RU2205701C1 - Magnetic separator - Google Patents

Abstract

FIELD: devices for removal of inclusions at size of 0.1 mcm and greater both from liquid and loose materials; food- processing, light, chemical, pharmaceutical and other industries; construction engineering; flour and baking industries. SUBSTANCE: magnetic separator has at least one working member which is secured on flange; it includes circular permanent magnets arranged in series with similar poles directed towards each other; they are secured on rod and are enclosed in cartridge tight for products being cleaned. Thickness of ring of distance insert is equal to 0.1-0.8 of thickness of permanent magnet ring; number of pairs of rings: permanent magnet - distance insert ranges from 100 to 200 per meter of length of working member. Permanent magnets are made from solid alloy at high magnetic energy, for example, Nd FeB or Sm Co5. Thickness of wall is 0.3-1 mm. EFFECT: enhanced efficiency of separation. 7 cl, 2 dwg

Description

 The invention relates to a device for removing magnetic inclusions with a particle size of 0.1 microns or more, both from bulk and from liquid materials in the food, light, chemical, construction, pharmaceutical and other industries. Such devices are especially widely used in the milling and baking industries.

 A known electromagnetic separator, comprising an electromagnet with pole tips, between which is located the product pipeline with polygradient elements rigidly fixed on its inner side surface, and magnetic field induction concentrators in the form of rods. The latter are fixed on the horizontal axes. When voltage is applied to the magnetization coils in the interpolar space, an uneven magnetic field is created and the free ends of the concentrators rotate under its action and occupy a position along its lines of force (RU, patent, 2012418, B 03 С 1/26, 05.15.94).

 The proposed design ensures the operation of the separator when passing through the product pipeline oversized separated particles, but is not effective in the separation of fine particles.

 The presence of an electromagnet complicates operation, increases the dimensions, weight and cost of installation. In addition, such installations impose increased requirements for compliance with safety conditions.

 Known magnetic separator for cleaning from ferromagnetic impurities of mercury in the stream, containing a working element of a ring of sequentially placed permanent magnets and distance inserts mounted on a rod and enclosed in a non-magnetic cartridge impervious to cleaned products. Permanent magnets are located in relation to each other with the same poles and their thickness is equal to the height of the distance inserts. In this case, the permanent magnets and the distance inserts are separated by elastic gaskets. And the cartridge is equipped with a removable outer frame made of ferromagnetic soft magnetic material, made in the form of a set of longitudinal plates fixed between the upper and lower fixing elements (USSR, copyright certificate 682579, B 03 С 1/26, 08/30/07.

 However, such a device does not provide effective interaction of finely divided ferromagnetic particles with a magnetic field in a viscous medium. In addition, it is quite bulky and difficult to manufacture.

 The present invention solves the problem of creating a small-sized, high-performance and easy to use, effective magnetic separator, so necessary in modern production for the reliable removal of the smallest ferromagnetic impurities.

 The problem is solved in that in the known magnetic separator containing at least one working element of ring sequentially placed permanent magnets located relative to each other by the same poles, and remote inserts mounted on a rod and enclosed in impervious to cleaned products a cartridge made of non-magnetic material, new is that, the permanent magnets are made of hard alloy with high magnetic energy, the thickness of the ring of the remote insert is 0.1-0.8 Thickness of the permanent magnet rings, and the number of pairs of rings: permanent magnet insertion distance is 100-200 per 1 meter length of the operating member.

Performing linear dimensions within the specified limits provides high values of not only the magnetic field, but also the magnetic field gradient, and hence the attractive force in the direction of movement of the ferromagnetic particle towards the poles, together with a high bulk density of the poles in the space of the separator where the product to be cleaned is located. The proposed design makes it possible to achieve a high density of magnetic poles with high magnetic field inhomogeneity, which significantly increases the separation efficiency, since a force directed to the pole of the magnet:
F = κVH dH / dX,
where κ is the specific susceptibility of a ferromagnetic particle;
V is the particle volume;
H is the magnitude of the inhomogeneous magnetic field;
dH / dX is the magnetic field gradient along the direction of movement of the ferromagnetic trapped particle.

 Permanent magnets are best made from NdFeB alloy (the cheapest option).

 They can also be made of SmCo5 alloy.

 The separator works most efficiently with a cartridge wall thickness of 0.3-1 mm.

 The working elements can be fixed on the flange in a row planarly (in one plane), while the optimal distance between adjacent elements is equal to the diameter of the working element.

 The working elements can be fixed on the flange in several rows in parallel planes in a checkerboard pattern, and with the formation of a cylindrical surface.

 The rod and the cartridge are made of non-ferromagnetic material, for example, austenitic stainless steel or duralumin. Remote inserts can be made of both non-magnetic and magnetic material.

 In FIG. 1 is a front view of the proposed separator, figure 2 is a top view with highlighting the horizontal section of one of the elements.

 The magnetic separator contains mounted on a flange 1 located in a row in the same plane of the working elements 2. Each of them consists of a ring of sequentially placed permanent magnets 3, located relative to each other by the same poles, and remote inserts 4, mounted on the rod 5 and enclosed in impervious to cleaned products cartridge 6. The thickness of the ring of the remote insert 4 is 0.2 the thickness of the ring of a permanent magnet 3.

 Magnetic separator operates as follows. Flange 1 with working elements 2 fixed on it is placed in a sifter of bulk materials, for example, under a sieve in a sifting chamber of a flour sifter, or in a liquid to be cleaned.

 Ferromagnetic impurities form precipitates in the form of rings on the outer cartridge 6 in places corresponding to the poles of the magnets, i.e. in a zone with high magnetic field inhomogeneity. Periodically, the magnetic separator is removed from the cleaning zone and the adhering ferromagnetic impurities are removed from the cartridges by a clean cloth 6. In the manufacture of NdFeB magnets and the use of a magnetic separator to clean the flour, the latter was cleaned of metal impurities with a particle size of 0.1 microns or more.

Claims (7)

 1. A magnetic separator containing at least one working element of annular sequentially placed permanent magnets located relative to each other by the same poles, and remote inserts mounted on a rod and enclosed in a non-magnetic cartridge impervious to cleaned products, characterized the fact that the permanent magnets are made of a hard alloy with high magnetic energy, the thickness of the ring of the remote insert is 0.1-0.8 the thickness of the ring of the permanent magnet, and the number of pairs of EC: Permanent magnet - the remote insert is 100-200 per 1 m of the length of the working element.  2. The magnetic separator according to claim 1, characterized in that the permanent magnets are made of an NdFeB alloy.  3. The magnetic separator according to claim 1, characterized in that the permanent magnets are made of SmCo5 alloy.  4. The magnetic separator according to claim 1, characterized in that the wall thickness of the cartridge is 0.3-1 mm  5. The magnetic separator according to claim 1, characterized in that the working elements are mounted on the flange in a row planarly, and the distance between adjacent elements is equal to the diameter of the working element.  6. The magnetic separator according to claim 1 or 4, characterized in that the working elements are mounted on the flange in several rows in parallel planes in a checkerboard pattern.  7. The magnetic separator according to claim 1, characterized in that the working elements are fixed on the flange with the formation of a cylindrical surface.

Images