RU2843940C2 - Centrifugal jigging machine - Google Patents

Abstract

FIELD: performing operations.

SUBSTANCE: invention relates to dressing of minerals and can be used for dressing of gold-bearing stock, other ores and sands containing platinum group metals in grain size of -8+0 mm. Centrifugal jigging machine includes a support frame, a jigging compartment, a jigging chamber, a device for creating ascending-descending water pulses in the jigging compartment, loading device for supply of initial feed, unloading device for upper and lower product, device for supply of oversize water and unit for supply of undersize water. Oversize water supply device is made in the jigging chamber and represents at least two branch pipes directed in series in one direction, which longitudinal axis is directed tangentially to the jigging chamber central axis with possibility of the oversize water supply at a tangent to the jigging chamber inner wall. Initial feed appliance is composed of loading tray made up of disc fixed at settling chamber centre above top product discharge appliance with clearance.

EFFECT: creation of uniform centrifugal field along the whole circumference of settling chamber facilitating more efficient separation of material.

2 cl, 12 dwg

Description

The invention relates to the field of mineral enrichment and can be used for enrichment of gold-containing raw materials, other ores and sands containing platinum group metals in the size range of -8+0 mm.

There are known serially produced jigging machines of the OMGR type (www.tokltd.com), MOD type (www.zavodtrud.ru), MO type (www.zaoplatov.ru), which are used in the gold mining industry both in Russia and abroad.

The enrichment of raw materials occurs due to one physical effect - ascending-descending pulses of water. The disadvantage of these machines is the decrease in the efficiency of enrichment with a decrease in the size of the processed material less than 2.0 mm.

The Centrifugal Jigging Machine (Patent of the Russian Federation 2209679, 2001) is known from the field of technology. In this case, two physical processes are combined: separation of the material by density due to the effect of ascending-descending water pulses and due to the effect of the centrifugal force arising from the rotation of the jigging chamber. The disadvantage of this machine is the relative complexity of the design and the limited size of the feed.

The closest analogue (prototype) to the proposed invention in terms of the physical essence of the separation process carried out is a centrifugal jigging machine, including: a support frame, two cylindrical jigging compartments with a conical lower part, two jigging chambers having a loading device in the form of a tangentially executed input trough for introducing the initial feed and oversize water, a device for creating ascending-descending pulses of water in the jigging compartments, unloading devices for the upper and lower products (Patent RU 2737044 2019).

In this case, the separation of the enriched raw material occurs due to two physical effects: centrifugal force and jigging in ascending-descending pulses of water.

The disadvantages of the prototype include the insufficient effect of centrifugal force along the entire circumference of the jigging chamber (which is directly stated in the Description of the Invention to the Patent, p. 8, paragraph 25) and local abrasive wear of the wall of the jigging chamber in the zone of the input of the initial feed, where the velocity pressure of the oversize water is maximum. These factors are due to the combined process of feeding the initial feed and oversize water into the input trough of the jigging chamber.

The invention is based on the idea of creating a continuous centrifugal field around the entire circumference of the jigging chamber.

The stated objective is achieved by the fact that the centrifugal jigging machine, which includes: a support frame, two symmetrically located jigging sections, a device for creating ascending-descending pulses of water in the jigging sections, a loading device for the initial feed and an unloading device for the upper (tails) product and the lower (concentrate) undersize product, a device for feeding oversize water and a unit for feeding undersize water, has the following features that affect the technical result:

Separation department is a cylinder open at the top.

Device for creating ascending-descending water pulses It consists of an electric drive, a crank mechanism, a balance frame with movable cones installed on it and rubber diaphragms connected to the jigging sections.

Jigging chamber It is an open-topped cylinder with a sieve installed at the bottom. A stainless steel sieve with a 0.5 mm gap is used as a sieve. There is an opening in the center of the sieve for installing a tailings unloading device. The jigging chamber is fixedly installed on the jigging section from above. The rotation of the jigging chamber is not provided.

Loading device is a receiving bin with outgoing chutes that allow the initial feed to be introduced into the zone of action of the maximum centrifugal force created along the periphery of the jigging chamber. In a particular case, the loading device can be made in the form of a receiving bin and a loading tray , which allows the initial feed to be evenly distributed over the entire circumference of the jigging chamber. In another particular case, when the initial feed is supplied by a hydrocyclone, the loading device may be absent.

Unloading device the top product is tail pipe , installed vertically in the center of the jigging section. In the upper part, the tail pipe has a through outlet into the jigging chamber through an opening in the sieve. The upper end part of the tail pipe is located at a certain height from the sieve, determined by the height of the layer of enriched material. The lower part of the tail pipe is led outward, beyond the under-sieve space of the jigging section. In the lower part of the tail pipe there is a device for unloading the bottom sub-screen product The tail pipe and the device for unloading the lower undersize product are made as a single unit.

Over-sieve water supply device is a set of nozzles (nozzles) cut into the jigging chamber tangentially. The number of nozzles is determined by the diameter of the jigging chamber to create a continuous "water ring". On the outside of the jigging chamber, the nozzles are enclosed in a single toroidal body of rectangular cross-section for uniform pressure distribution and general water supply. The device for feeding over-sieve water and the jigging chamber are made as a single unit.

Under-grate water supply unit is a branch pipe with the ability to supply water to the under-sieve space of the jigging section.

The declared centrifugal jigging machine differs from the prototype in that the over-sieve water is fed into the jigging chamber tangentially, through pipes located sequentially along the entire circumference, one after another. In this case, the forming "water ring" creates a continuous centrifugal field.

The declared new distinctive feature allows to obtain an effective centrifugal field along the entire circumference of the jigging chamber.

The given distinctive feature is not known and does not obviously follow from the state of the art.

Fig. 1, 2 shows a general view of the claimed centrifugal jigging machine with a loading device in the form of a receiving bin and outgoing chutes.

Fig. 3 shows a diagram of a centrifugal jigging machine, a top view and a longitudinal section, when working with a loading device in the form of a receiving bin and outgoing chutes. The diagram of the feed supply, unloading of the lower undersize product and tailings, and the supply of oversize and undersize water are shown.

Fig. 4 shows a general view of the claimed centrifugal jigging machine with a loading device in the form of a receiving bin and a loading pallet.

Fig. 5 shows the design of the loading pallet.

Fig. 6 shows a diagram of a centrifugal jigging machine, a top view and a longitudinal section, when working with a loading device in the form of a receiving bin and a loading tray. The diagram of the feed supply, unloading of the lower undersize product and tailings, and the supply of oversize and undersize water are shown.

Fig. 7 shows a general view of the claimed centrifugal jigging machine with the initial feed supplied by hydrocyclones.

Fig. 8 shows a diagram of a centrifugal jigging machine with hydrocyclones, without the use of a loading device.

Fig. 9 shows a diagram of the supply of over-sieve water to the jigging chambers through pipes (nozzles) located in the toroidal body.

Fig. 10 shows a device for unloading the lower undersize product.

Fig. 11 shows the design of the device for unloading the lower sub-sieve product in section.

Fig. 12 shows a centrifugal jigging machine – prototype.

The claimed centrifugal jigging machine includes: a support frame (1) on which two identical, symmetrically located jigging sections (2) are located, each of which contains a jigging chamber (3) with a sieve (4) installed in its lower part and a loading device (5), a tail pipe (6), a sub-sieve water supply unit (7) and a device for supplying over-sieve water (8), a large diaphragm (9) and a small diaphragm (10) determining the mobility of a cone (11) installed on a balance frame (12). The centrifugal jigging machine also includes a device for unloading the lower sub-sieve product (13), a drive providing reciprocating movements of the balance frame (not shown in Fig. 1).

The declared centrifugal jigging machine operates as follows.

Loading the original power supply. The loading of the initial feed must be provided in such a way that the material enters the jigging chamber as close as possible to its wall, where the centrifugal force is maximum. There are two methods of loading a centrifugal jigging machine: conventionally "dry" and "wet".

The “dry” method involves feeding dehydrated material (for example, after a screening operation or in the form of sand from a hydroclassifier) through inclined chutes, pipelines, etc.

Loading occurs as follows: The initial feed of size -8+0 mm enters the centrifugal jigging machine in two parallel streams, into the receiving bins of the loading device, from where it enters the periphery of the jigging chamber into the centrifugal field via several inclined chutes (pipelines).

There is an alternative method of introducing the initial feed into the centrifugal field - using a loading pan instead of inclined chutes. The loading pan in the form of a disk is installed in the jigging chamber horizontally, at a certain height from the tail pipe, has a diameter slightly smaller than the diameter of the jigging chamber. The loading pan, along the circumference, has sides of 30-50 mm for the initial accumulation of the initial material and protection from wear. The loading pan has four L-shaped tubular posts located diametrically (Fig. 5), which have an important function - ejection of air into the tail pipe. At the same time, the L-shaped posts serve to fix the loading pan in the jigging chamber and are used as handles for its removal and installation. Receiving bins are located in the center of the loading pallets, at a certain height.

Loading is performed as follows: The initial feed of size -8+0 mm is fed to the centrifugal jigging machine in two parallel streams, into the receiving bins of the loading device, from where it is unloaded onto loading pallets. After filling the loading pallets and forming a cone of the initial feed with an angle of natural slope, the material begins to unload by gravity (slide) through the sides of the loading pallet into the jigging chamber along the entire circumference. The distance between the side and the wall of the jigging chamber (gap) should be as small as possible, so that the initial feed enters the zone where the centrifugal force is maximum. At the same time, this distance should not be less than three times the size of the maximum particle size in the initial and feed, to prevent jamming.

The loading tray has another important function – for the safety of the product, since it completely blocks unauthorized access to the concentrate on the sieve.

"Wet" method. In this case, a hydrocyclone is installed above each jigging chamber, in the center. The initial feed is the sand product of the hydrocyclone. As is known, the bottom product of the hydrocyclone is discharged from the sand packing "fan" in the form of a wide open "umbrella". If the "fan" reaches the sides of the jigging chamber, the loading device may not be used, as shown in Fig. 8. If the "fan" does not reach the sides of the jigging chamber, the loading pallet described above is used. The "wet" loading method has an obvious advantage over the "dry" one, since it does not require additional equipment for dewatering the material and lifting it to a height, thereby significantly simplifying the process flow diagram. The use of enrichment short-cone hydrocyclones in combination with a centrifugal jigging machine allows, in some cases, to increase the productivity of the process flow diagram by an order of magnitude. At the same time, a disadvantage is the limited feed size (usually no more than 5 mm), which is determined by the diameter of the sand packing of the hydrocyclone.

Enrichment. The water flow, through the branch pipe (8), enters the toroidal body of the oversize water feed device with installed branches (nozzles). The oversize water enters the jigging chamber tangentially through the nozzles, creating a continuous centrifugal field along the circumference of the jigging chamber. The undersize water, entering through the branch pipe (7), and the reciprocating movements of the cone provide the necessary mobility and separation of the material over the entire area of the jigging chamber. The initial feed, entering from the loading device, is accelerated by the tangential water flow. Under the action of centrifugal force and ascending-descending pulses of water, the material is redistributed by density. The light (upper) product is displaced upward and to the center and goes into the tail pipe (6). The material of intermediate density forms a layer of mineral bed. The material of the lower product (concentrate), with a size of +0.5 mm, continues to move in a circle and accumulates in the lower layer, along the wall of the jigging chamber, gradually filling the entire area of the sieve (4) from the periphery to the center. The technological process is periodically stopped and the concentrate accumulated on the sieve (4) is removed. The material of the lower product -0.5 mm, under the action of ascending-descending water pulses, passes through the sieve (4) and is continuously unloaded through the device for unloading the lower under-sieve product (13).

The claimed invention was implemented by changing the design of the jigging chamber of a centrifugal jigging machine (Fig. 12), which is a prototype and operates as part of the technological line of the SHOU (concentration and processing plant) of an operating gold mining enterprise in the Urals.

Eight nozzles (nozzles) with a diameter of 4 mm were tangentially cut into the circumference of each jigging chamber (diameter/height 340/150 mm). A toroidal body was made to ensure a single supply of over-sieve water.

The tests were carried out on the enrichment of stale tailings from the SHOU, processed several times on the SKO-7.5 concentration table.

The test results confirmed the effectiveness of the changes made.

A continuous centrifugal field in the jigging chamber allowed enriching the material without preliminary classification into narrow classes. Productivity increased twofold when working with a wide size class of -8+0 mm, with an extraction of at least 95%. The changes made allowed to increase the processing volumes and simplify the process flow chart. A decision was made to reprocess all SHOU tailings in order to extract gold, using a centrifugal jigging machine as the main enrichment device, instead of the SKO-7.5 concentration table.

The centrifugal jigging machine claimed for the invention has the following obvious advantages over the prototype:

1. A uniform centrifugal field around the entire circumference of the jigging chamber promotes more efficient separation of the material.

2. Uniform wear of the walls of the jigging chamber increases the service life.

Claims (2)

1. A centrifugal jigging machine comprising a support frame, a jigging section, a jigging chamber, a device designed to create ascending-descending pulses of water in the jigging section, a loading device for feeding the initial feed, an unloading device for the upper and lower product, a device for feeding oversize water and a unit for feeding undersize water, characterized in that the device for feeding oversize water is made in the jigging chamber and is at least two pipes directed sequentially in one direction, the longitudinal axis of which is directed tangentially to the central axis of the jigging chamber with the possibility of feeding oversize water tangentially to the inner wall of the jigging chamber. 2. A centrifugal jigging machine according to paragraph 1, characterized in that the device for feeding the initial feed is made in the form of a loading tray, which is a disk installed motionless in the center of the jigging chamber above the level of the unloading device of the upper product with a gap.