RU1782949C - Process and device for producing granulated slag in rotary drum - Google Patents

Abstract

SUMMARY OF THE INVENTION: the slag melt is poured into a hydrogroove, removed from the hydrogroove with water jets, thermally crushed at a temperature at which maximum stresses arise in the slag, followed by cooling in the water layer inside the drum, the granulated slag is dehydrated and dried. After removal of the slag from the gutter, it is fed into a layer of water inside the drum with the formation of a single block, the latter is cooled to a temperature below 100 ° C at a maximum temperature in the slag. and then a block of slag is moved in the cavity of the drum along its longitudinal axis onto a die surface with longitudinal ribs, where it is dehydrated at a temperature not lower than 200 ° C. The device comprises a hydrogroove, an inclined drum, divided into sections by transverse annular partitions with material loading devices located in front of the first of them along the movement of the material. The unloading part of the material reloaders passes through the partition, and the boot in front of the partition adjoins the water separator adjacent to the drum surface. The device is equipped with a reverse loader of filtered water. The drum is made with a screen mounted to move material along the longitudinal axis in front of spiral reloaders, the peripheral parts of which are in the form of a cylinder that goes to the center of the drum in a cone with the apex toward the screen, and the central parts are made in the form of blinds. Filtered water reloaders are installed between the first and second baffles in the drum. A cylindrical louvre water separator is installed behind the second partition and is made with an outer conical shell with the apex towards the discharge side of the drum With internal longitudinal ribs. 2 ill. XI CO 2 about

Description

The invention relates to the field of processing metallurgical slag melts and can be used in enterprises of ferrous and non-ferrous metallurgy, as well as the chemical industry for the production of granulated slag.

The closest to the invention in terms of technical nature and the achieved result is a method for the production of grg nullified slag, comprising treating the melt with water jets in a gutter, cooling in a layer of water inside

a rotating cylindrical drum and subsequent dewatering and drying of granular slag during pouring inside a cylindrical drum with water drainage through mesh water separators installed in the openings of the bar-case. bana. 7. ;; ; ; Y; ; 7.;:; . . ..;

The granular slag production apparatus comprises a hydrogut, a rotatable inclined drum with holes in the side surface overlapped by mesh water separators, divided into sections by transverse annular partitions. In front of the first baffle, material loading cranes are located in the direction of movement of the material, the unloading part of which passes through the baffles, and the loading one in front of the baffle is adjacent to the drum surface. 7;

The disadvantage of the method and device implementing it is the increased humidity of the obtained granular slag due to its overcooling in the cooling zone, in the drum, since when it leaves the chute it is distributed by such a layer in the lower part of the cross section of the drum in the water layer directing it and 4 additionally irrigated with water top of the gutter. This takes away the heat of the slag, which is subsequently required to dry it. As a result of this cooling, the slag completely disintegrates into granules in water, which increases the rate of heat transfer and its temperature in this zone does not exceed the temperature of the water, i.e. no more than 80-90 ° С. As the calculation shows, at this temperature, the heat of the slag is clearly not enough to dry it to a moisture content of less than 5%, at which the slag does not freeze. The humidification of the slag is also facilitated by local water drainage in the drum water separation zone through the windows in its body. Water is released from the slag by filtration over the entire area of its contact with the wall of the housing, and is discharged only at the places of the holes. In those areas where there are no openings, the water that separates from the water during rotation of the drum is captured by the material, rises by it and, when poured, moistens the slag again. When pouring material, averaging of moisture occurs over the cross section of the slag layer. Thus, by a known method and device, it is impossible to obtain granular slag of lowered (less than 5%) humidity.

The aim of the invention is to obtain granular slag with a moisture content of less than 5% due to the full utilization of the heat of the slag melt.

In FIG. 1 shows a longitudinal section through the granular slag production apparatus of FIG. 2 is a section AA in FIG. 1. The device consists of a gutter 1 s

a screen 2. which is placed inside the housing 3 of a rotating inclined cylindrical drum -. On the side of the hydrogut 1, the drum casing 3 is covered by a gas-vapor chamber 4, and attached to the end of the casing 3

0 overflow ring 5 with louvre water separator 6. having internal longitudinal ribs. An annular transverse partition .7 and a conical shell 8 s are fixed behind the screen 2 inside the housing 3

5 by an annular partition 9. An annular partition 9 has slots along the outer diameter and rests on a conical shell 8. A conical shell 10 is interconnected along the inner cut-outs of the rebate 7 and 9 10. On the screen side, spiral cranes 11 are attached to the annular partition 7. The peripheral part of the cranes 1: 1 has a cylindrical shape, passing to the center in a conical

5 top towards the screen. The Central part of the reloaders 11 is made in the form of blinds 12. .. 7 .-. . - Between the partitions 7 and 9, reverse reloading devices 13 are installed, the unloading part 0 is removed from the front by the partition 7. Behind the partition 9 there is a cylindrical louvre water separator 14 with internal longitudinal ribs 15, The screen 2 is installed on the under-window.

5 along the axis of the drum two rods 16.

The method is carried out as follows. ..-,.-L--: ...:; .-.- ..: -: .-. 7J: ..; .. l. The slag melt with a temperature of 13.20-1360 ° C is poured into a gutter i, where

0 under the action of water jets, it is partially dispersed and cooled. As the calculations show (V.S.Grigoriev, Y.P. Gindis. Determining the optimal cooling regimes of slag melt in

5 hydro-trough device, NIISP Gosstro, USSR, Kiev, 1968.40 c) the slag residence time in the trench 1 does not exceed 1 second. Accepting the heat transfer coefficient of slag to water equal to 0.5 kW / m2 K (A.E. Shulmey 0 ster. Development, research and implementation of methods of mechanical crushing and cooling of metallurgical melts. Abstract of the dissertation. VNIIMT, Sverdlovsk, 1987, 22 s), and the total area

5 of the slag surface in the gutter, equal to 1 m at a capacity of 3.5 t / min, as shown by the calculations, the slag is cooled in the gutter by no more than 100 ° C. Consequently, the temperature of the slag at the outlet of the gutter will be more than 1200 ° C and it will retain its

in visco-plastic properties. Upon exiting the gutter, the slag together with water collides with the screen 2 and deviates to the lower part of the drum casing 3, which is filled with water between the partition 7 and the overflow ring 5. After deflection by screen 2, the slag is fed by a concentrated stream into the aforementioned layer of water, reunited into a block with the capture of part of the water. When slag is found in water in the form of a block, it cools and hardens. A block of slag is cooled to a temperature of 100-200 ° C below the temperature at which maximum stresses occur. The cooling temperature of the slag is determined by the time spent by the slag block in the water and is controlled by the movement of the screen 2 with the help of rods 16 relative to the reloaders 11. As the slag block moves in the cavity of the casing 3 as a result of its rotation, the slag is removed from under the screen and enters the blades of the reloaders 11, which are captured, is lifted from the water layer and the louvered water separator 14 is reloaded, and temperature stresses are generated and accumulate over the slag cross-section. When overloaded to the louvres x 12, partial slag dewatering is carried out, which helps to keep the slag warm. Filtered water on the water separator 14 flows down along the conical casing 8 to the loading parts of the reverse loaders 13, is captured by them and transferred to the cavity of the drum casing 3 in front of the partition 7, which also contributes to a decrease in the moisture content of the obtained slag and preservation of residual heat.

The greatest effect of thermal crushing of slag is observed at temperatures of about 1000 ° C (A. Ya. Tulaev et al. Road clothes and the use of slag. M., Transport, 1986, 38 s). At these temperatures, maximum thermal stresses are created in the slag block. At the same time, the slag mass still basically retains its shape, but it is penetrated by micro- and macro-dynamics in volume. Reducing the temperature of the block w. At a temperature of 200-100 ° C relative to the above, it ensures the accumulation of temperature stresses in the slag block when it is in the water, and decomposition starts on the reloaders 11 and mainly proceeds and ends on the water separator 14 during periodic lifting and pouring on pef / pax 15, as as a result of the development of temperature stresses, as well as mechanical stresses arising in the slag mass during the fall. Decay of the slag block to the load cells after its removal

from water prevents excessive moisture, which facilitates and increases the degree of dehydration of the resulting slag. The temperature of the slag during dewatering on the water separator 14 is set to not less than 200 ° C, which is ensured by maintaining the temperature during cooling of the slab in front of the reloader 11 by no more than 200 ° C, below the temperature at which the maximum temperature stresses in the slag occur. After dewatering on a water separator 14, the resulting glanslag is poured into the drum body 3, where due to the residual heat of the melt, it is dried to a moisture content of not more than 5%, to be finished and rolled.

An example of a specific implementation of the method.

In a plant for the production of granular slag with a drum cooler with a diameter of 800 mm and a length of 8000 mm, slag is processed for the production of low-carbon ferrochrome with a CaO / 5X2 ratio of 1.8, which has a temperature that causes maximum temperature stresses of 1000 ° C. The slag melt consumption in the experiments was 100 kg / min. Slag temperature is monitored in three zones: in a ditch groove, in a drum in front of the reloaders, and on a dehydrator. Temperature control is carried out by controlling the flow of water to the granulation and by moving the screen relative to the material handlers. Gravel slag exiting the drum is dispersed in fractions and moisture is determined. The intensity of the crushing process is determined by the fraction yield of a fraction of 5 mm.

The results of the experiments are shown in the table.

Thus, the results of the tests of the method show that the PUF during granulation in, in accordance with these modes, is obtained by utilizing and using the heat of slag granshlag with a moisture content of not more than 5%.

FORMULA AND SECTION

1. Method for the production of granular slag in a growing drum by draining the slag melt into a gutter, removing it from the gutter with jets and thermally crushing it at a temperature at which maximum stresses arise in the slag, followed by cooling in a layer of water inside the drum, dewatering and drying granulated slag characterized in that, in order to obtain granulated slag with a moisture content of less than 5% due to the full use of the heat of the slag melt

the slag after removal from the hydrogut is fed into the water layer inside the drum with the formation of a single block, cool the latter to a temperature below the temperature at which the maximum stresses in the slag occur, by 100-200 °, and then move the slag block in the cavity of the drum along its longitudinal axis on a filtering surface with longitudinal ribs, where it is dehydrated at a temperature of at least 200 ° C.

2. A device for the production of granular slag in a rotating drum, including a hydro-groove, an inclined drum, divided into sections by transverse annular partitions with the material in front of the first of them, as part of the material transfer process, the part of the compressor passes through the partition, and the boot in front of the partition close to the surface of the drum, and a water separator,

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characterized in that, in order to obtain granulated slag with a possibility of less than 5% due to the full utilization of the heat of the slag melt, it is equipped with a reverse reloading of filtered water, the drum is made with a screen mounted to move along the longitudinal axis in front of the spiral material reloaders, peripheral parts which are in the form of a cylinder, passing to the center of the drum in a cone with the apex toward the screen, and the central parts are made in the form of blinds, the reverse overload filters -water are mounted between the first and second baffles in the drum, a cylindrical louver water separator installed in the second partition wall and has an external cone-shaped shell with the apex towards the discharge portion of the drum and internal longitudinal ribs.

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