated expanded sheet has a handle on its upper end.

5. The magnetic matrix for high intensity magnetic separator according to claim 2, wherein each corrugated expanded sheet has a handle on its upper end.

6. The magnetic matrix for high intensity magnetic separator according to claim 3, wherein each corrugated expanded sheet has a handle on its upper end.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The drawings attached hereto illustrate:

(2) FIG. 1—a front view of a magnetic matrix according to the state of the art, using ridge-to-ridge aligned grooved plates;

(3) FIG. 1A—an enlarged detail view of a magnetic matrix of FIG. 1;

(4) FIG. 1B—an enlarged detail view of the magnetic matrix of FIG. 1 with a flattened expanded sheet disposed between the plates;

(5) FIG. 2—a magnetic matrix according to the present invention;

(6) FIG. 2A—an enlarged detail view of a magnetic matrix of FIG. 2;

(7) FIG. 2B—an enlarged detail view of the magnetic matrix of FIG. 2 with a flattened expanded sheet disposed between the plates;

(8) FIG. 3—a perspective view of the magnetic matrix according to the present invention;

(9) FIG. 3A—an enlarged detail view of a magnetic matrix of FIG. 3, without a portion of the outer housing of the matrix, and showing its interior;

(10) FIG. 3B—an enlarged detail view of the grooved plates with corrugated web plate grooves within the matrix of FIG. 3;

(11) FIG. 4—a view of the magnetic matrix with cuts in varying planes, showing the arrangement of the grooved plates and the corrugated web plates;

(12) FIG. 5—a detail view of the corrugated expanded web plate in front of the grooved plate.

DETAILED DESCRIPTION OF THE DRAWINGS

(13) This invention may be better understood through FIGS. 1 to 5. FIG. 1 shows a conventional magnetic matrix 1, which is the current market standard, and which can best be seen in detail from FIG. 1A. In magnetic matrices of high intensity magnetic separators (WHIMS), the grooved plates 7 are arranged with the ridges of adjacent plates perfectly aligned along line 3. The spacing 6 between the grooved plates 7 is indicated by the distance indicated by reference 6 existing between the ridges of the adjacent grooved plates 7. This spacing 6 is named simply as “GAP” in magnetic separation technology.

(14) FIG. 1B shows in enlarged detail a version of the magnetic matrix with flattened expanded sheet 5 arranged between the grooved plates. It is noted that the ridge-ridge alignment of the grooved plates does not allow sufficient space between two grooved plates to engage a corrugated sheet therebetween, which completely fills the grooves of the plates.

(15) FIG. 2 shows a magnetic matrix 8 according to the present invention constructed with grooved plates 7, which can be seen more clearly in the detail of FIG. 2A. Line 10 indicates the alignment of the ridge of a plate with the valley of the adjacent plate, characterizing the ridge-valley configuration. This type of assembly of the grooved plates 7 allows the insertion between two adjacent plates of a corrugated expanded sheet 12, preferably of steel, which efficiently fills the space of the grooves, as shown in the enlarged detail view 2B.

(16) Comparing FIG. 1B with FIG. 2B, it can be seen that the corrugated expanded sheet 12 has a total extent up to 41% greater than the length extension of the flattened expanded sheet 5. This increase in length can be confirmed by the fact that the overall width of the corrugated expanded sheet 12 is formed by the sum of the sides of the isosceles rectangular triangles that enter the grooves one by one while the length of the flat expanded sheet is equal to the sum of the bases of these triangles. The geometric relationship indicates that the sum of the sides of these triangles is 1.41 times the length of the bases.

(17) This configuration of the corrugated expanded steel sheet 12 which allows this increase in length is one of the main factors to increase the production of the corrugated magnetic matrix, since this increase in length directly results in the increase of the collecting surface of the magnetic microparticles.

(18) FIG. 3 shows a perspective view of the magnetic matrix 8 according to the present invention with the grooved plates 7 in the ridge-valley arrangement and the corrugated sheets 12 disposed therebetween. That embodiment of the invention which is most clearly illustrated in the enlarged detail views of FIG. 3A, showing the matrix without a portion of its outer housing for viewing the plates and sheets therein, and FIG. 3B shows in detail the interior of the matrix. The corrugated sheets consist of a number of corrugated or zigzag threads 16 forming a corrugated expanded web. Such corrugated webs 12 have, at their corners, collecting edges 17 which are also responsible for the generation of the magnetic gradient responsible for the attraction of the magnetic microparticles. Such corrugated web sheets 12 are also inserted between the grooved plates.

(19) As can be seen in FIG. 3, for handling the corrugated expanded sheets 12, handles 15 are available at their upper ends, through which the corrugated sheets 12 can be moved up and down both at the times of installation and removal of the corrugated sheets 12, as in the cleaning moments of the grooved plates.

(20) FIG. 4 depicts a cross-sectional view of the magnetic matrix 8 with the ridge-valley configuration shown in cross-section in varying planes, so that the corrugated sheets 12 with variable heights can be viewed, with a higher height 19 and a lower height 20. The flow of pulp being fed is represented by arrow 18. By choosing the appropriate height of the corrugated expanded sheet 12, it is possible to adjust the hydraulic pressure loss to define the pulp flow rate, and also to correctly adjust the residence time of the pulp within the separator matrices to the specific characteristics of the mineral being processed.

(21) FIG. 5 shows the corrugated expanded sheet 12 in front of the grooved plate 7. Some collecting edges 17 highlighted in bold 21 indicate the length of the lines where the magnetic particles are collected in order to better clarify the effect that the increased length of the corrugated expanded sheet has on increasing production.

(22) The modifications described herein applied to this type of corrugated magnetic matrix also provide three features that improve the magnetic separation process, namely:

(23) 1. The presence of the sheet between the matrices allows to reduce the rate of the separating pulp, reducing, therefore, the hydrodynamic drag that the contained water exerts on the microparticles. Reduced rate is a key factor so that the microparticles have sufficient time to be collected at the edges formed by the corrugated expanded sheet fillets.

(24) 2. The corrugated shape and the multiplicity of edges of the corrugated expanded sheet allows for a substantial increase in the collection points of the microparticles, enhancing the bulk recovery of the salable product. This prolongation of the fillet collecting edges together with the pulp speed reduction and the generation of high magnetic gradients add up to maximize recovery and the quality of the magnetic product.

(25) 3. Since the grooved plates are aligned in the ridge-valley form, and because of the corrugated shape of the expanded sheets which are inserted between the channels formed by the opposed grooved plates, being intermeshed therebetween, that arrangement forms a sandwich, allowing, in case of clogging of the channels for any reason, the rapid elimination of obstruction simply by removing these corrugated steel screens from within the matrix channels.

(26) Removing the screen drags away the materials that are causing the clogging. The removed screen can then be cleaned and easily repositioned in the original position, thus completing the unclogging process. In this way, there is no need to use other cleaning equipment for the small space between the grooved plates, since these corrugated expanded sheets serve as a natural tool to clean the grooves in case of clogging.

(27) In addition, this corrugated magnetic matrix has such a structure that, when subjected to the field of the magnetic separator, enables one to obtain by induction magnetic inductions within the range of up to 18,000 Gauss with magnetic gradients up to 4000 Gauss/mm, significantly increasing its ability to extract ultrafine particles from the ore being processed. This is because corrugated expanded sheets contribute to increase the value of the magnetic field within the matrix.

(28) The combined operation of all of these described features add together to provide the high performance, productivity and ease of operation of the corrugated magnetic matrix object of this invention.

(29) The example described above represents a preferred embodiment; however, it should be understood that the scope of the present invention encompasses other possible variations, and is limited only by the content of the appended claims, which include all possible equivalents.