SU1316987A1 - Method for treating slag melt and device for effecting same - Google Patents

Abstract

This invention relates to a process for the processing of metallurgical slags, for example blast furnaces, into fertilizers and can be used in the manufacture of fertilizers with the addition of trace elements and other nutritional components. In order to increase the productivity and quality of the finished product, slag melt is fed into a cyclone melting furnace with a speed equal to 0.05-0.1 energy carrier velocity, mixed with molten additives, and with stirring the mixture is heated to a temperature of 150-300 ° C above melting. c (LL CA9 cc from 00 vl f

Description

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and the cooling is carried out at a rate of 1-100-400 ° C / s. The method is carried out in a device whose vertical chamber 1 is designed to expand downwards and is tangentially mounted in an annular bottom recess in the same direction as the sliders 2 for supplying lined energy carrier branch pipes for the supply of molten slag, while expanded

The invention relates to the processing technology of metallurgical donkeys, for example blast furnaces, with y / dobne and can be used in the manufacture of fertilizers with the addition of trace elements and other nutrients.

The purpose of the invention is to increase the productivity and quality of the finished product.

1 shows a device for processing molten slag; fig 2 is the same, top view.

The device consists of a vertically mounted working chamber 1, in the upper part of which nozzles 2 are installed tangentially for supplying energy carrier with fuel supply unit 3. The upper chamber lid has holes with chutes 4 for introducing solid additives. In the lower part of the chamber along its axis there is a clamp 5, which forms an annular bottom cavity with its outer surface with the inner surface of the chamber wall. In the area chamber; (annular recess) are installed tangentially lined nozzles 6, associated with a supply system of liquid slag - with a capacity of 7, supply nozzles 6 mj iaKa are installed in one direction with energy supply nozzles. In the vessel 7 there is a liquid slag under pressure resulting from the supply of high pressure gas to the vessel, for example, from a cyclone furnace.

Camera 1 is at a height with; extended inner diameter D in H1-skny its parts. The extended portion smoothly mates with the upper portion at the height of the chamber constituting

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the chamber section is adjacent to the upper section at a height equal to 0.3-0.5 of the chamber height from the bottom of the annular recess, and the inner diameter of the lower section is 1.5-2.5 of the inner diameter of the upper section, with the angle formed by the tangent at the junction point of the camera sections, it is 10–3 o to its vertical axis, h., p. f-ly, 2 silt, 2 tab.

0.3-0.5 height of the camera. The height of the upper section to the interface point h and the height of the lower section N. Inner diameter

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lower section

D

5 is greater than the diameter d of the inner upper portion 1.5-2.5 times. The angle d formed by the tangent drawn at the conjugation point of the chamber sections is 10-30 to its vertical axis.

Pinch 5 is connected to a sump tank 8, having gas inlets in the upper part, and a hole in the bottom for a metal drain. The digger 8 is provided with a chute 9 for discharging slag onto cooled rolls 10. The device is provided with gear-roll rollers 1 1 for crushing the slag tape produced in rolls 10.

 The device works as follows.

Alloying finely ground up. The cans of a given chemical composition are fed into the combustion chamber (in the upper part of chamber 1) through chutes 4. At the same time, the mixture of air with gaseous fuel through nozzles 2 enters the combustion chamber. The combustion products of the fuel due to the tangential installation of nozzles 2 form a swirling high-temperature, turbulent gas flow. Particles of alloying elements, falling into this stream, instantly melt and due to centrifugal forces are thrown onto the walls of the combustion chamber and the working chamber 1, where they form a film of melt on the surface of the skull lining of the chamber, which flows into the annular recess

The bath is a bath. In this bath through tangentially installed connections 6

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due to capacity 7, liquid slag enters under pressure, which is heated to a higher temperature (1550-1700 ° C) due to the heat of the high-temperature gas flow and the heat of the doping additives entering the slag in the form of a melt, which significantly reduces the viscosity slag, improve the process of mixing slag and additives.

Efficient mixing of slag and additives also contributes to the one-sided tangential supply of slag and energy carrier, due to which it is homogenized, averaged by chemical composition and the quality of the finished product.

From the working chamber 1 molten slag and additives and gases through the pinch 5 enter the digger-settler 8, where the metal is separated from the molten slag and the metal is periodically released through the bottom hole. The slag 13 slag continuously along the chute 9 is fed to the solution of the rolls 10, where the melt is cooled at a speed of 1100-1400 ° C / s. Then, the resulting thin slag ribbon is crushed in rollers 11, until fertilizer 12 is obtained. Combustion products from the storage facility 8 can be fed through gas ducts, for example, to a heat-using unit (not shown).

By performing the expanded lower portion of the working chamber, the slag melt is sufficiently heated and the alloying components are maintained in the molten state. If the extended section of the chamber is greater than 0.5 of the height of the chamber, then the residence time of the melt of trace elements additives is not enough to overheat them, and if less than 0.3 of the height of the working chamber, then strong overheating of the additives may occur, which leads to their gaseous state example, of the easily volatile component of boron, reducing them in the finished product.

If the diameter of the lower section is fulfilled with a value less than 1.5 times relative to the diameter of the upper section, the slag melt can rise along the height of the chamber by swirling the flow to the combustion zone and may overheat and degrade the slag melt displacement from melt additives. Increase the diameter of the bottom

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more than 2.5 times the diameter of the upper portion of the chamber actually reduces the rate of twisting of the gas

flow affects the heat and mass transfer and the quality of the finished product.

The tilt angle of the working chamber at the interface, i.e. the angle d formed by the tangent drawn at the point t must be 10-30. As the angle decreases, the inclined section of the chamber increases in height, which leads to overheating of the melt of alloying additives and, accordingly, to their transition to a gaseous state. With an increase in the angle of more than 30, the particles of the additives fall into the molten slag in the solid state, which causes the uniformity of their distribution in the volume of the slag melt, i.e. degrades the quality of the finished product.

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The need to feed the slag melt into the lower zone of the working chamber is due to the fact that when it is fed into the upper zone of the chamber, the slag melt overheats, the solid particles of the added additives do not have time to melt and get into the slag melt in a solid state of aggregation and their uniformity with slag melt deteriorates . In addition, some dopants, such as manganese oxide, having a melting point higher than that of the slag, may not melt at all.

Example. Liquid blast-furnace slag with a temperature is supplied to a cyclone furnace with an outflow rate through nozzles of 10 m / s. Additives of ferroboron slag and pi - liter cinders were used as alloying components. The amount of injected liquid slag was 80%, and the amount of injected additives was 10% ferroboron, and 10% pyrite cinder. Additives were introduced into the furnace from above through heat. Tangentially, the working chamber in its upper part was fed a mixture of natural gas with air with an outflow rate from the nozzles equal to 150 m / s. The heating temperature of the furnace was supported by fuel consumption (). To determine the boundary values of the temperature of the overheating of the molten slag mixture and additives, the fuel consumption with air was varied by changing the melt temperature.

WA on the SO-3-ZZ C above the mixture melting temperature.

The chemical composition of the starting material and product is given in table 1.

Slag was poured from the pigmer into the lumen of the cooled rolls. The cooling rate was 1250 C / s. The hardened slag in the form of a ribbon with a thickness of 88 mm was crushed in toothed rollers. In order to determine the boundary values of the cooling rate, the roll solution and slag consumption were changed, and thereby the melt cooling intensity was varied in the SOOOO-MZO range of s / s (see table 2).

The rate of slag outflow from the nozzles, when it was fed into the furnace, was 0.05-0.1, the rate of outflow of energy carrier, which is 100-150 m / s. When the slag outflow rate is less than the specified value, between the molten slag melt and the additives, the heat and mass transfer process proceeds slowly, which makes it necessary to increase the residence time of the melt in the furnace. In addition, at low speed of movement of the melt, the process of homogenization deteriorates. If the flow rate increases by more than 0.1, the energy consumption increases significantly, and in fact the process of homogenization does not improve.

Table 2 shows the effect of overheating of the melt mixture of slag and additives, as well as the rate of cooling of the melt on the content of the lemon-soluble form of trace elements.

From Table 2 it can be seen that the dilution of trace elements in the 2% citric lime lot and, accordingly, the quality of the fertilizer deteriorates with the parameters of the superheat temperature and the cooling rate below and above indicated in the claims. Although the indices increase slightly with an increase in the cooling rate, it is difficult to increase the cooling rate above 400 ° C / s.

The proposed method for the production of fertilizers and the device for its implementation improve the quality of mineral fertilizers and the productivity of the process.

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Claims (3)

1. The method of processing molten slag, including the flow of the melt slag in a cyclone melting furnace, continuous loading of a specified amount of solid additives into it from above with supply of gaseous energy carrier to the furnace, melt mixing slag and additives, cooling and grinding, characterized by chth-o in order to increase productivity and quality of the finished product, molten slag is fed into the furnace at a speed equal to 0.05-0.1 speed energy, before mixing the molten slag and additives, the latter is melted, with stirring, the mixture is heated to a temperature at a temperature of 150-300 ° C above its melting point, and cooling is carried out at a speed of 1100-1400 s / s. 2. A device for processing molten slag, containing a vertical chamber with tangentially installed energy supply nozzles in its upper part, branch pipes for supplying solid additives, connected with the settler, pinch, Located in the lower part of the chamber with the formation of an annular bottom recess, characterized in that, in order to improve the performance and quality of the finished ProDZP: this vertical chamber is made with expansion downwards and is equipped with tangentially installed in the annular recess in the same direction with nozzles for supplying energy carrier with lined nozzles for supplying molten slag, while the expanded portion of the chamber smoothly mates with the upper portion at a height equal to 0.3-0.5 of the height of the chamber from the bottom of the annular recess, and the inner diameter of the lower portion is 1.5-2.5 of the inner diameter of the upper portion. 3. The device according to claim 2, about tl, which is the fact that the angle formed by the tangent at the junction point of the sections of the chamber is 10-30 to its vertical axis. Alkaline components Table 1 C1 r N - vO CM ech f O CM CO r 1L o T - " r CO T r. F g- 4f vO O l. vO r vO r sr y- (L vO  r f - r r 3 o c u-l - about CO vo vO in vr (3 - in in Cf on G00 U1 CO r CHO VO r in about r fo cho yi -a 04 vO “U-i r D (L in CM i r in CM oo vD CO r t en about "W About midrange CQ O u WITH N1 gas 2 3 CPU I