CN111322869A - Smelting furnace and smelting method for continuous smelting of crude tin from tin concentrate and continuous fuming of slag - Google Patents

Abstract

A smelting furnace and a smelting method for continuous smelting of tin concentrate and continuous fumigation of crude tin and slag. The smelting furnace includes a front-end top-blown smelting furnace and a rear-end side-blown fumigation and depletion furnace with bottoms connected; the front-end top-blown smelting furnace The furnace includes a cylindrical furnace body (4), a material inlet (1) on the top of the furnace, a smelting lance (3) inserted from the top of the furnace, a smelting flue gas outlet (5) provided on the top of the furnace, and a rough gas outlet provided on the bottom of the furnace body. Tin discharge port (10); the side-blown smoke depletion furnace includes a rectangular box-type furnace body (18), a vulcanizing agent inlet (20) on the top of the furnace, and blowers symmetrically arranged on both sides of the lower part of the furnace body to blow into the furnace. The injection system (14) for injecting air and fuel, the lean slag discharge port (15) provided at the bottom of the furnace body, and the smoked flue gas outlet (19) provided at the top of the furnace body; the bottom of the rectangular box-type furnace body is Tilt the furnace floor (12). The invention can complete the two metallurgical processes of continuous smelting of tin concentrate into crude tin and smelting of tin-rich slag, continuous sulfurization, fuming and dilution in one step, with short process, low operating cost, high tin recovery rate and good energy-saving effect.

Description

Smelting furnace and smelting method for continuous smelting of crude tin from tin concentrate and continuous fuming of slag

technical field

The invention relates to the technical field of non-ferrous metal metallurgical equipment and methods, in particular to equipment and methods for pyrometallurgical smelting of tin concentrate and smoke and depletion of tin-rich slag.

Background technique

The method of smelting tin concentrate to produce crude tin is generally divided into two main smelting production process steps. The first step is to smelt the tin concentrate into crude tin and tin-rich slag, and the second step is to smoke and deplete the tin-rich slag. The tin is recovered and a lean slag is produced.

The traditional tin smelting process is to use blast furnace, reverberatory furnace, electric furnace, etc. to smelt tin concentrate to produce crude tin, and to produce tin-rich slag at the same time. The tin-rich slag of the smelting furnace is further depleted and depleted with a side-blown flue gasifier to recover tin soot. Blast furnace smelting belongs to backward production capacity and has been basically eliminated at present. Reverberatory furnaces and electric furnaces are still the most commonly used tin concentrate smelting equipment. They are characterized by simple process methods, small scale, high energy consumption, high labor intensity, many production links, serious environmental pollution, and high safety risks.

In the past 20 years, great progress has been made in the enhanced smelting of tin concentrates. The Ausmelt top-blown tin smelting furnace and the addition of oxygen enrichment have greatly improved the efficiency of tin smelting. Ausmelt furnace top blowing immersion smelting method belongs to the category of molten pool smelting, and has been widely used in the smelting of copper, tin, lead, steel, etc., and has developed rapidly in the past 20 years. The top blowing immersion smelting technology has the advantages of high smelting concentration, good furnace body sealing, good environmental protection conditions in the workshop, simple structure, simple material preparation, and relatively low investment. However, the disadvantage of this method is that the slag produced by smelting needs to be separately processed by the smoke furnace, which has many production links, complex processes and facilities, intermittent operation, low production efficiency, high energy consumption and low tin recovery rate.

At present, the tin-rich slag in tin smelting mainly uses the box-type side-blown flue gasifier sulfidation method to fume, volatilize, deplete and recover tin soot. The box-type side-blown fume furnace is also developing in the direction of large-scale, from the previous ^2.6m2 furnace type to the ^4m2 furnace type, and some manufacturers have already tried to use the 8m2 furnace type box ^- type side Smoke furnace. The main advantage of the box-type side-blown smoke furnace is that the volatilization efficiency of tin is high and the speed is fast. However, the main disadvantage is the intermittent operation. The slag generated by the smelting furnace needs to be added intermittently, and there are processes such as cooling, transportation, and heating. The process is long, the operation is complicated, the safety and environmental protection risks are high, and the energy consumption is high.

The above-mentioned equipment and method not only have complex equipment, small scale, large total investment, and complicated process, but also have a common problem, that is, the process of smelting tin concentrate into crude tin and tin-rich slag and tin-rich slag smoke is discontinuous, It takes several steps to complete the smelting of tin concentrate and the fume dilution of slag. The tin-rich slag must be cooled, transported, added to the fume furnace, and heated up between the smelting and fume processes. There are many production links, processes and facilities. Complex, intermittent operation, time-consuming, low production efficiency, high energy consumption, low tin metal recovery rate, high labor intensity, high safety and environmental pollution risks.

SUMMARY OF THE INVENTION

The object of the present invention is to solve the problems existing in the above-mentioned prior art, provide a kind of metallurgical process that can continuously complete the smelting of tin concentrate into thick tin and tin-rich slag, and smoke and depletion of tin-rich slag, and the equipment structure and The invention discloses a smelting furnace and a smelting method for continuous smelting of crude tin and slag for continuous smelting of tin concentrate with simple operation process, high tin metal recovery rate, low energy consumption, environmental protection and safety.

The object of the present invention is achieved through the following technical solutions:

A smelting furnace for continuous smelting of crude tin of tin concentrate and continuous fuming of slag, the smelting furnace is an integrated metallurgical furnace with front-end top-blowing smelting and rear-end side-blowing fuming, including a front-end top-blowing smelting furnace connected at the bottom and a rear-end side blown smoke depletion furnace; the front-end top-blown smelting furnace includes a cylindrical furnace body, a material inlet set on the top of the cylindrical furnace body, a smelting lance inserted into the furnace from the top of the cylindrical furnace body, and a smelting lance set on the cylindrical furnace body. The smelting flue gas outlet at the top of the cylindrical furnace body, and the coarse tin discharge outlet arranged at the bottom of the cylindrical furnace body; The inlet, the injection system for blowing air and fuel into the lean slag layer in the furnace symmetrically arranged on both sides of the lower part of the cuboid box furnace body, the lean slag discharge outlet arranged in the lower part of the cuboid box furnace body, and the The smoked flue gas outlet at the top of the furnace body; the lower part of the furnace chamber of the cylindrical furnace body of the front-end top-blown smelting furnace is communicated with the bottom of the furnace chamber of the rectangular box-type furnace body of the side-blown smoke and depletion furnace, and the furnace of the rectangular box-type furnace body is connected. The bottom is an inclined furnace bottom that slopes downward toward the cylindrical furnace body.

Further, the position of the inclined furnace bottom of the rectangular box-type furnace body is higher than the furnace bottom of the cylindrical furnace body.

The smelting method of the smelting furnace for continuous smelting of crude tin and slag from tin concentrate according to the present invention is to continuously reduce and smelt tin concentrate into crude tin and tin-rich slag in the same smelting furnace, and smelt tin-rich slag. The slag is continuously smoked and diluted to recover tin soot and continuously release the lean slag. The specific process is as follows: the tin concentrate smelting material is continuously added from the material inlet of the front-end top-blown smelting furnace to the position of the reducing smelting layer in the furnace, and the smelting lance is used to smelt the tin concentrate. Fuel, oxygen and compressed air are injected into the reduction smelting layer to stir the melt to realize the reduction smelting of the tin concentrate; after the reduction smelting, the tin oxide in the tin concentrate is reduced to coarse tin and settles at the bottom of the furnace to form a coarse tin layer. The crude tin discharge outlet is released from the top-blown smelting furnace; the smelting flue gas containing low concentration SO ₂ is discharged from the smelting flue gas outlet; the high-temperature liquid tin-rich slag layer produced by smelting floats on the crude tin layer and passes through the cylindrical furnace body The channel between the lower part of the furnace and the bottom of the cuboid box-type furnace body enters the side-blown smoke depletion furnace to form a lean slag layer. And the fuming reaction is carried out with the air and fuel injected from the injection system on both sides of the lower part of the cuboid box-type furnace body; the metal tin separated from the liquid slag sedimentation after reduction in the fuming and depletion furnace is along the inclination of the cuboid box-type furnace body. The bottom of the furnace flows into the coarse tin layer at the bottom of the cylindrical furnace body for collection; the tin-containing flue gas generated by the fuming reaction is discharged out of the furnace through the flue gas outlet, and the tin-depleted slag after fuming is continuously discharged out of the furnace through the lean slag discharge outlet. .

Further, the smelting flue gas containing low-concentration SO ₂ discharged from the flue gas outlet of the smelting area of the front-end top-blowing smelting furnace is processed by the waste heat boiler to recover waste heat and dust collector to recover tin fume, and the tail gas containing low-concentration SO ₂ is sent to The acid system produces sulfuric acid.

Further, after the tin-containing flue gas discharged from the flue gas outlet of the flue gas depletion zone of the side-blown flue gas depletion furnace, after the waste heat is recovered by the waste heat system and the tin dioxide flue dust is recovered by the dust collection system, the tail gas containing low concentration SO ₂ is sent to The acid system produces sulfuric acid.

Compared with other technological methods, the main advantages of the present invention are:

(1) The present invention only needs to use one metallurgical furnace to continuously complete two metallurgical processes of reducing and smelting tin concentrate into coarse tin and continuous fuming and depletion of slag, and can continuously smelt high-quality tin containing more than 90% in one step. Coarse tin, and make the tin-rich smelting slag containing about 5% tin flow directly and continuously smoke and deplete, and produce tin-rich soot with tin content of more than 45% and lean slag with tin content of less than 0.2%. The crude tin produced by the reduction in the process of internal sedimentation and fuming is merged into the smelting crude tin layer to be fully recovered, and the recovery rate of tin is high.

(2) The method of the present invention saves processes such as smelting furnace slag cooling, transportation, adding smoke furnace, heating, etc., the production links are few, the operation cost is low, the safety risk is small, the heat of the smelting tin-rich slag is fully utilized, and the residual heat of the flue gas is obtained. Fully utilized, low energy consumption and good energy saving effect.

(3) The method of the present invention has little fluctuation in the concentration of SO ₂ , and after the exhaust gas is absorbed (analyzed) by low concentration SO ₂ , continuous and stable acid production can be realized, the utilization rate of SO ₂ is greater than 98%, the environmental protection conditions are good, and the final exhaust gas can be discharged up to the standard .

(4) The device of the present invention is simple and reliable, and the manufacturing cost is low. In the process of the production method, the preparation of raw materials is simple, and the fumigation part does not need to prepare additional raw materials, which can greatly reduce production costs and improve product quality.

Description of drawings

Fig. 1 is the structural representation of the smelting furnace of the present invention;

Fig. 2 is the right side view of Fig. 1;

FIG. 3 is a plan view of FIG. 1 .

In the picture: 1-material inlet, 2-melting material, 3-melting lance, 4-cylindrical furnace body, 5-melting flue gas outlet, 6-reduction smelting layer, 7-separating furnace wall, 8-tin-rich slag layer , 9-coarse tin layer, 10-coarse tin discharge outlet, 11-integrated furnace bottom, 12-inclined furnace bottom, 13-smelting furnace outer wall, 14-injection system, 15-lean slag discharge outlet, 16-lean slag discharge Slag layer, 17- vulcanizing agent, 18- cuboid box furnace body, 19- fuming flue gas outlet, 20- vulcanizing agent adding port, 21- air coal bunker, 22- compressed air duct.

Detailed ways

As shown in Figure 1, Figure 2 and Figure 3, a smelting furnace for continuous smelting of tin concentrate and continuous fuming of slag, the smelting furnace is an integrated metallurgical system with front-end top-blown smelting and rear-end side-blown fuming. The furnace bottom of the integrated metallurgical furnace is an integrated furnace bottom 11 , and an outer wall 13 of the smelting furnace is built on the integrated furnace bottom 11 . The integrated metallurgical furnace includes a front-end top-blown smelting furnace and a rear-end side-blown smoke depletion furnace connected at the bottom.

The front-end top-blown smelting furnace includes a cylindrical furnace body 4, a material inlet 1 arranged on the top of the cylindrical furnace body, a smelting lance 3 inserted into the furnace from the top of the cylindrical furnace body, and a smelting flue gas arranged on the top of the cylindrical furnace body. Outlet 5, a coarse tin discharge outlet 10 arranged at the bottom of the cylindrical furnace body.

The side-blown smoke depletion furnace includes a cuboid box-type furnace body 18, a vulcanizing agent inlet 20 arranged on the top of the cuboid box-type furnace body, and a lean slag layer in the furnace opposite to the lower two sides of the cuboid box-type furnace body. 16 The injection system 14 for blowing air and fuel, the lean slag discharge outlet 15 arranged at the lower part of the cuboid box-type furnace body, and the fuming flue gas outlet 19 arranged at the top of the cuboid box-type furnace body. The injection system integrates a coal bunker 21 for storing fuel and a compressed air duct 22 . The rectangular box-type furnace body is convenient for furnace body masonry and maintenance.

The lower part of the furnace chamber of the cylindrical furnace body 4 of the front-end top-blown smelting furnace is communicated with the bottom of the furnace chamber of the cuboid box-type furnace body 18 of the side-blown smoke and depletion furnace, and the furnace bottom of the cuboid box-type furnace body is directed toward the cylindrical furnace body. Inclined furnace bottom 12 that slopes down. The inclined furnace bottom 12 of the rectangular box-type furnace body is positioned higher than the furnace bottom of the cylindrical furnace body. The cylindrical furnace body 4 and the upper part of the rectangular parallelepiped box furnace body 18 are separated by a partition furnace wall 7 .

The smelting method of the smelting furnace for continuous smelting of crude tin and slag for continuous fuming of tin concentrate according to the present invention no longer requires intermittently smelting tin concentrate through the smelting furnace, intermittently releasing crude tin and smelting tin-rich slag, and then smelting tin concentrate intermittently. The tin-rich slag is transferred to the fuming furnace for intermittent fuming and release of lean slag, but the tin concentrate is continuously reduced and smelted into coarse tin and tin-rich slag in the smelting area of the same smelting furnace, and the smelting tin-rich slag flows naturally to the smoke In the chemical reaction zone, continuous fume dilution is carried out, tin fume is recovered and lean slag is continuously released. The specific process is as follows: the smelting materials 2 such as tin concentrate, reducing agent and flux are continuously added from the material inlet 1 of the front-end top-blown smelting furnace to the position of the reducing smelting layer 6 in the smelting zone in the furnace, and the fuel, oxygen and The compressed air is injected into the reduction smelting layer 6 to stir the melt to realize the reduction smelting of the tin concentrate. After reduction smelting, the tin oxide in the tin concentrate is reduced to coarse tin and settles at the bottom of the furnace to form a coarse tin layer 9, which is discharged from the top-blown smelting furnace through the coarse tin discharge port 10. The smelting flue gas containing low concentration SO ₂ is discharged from the smelting flue gas outlet 5. After the waste heat is recovered by the waste heat system and the tin dioxide dust is recovered by the dust collection system, the tail gas containing low concentration SO ₂ is sent to the acid making system to produce sulfuric acid. The high-temperature liquid tin-rich slag produced by smelting floats on the thick tin layer 9 to form a tin-rich slag layer 8, and flows through the channel between the lower part of the furnace chamber of the cylindrical furnace body 4 and the furnace chamber bottom of the rectangular box-type furnace body 18, and automatically flows into the side blower. In the smoked and depleted furnace, a lean slag layer 16 is formed on the bottom of the side-blown smoked and depleted furnace. The vulcanizing agent 17 is added from the vulcanizing agent inlet 20, and will be mixed with the lean slag in the fuming and depleting furnace, and the vulcanization process smoke will be carried out with the air and fuel blown in from the injection system 14 on both sides of the lower part of the rectangular box-type furnace body. The high temperature liquid tin-rich slag is reduced, and the metal tin separated from the liquid slag sedimentation flows along the inclined bottom 12 of the cuboid box furnace body to the coarse tin layer 9 at the bottom of the cylindrical furnace body 4 for collection. The tin-containing flue gas produced by the fuming reaction is discharged out of the furnace through the fumed flue gas outlet 19. After the waste heat recovery, the oxidation of the flue dust and the recovery of the tin flue dust, the tail gas containing low concentration SO ₂ is passed through the acid system to produce sulfuric acid. The fumed tin-depleted slag is continuously discharged out of the furnace through the lean slag discharge port 15 . The furnace bottom of the rectangular box-type furnace body is set to be inclined, and the inclined furnace bottom 12 is located higher than the furnace bottom of the cylindrical furnace body, which can ensure that the high-temperature liquid tin-rich slag layer 8 produced by the front-end top-blowing melting furnace can automatically flow into the side-blowing furnace. The smoked and depleted furnace, and the metal tin separated from the liquid slag sedimentation after reduction in the side-blown smoked and depleted furnace can automatically flow back to the bottom of the front-end top-blown smelting furnace to be discharged.

The device and method of the invention can continuously complete two metallurgical processes of reducing and smelting tin concentrate into crude tin and continuous fuming and depletion of slag with only one metallurgical furnace, continuously smelting high-quality crude tin in one step, and making tin The smelting slag is directly flowed and continuously smoked and diluted, which saves the process of smelting furnace slag cooling, transportation, adding to the smoke furnace, heating and other processes, with fewer production links and low operating costs. The crude tin produced by the reduction of liquid slag in the furnace sedimentation and fuming process is also fully recovered, and the recovery rate of tin is high; the heat of smelting tin-rich slag is fully utilized, and the energy saving effect is good.

Claims (5)

1. the smelting furnace of continuous smelting of tin concentrate and continuous fuming of crude tin and slag, it is characterized in that, described smelting furnace is the one-piece metallurgical furnace of front-end top-blown smelting and rear-end side-blown fuming, including the front end communicated with the bottom A top-blown smelting furnace and a rear-end side-blown smoke depletion furnace; the front-end top-blown smelting furnace includes a cylindrical furnace body (4), a material inlet (1) arranged on the top of the cylindrical furnace body, and a A smelting lance (3) whose top is inserted into the furnace, a smelting flue gas outlet (5) arranged at the top of the cylindrical furnace body, and a coarse tin discharge outlet (10) arranged at the bottom of the cylindrical furnace body; the side blowing smoke is depleted The furnace comprises a cuboid box-type furnace body (18), a vulcanizing agent feeding port (20) disposed on the top of the cuboid box-type furnace body, and a lean slag layer (16) in the furnace disposed on both sides of the lower part of the cuboid box-type furnace body for blowing into the furnace An air and fuel injection system (14), a lean slag discharge outlet (15) arranged at the lower part of the cuboid box-type furnace body, and a flue gas outlet (19) arranged at the top of the cuboid box-type furnace body; The lower part of the furnace chamber of the cylindrical furnace body (4) of the blowing smelting furnace is communicated with the bottom of the furnace chamber of the cuboid box-type furnace body (18) of the side-blown fume depletion furnace, and the furnace bottom of the cuboid box-type furnace body is directed toward the cylindrical furnace body Down-sloping inclined furnace bottom (12). 2. The smelting furnace for continuous smelting of crude tin from tin concentrate and continuous fuming of slag according to claim 1, characterized in that the position of the inclined furnace bottom (12) of the cuboid box furnace body is higher than that of the cylindrical furnace body bottom of the furnace. 3. the smelting method of the smelting furnace of tin concentrate continuous smelting thick tin and slag continuous fuming as claimed in claim 1 and 2, it is characterized in that, smelting method is to continuously reduce smelting tin concentrate in the same smelting furnace Coarse tin and tin-rich slag are formed, and the smelting tin-rich slag is continuously smoked and depleted to recover tin soot and continuously release the lean slag. The inlet (1) is continuously added to the position of the reducing smelting layer (6) in the furnace, and the fuel, oxygen and compressed air are sprayed into the reducing smelting layer (6) through the smelting lance (3), and the melt is stirred to realize the tin concentrate. Reduction smelting; after reduction smelting, the tin oxide in the tin concentrate is reduced to coarse tin and settles at the bottom of the furnace to form a coarse tin layer (9), which is discharged from the top-blown smelting furnace through the coarse tin discharge port (10); contains low concentration The smelting flue gas of SO ₂ is discharged from the smelting flue gas outlet (5); the high-temperature liquid tin-rich slag layer (8) produced by smelting floats on the coarse tin layer (9), and passes through the lower part of the furnace chamber of the cylindrical furnace body (4) and The channel between the bottoms of the furnace chambers of the rectangular box-type furnace body (18) enters the side-blown smoke depletion furnace to form a lean slag layer (16), which is added to the smoke depletion furnace and from the vulcanizing agent inlet (20). The vulcanizing agent (17) is mixed with the air and fuel blown in from the lower two sides of the cuboid box furnace body and the air and fuel are subjected to a fuming reaction; The metal tin flows along the inclined furnace bottom (12) of the cuboid box-type furnace body to the coarse tin layer (9) at the bottom of the cylindrical furnace body (4) for collection; The outlet (19) is discharged out of the furnace, and the fumed tin-depleted slag is continuously discharged out of the furnace through the lean slag discharge outlet (15). 4. the smelting method of the smelting furnace of tin concentrate continuous smelting thick tin and slag continuous fuming according to claim 3, it is characterized in that, from the smelting zone flue gas outlet (5) of the front-end top-blown smelting furnace, the smelting area containing the The smelting flue gas with low concentration SO ₂ is treated by waste heat boiler to recover waste heat and dust collector to recover tin fume, and then the tail gas containing low concentration SO ₂ is sent to the acid making system to produce sulfuric acid. 5. the smelting method of the smelting furnace of tin concentrate continuous smelting thick tin and slag continuous fuming according to claim 3 or 4, it is characterized in that, from the fuming zone flue gas outlet ( 19) After the exhausted tin-containing flue gas is recovered by the waste heat system and the tin dioxide dust is recovered by the dust collection system, the tail gas containing low concentration SO ₂ is sent to the acid-making system to produce sulfuric acid.

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