Electric furnace for integrally reducing and separating multiple metals of lead, zinc and iron in slag

Abstract

The utility model discloses an electric furnace for integrally reducing and separating multiple metals of lead, zinc and iron in slag, which comprises a furnace body, the furnace body is provided with a slag inlet and a slag outlet, and the inner cavity of the furnace body is divided into a lead reducing and separating area, a zinc reducing and separating area and an iron reducing and separating area along the flowing direction of the slag; electrode holes and feeding holes are formed in the top of the furnace body corresponding to the lead reduction separation area, the zinc reduction separation area and the iron reduction separation area; the furnace body is provided with a lead liquid siphon discharge port in the lead reduction separation area, a zinc flue gas discharge port in the furnace body, and an iron liquid discharge port in the iron reduction separation area in the furnace body; a plasma gun is installed on the side wall of the furnace body, and the installation height position of the plasma gun is the height position of the slag surface. According to the utility model, lead, zinc and iron are reduced and separated in one furnace body, different temperature ranges are controlled for each functional area according to the boiling point of metal, unnecessary energy consumption is reduced, and the speed and efficiency of reduction reaction are improved by adopting a mode of combined action of the electrode and plasma electric action and the reducing agent.

Description

An integrated electric furnace for reducing and separating lead, zinc, iron, and polymetallic metals from molten slag. Technical Field

[0001] This utility model belongs to the field of non-ferrous metal metallurgy technology, specifically relating to an electric furnace for integrated reduction and separation of lead, zinc, iron and polymetallic metals in molten slag. Background Technology

[0002] In my country's non-ferrous metallurgy, lead and zinc smelting are mainly carried out separately, with iron entering the slag and being stored as large amounts of solid and hazardous waste. Lead smelting is mainly a pyrometallurgical process, which primarily uses a three-furnace unit consisting of oxidation smelting, direct reduction of liquid slag, and zinc extraction via fuming. The byproduct zinc is mainly recovered and enriched in the fuming furnace to obtain low-value zinc oxide, which is then used in the zinc hydrometallurgical process to obtain metallic zinc. Zinc smelting is mainly a hydrometallurgical process, primarily using a series of units for sulfuric acid leaching, purification, and electrowinning. Currently, only the ISP lead-zinc co-metallurgical process exists for lead-zinc co-metallurgy.

[0003] Currently, there are technologies for recovering lead, zinc, and iron polymetallic metals using electric furnaces, but the low operating efficiency is due to insufficient reaction power during the smelting process. In summary, current stepwise or mixed smelting methods for lead and zinc suffer from varying degrees of problems, including long processes, high energy consumption, low operating efficiency, low metal recovery rates, and failure to recover iron at high value. Summary of the Invention

[0004] This invention provides an integrated electric furnace for reducing and separating lead, zinc, iron, and polymetallic metals in molten slag, thereby addressing the shortcomings described in the prior art.

[0005] The technical solution adopted in this utility model is as follows:

[0006] An integrated electric furnace for reducing and separating lead, zinc, and iron polymetallic slag includes a furnace body with a slag inlet and a slag outlet. The furnace body's inner cavity is divided into a lead reduction and separation zone, a zinc reduction and separation zone, and an iron reduction and separation zone along the slag flow direction. Electrode holes and charging ports are provided on the top of the furnace body corresponding to each of the lead, zinc, and iron reduction and separation zones. The furnace body has a lead molten metal siphon outlet in the lead reduction and separation zone, a zinc flue gas outlet in the zinc reduction and separation zone, and an iron molten metal outlet in the iron reduction and separation zone. The slag inlet receives the high-temperature oxidized slag flow generated from the upstream smelting process and introduces it into the furnace body. Dividing the furnace body's inner cavity into three functional zones allows for the reduction and separation of lead, zinc, and iron within a single furnace, unlike the cumbersome process of multiple independent steps in traditional smelting. The charging ports facilitate the uniform and rapid addition of reducing agents and their reaction with metal oxides to reduce the metals. The lead liquid siphon outlet can be set on the front end wall of the furnace body or on the side wall of the lead reduction separation zone of the furnace body near the front end wall of the furnace body. The specific location is set according to actual needs. The zinc flue gas outlet is preferably set on the side wall of the furnace body in the zinc reduction separation zone, but it can also be set on the rear end wall at the slag outlet of the furnace body.

[0007] In a preferred embodiment of this invention, an electrode is installed at the electrode hole, with the tip of the electrode inserted below the surface of the molten slag to a depth of 200mm to 500mm. Each functional zone uses an electrode to control a different temperature range based on the boiling point of the metal to be reduced, thereby reducing unnecessary energy consumption.

[0008] As a preferred embodiment of this utility model, the electrode is installed in a liftable manner at the electrode hole.

[0009] As a preferred embodiment of this utility model, the temperature of the lead reduction separation zone is 1000℃~1200℃; the temperature of the zinc reduction separation zone 5 is 1200℃~1350℃; and the temperature of the iron reduction separation zone is 1350℃~1550℃.

[0010] As a preferred embodiment of this utility model, the bottom surface of the furnace body corresponding to the zinc reduction separation zone is the highest.

[0011] As a preferred embodiment of this utility model, the feeding port includes a coke particle feeding port and an additive feeding port for adding lime or silica.

[0012] In a preferred embodiment of this invention, the lead liquid siphon outlet and the slag inlet are located in the lead reduction separation zone, with the slag inlet located above the lead liquid siphon outlet; the slag outlet is located in the iron reduction separation zone. The lead liquid siphon outlet and the slag inlet are preferably located on the front end wall of the furnace body. The location of the slag inlet is not limited to the front end wall of the furnace body; it can be located on the side wall or the top of the furnace body, depending on actual needs. The slag outlet can be located on the rear end wall of the furnace body or on the side wall of the furnace body.

[0013] In a preferred embodiment of this invention, plasma guns are installed on both sides of the furnace body corresponding to the lead reduction separation zone, zinc reduction separation zone, and iron reduction separation zone. The head of the plasma gun is inserted at an angle below the molten slag surface, and the installation position of the plasma gun is level with the slag surface and tilted downwards from the outside to the inside. High-temperature, high-energy plasma is generated by the plasma guns, enhancing the reduction capability and reducing the energy required in traditional smelting processes.

[0014] As a preferred embodiment of this utility model, the head of the plasma gun is inserted below the surface of the molten slag, and the insertion depth of the plasma gun head is 50mm to 200mm.

[0015] As a preferred embodiment of this invention, N2 gas or CO gas carrying reducing agent powder is introduced into the plasma gun.

[0016] This invention, in the lead reduction and separation zone, captures gold and silver precious metals as the lead liquid descends, improving the recovery rate of precious metals. In the iron reduction and separation zone, iron is separated from the oxide slag through high-temperature reduction and deposited at the bottom of the furnace as molten metal, achieving high-value recovery of iron. Zinc is collected as zinc-containing flue gas after being discharged from the furnace. The reduction and separation processes of lead, zinc, and iron are completed in one furnace, reducing the cumbersome process of multiple independent steps in traditional smelting. Furthermore, by controlling different temperature ranges for each functional zone according to the boiling point of the metal, unnecessary energy consumption is reduced. High-temperature, high-energy plasma is generated by a plasma gun to enhance the reduction capability, further reducing the energy required in traditional smelting processes. By employing the combined action of electrodes, plasma electro-action, and reducing agents, the speed and efficiency of the reduction reaction are improved. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 is a front view of this utility model.

[0019] Figure 2 is a cross-sectional view along the BB direction in Figure 1 with the electrodes omitted.

[0020] Figure 3 is a top view of this utility model.

[0021] Figure 4 is a sectional view along line AA in Figure 3. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Example 1:

[0024] An integrated electric furnace for reducing and separating lead, zinc, iron and polymetallic slag, as shown in Figures 1, 3 and 4, includes a furnace body 1. The furnace body 1 is provided with a slag inlet 2 and a slag outlet 3. In this embodiment, the furnace body 1 is in the shape of a cuboid, and the side walls and end walls are connected by an arc. Of course, the furnace body can also adopt other structural forms and is not limited to the shape given in this embodiment.

[0025] As shown in Figures 1 and 4, the inner cavity of the furnace body 1 is divided into a lead reduction separation zone 4, a zinc reduction separation zone 5, and an iron reduction separation zone 6 along the slag flow direction.

[0026] The top of the furnace body 1 corresponding to lead reduction separation zone 4, zinc reduction separation zone 5 and iron reduction separation zone 6 is provided with electrode holes 7 and feeding ports 8; as shown in Figures 1, 3 and 4, the feeding ports are mainly used to add solid reducing agents and metallurgical additives. The feeding ports are coke particle feeding ports and additive feeding ports for adding lime or silica.

[0027] An electrode 12 is installed at each electrode hole 7. Preferably, the electrode is installed in a liftable manner at the electrode hole. The liftable installation can be achieved by using a lifting device in the prior art, which is not shown in this embodiment. However, a clamping structure is provided on the electrode 12 above the copper clip 14. The clamping structure is used to connect with the lifting device. During operation, the position of the electrode is adjusted by using the lifting device so that the head of the electrode 12 is inserted into the molten slag at a depth of 200mm to 500mm below the surface. The specific insertion depth is adjusted according to the actual situation.

[0028] Electrode 12 is connected to an external power source via copper clip 14. The external power source supplies power to the electrode through the copper clip to make it heat up.

[0029] Because lead, zinc, and iron have different boiling points, each functional zone uses electrodes to control different temperature ranges based on the required reduction temperature and the difference in boiling points between the metals, in order to reduce unnecessary energy consumption; the temperature of lead reduction separation zone 4 is controlled at 1000℃~1200℃; the temperature of zinc reduction separation zone 5 is controlled at 1200℃~1350℃; and the temperature of iron reduction separation zone 6 is controlled at 1350℃~1550℃.

[0030] The furnace body 1 has a lead liquid siphon outlet 9 in the lead reduction separation zone 4. The lead liquid siphon outlet 9 and the slag inlet 2 are located on the same side of the lead reduction separation zone 4. In this embodiment, both are located on the end wall of the furnace body, and the slag inlet 2 is located above the lead liquid siphon outlet 9. Of course, the location of the lead liquid siphon outlet 9 is not limited to the front end wall of the furnace body, but can also be located on the side wall of the furnace body near the front end wall. The location of the slag inlet is not limited to the front end wall of the furnace body, but can be located on the side wall or the top of the furnace body.

[0031] The furnace body 1 has a zinc flue gas outlet 10 in the zinc reduction separation zone 5, as shown in Figure 2. Because zinc has a low boiling point of only 907℃, zinc is mainly discharged from the zinc flue gas outlet 10 in the form of zinc-containing flue gas. The zinc flue gas outlet 10 can also be located at the rear end of the furnace body, as long as it can discharge zinc flue gas.

[0032] The furnace body 1 has an iron molten outlet 11 in the iron reduction separation zone 6, as shown in Figures 1 and 2. The iron molten outlet 11 is located on the side wall of the furnace body, and the slag outlet 3 is located in the iron reduction separation zone 6 and is located on the other end wall of the furnace body.

[0033] To enhance reduction capabilities, plasma guns 13 are installed on both sides of the furnace corresponding to lead reduction separation zone 4, zinc reduction separation zone 5, and iron reduction separation zone 6. The plasma guns 13 are positioned below the slag inlet and flush with the molten slag surface. The heads of the plasma guns 13 are inserted at an angle below the molten slag surface to a depth of 50mm–200mm. N2 gas, carbon powder, or CO gas carrying reducing agent powder is introduced into the plasma guns 13. The high-temperature, high-energy plasma generated by the plasma guns enhances reduction capabilities and reduces the energy required in traditional smelting processes.

[0034] The slag from upstream flows into the furnace through the slag inlet. In the lead reduction separation zone 4, the lead oxides in the slag react with the lead particles due to the reduction effect of the coke particles and the high temperature and high energy plasma generated by the electrodes and plasma gun. The lead is reduced. Since the boiling point of lead is relatively high, it is deposited at the bottom of the furnace in the form of molten lead. That is, the molten lead is at the bottom of the molten slag. As the molten lead falls, it continuously captures gold and silver precious metals in the molten slag and is finally released through the lead slurry outlet 9.

[0035] The lead in the slag is almost completely reduced and exists in the form of lead liquid before flowing to the zinc reduction separation zone 5. The lead-free slag reduces zinc in the zinc reduction separation zone 5. However, since the boiling point of zinc is only 907℃, the reduced zinc is discharged from the zinc flue gas outlet 10 of the zinc reduction separation zone in the form of zinc-containing flue gas.

[0036] Iron in the slag is reduced at iron reduction separation zone 6. Because iron has a high boiling point, it is also deposited as molten iron at the bottom of the slag and finally discharged from molten iron outlet 11. To prevent lead containing precious metals from mixing with the molten iron, the bottom of the furnace body has a structure that is high in the middle and low at both ends. That is, the bottom of the zinc reduction separation zone is the highest and gradually decreases towards both ends, so that the formed molten lead flows towards the front end, and the molten iron flows towards the back end after deposition. The reduced slag is discharged from the slag outlet.

[0037] Example 2:

[0038] An integrated electric furnace for reducing and separating lead, zinc, iron, and polymetallic substances in molten slag is provided, but without a plasma gun; otherwise, it is the same as in Example 1.

[0039] In this specification, the terms "an embodiment," "example," "specific example," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0040] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. An integrated electric furnace for reducing and separating lead, zinc, and iron polymetallic slag, comprising a furnace body (1), wherein the furnace body (1) is provided with a slag inlet (2) and a slag outlet (3), characterized in that: The inner cavity of the furnace body (1) is divided into a lead reduction separation zone (4), a zinc reduction separation zone (5) and an iron reduction separation zone (6) along the slag flow direction. The top of the furnace body (1) corresponding to the lead reduction separation zone (4), the zinc reduction separation zone (5) and the iron reduction separation zone (6) is provided with an electrode hole (7) and a feeding port. The furnace body (1) is provided with a lead liquid siphon outlet (9) in the lead reduction separation zone (4), a zinc flue gas outlet (10) in the furnace body (1), and an iron liquid outlet (11) in the iron reduction separation zone (6).

2. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 1, characterized in that: An electrode (12) is installed at the electrode hole (7). The head of the electrode (12) is inserted below the surface of the molten slag. The insertion depth of the head of the electrode (12) is 200 mm to 500 mm.

3. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 2, characterized in that: The electrode (12) is mounted in a liftable manner at the electrode hole (7).

4. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to any one of claims 1-3, characterized in that: The temperature of the lead reduction separation zone (4) is 1000℃~1200℃; the temperature of the zinc reduction separation zone (5) is 1200℃~1350℃; and the temperature of the iron reduction separation zone (6) is 1350℃~1550℃.

5. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 4, characterized in that: The bottom surface of the furnace body (1) corresponding to the zinc reduction separation zone (5) is the highest.

6. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 5, characterized in that: The feeding ports include coke particle feeding ports and additive feeding ports for adding lime or silica.

7. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 4, characterized in that: The lead liquid siphon outlet (9) and the slag inlet (2) are located in the lead reduction separation zone (4), and the slag inlet (2) is located above the lead liquid siphon outlet (9); the slag outlet (3) is located in the iron reduction separation zone (6).

8. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 4, characterized in that: Plasma guns (13) are installed on both sides of the furnace body corresponding to the lead reduction separation zone (4), zinc reduction separation zone (5) and iron reduction separation zone (6), with the head of the plasma gun (13) inserted at an angle below the molten slag surface.

9. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 8, characterized in that: The head of the plasma gun (13) is inserted below the surface of the molten slag, and the insertion depth of the head of the plasma gun (13) is 50mm to 200mm.

10. The electric furnace for integrated reduction and separation of lead, zinc, and iron polymetallic slag according to claim 9, characterized in that: N2, carbon powder, or CO gas carrying reducing agent powder is introduced into the plasma gun (13).

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