SU1666220A1 - Screening apparatus - Google Patents

Abstract

The invention relates to the enrichment of minerals and is intended for the hydraulic screening of materials in the coal, mining and metallurgical, and other industries. The goal is to improve the quality of separation products during hydraulic screening. The device contains at least one section 1 of the screening surface (PP) with longitudinal grate 2 installed on cross-links 3. At the same time, cross-links 3 are set relative to PP with a slope decreasing and a gap increasing to the unloading end of the device. -v Facing the ends of the device end of the grate 2 sections 1 m. inclined toward the PP at an obtuse angle and shifted in plan by half a step relative to the ends of the grate 2 of the previous section 1. The device allows for faster removal of dense pulp into the undersize product by reducing the flow resistance due to a reduction in the area of the obstacle. Due to the inclination and shift of the ends of the grates 2 of the adjacent sections 1, the outflow of the liquid phase in the PP slot is additionally delayed. This helps to increase the length L of the saturated region. 1 hp ff, 7 ill.

Description

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The invention relates to the enrichment of minerals, in particular to devices for the hydraulic screening of materials, and can be used in the coal, mining and smelting and other industries.

The purpose of the invention is to improve the quality of separation products during hydraulic screening.

Figure 1 shows a screening device, longitudinal section; figure 2 - section aa in figure 1 (cross-section of the boot area I); in FIG. 3 a section B-5 in FIG. I {cross section), in FIG. 4 is a view of In figure 1 (top view); Figure 5 is a fragment of the device, top view (example of embodiment); Fig. 6b is a section of the G-D of Fig. 5 (longitudinal section of the section junction assembly); Fig. 7 is a diagram of pulp flow along a section length.

The screening device (Fig. 1) contains a screening surface made in the form of sections 1, each of which consists of grates 2 and cross links 3 made in the form of combs with grooves 4.

Grid-irons 2 are oriented along the longitudinal axis OX of the device and are located with a step t in the grooves of 4 dies. Sections 1 are fixed at an angle to the horizon of 40-55 ° in a stationary housing 5 with a loading nozzle b, discharge nozzles and 8 and a device 9 for supplying water. Unlike the prototype, the cross link 3 of each section facing the boot nozzle 6 is inclined to the screening surface (HOU plane) at an ogmax angle of 90 °, and the cross link 3 facing the discharge nozzles is inclined at an angle of 90 min 90 °. Moreover, the connections are established relative to the screening surface with a gap d increasing in the direction of movement of the material to the discharge end of the device.

In the device (FIGS. 5 and 6), the end faces 10 of the grate 2 (section 1) facing the loading nozzle 6 can be inclined to the screening surface at an angle of / 90 ° and shifted in plan by half a step t relative to the grates of the adjacent previous section 1.c

The device works as follows.

The source material in the form of a water-saturated pulp flows from nozzle 6 to the loading section 1 of the section and under the action of gravitational forces and hydrodynamic pressure moves at a speed V along the length L of the device. Due to the high content of the liquid phase in section 1 of length i, small fractions smaller than the size d of the screening surface slit freely pass through the screening

surface into the undersize product.

As the material moves beyond the cnei of a more intensive outflow in the boat phase slit, the material is dehydrated, the pulp density increases.

(the value of T: W increases), which worsens the conditions of classification, since small particles are pelletized and sticking to the grate. For water saturation of the dehydrated pulp along the length L of the device, water supply devices 9 are installed. At the same time, the velocity V of the outflow of the liquid phase and, accordingly, the length of the section 1 of the water-saturated pulp depends on its resistance to movement of the transverse strut 3, which for the moving stream serves as an obstacle

By tilting the transverse link 3 at an angle of a90 ° and installing it with a minimum clearance of 5 minutes, the condition is improved.

to trap the liquid phase on the screening surface.

When a stream encounters with link 3, it is partially reflected upwards, with a return it appears vertical ;.

the (transverse) component of the velocity is Viz, which, firstly, reduces the average. • the velocity Vi of the outflow of the liquid phase in the slot of the screening surface and, secondly, increases the flow turbulization on a section of length i. This contributes to the water saturation of the pulp and the floating upwards due to the vortex displacements of large particles from the lower layers of the flow, as well as the destruction of the pelletized small particles.

Setting the cross-connection 3 at an angle of 90 ° and with a maximum gap (Zmax provides faster removal of dense pulp into the undersize product by reducing flow resistance,

due to the reduction in the area of the barrier.

When the ends of the 10 grate sections 1 are inclined to the direction of movement (V) of the pulp flow at an angle of / 3 90 ° and their shift in

the half-step plan of the grates of the previous section further delays the outflow of the liquid phase in the slot of the screening surface, which contributes to an increase in the E-saturated length

the site and by reducing the removal of coarse fractions into the undersize product to improve the quality of separation products while reducing the water consumption by the device 9.

Claims (2)

Claim 1. A screening device comprising at least one section of a screening surface with longitudinal grates installed on cross-links, characterized in that, in order to improve the quality of separation products during hydraulic screening, cross-links are installed relative to the screening surface with on a clone decreasing by a clearance increasing to the discharge end of the device. 2. The device according to claim 1, characterized in that the ends of the grid bars of the section facing the loading end of the device are inclined to the screening surface at an obtuse angle and shifted in plan by half a step relative to the ends of the grid bars of the previous section. FIG. 2 .3 x Fy FIG. 7 Editor I. Casarda Compiled by B. Levchaev Tehred M. Morgental Proofreader. Shevkun