RU2614293C2 - Method of low-autogenous raw material processing in flash smelting furnaces - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: according to method, low-autogenous raw material processing in flash smelting furnace comprises supplying a metal-containing charge and flux as charge-gas flame to reaction zone of the said furnace by stream of oxygen or air enriched with oxygen, charge melting occurs to form a molten matte and slag, their separation by settling, separate liquid melting products and gases outputing. Charge composition comprises carbon containing reducer with fineness of 3-15 mm in an amount of 0.4 to 5 tons per hour in at volume ratio of 1:30 to 1:2 relative to flux.

EFFECT: increased productivity of flash smelting process, reduced probability of scull formation in uptake and slag bath of furnace, and also reduced losses of non-ferrous metals with waste slag.

2 cl, 3 tbl

Description

The invention relates to the field of metallurgy of non-ferrous metals, in particular to the melting of raw materials containing non-ferrous metals in a suspension smelting furnace, and can be used for melting low-autogenous raw materials, to reduce losses of non-ferrous metals with slags and to reduce dust formation in the sump and pharmacy of suspended smelting furnaces (PVP )

The invention is aimed at involving low autogenous non-ferrous metals (sulphide ore concentrates, concentrates of technogenic deposits) in PVP processing, characterized by a low sulfur content, i.e., raw materials, during the oxidative smelting of which in the suspended state insufficient heat is generated to ensure the heat balance of the furnace.

A known method of smelting sulfide copper ores and concentrates in suspension. To increase the degree of reduction of the slag magnetite, a finely divided carbon-containing reducing agent - dusty coal, is fed through the burner together with sulfide copper concentrate, and at least part of it is blown into the lower part of the furnace shaft, where the oxygen partial pressure is low. As a result, carbon particles do not burn, but are captured by the molten particles of the mixture and settle in the bottom of the mine. The size of the coal particles is 30% - 44 μm and 70% - 10 μm, and the pipe for injection is directed to the slag layer of the sump, where iron oxides are re-reduced (US patent No. 5912401). The method is based on the high reducing ability of dusty coal under conditions of low partial oxygen pressure in the lower horizons of the reaction shaft. The disadvantage of this method is to work with dusty coal: it is necessary to redistribute the grinding and drying of coal, as well as transportation of explosive coal dust to the furnace.

Also known is a method of melting sulfide copper ores and concentrates in suspension. To prevent excessive formation and precipitation of magnetite in the slag melt, as well as to reduce copper and slag losses through the shaft of the reaction shaft, a carbon-containing reducing agent, dusty coal, containing 80% of the mass, is fed into the furnace. and more carbon. The particle size of the feed said reducing agent is: 65% or more - 100 microns, 25% or more + 44-100 microns (US patent No. 5662730). The disadvantage of this method is the need to work with dusty coal: the redistribution of grinding and drying of coal, as well as transportation of explosive coal dust to the furnace.

A known method of producing nickel matte with a low iron content by melting sulfide concentrates in a suspension smelting furnace, this concentrate together with oxidizing gases moving from top to bottom, and the reaction gases are discharged through a horizontal settler into a vertically rising hog. The method is characterized in that the magnetite and nickel oxide formed during the oxidation of the sulfide concentrate are reduced in the lower part of the furnace shaft as a result of an increase in the partial pressure of sulfur in the gases formed and / or a decrease in the partial pressure of oxygen even before the transition of the gases of the reaction shaft (RS) to the furnace sump. This prevents oxidation of matte in the sump and the transition of nickel oxide to slag (US patent No. 3754891). The method is based on the supply of a liquid or gaseous reducing agent to the lower third of the reaction shaft through tuyeres installed in the RS casing in a plane perpendicular to the RS axis. In this case, the capture of the reducing agent is inevitable by an ascending near-wall gas flow, which will lead to a violation of the integrity of the skull on the firing surface of the RC and an increase in the thermal load on the cooling elements.

A known method of producing copper matte with a low iron content by melting a sulfide copper concentrate in a suspension smelting furnace, the sulfide copper concentrate along with oxidizing gases moving from top to bottom, and the reaction gases are discharged through a horizontal sump into a vertically rising hog. The method is characterized in that in order to reduce copper loss with slag, as well as to reduce scatter formation in the furnace pharmacy, a crushed carbon-containing reducing agent (Takaaki Shibata. - Energy recovery and substitute fuel technology in the flash smelting furnace with electrodes (FSFE) at Tamano smelter. - Metallurgical Review of MMIJ.- Vol 7. - No. 2. - November 1990. - P 1-23.). The amount of crushed coal or coke supplied is 2.7-4.2% by weight of the processed sulphide copper concentrate (28% by weight of Cu). The size of the pieces introduced into the mixture of coke is 1-2 mm The oxygen content in the blast reaches 30% vol. The temperature of the blast reaches 400 ° C. The copper content in the resulting matte is 60% of the mass. The method adopted for the closest analogue (prototype), however, it has the following disadvantages:

1. The decrease in the overhaul period of the furnace

1.1. A significant role in the wear rate of the lining is played by the place where the carbon-containing reducing agent is fed into the unit. In this case, the feed point is the reaction shaft. The second factor, which plays a significant role, is the size of the mentioned reducing agent - 1-2 mm. These two factors increase the rate of reactions of carbon interaction with the lining of the reaction shaft (RS) and its adjacent to the sump. With the selected method of supplying the carbon-containing reducing agent to the furnace, this carbon-containing reducing agent and its oxidation products are intensively distilled from the center to the walls of the RS and subsequently the sump located under the RS. In this case, the contact of the carbon-containing reducing agent with the skull of the RC and the sump occurs and, as a result, the destruction of the skull and premature wear of the lining.

In addition, the carbon-containing reducing agent destroys the protective oxide films on copper caissons, which can also lead to burnout of the latter and an emergency exit of the melt.

1.2. The presence of small particles of a carbon-containing reducing agent in the charge / KVS flare (oxygen-air mixture) leads to the fact that part of the oxygen in the blast is used to burn the carbon-containing reducing agent. This leads to two negative consequences - it becomes more difficult to maintain the optimal oxygen / charge ratio necessary to obtain the required matte quality and, in addition, the temperatures in the CW and the furnace settler increase significantly, which increases the heat load on the CW arch and the furnace settler arch and reduces their term operation.

The objective of the invention is the involvement in the processing of sulphurous, finely divided raw materials, reducing the content of non-ferrous metals in the slag, reducing the likelihood of nastyleobrazovaniya in the pharmacy and the settling tank of the smelting furnace.

The technical result of the claimed invention is to increase the productivity of the process of suspended smelting, reduce the likelihood of nastyleobrazovaniya in a drugstore and slag bath furnace, reduce losses of non-ferrous metals with dump slag.

The specified technical result is achieved in that in the proposed method, comprising supplying a metal-containing charge and flux in the form of a charge gas torch into the reaction zone of the above-mentioned furnace with a stream of oxygen or oxygen enriched oxygen, melting the charge with the formation of matte and slag melts, separating the latter by settling, separate liquid output melting products and gases, in contrast to the closest analogue, a carbon-containing reducing agent with a grain size of 3-15 mm in volume ratios with river sand is introduced into the mixture using used as a flux, from 1:30 to 1: 2.

As a carbon-containing reducing agent, the introduction of coal or products of its processing (coke, semi-coke, coal mines, etc.) is possible in the composition of the charge.

The essence of the proposed method is as follows.

The sulphide concentrate containing non-ferrous metals is melted in a suspension smelting furnace (PVP) with a horizontal or vertical charge feeding scheme. The method includes feeding crushed sulfide concentrates, fluxes, an oxygen-containing gas and a solid carbon-containing reducing agent into the furnace, smelting, separation of the smelting products into matte and slag, and the periodic delivery of smelting products. According to the invention, a carbon-containing reducing agent with a particle size of 3-15 mm in a volume ratio with a flux of 1:30 to 1: 2 is fed into the furnace together with the material being processed, that is, the carbon-containing reducing agent is a component of the charge.

The implementation of the method is carried out in the PVP with a vertical or horizontal charge supply scheme.

Relatively large particles of a carbon-containing reducing agent, 3–15 mm in size, after being injected into the reaction shaft (RS) as a part of the charge through the atomizer during the downward flow in the first two thirds of the RS are heated without entering into an oxidation reaction. The oxidation reaction of the reducing agent carbon to carbon monoxide with residual (unreacted with metal sulfides and gray charge) oxygen and subsequent reducing reactions with the mine product (molten metal sulfides and oxides) occur in the lower third of the reaction shaft (RS) of the furnace. This behavior of the carbon-containing reducing agent in the RS makes it impossible to interact with this reducer with the skull of the RS. At the same time, interacting with excess blast oxygen not reacted with the charge, the carbon-containing reducing agent supplied by the proposed method prevents the small particles of the metal-containing charge from being oxidized to higher refractory oxides.

The natural content of free oxygen in the furnace gases of PVP is 3-5% vol. Free oxygen interacts with small oxidized and fused particles of a metal-containing mixture, leading to their oxidation to higher refractory oxides. The formation of refractory oxides in the gas-dust flow of PVP leads to a deterioration in the conditions of particle growth and their absorption by the melt, to an increase in dust removal from PVP, to a tendency to sedimentation in the PVP slag bath, to an increase in the content of magnetite and, accordingly, non-ferrous metals in the PVP slag.

The solid carbon-containing reducing agent supplied by the proposed method in PVP binds excess oxygen of the blast, preventing the small particles of the metal-containing charge from being oxidized to higher refractory oxides, which limits the development of the above negative processes.

The oxidation of the supplied solid carbon-containing reducing agent is accompanied by the release of additional heat required to compensate for the lack of heat and stabilize the heat balance of the PVP during the processing of low-autogenous raw materials.

When implementing the method in PVP with a horizontal charge supply scheme, the mechanism of action of a solid carbon-containing reducing agent is similar.

Justification of the parameters

1. The rationale for the hourly consumption of solid carbon-containing reducing agent introduced into the composition of the PVP mixture

The volume of gases exhausted from RS PVP NMZ (Nadezhda Metallurgical Plant) is 55-65 thousand nm ³ / hour. The oxygen content in the gas RH is about 3% volume, which is 1.7-2.0 thousand nm ³ / hour of oxygen. To neutralize the indicated amount of oxygen, a solid mineral carbon-containing reducing agent can be used, for example, coal or products of its processing: namely, coke, semi-coke, coal mines, etc.

The interaction of carbon with oxygen is realized to CO and CO ₂ :

Those. To bind “unreacted” oxygen to the gas stream of the RSh, 0.9–2.2 t / h of carbon will be required. If we take the carbon content in the coal of the Kayerkansky opencast (the most affordable coal for metallurgical enterprises of the Norilsk industrial region) about 60% of the mass. (in addition to carbon, the coal in question contains up to 30% by weight of ash and about 10% by weight of the sum of N ₂ , O ₂ , H ₂ , etc.), then the coal consumption will be 1.5-3.7 t / h. Based on the presented values, the average coal consumption should be about 2.0-2.5 tons / hour.

A statistical analysis of the data reflecting the heat balance of the PVP NMZ showed that it is possible to accept the heat balance of the smelting at an hourly flow rate of the metal-containing part of the charge at the level of 170 tons per hour. The sulfur content in the metal-containing part of the charge is 27% of the mass.

The decrease in the autogenicity of the sulfide concentrate is due, first of all, to a decrease in its sulfur content.

Burning one kilogram of sulfur according to a simplified reaction:

S + O ₂ = SO ₂

accompanied by the release of approximately 11.3 MJ of heat (in the temperature range of 1200-1400 ° C, this value varies slightly). A similar amount of heat is generated during the combustion of 0.122 kg of carbon by the reaction:

C + O ₂ = CO ₂

or 0.162 kg of carbon by reaction:

2C + O ₂ = 2CO

Therefore, a decrease in the sulfur content in the charge by 1% of the mass. accompanied by a decrease in the amount of sulfur supplied to the PVP by (170 * 27/100 - 170 * 26/100) = 1.7 t / h.

Simplistically, for the heat balance of the heat to remain unchanged, the indicated decrease in the sulfur content in the charge can be compensated by introducing 1.7 * 0.162 = 0.27 t / h of carbon into the charge. Given the carbon content in the coal of the Kayerkan coal mine, with a decrease in the sulfur content in the charge by 1% of the mass. (when processing 170 tons per hour of metal-containing charge in PVP), the heat balance of PVP is compensated when 0.27 / 0.6 = 0.5 tons per hour of coal is introduced into the composition of the charge.

As the practice of operation of PVP NMZ has shown, the heat balance deficit becomes critical with a decrease in the sulfur content in the charge by 2-3% of the mass. Therefore, to compensate for the heat deficit in the PVP while reducing the sulfur content in the metal-containing part of the charge by 2-3% of the mass. (decrease in the autogenous nature of raw materials), it is advisable to introduce into the charge mixture (ceteris paribus technological conditions for PVP operation) up to 1.5 t / h of coal from the Kayerkan coal mine.

The introduction of about 2.0-2.5 t / h of coal from the Kayerkan open pit coal into the PVP batch of NMZ will not only neutralize the excess oxygen naturally contained in the PVP gases, but also compensate for the heat balance deficit in the PVP during the processing of low-autogenous raw materials.

2. The rationale for the particle size of a solid carbon-containing reducing agent introduced into the composition of the PVP mixture

As noted above, to prevent the destruction of the skull of the reaction shaft (RS) of the suspension smelting furnace (PVP), the interaction of particles of a solid carbon-containing reducing agent with residual blast oxygen must be realized in the lower horizons of the RS. It is known that the reaction of the interaction of solid carbon with oxygen in the gas phase to a significant extent occurs only at temperatures above 500-600 ° C. Therefore, in order to prevent this interaction in the upper horizons of the RS, it is necessary that the particles of the solid carbon-containing reducing agent are heated to a temperature of 600 ° C only when the lower horizons of the RS are reached. This problem is solved by selecting the particle size of the solid carbon-containing reducing agent introduced into the mixture.

Thus, the purpose of the calculation necessary to justify the particle size of the solid carbon-containing reducing agent was to build the dependence of the average temperature of the coal particle fed into the PVP as a part of the mixture and reaching the lower horizons of the RS on the particle size. The particle size of the solid carbon-containing reducing agent is selected based on estimates of the time required to heat the coal particles in the torch of the charge burner to a temperature of 600 ° C. It is accepted that a coal particle will interact with oxygen in the gas phase at temperatures above 600 ° C.

Accepted initial data for subsequent calculation:

Average gas parameters:

- the average composition of gases RH (% vol.):

32.9 SO ₂ ; 0.2 SO ₃ ; 1.9 H ₂ O; 0.4 CO ₂ ; 3.0 O ₂ ; 61.6 N ₂ ;

- gas flow: Q = 43300 nm ³ / h;

- average gas temperature: t _g = 1400 ° C

- the properties of the gas correspond to an ideal gas.

The average parameters of a coal particle:

- form: to simplify the calculation method adopted spherical;

- diameter: options - d _h = 1, 2, 4, 7 and 10 mm;

- the density, like other thermophysical parameters of the particle, corresponds to anthracite: ρ _h = 1440 kg / m ³ ;

- specific heat capacity: c _pv = 0.226 cc / kg / K;

- thermal conductivity: λ _h = 0.328 W / m / K;

- initial temperature: t ₀ = 20 ° C;

- initial feed rate: w ₀ = 0 m / s;

Dimensions of the reaction shaft

- inner diameter: D = 7500 mm;

- the distance from the firing surface of the arch to the melt N = 8.2 m

Billing

Using temperature and gas composition, gas parameters were calculated:

- density ρ _g = 0.2818 kg / m ³ ,

- viscosity μ _g = 667.8 Pa * s,

- thermal conductivity λ _g = 0,1004 W / m / K,

- specific heat with _pg = 1069 J / kg / K.

The linear gas velocity was calculated by the formula:

where F = πD ^2/4 - flow area of the mine,

Q is the gas flow rate,

t _g - average gas temperature.

When calculating with numerical values of the values, the linear gas velocity was w _g = 1.67 m / s.

The residence time of particles in the mine τ was calculated approximately by two characteristic parameters, which can be determined as follows:

1. The time with steady-state sedimentation deposition τ ₁ calculated by the formula:

where w _g is the linear velocity of the gas;

w _s is the sedimentation rate of particles.

Particle sedimentation rate - w _{s was} determined by the method, according to which the drag coefficient f was first calculated by the following formula:

where r _h = d _h / 2 is the particle radius,

d _h - particle diameter,

ρ _g is the density of the gas,

ρ _h - particle density,

g is the acceleration of gravity,

μ _g is the viscosity of the gas.

Then, according to the tabular data, the Reynolds criterion, Re _s , was determined as a function of the resistance coefficient f.

Finally, we calculate the sedimentation rate of particles (w _s ) according to the formula:

where Re _s is the Reynolds criterion,

μ _g is the viscosity of the gas,

d _h - particle diameter,

ρ _g is the density of the gas.

2. The travel time according to the laws of free fall τ _{2 was} calculated by the formula:

where H is the distance from the firing surface of the arch to the melt,

g is the acceleration of gravity.

The desired residence time of particles in the mine τ was calculated by the formula:

The result of the calculation according to formula 6 gives an exact coincidence with the two limiting cases τ = τ ₁ (where τ ₁ is the particle motion time with steady sedimentation deposition) for the deposition of small particles (d _h = 1-4 mm) and τ = τ ₂ (where τ ₂ - time of movement according to the laws of free fall) for the movement of lumpy material (d _h = 7-10 mm) according to the law of free fall. In the intermediate region, the formula approximately correctly takes into account the inhibitory effect of gas on particles, which is confirmed by control calculations using a more accurate sedimentation deposition technique. The average particle velocity w _{h was} calculated by the formula:

where H is the distance from the firing surface of the arch to the melt,

τ is the residence time of particles in the mine.

In this case, the average velocity of relative motion of gas and particle w _rel necessary for further calculations is calculated as follows:

where w _h is the average particle velocity,

w _g is the linear velocity of the gas.

The thermal diffusivity of coal particles a was determined by the formula:

where λ _h - thermal conductivity of coal,

ρ _h is the density of coal,

with _rh is the specific heat of coal.

When calculating with numerical values of the values (given in the accepted source data), it was shown that the thermal diffusivity of coal particles is a = 2.408⋅10 ^-7 m ² / s.

The conditional coefficient of radiant heat transfer α _{p was} determined by the expression:

where q _p is the radiation component of the heat flux,

t _g - average gas temperature,

t _p - average surface temperature of the particle.

Particle surface temperature is a variable that can vary from 20 ° C to gas temperature (1400 ° C). The constancy of this parameter makes it possible to perform the calculation of heat transfer without complex iterative procedures. Only for the calculation of heat transfer, a value of 700 ° C is adopted, which corresponds to the average value from the above temperature range of 20-1400 ° C.

The radiation component of the heat flux q _p was estimated from the well-known dependence for radiant heat transfer between completely black media:

where t _g is the average temperature of the gas,

t _p - the average surface temperature of the particles,

5.67⋅10 ^-8 - Stefan-Boltzmann constant W / (m ² ⋅К ⁴ ).

When conducting calculations with numerical values of the quantities, it was shown that the conditional coefficient of radiant heat transfer α _p = 562 W / m ² / K.

Depending on the particle radius r _h , the Fourier criterion (Fo) was determined:

where a is the coefficient of thermal diffusivity of coal particles, m ² / s,

τ is the residence time of the particle in the mine,

r _h is the radius of the particle,

as well as the Nusselt criterion (Nu) for the convective component of the heat transfer of gas and particles:

where Re = w _rel d _h ρ _g / μ _g is the Reynolds criterion for the average speed of the relative motion of gas and particles,

Pr = μ _g with _rg / λ _g - Prandtl test,

w _rel - the average speed of the relative motion of gas and particles,

d _h - particle diameter,

ρ _g is the density of the gas,

μ _g - gas viscosity Pa * s,

with _rg is the specific heat of gas,

λ _g - thermal conductivity of the gas.

From the Nu value, the coefficient of the convective heat transfer component α _{k was} then determined:

where Nu is the Nusselt criterion,

λ _g - thermal conductivity of the gas,

d _h - particle diameter.

Further, by the total heat transfer coefficient, taking into account the convection and radiant component of heat transfer (α = α _p + α _k ), the Biot criterion (Bi) was determined:

where α is the heat transfer coefficient (W / m ² ⋅K),

r _h is the radius of the particle,

λ _h - thermal conductivity of a coal particle,

For each particle size, using the calculated criteria of Biot (Bi) and Fourier (Fo), the parameter θ (dimensionless temperature) and the desired average temperature of the coal particle t _h at the moment of its exit from the reaction shaft were determined graphically:

where t _g is the average temperature of the gas,

θ = (t _h -t _g ) / (t ₀ -t _g ) is the dimensionless temperature,

t ₀ - initial particle temperature, ° C (adopted 20 ° C).

The calculation results are shown in table 1 (figure 1).

As can be seen from the data presented in table 1, coal particles with a particle size of more than 3-4 mm reached the "reaction temperature" when leaving the RS PVP. Smaller particles warm up faster and, accordingly, their interaction with blast oxygen or the skull of the PVP reaction shaft in its upper horizons is possible, which is extremely undesirable. Larger particles, according to the calculation results, reached the “reaction temperature” later. At the same time, taking into account some assumptions of the performed calculations, the existence of zones of high (above 1500 ° C) temperatures in the flare of a PVP charge burner, the existence of regions of high oxygen content, as well as the heating of carbon particles as a result of their combustion, the recommended particle size of a carbon-containing solid reducing agent was increased . As the observations made during pilot industrial tests (OPI) showed, the results of which are discussed below, when coal PVP with a particle size of more than 20 mm is introduced into the mixture, individual particles of coal are deposited on the surface of the slag bath, which can negatively affect the state of the scum of the settler PVP.

Thus, the recommended particle size range of coal introduced into the composition of the PVP mixture was 3-15 mm. The recommended consumption of solid carbon-containing reducing agent is from 0.4 to 5 tons per hour.

The method is illustrated by examples.

Suspended smelting furnaces of the Nadezhda Metallurgical Plant (NMZ) process copper-nickel sulfide concentrates to produce matte and slag sent to depletion furnaces. The deterioration in the quality of the processed concentrates referred to, consisting in a decrease in their autogeneity, i.e. a decrease in the content of sulfur and sulfide iron in concentrates, which are the main heat source of PVP NMZ, has led to an increase in the probability of deposit formation. In order to combat scaling in the PVP NMZ, an OPI was implemented providing for the introduction of a fine fraction (3-15 mm) of coal from the Kayerkan coal mine (coal mine) into the composition of the PVP charge. OPI was carried out at PVP-2 NMZ.

Coal min was supplied together with flux. The mixture, flux + coal was prepared in the ore yard and fed into the furnace along the path of sand supply and drying.

The supply of coal mines in the PVP was increased in stages. The duration of each stage ranged from 24 to 72 hours. Periodically, the supply of the coal block was stopped to fix the main performance indicators of the PVP without introducing coal into the composition of the mixture. The total duration of the OPI was more than 30 days, during which more than 470 tons of coal mines were processed.

The mass consumption of coal mines at different volume ratios of coal mines: river sand (PVP NMZ flux) is given below (bulk density of coal mines 0.86 t / m ³ , bulk weight of river sand 1.5 t / m ³ ):

1: 30-1.20% or 0.4 t / h (when loading 30 t / h of sand and sand);

1: 20-1.78% or 0.5 t / h (with a load of 30 t / h of sand and bayonet);

1: 15-2.36% or 0.7 t / h (with a load of 30 t / h of sand and bayonet);

1: 10-3.49% or 1.0 t / h (with a load of 30 t / h of sand and bayonet);

1: 5-6.75% or 2.0 t / h (with a load of 30 t / h of sand and bayonet);

1: 4-8.30% or 2.5 t / h (with a load of 30 t / h of sand and bayonet);

1: 2-15.33% or 5.0 t / h (with a load of 30 t / h of sand and bayonet).

During the OPI period, the temperature regime of drying sand and coal mines in a drum sand dryer, the temperature in the settling tank and the PVP-2 pharmacy were monitored, the draft regime of the PVP-2 was changed, the temperature in the electrostatic precipitators, the temperature of the cooling water at the outlet of the charge atomizer, the heat transfer of the pharmacy and the settler . The control was carried out according to the operational data of the information base of the control system “NMZ XIS”.

During the OPI, the temperatures of the structural elements of the reaction shaft, the casing of the pharmacy, and the temperature of the products of PVP-2 melting (matte and slag) were monitored.

Inspection of PVP-2 before the start of the pilot survey showed the presence of accidents in the area of the 1st, 2nd, 3rd, 6th slag holes. The viewing window near the 1st and 6th slag boreholes was completely closed with charge material and overlay. Thus, PVP-2 was in an extremely unsatisfactory condition, which significantly limited its performance.

During the run, the temperature on the surface of uncooled RS structures did not exceed 100 ° C, the temperature of the pharmacy casing was not higher than 250 ° C. The temperature in the sump during the OPI period increased by 13 ° C, the temperature in the pharmacy increased by 329 ° C, which indicates the predicted zone of coal oxidation in the lower area of the CW and the sump. Indeed, the heat transfer in the sump increased by 849 MJ / hour (about 8% relative). The matte temperature increased on average by 50 ° C, slag - by 13 ° C.

With an increase in the consumption of coal mines, an insignificant (by 5–10% rel.) Decrease in the content of sulfur dioxide in the exhaust gases was observed.

When loading a coal mine, there was a tendency to a decrease in the magnetite content in the dust of the waste gas boiler (KU). Without loading a coal mine, the average content of magnetite in the KU dust was 38.4% of the mass. with the loading of the coal mine - 32.7% of the mass. A decrease in magnetite in PVP-2 slags was noted — from 7-8 to 5-6% of the mass. The data in table 2 (figure 2) reflect the change in the content of the main components of the slag due to the introduction of coal in the composition of the PVP-2.

Inspection of PVP-2 at the end of the OPI showed that the coating in the sump is partially eroded at the 3rd and 6th slag boreholes and has the appearance of a “visor” on the wall of PVP-2. The viewing window near the 1st and 6th slag holes was freed from the cover. Thus, despite the significant residual content in the PVP-2, the general condition improved, which had a favorable effect on the blow-blow mode and the PVP-2 productivity.

Table 3 (figure 3) presents the main indicators of the PVP-2 NMZ during the IPI.

Thus, the problem of involving non-ferrous raw materials of non-ferrous metals (sulfide ore concentrates, concentrates of technogenic deposits), characterized by a low sulfur content, and a decrease in the content of non-ferrous metals in the PVP slag, which increased the productivity of the process of suspended smelting, as well as reducing the likelihood of bedding in drugstore and slag bath PVP.

Claims (2)

1. A method of processing low-autogenous raw materials in a suspension smelting furnace, comprising supplying a metal-containing charge and flux in the form of a charge gas torch into the reaction zone of the said furnace with a stream of oxygen or oxygen enriched oxygen, melting the charge with the formation of matte and slag melts, separating the latter by settling, separate liquid output melting products and gases, characterized in that a carbon-containing reducing agent with a grain size of 3-15 mm in an amount of from 0.4 to 5 tons per hour in volume ratios with flux is introduced into the mixture t 1:30 to 1: 2. 2. The method according to p. 1, characterized in that as a carbon-containing reducing agent, coal or the products of its processing in the form of coke, semi-coke or coal lignite is introduced into the mixture.

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