CN105671326A - Stirring synergy method for diluting copper slag with injection gas carrying vulcanizing agent - Google Patents

Abstract

The invention provides a method for stirring and cooperating with injection gas to carry vulcanizing agent to deplete copper slag. The process steps are: (1) Introduce eccentric mechanical stirring equipment into the depletion furnace, and introduce high-temperature molten copper slag at 1150~1350°C In the depletion furnace, adjust the stirring blade to extend to 1/3 to 1/2 of the height of the copper slag liquid level, start heating and stirring, control the temperature of the copper slag to 1150-1350°C, and the stirring speed to 50-200r/min ; (2) Install a ventilator at the bottom or side of the depletion furnace for blowing the vulcanizing agent carrier gas, and blow the vulcanizing agent into the molten copper slag through the bottom blowing or side blowing of the venting brick through the carrier gas to control the blowing The pressure is 0.1~1.5MPa, the injection flow rate is 5~60m ³ /h, the amount of vulcanizing agent added is 0.3~8% of the copper slag mass, the mixture is injected and stirred for 10~60min; (3) Static layering, respectively collecting the lower layer of matte and the upper layer of depleted slag.

Description

A method for stirring and cooperating with injection gas to carry vulcanizing agent to deplete copper slag

technical field

The invention belongs to the technical field of metallurgy, and in particular relates to a method for stirring and cooperating with injection gas to carry vulcanizing agent to deplete copper slag.

Background technique

With the continuous development of copper smelting technology, the smelting intensity and the taste of copper matte have been continuously improved, and the copper content of the primary smelting slag has also been continuously increased. Copper is sometimes as high as 3-4%, well above the current 0.3% copper mining grade.

At present, the production of 1 ton of copper produces 2.2 tons of copper slag, and the cumulative stockpiling of copper slag in my country has reached about 250 million tons. In 2014, the output of refined copper in my country was 7.96 million tons, and the output of copper slag can be approximately calculated to be about 15 million tons. Bulk waste, to a certain extent, has caused an unrecoverable impact on the ecological environment, and the annual economic loss due to the waste of heat emitted by copper slag is more than 200 million yuan.

There are two types of copper slag dilution methods in industry: slow cooling mineral processing method and pyrolysis method. The copper recovery rate of the beneficiation method is high, and the energy consumption is low, but the waste heat in the slow cooling process of hot copper slag is not recycled, resulting in huge energy waste. Requirements limit the use of small and medium-sized enterprises, and the process requires a lot of water and has low environmental benefits. Pyrochemical depletion directly depletes the hot slag by electric heating. At present, the copper content in the waste slag after being separated and depleted by the electric furnace is generally above 0.6%, and the copper content in the waste slag is still relatively high. The main problem is that the vulcanizing agent is added to the furnace. Inside, floating on the surface of the molten pool, except for the burnt part, it can only rely on the "sliding contact" on the surface of the slag to carry out the chemical reaction process. The kinetic conditions of this "sliding contact" result in low depletion efficiency.

The patent with application number 201310311055.X discloses a method and a depletion device for copper smelting molten slag depletion. Although the injection of inert gas to stir the melt has improved the contact process between the vulcanizing agent and the copper slag to a certain extent, but the top feeding method has not fundamentally solved the problem that the vulcanizing agent floats on the surface of the slag after adding, and the contact with the melt Difficulty mixing well.

The patent with the application number 200910088879.9 also proposes an electrothermal depletion process for copper smelting slag. In this patent, the vulcanizing agent is also added through the feeding port on the top of the furnace shell, and the sufficient mixing of the vulcanizing agent and copper smelting slag and Reaction problems, low utilization efficiency of vulcanizing agents and serious environmental pollution.

The patent with the application number 201510261859.2 proposes a copper smelting slag treatment device and its method. In this patent, the vulcanizing agent is added from the feeding port on the top of the furnace body, and the method also introduces a reducing agent, which is added from the auxiliary material feeding port on the top of the furnace body. On the bottom and side walls of the furnace body, natural gas and oxygen are sprayed into the furnace to stir the melt, and the melt is stirred solely by the injection power of natural gas and oxygen. The vulcanizing agent floats on the surface of the melt, and it is difficult to fully mix and react with the copper slag melt, resulting in a low utilization rate of the two. In order to achieve the effect of fully removing copper, a large amount is often used; Toxic and harmful gases will be produced, the pollution is relatively large, and there may be an explosion hazard after mixing with oxygen. Therefore, a new method of depleting copper slag is urgently needed to overcome the above shortcomings, completely change the way of adding vulcanizing agent, effectively improve the utilization rate of vulcanizing agent, reduce the copper content in tailing slag, improve the depletion level of copper smelting slag, and improve the on-site environment .

Contents of the invention

Aiming at the problems existing in the prior art, the present invention proposes a method of stirring and cooperating with injection gas to carry vulcanizing agent depleted copper slag, introducing stirring equipment into molten copper smelting slag depletion furnace, and then injecting vulcanizing agent through the injection gas Carried into the copper slag, the vulcanizing agent is fully mixed with the slag under the double action of mechanical stirring and gas injection. Technical scheme of the present invention is:

A method for stirring and co-injecting gas to carry vulcanizing agent to deplete copper slag is carried out according to the following steps:

(1) Introduce eccentric mechanical stirring equipment into the depletion furnace, introduce high-temperature molten copper slag at 1150~1350°C into the depletion furnace, and adjust the stirring blade to reach 1/3 to 1/2 of the height of the copper slag liquid level , turn on heating and stirring, control the temperature of the copper slag to 1150-1350°C, and the stirring speed to 50-200r/min;

(2) At the bottom or side of the depletion furnace, a ventilator for blowing the carrier gas of the vulcanizing agent is installed, and the vulcanizing agent is blown into the molten copper slag through the bottom blowing or side blowing of the venting brick through the carrier gas to control the injection pressure 0.1~1.5MPa, the injection flow rate is 5~60m ³ /h, the amount of vulcanizing agent added is 0.3~8% of the copper slag mass, the mixture is injected and stirred for 10~60min;

(3) Static layering, respectively collecting the lower layer of matte and the upper layer of depleted slag.

In the above method, the carrier gas is natural gas, inert gas or nitrogen.

In the above method, the vulcanizing agent includes copper concentrate or pyrite.

In the above method, the grade of matte in the lower layer is about 70%, and the copper content in the slag after the upper layer is depleted is 0.3% or less.

In the above method, the high-temperature flue gas generated during the depletion process of copper smelting slag is recovered by the boiler and cyclone dust removal, and the volatile and valuable components of zinc, lead, molybdenum and arsenic in the flue gas are recovered, and finally the flue gas is removed by the washing device The sulfur dioxide gas contained in the tank will be discharged into the atmosphere after meeting the emptying requirements.

In the above method, when the carrier gas is inert gas or nitrogen, the vulcanizing agent is sprayed into the slag through the air _- permeable brick, and FeS reacts with _Fe3O4 and _SiO2 to form 2FeO· _SiO2 , which reduces the viscosity of the slag, and the vulcanizing agent and Cu ₂ O reacts to generate Cu ₂ S to recover the chemically dissolved copper in the copper slag. The reaction equations involved are as follows:

Cu2O ₊ FeS=Cu2S ₊ FeO

3Fe ₃ O ₄ +FeS+5SiO ₂ =5(2FeO∙SiO ₂ )+SO ₂

In the above method, when the carrier gas is natural gas, the natural gas is pyrolyzed to generate C and H ₂ , and Fe ₃ O ₄ is reduced to FeO to form silicate with SiO ₂ ; at the same time, the vulcanizing agent reacts with Cu ₂ O in the slag to form Cu ₂ S forms copper matte and reacts with Fe ₃ O ₄ and SiO ₂ to form 2FeO∙SiO ₂ . The reaction equations involved are as follows:

Fe ₃ O ₄ +1/3CH ₄ (g)=3FeO+2/3H ₂ O(g)+1/3CO(g)

Fe ₃ O ₄ +1/4CH ₄ (g)=3FeO+1/4CO ₂ (g)+1/2H ₂ O(g)

Fe ₃ O ₄ +CO(g)=3FeO+CO ₂ (g)

CH ₄ (g) = C + 2H ₂ (g)

Fe ₃ O ₄ +C=3FeO+CO(g)

Fe ₃ O4+1/2C=3FeO+1/2CO ₂ (g)

Fe ₃ O ₄ +H ₂ (g)=3FeO+H ₂ O(g)

Cu2O ₊ FeS=Cu2S ₊ FeO

2FeO+SiO ₂ =2FeO∙SiO ₂

3Fe ₃ O ₄ +FeS+5SiO ₂ =5(2FeO∙SiO ₂ )+SO ₂

Compared with the existing copper slag depletion technology, the characteristics and beneficial effects of the present invention are: the present invention sets eccentric stirring equipment in the depletion furnace, and adopts the method of injecting gas to carry vulcanizing agent into the molten copper slag system, Under the dual action of mechanical stirring and gas injection, the vulcanizing agent and molten slag are fully mixed and contacted to react, optimizing the dynamic conditions of the vulcanizing agent reaction and effectively inhibiting the formation of foamy slag, avoiding the rise of the molten slag level and splashing phenomenon, the method of the present invention can make the utilization rate of the vulcanizing agent reach more than 80%, and the copper content in the slag after depletion reaches below 0.3%. In addition, the present invention has high safety, and the tail gas generation is low and all are recycled. The environmental pollution is extremely low, and it has great economic and environmental benefits.

Description of drawings:

Fig. 1 is the schematic structural view of the depletion furnace adopted in the method for depleting copper slag with sulfide carried by the injection gas of Embodiment 1 and Embodiment 3 of the present invention;

Fig. 2 is the schematic structural view of the depletion furnace adopted in the method for depleting copper slag with sulfide carried by the injection gas in Embodiment 2 and Embodiment 4 of the present invention;

Among them: 1-slag discharge port, 2-matte copper discharge port, 3-stirring paddle, 4-stirring paddle lifting system, 5-copper slag chute, 6-natural gas bottom blowing injection port, 7-natural gas side blowing injection port, 8 -Cyclone dust removal system, 9-waste heat recovery system, 10-scrubbing tower.

detailed description

The depletion furnace used in the embodiment of the present invention is self-made equipment.

The copper slag used in Examples 1 and 2 of the present invention is oxygen-enriched bottom-blown copper smelting slag, and its specific composition is shown in Table 1.

Table 1 Multi-element analysis results of copper smelting slag used in Examples 1 and 2 (mass fraction, %)

components T _Fe FeO Cu Zn S Al ₂ O ₃ CaO MgO SiO ₂ Au g/t As content 42.47 43.14 4.51 5.67 1.55 3.02 0.96 1.09 20.82 1.2 0.075

The copper smelting slag used in Examples 3 and 4 of the present invention is oxygen-enriched bottom-blown copper smelting slag, and its specific composition is shown in Table 2;

Table 2 Multi-element analysis results of copper smelting slag used in Examples 3 and 4 (mass fraction, %)

components T _Fe FeO Cu Zn S Al ₂ O ₃ CaO MgO SiO ₂ As content 45.50 45.99 2.36 1.67 0.86 3.35 0.74 0.74 27.54 0.018

Example 1

The amount of molten copper slag is 1 ton, and the composition is shown in Table 1. The depletion furnace used is shown in Figure 1. The depletion treatment method is carried out according to the following process steps:

(1) Introduce eccentric mechanical stirring equipment into the depletion furnace, introduce high-temperature molten copper slag at 1150~1350°C into the depletion furnace, adjust the stirring blade to extend to 1/2 of the height of the copper slag liquid level, and turn on the heating and stirring, the temperature of the copper slag is controlled to be 1280°C, and the stirring speed is 90r/min;

(2) At the bottom of the depletion furnace, a ventilating rotor for injecting carrier gas carrying sulfide is installed to highly disperse 30kg of copper concentrate and 20kg of calcium oxide powder, and inject natural gas to carry copper concentrate and calcium oxide powder through The bottom of the breathable brick is blown into the molten copper slag, the injection pressure is controlled at 0.2MPa, the injection flow rate is 18m ³ /h, the mixture is injected and eccentrically stirred for 30 minutes;

(3) Static layering, collecting the lower layer of matte and the upper layer of depleted slag, in which the depleted slag contains 0.3% copper, 1.43% Fe ₃ O ₄ , and the grade of copper matte is %(Cu)68.

The high-temperature flue gas produced during the depletion process of copper smelting slag passes through the boiler to recover waste heat and cyclone dust removal, recovers the volatile and valuable components of zinc, lead, molybdenum and arsenic in the flue gas, and finally removes the volatile components contained in the flue gas through the washing device. Sulfur dioxide gas is discharged into the atmosphere after meeting the emptying requirements.

Example 2

The amount of molten copper slag is 1 ton, and the composition is shown in Table 1. The depletion furnace used is shown in Figure 2. The depletion treatment method is carried out according to the following process steps:

(1) Introduce eccentric mechanical stirring equipment into the depletion furnace, introduce high-temperature molten copper slag at 1150~1350°C into the depletion furnace, adjust the stirring blade to extend to 1/3 of the height of the copper slag liquid level, and turn on the heating and stirring, the temperature of the copper slag is controlled to be 1300°C, and the stirring speed is 85r/min;

(2) On the side of the depletion furnace, a ventilating rotor for injecting carrier gas carrying vulcanizing agent is installed to highly disperse 36kg pyrite and 25kg calcium oxide powder, and inject natural gas to carry pyrite and calcium oxide powder Blow into the molten copper slag through the side of the ventilation brick, control the injection pressure to 0.6MPa, the injection flow rate to 15m ³ /h, inject the mixture and react with eccentric stirring for 40min;

(3) Static stratification, collecting the lower layer of matte and the upper layer of depleted slag, in which the depleted slag contains 0.29% copper, 1.52% Fe ₃ O ₄ , matte grade %(Cu)70.

The high-temperature flue gas produced during the depletion process of copper smelting slag passes through the boiler to recover waste heat and cyclone dust removal, recovers the volatile and valuable components of zinc, lead, molybdenum and arsenic in the flue gas, and finally removes the volatile components contained in the flue gas through the washing device. Sulfur dioxide gas is discharged into the atmosphere after meeting the emptying requirements.

Example 3

The amount of molten copper slag is 1 ton, and the composition is shown in Table 1. The depletion furnace used is shown in Figure 1. The depletion treatment method is carried out according to the following process steps:

(1) Introduce eccentric mechanical stirring equipment into the depletion furnace, introduce high-temperature molten copper slag at 1150~1350°C into the depletion furnace, adjust the stirring blade to extend to 1/3 of the height of the copper slag liquid level, and turn on the heating and stirring, the temperature of the copper slag is controlled to be 1300°C, and the stirring speed is 80r/min;

(2) At the bottom of the depletion furnace, a ventilating rotor for injecting carrier gas carrying a vulcanizing agent is installed to highly disperse 17kg pyrite and 15kg calcium oxide powder, and inject natural gas to carry pyrite and calcium oxide powder through The bottom of the breathable brick is blown into the molten copper slag, the injection pressure is controlled at 0.8MPa, the injection flow rate is 5m ³ /h, the mixture is injected and eccentrically stirred for 40 minutes;

(3) Static layering, collecting the lower layer of matte and the upper layer of depleted slag, in which the copper content of the depleted slag is 0.26%, the content of Fe ₃ O ₄ is 1.64%, and the grade of matte copper is %(Cu)71.

The high-temperature flue gas produced during the depletion process of copper smelting slag passes through the boiler to recover waste heat and cyclone dust removal, recovers the volatile and valuable components of zinc, lead, molybdenum and arsenic in the flue gas, and finally removes the volatile components contained in the flue gas through the washing device. Sulfur dioxide gas is discharged into the atmosphere after meeting the emptying requirements.

Example 4

The amount of molten copper slag is 1 ton, and the composition is shown in Table 1. The depletion furnace used is shown in Figure 2. The depletion treatment method is carried out according to the following process steps:

(1) Introduce eccentric mechanical stirring equipment into the depletion furnace, introduce high-temperature molten copper slag at 1150~1350°C into the depletion furnace, adjust the stirring blade to extend to 1/3 of the height of the copper slag liquid level, and turn on the heating and stirring, the temperature of the copper slag is controlled to be 1300°C, and the stirring speed is 90r/min;

(2) On the side of the depletion furnace, a ventilating rotor for injecting carrier gas carrying vulcanizing agent is installed to highly disperse 25kg pyrite and 20kg calcium oxide powder, and inject natural gas to carry pyrite and calcium oxide powder Blow into the molten copper slag through the side of the ventilation brick, control the injection pressure to 1.0MPa, the injection flow rate to 30m ³ /h, inject the mixture and react with eccentric stirring for 20min;

(3) Static layering, collecting the lower layer of matte and the upper layer of depleted slag, in which the depleted slag contains 0.27% copper, 1.58% Fe ₃ O ₄ , and the grade of copper matte is %(Cu)68.

The high-temperature flue gas produced during the depletion process of copper smelting slag passes through the boiler to recover waste heat and cyclone dust removal, recovers the volatile and valuable components of zinc, lead, molybdenum and arsenic in the flue gas, and finally removes the volatile components contained in the flue gas through the washing device. Sulfur dioxide gas is discharged into the atmosphere after meeting the emptying requirements.

Claims (4)

1. a method for stirring and cooperating injection gas to carry vulcanizing agent to deplete copper slag is characterized in that it is carried out according to the following steps: (1) Introduce eccentric mechanical stirring equipment into the depletion furnace, introduce high-temperature molten copper slag at 1150~1350°C into the depletion furnace, and adjust the stirring blade to reach 1/3 to 1/2 of the height of the copper slag liquid level , turn on heating and stirring, control the temperature of the copper slag to 1150-1350°C, and the stirring speed to 50-200r/min; (2) At the bottom or side of the depletion furnace, a ventilator for blowing the carrier gas of the vulcanizing agent is installed, and the vulcanizing agent is blown into the molten copper slag through the bottom blowing or side blowing of the venting brick through the carrier gas to control the injection pressure 0.1~1.5MPa, the injection flow rate is 5~60m ³ /h, the amount of vulcanizing agent added is 0.3~8% of the copper slag mass, the mixture is injected and stirred for 10~60min; (3) Static layering, respectively collecting the lower layer of matte and the upper layer of depleted slag. 2. A method for stirring and co-injecting gas to carry vulcanizing agent depleted copper slag according to claim 1, characterized in that in the above method, the carrier gas is natural gas, inert gas or nitrogen. 3. A method for agitating and co-injecting gas to carry vulcanizing agent to deplete copper slag according to claim 1, characterized in that said vulcanizing agent comprises copper concentrate or pyrite. 4. A method for agitating and cooperating with injecting gas to carry vulcanizing agent to deplete copper slag according to claim 1, characterized in that the copper content in the depleted upper layer slag is 0.3% or less.