CN116065031A

CN116065031A - Lead matte efficient converting method and converting device

Info

Publication number: CN116065031A
Application number: CN202310045953.9A
Authority: CN
Inventors: 郭徽; 张岭; 柏韬; 张乐如
Original assignee: CINF Engineering Corp Ltd
Current assignee: CINF Engineering Corp Ltd
Priority date: 2023-01-30
Filing date: 2023-01-30
Publication date: 2023-05-05

Abstract

The invention discloses a lead matte high-efficiency converting method and a converting device, wherein the lead matte converting device comprises a hollow hearth, a charging hole is formed in the hearth, a copper hole and a slag hole are formed in the lower portion of the hearth from bottom to top, a lifting device is arranged above the hearth, a main shaft of the lifting device in the vertical direction is fixedly connected with a top-blowing spray gun, and a side-blowing spray gun is arranged on the upper portion of the hearth. The converting method can realize the deep separation of copper and lead, and the converting product is blister copper with extremely low lead content and is rich in noble metals such as Ag and the like, thereby improving the value of lead matte. The blowing method of the invention has the advantages that most Pb element volatilizes to smoke dust, the Pb element can be returned to a lead smelting system for further extraction and recovery, the blowing slag can be sent to a cement plant to be used as a raw material after copper is extracted by slag selection, and sulfur-containing flue gas can be sent to acid production after purification, so that the whole process flow has no pollution to the environment.

Description

Lead matte efficient converting method and converting device

Technical Field

The invention relates to the field of pyrometallurgy copper smelting, in particular to a lead matte efficient converting method and a converting device.

Background

Lead matte is an intermediate product with higher copper and lead content generated by preliminary fire refining of crude lead, and mainly contains Cu ₂ S、PbS、Metal sulfides such As FeS and a certain amount of elements such As, sb, ag and the like. The lead matte composition varies greatly depending on the process of the preliminary fire refining. One is a decoppering process of a lead melting pot to obtain copper dross with copper content of 10-15%, and soda ash, scrap iron, pyrite and coke are generally added in the copper dross treatment process to obtain lead matte, crude lead and slag. The lead matte generally contains the following components by mass percent of 25-55% of Cu, 10-20% of Fe, 10-35% of Pb and 8-13% of S. The other is that the crude lead adopts a continuous refining furnace copper removal process, the process can directly obtain lead matte containing 45% -55% of copper, the lead content is about 20%, the iron content and the sulfur content are very low, and most of copper and lead exist in the form of alloy. At present, the treatment process of valuable metals in lead matte is generally divided into a wet method and a fire method, and the wet smelting process mainly comprises an acid leaching method, a chlorination leaching method, an ammonia leaching method and the like, and because a large amount of lead slag is generated during leaching in the wet treatment, the solid-liquid separation and the subsequent waste slag disposal are difficult, and therefore the application is less.

At present, lead smelting enterprises mainly adopt a pyrogenic process to treat lead matte, wherein the lead matte is roughly divided into two types of traditional pyrogenic blowing and converter molten pool blowing. The traditional fire treatment process comprises a reverberatory furnace method, a blast furnace method and the like, and the methods have some problems: firstly, the efficiency is low, and 3-7 days are generally required for converting one furnace of lead matte; secondly, the energy consumption is high, and especially the thermal efficiency of the reverberatory furnace is only about 30%; thirdly, the mechanization and automation level is low; fourthly, copper and lead cannot be thoroughly separated, and crude copper can be obtained only through 2-3 working procedures. In recent years, enterprises adopt methods such as converter oxygen-enriched bottom blowing and the like to add lead matte into a furnace, add a certain amount of siliceous flux and granular coal, simultaneously blow air into a molten pool to oxidize impurities and float upwards for slagging, and the high-grade matte is deposited on the lower layer and still needs further treatment to obtain blister copper, so that no report of directly producing blister copper is provided.

Because the lead matte has complex chemical components, a comparatively ideal treatment process is not developed at present, and the requirements of low carbon, environmental protection and high efficiency of the current solid waste treatment cannot be met, so the difficult problem of comprehensive recovery of lead smelting resources is solved.

The Chinese patent with publication number of CN113817924A discloses a method for producing blister copper by smelting copper dross, which has high smelting strength, can efficiently treat copper dross and produce blister lead and blister copper products in one step, and reduces the treatment difficulty of the subsequent process. The raw materials treated by the method are copper dross, copper and lead are smelted in different areas respectively, and firstly, the smelting area and the upper smoke of the converting area can be separated, so that the two spaces can conveniently control the partial pressure of the gases respectively, and the functions of different stages are realized; secondly, the mixing of smelting slag and copper converting slag can be prevented, and the efficient recycling of copper-containing waste slag is realized; thirdly, the flow of matte to the converting area can be realized; therefore, the method of zoning smelting has better separation effect of each component and high metal recovery rate. In the method, after smelting, the temperature of the lead liquid layer is 700-800 ℃, so that the copper content in the crude lead can be reduced, and the recovery rate of copper can be increased. The above-mentioned published patents have the following drawbacks:

(1) The raw materials treated by the disclosed patent are copper dross, the copper dross is smelted at the left side of the device and then enters a right side converting area, and molten matte enters the converting area, so that the converting and slagging can be carried out by adopting single top blowing;

(2) The double-zone furnace structure adopted by the disclosed patent has higher operation difficulty in the furnace opening stage, and the problems of insufficient heat of a hearth, coke accumulation and the like easily occur when the side-blown smelting furnace is opened, so that the temperature raising effect of the side-blown smelting furnace on the area below the tuyere is limited by solely depending on the side-blown spray gun.

(3) In the smelting process of the double-zone furnace adopted by the published patent, when raw materials or furnace conditions fluctuate, such as the temperature of a molten pool is low, a retaining wall area channel is easy to be blocked, a retaining wall structure is easy to erode due to long-time hot flushing, the maintenance is difficult in a hot state, and the furnace needs to be shut down.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the high-efficiency blowing method and the blowing device for the lead matte, which realize rapid slag formation, deep impurity removal of the lead matte, prepare high-grade blister copper and solve the technical problems of incomplete copper-lead separation and low smelting efficiency in the lead matte treatment process.

In order to solve the technical problems, the invention adopts the following technical scheme: the utility model provides a plumbous matte converting device, includes hollow hearth, the charge door has been seted up on the hearth, copper mouth and slag notch have been seted up from lower supreme to the hearth lower part, elevating gear is installed to the hearth top, elevating gear is located the ascending main shaft fixedly connected with top-blown spray gun of vertical direction, the side-blown spray gun is installed on the upper portion of hearth, the side-blown spray gun includes the water-cooling wind gap, the cladding of water-cooling wind gap outside has refractory material.

The side blowing spray gun has no precedent of direct converting lead matte in industry at present, and the main reason is that a side blowing air port is protected by a water jacket, and the matte is high in sulfur content, for example, a matte melt is in direct contact with the copper water jacket and is easy to explode, so that the application coats refractory materials on the outer side of the water jacket, and the situation that the matte liquid level is high and overflows to a furnace table and is in direct contact with the copper water jacket can be prevented, and explosion is avoided. The top-blowing spray gun is cooled by gas, has no water jacket structure and has no explosion risk. The invention adopts the top-blowing spray gun to realize deep impurity removal of the matte, and prepares high-grade blister copper.

The lifting device can realize free switching of the blowing position among the gas area, the slag layer and the matte layer.

In a preferred embodiment of the invention, the height of the side-blown lance from the hearth is 1000-1200mm. The side blowing spray gun mainly sprays a slag and matte mixing area to realize the slag making process.

In a preferred embodiment of the invention, a plurality of side-blowing lances are arranged, and the side-blowing lances are arranged in a high-low two-layer arrangement. The two layers of side-blowing spray guns can greatly improve stirring kinetic energy and realize rapid slag-making reaction.

In a preferred embodiment of the invention, the side-blowing lance is a concentric sleeve lance. The side blowing spray gun can independently spray oxygen-enriched air, and can also mix and spray coal gas/pulverized coal and oxygen-enriched air to supplement heat for the melt.

In a preferred embodiment of the present invention, the top-blowing lance is a concentric sleeve lance. The top blowing spray gun can independently spray oxygen-enriched air, and can also mix and spray coal gas/pulverized coal and oxygen-enriched air to supplement heat for the melt.

In a preferred embodiment of the invention, the top-blowing lance is lowered to a minimum position 400-500mm from the hearth. The top-blowing spray gun mainly sprays a matte layer to realize a copper making process, and prevents air flow from scouring furnace bottom refractory materials.

In a preferred embodiment of the invention, a lead port is arranged below the copper port, and the lead port, the copper port and the slag port are staggered in the vertical direction.

The invention also discloses a lead matte converting method, which comprises the following steps:

s1, mixing lead matte and a slag-forming flux according to the proportion of 100:4-6, adding the mixture into the lead matte converting device of claim 1, and carrying out primary converting by using a side-blowing spray gun, wherein a matte layer and a slag layer are formed in a hearth from bottom to top after primary converting;

s2, the top-blowing spray gun is used for descending to the matte layer, secondary blowing is carried out simultaneously with the side-blowing spray gun, and a blister copper layer and a slag layer are formed in the hearth from bottom to top.

And after the lead matte and the slag-forming flux such As silica are mixed by one-time blowing, adding the mixture into the blowing device through a top feed port, starting a side blowing spray gun to perform oxidation blowing, wherein impurities such As Pb, as, sb and the like in the molten granular raw materials partially volatilize into smoke dust, part of the impurities are oxidized together with Fe element to form slag and float, valuable metals such As Cu, ag and the like are enriched in the matte phase and are deposited on the lower layer, and the process realizes Cu enrichment and part of impurities removal.

And in the secondary converting, the top-blowing spray gun is downwards detected to the matte layer, and oxygen-enriched air is blown in to carry out the second-stage converting. The impurity elements in the copper matte are fully oxidized into smoke dust or converting slag, the S element is oxidized into smoke gas, the smoke gas is cooled and purified and then sent to an acid making system, liquid blister copper rich in noble metals is generated and is deposited below a copper matte layer, and a copper opening at the lower part is opened to discharge copper liquid when the liquid level reaches a preset height.

The raw material lead matte contains 25-55% of Cu, 10-35% of Pb, 8-12% of Fe and 800-2000g/t of Ag.

In a preferred embodiment of the invention, the oxygen-enriched and pulverized coal is blown through the side-blown lance during the one-time converting in the step S1, and the pulverized coal rate is 7-10%. The heat required by blowing is partially provided by oxidation heat release of metal sulfide in the raw materials, and the rest is provided by burning pulverized coal blown by a side blowing spray gun.

In a preferred embodiment of the invention, the primary converting temperature is 1000-1200 ℃, and the primary converting time is 6-10 hours, so that the complete melting of the matte and slag is ensured.

In a preferred embodiment of the present invention, the secondary converting temperature in S2 is 1100-1300 ℃, and the secondary converting time is 10-14 hours.

The raw materials processed by the method are lead matte, the copper content of the lead matte is different from that of the copper matte in the second step in Chinese patent with the publication number of CN113817924A by half, the lead matte is only about 30%, the Fe, pb, as, sb and other impurities are very high in content, a large amount of slag is required, the slag forming period cannot be self-heated according to the heat balance calculation result, and the fuel is required to be supplemented, so that slag forming is slow due to independent top blowing, a large amount of fuel is consumed by long-time heat preservation of a melt, and the furnace processing capacity is low. According to the invention, 10 side-blowing spray guns are arranged along the circumferential direction of the device, so that the stirring kinetic energy can be greatly improved, the rapid slag-making reaction is realized, and meanwhile, the top-blowing gun head is downwards detected below the horizontal line of the side-blowing air port by utilizing the advantage of adjustable height of the top-blowing gun, the deep impurity removal of copper matte is realized, and the high-grade blister copper is prepared.

At present, lead matte treatment is most widely applied in a reverberatory furnace process, and compared with the traditional reverberatory furnace process, the process provided by the invention has the following obvious advantages: the side top-blown molten pool smelting replaces the nearly stationary molten pool smelting of a reverberatory furnace, the stirring intensity of the melt is increased, the dynamic conditions of chemical reaction are improved, the reaction time is shortened, and the oxygen-enriched air is well mixed in the melt, so that impurities are removed more thoroughly, the heat utilization rate is improved, and the burnup is obviously reduced; meanwhile, the traditional reverberatory furnace is used for blowing the lead matte into 80% black copper, at least two furnaces are needed, and the intermediate furnace burden needs to be transferred once.

Compared with the current converter molten pool smelting process for treating lead matte, the process provided by the invention has the advantages that the burner in the converter is omitted, most of heat required by furnace charge melting and reaction is derived from impurity element oxidation heat release, the heat loss is less due to the submerged combustion supplementation of carbonaceous fuel in the melt, the side-blown smelting stirring kinetic energy is larger, and the blowing time of the process can be shortened to one third compared with the current converter process under the condition that crude copper is blown out.

In order to further improve the recycling efficiency of resources and combine the ideas of lead matte molten pool blowing and matte top blowing, the invention provides a smelting method capable of efficiently processing lead matte materials and develops a matched smelting device, namely a composite blowing furnace, and the whole processes of raw material melting, slag making and copper making can be completed in the same molten pool space through the cooperation of a side blowing spray gun and a top blowing spray gun, and experiments show that: the method has the advantages that copper and lead are thoroughly separated, and the lead content of the produced crude copper is less than 0.3 percent, so that the crude copper can be directly fed into a copper anode furnace for refining. The converting efficiency is 10 times higher than that of the traditional method. The method has the advantages of low energy consumption, high automation degree, no environmental pollution and great significance for improving the technical equipment level of lead smelting enterprises.

This patent sets up side-blown spray gun and liftable top-blown spray gun simultaneously, and when the problem such as easily appearing hearth heat is not enough, coke is piled up when the side-blown smelting furnace is opened the stove, can utilize top-blown spray gun to blow into oxygen boosting air combustion-supporting or directly blow into fuel + oxygen boosting air combustion heat compensation under the circumstances that the side-blown spray gun did not stop work, nimble regulation hearth temperature effectively prevents that the hearth from freezing. The method has strong adaptability to the treatment of lead matte materials with larger fluctuation of sulfur content.

The invention improves the side top blowing function into the same reaction space, simplifies the structure in the furnace, can effectively prolong the service life of the furnace body and increases the operation rate.

Compared with the prior art, the invention has the following beneficial effects: 1) The blowing device combines the advantages of side blowing and top blowing of a molten pool, and the lead matte is blown in a segmented mode in the same reaction space, so that the blowing strength is improved, the whole process flow is greatly shortened, the blister copper is produced in one step, and the blowing method is low in energy consumption and easy to operate. 2) The converting method can realize the deep separation of copper and lead, and the converting product is blister copper with extremely low lead content and is rich in noble metals such as Ag and the like, thereby improving the value of lead matte. 3) The blowing method of the invention has the advantages that most Pb element volatilizes to smoke dust, the Pb element can be returned to a lead smelting system for further extraction and recovery, the blowing slag can be sent to a cement plant to be used as a raw material after copper is extracted by slag selection, and sulfur-containing flue gas can be sent to acid production after purification, so that the whole process flow has no pollution to the environment.

Drawings

Fig. 1 is a schematic structural diagram of a lead matte converting device according to an embodiment of the invention.

Fig. 2 is a flow chart of a process of oxygen-enriched side blowing-oxygen-enriched top blowing of lead matte in an embodiment of the invention.

Fig. 3 is a schematic structural view of a side-blowing lance according to an embodiment of the invention.

Wherein: 1-furnace shell, 2-furnace hearth, 3-lead port, 4-copper port, 5-slag port, 6-side blowing spray gun, 7-top blowing spray gun, 8-charging port, 9-steel frame, 10-flue, 11-waste heat recovery device, 12-flue gas outlet, 13-tuyere water jacket, 14-refractory material and 15-furnace shell water jacket.

Detailed Description

Example 1

The device for one-step copper smelting by lead matte oxygen-enriched side blowing-oxygen-enriched top blowing according to the invention is described below with reference to the accompanying drawings.

As shown in figure 1, the furnace body for processing lead matte by oxygen-enriched side blowing-oxygen-enriched top blowing disclosed by the invention has a cylindrical structure, and only one continuous reaction space is formed from top to bottom in the furnace. Wherein the furnace shell 1 is formed by enclosing a steel plate with the thickness of 20-30mm, and rib plates are arranged on the periphery of the steel plate for reinforcing. The hearth 2 is built by a plurality of layers of refractory bricks, the bottom is buried with a temperature thermocouple, and the furnace wall is buried with a water cooling element. The furnace bottom is provided with a lead port 3, and lead can be discharged periodically when lead in the furnace burden is high and crude lead is generated. The upper part of the lead port is provided with a copper port 4, the upper part of the copper port is provided with a slag port 5, and for facilitating the opening operation, each straight-line port is arranged at a certain angle in the circumferential direction of the hearth and is respectively provided with an independent chute. A plurality of side blowing spray guns 6 are distributed at the middle upper part of the hearth along the circumferential direction, the spray guns are distributed in two layers of height, the spray guns are immersed in a slag layer during blowing, the spray gun body is of a multi-layer concentric sleeve structure, oxygen-enriched air can be independently blown, coal gas/pulverized coal and oxygen-enriched air can be mixed to be blown to supplement heat for a melt, and the diameter of the outer layer of the oxygen-enriched air is between phi 30 and phi 50. The side-blown spray gun manufacturer is the Western-style Hibiscus machine electric company.

As shown in fig. 3, the outside of the water cooling tuyere 13 of the side blowing spray gun 6 is coated with a refractory material 14, and the refractory material is aluminum chrome brick.

A top-blowing spray gun 7 is inserted into the center of the furnace roof, the tail part of the spray gun is fixed on the sliding lifting device, the vertical movement is realized through a hoisting mechanism, and the position of the gun head can be freely switched among a gas area, a slag layer and a matte layer. The top blowing spray gun body is of a multilayer concentric sleeve structure, and can be independently blown with oxygen-enriched air or simultaneously blown with coal gas/pulverized coal and oxygen-enriched air, so that the functions of converting, supplementing heat and adjusting the atmosphere of a hearth are realized, and the diameter of the outer layer of the gun body is between phi 50 and phi 76. The charging hole 8 and the water cooling flue 9 are positioned at the upper part of the furnace body, the flue is of a circular structure, a water channel surrounded by channel steel is arranged at the outer side of the steel plate, and an anchoring piece is arranged at the inner side of the steel plate and used for anchoring refractory materials. The top of the water-cooling flue 10 is provided with an ash removing opening, and the inlet and the outlet are provided with a thermocouple temperature measuring device and a pressure measuring device. The waste heat recovery device 11 is of a rectangular structure, the width of the waste heat recovery device is 4m-5m, and an ash removal device is arranged. The flue outlet 12 consists of a water cooled wall or water cooled jacket at an angle of 30 ° -45 ° to vertical.

The oxygen-enriched side blowing-oxygen-enriched top blowing one-step copper smelting device is operated in a reaction space in a sectioning way, the upper part of a hearth is a dead zone, the lower molten pool in the blowing process is divided into two layers or three layers, a slag layer, a copper matte layer and a lead liquid layer are sequentially arranged from top to bottom, and the raw materials can be generated when the content of elemental lead is higher and are required to be discharged periodically. A plurality of side blowing spray guns 6 are uniformly arranged on the furnace wall around the slag layer and immersed in slag, oxygen-enriched air can be blown into the furnace to regulate oxidizing atmosphere and disturb melt, or fuel is blown into the furnace to provide a heat source, and granular raw materials added from a charging port at the top of the furnace are stirred by blown high-speed air flow in the slag layer and gradually heated to melt. Because the tuyere is arranged at the upper part of the whole molten pool, only slag is strongly stirred, the copper matte layer at the lower part is relatively in a static state, the settled copper matte in the hearth can not be heated by the fuel blown by the spray gun, and the heat is mainly conducted from the molten pool. The direct slag discharge port is arranged at the height above the slag layer tuyere to regularly discharge the converting slag, so that the problem that the subsequent treatment is difficult due to the fact that a large amount of Cu element in the converting section is oxidized and dissolved into the slag can be avoided. If the crude lead content in the furnace burden is higher, part of the crude lead content is settled to the bottom of the hearth, the lead liquid can be discharged through a lead port arranged at the bottom of the furnace wall, so that the influence of a converting section on the crude copper quality is avoided.

The blowing slag is discharged and enters a blowing section, the liftable top-blowing spray gun 7 is vertically downwards detected to the copper matte layer to be blown with oxygen for blowing, and the required heat is from oxidation heat release of metal sulfide. In the blowing process, the lower molten pool is divided into three layers, namely a copper slag layer, a copper matte layer and a copper liquid layer from top to bottom. The position of the spray gun is timely adjusted along with the thickness change of the matte layer during blowing. The molten pool below the muzzle is relatively static, and the copper liquid generated by the interaction reaction can be precipitated at the lower part to form a metal molten pool, and is discharged from the copper port at the lower part of the furnace wall. And after partial oxidation slagging, the impurity elements float upwards to enter a copper slag layer, and partial volatilization is carried out to smoke dust.

The flue gas of the side blowing converting section and the flue gas of the top blowing converting section can be sent into the waste heat recovery device 11 through the water cooling flue 10, then enter the dust removal system to recover smoke dust, and then can be purified and sent to the acid making system.

The process of the oxygen-enriched side blowing-oxygen-enriched top blowing treatment of lead matte according to the present invention is described below with reference to the accompanying drawings.

As shown in fig. 2, the process for treating lead matte by oxygen-enriched side blowing-oxygen-enriched top blowing comprises the following steps: the raw material lead matte contains 33wt% of Cu, 12wt% of Pb and 9wt% of Fe. The lead matte and the silica are mixed according to the proportion of 100:5 (Pb, fe and other impurities in the lead matte are higher than those in the copper matte in the published patent, and Pb and Fe oxides are alkaline oxides, so that acid oxides are added in the process to form slag, the consumption of the silica is higher than that in the published patent, the effect is that the slag with low melting point is produced), the slag is sent to a charging port through a belt and added into a converting furnace, a side-blowing spray gun arranged on a slag layer is blown in to be rich in oxygen, and the converting temperature is 1200 ℃ after the slag is converted for 8 hours. The lead matte completes the melting and liquid phase layering process in the hearth, 10wt% of powdered coal is added to supplement heat, and the fuel can be added into granular coal through a charging hole or sprayed into the powdered coal through a side blowing spray gun. The purpose of adding silica in the converting section is to form a eutectic substance with the floating impurity element oxide, improve the fluidity of slag, and form a copper matte phase with 65-75% copper grade with FeS after CuS oxidation. The blowing process needs to pay attention to the liquid level, the interface between slag and matte is kept not higher than the position of a slag hole, blown slag is discharged through the slag hole, copper is extracted by floatation, and flue gas is cooled and dedusted and then sent to an acid making system.

When the second-stage converting section starts, adding 0.6wt% of silica (relative to copper matte) into a molten pool through a furnace top charging port, blowing oxygen-enriched air into a top-blowing spray gun arranged at the upper part of a furnace body for converting, wherein the spray gun can control oxygen partial pressure to realize two-step converting of slag making and copper making, the converting time is 12h, and the converting temperature is 1300 ℃. After being oxidized, fe and other impurity elements float upwards to form slag with added acid flux, and part of Cu element is oxidized into slag at the same time, and the slag type copper slag with eutectic point in the converting zone mainly comprises: feO-SiO ₂ FeO-SiO ₂ -Cu ₂ O type, feO-SiO ₂ -Cu ₂ O-PbO type. Copper matte is oxidized to produce blister copper which is deposited at the bottom of the hearth, and copper liquid is discharged from a copper port at the lower part of the furnace wall. The blowing section has small copper slag amount and higher copper content, and can not release lead matte which is melted in the next batch to carry out interaction reaction, so as to recycle Cu element in the lead matte. The process can realize the effective separation of copper and lead in the lead matte and produce blister copper in one step.

The converting and converting flue gas is cooled by a water cooling flue and waste heat recovery device and then sent to a dust collection device, and is converged into an acid making system through a purification process.

In S1, the lead matte oxidation converting process is completed by an immersed multi-layer side-blowing spray gun 6 arranged on the side wall of the furnace wall, part of heat required by converting is provided by oxidation heat release of metal sulfide in the raw material, the rest is provided by blowing pulverized coal into the spray gun for combustion, and the pulverized coal rate is 7-10%. The lead matte and flux silica in the oxidation blowing stage form white matte with copper grade of 65-75% and eutectic blowing slag under the blowing action of oxygen-enriched air and fuel, and the slag mainly comprises: feO-SiO ₂ PbO type, feO-SiO ₂ -PbO-SbO ₂ FeO-SiO ₂ -PbO-ZnO type. After the oxidation converting stage is finished, converting slag is discharged from the slag hole 5, the interface between slag and matte is controlled not to exceed the height of the slag hole in the converting process, and after part of smoke dust is captured by the waste heat recovery device 11, the smoke dust is discharged from the smoke outlet 12Sending the flue gas into a dust collection system for recycling, purifying the flue gas, and sending the flue gas into an acid making system.

And after the converting section is finished, a slag port is opened to discharge converting slag with lower copper content, and a top-blown oxygen lance is extended downwards until the matte layer is blown with oxygen-enriched air for second-stage converting. The impurity elements in the copper matte are fully oxidized into smoke dust or converting slag, the S element is oxidized into smoke gas, the smoke gas is cooled and purified and then sent to an acid making system, liquid blister copper rich in noble metals is generated and is deposited below a copper matte layer, and a copper opening at the lower part is opened to discharge copper liquid when the liquid level reaches a preset height.

And S2, the copper matte converting process is completed by downwards extending the liftable top-blowing oxygen lance 7 to the copper matte layer, the lance can control the oxygen partial pressure to realize two-step converting of slag making and copper making, the height of the top-blowing lance is adjusted in real time along with the reaction in the converting process, and the converting temperature is 1100-1300 ℃. And the crude copper obtained by converting and converting slag are settled and separated in the hearth 2, copper liquid is discharged from the copper port 4, the converting slag is not discharged, and Cu element in the crude copper can be recovered by reacting with the furnace burden melted in the next batch. The converting section eutectic copper slag mainly comprises: feO-SiO ₂ FeO-SiO ₂ -Cu ₂ O-type and FeO-SiO ₂ -Cu ₂ O-PbO type. The flue gas in the converting area can be sent to the dust collecting device after passing through the water-cooling flue, and the purified flue gas is collected into the acid making system.

In the method of the embodiment, the copper matte produced by the converting section contains 70% of Cu and less than 3% of Pb. Compared with the matte produced by traditional reverberatory furnace fire smelting, the Pb content is reduced by 5%, and the copper grade is improved by about 20%. In the embodiment, the copper content (mass fraction, the same applies hereinafter) of the blister copper is more than or equal to 95%, the Pb content is less than or equal to 0.3%, the Ag content is more than or equal to 4500g/t, the Pb impurity removal rate is more than or equal to 99.5%, and the Ag recovery rate is more than or equal to 99%, compared with the traditional reverberatory furnace fire converting process, the blister copper grade is improved by 15%, and the lead matte converting and copper-making converting process is completed by one device, so that the converting period of several days to tens of days in the original furnace is shortened to be within 24 hours, and the converting efficiency is greatly improved.

The Chinese patent with publication number of CN113817924A adopts a double-zone furnace smelting process, the double-zone furnace smelting process has the obvious advantages that different redox atmospheres can be controlled in two smelting areas, but the defects of high furnace opening difficulty, short service life of a retaining wall, easy blockage of a channel and shutdown of maintenance are obvious, the copper dross is a raw material in the disclosed patent, a large amount of lead oxide is required to be reduced, a double-zone structure is considered, but for lead matte, the slagging and copper-making processes are strong oxidizing atmospheres, the atmospheres are not required to be divided, the inherent defects of the double-zone furnace are avoided by adopting a single-zone structure, the operation rate is effectively improved, the problem of liquid pressure balance on two sides of the retaining wall in the double-zone furnace operation process is also avoided by adopting the single-zone structure, the operation difficulty of the blowing process is reduced, and the stability of product quality is ensured.

The Chinese patent with publication number of CN113817924A and the Chinese patent are both intended to exert the advantages of high stirring kinetic energy, high processing capacity and low energy consumption of the oxygen-enriched side-blown molten pool smelting technology, the direct superposition of the top-blown function in the side-blown smelting area not only avoids the defects of a double-zone furnace, but also improves the flexibility of the furnace type operation, the side-blown submerged combustion can supplement the heat of an upper melt when the heat of the furnace fluctuates in the blowing stage and the blowing process, and the top-blown spray gun is different from the prior art, adopts a multi-layer sleeve spray gun, can simultaneously blow oxygen-enriched air and fuel into the melt, supplements the heat of a lower melt, overcomes the defect of slow downward transfer of the heat of the side-blown furnace, effectively reduces the risk of dead furnaces, and improves the adaptability of the process to lead-matte raw materials with different sulfur contents.

Claims

1. The utility model provides a plumbous matte converting device, includes hollow hearth (2), feed inlet (8) have been seted up on hearth (2), copper mouth (4) and slag notch (5) have been seted up from lower supreme in hearth (2) lower part, elevating gear is installed to hearth (2) top, elevating gear is located vertical ascending main shaft fixedly connected with top-blown spray gun (7), a serial communication port, side-blown spray gun (6) are installed on the upper portion of hearth (2), side-blown spray gun (6) include wind gap water jacket (13), the cladding of wind gap water jacket (13) outside has refractory material (14).

2. The lead matte converting device according to claim 1, characterized in that the height of the side-blowing lance (6) from the furnace bottom is 1000-1200mm.

3. The lead matte converting device according to claim 1 or 2, wherein a plurality of side-blowing lances (6) are installed, and the side-blowing lances (6) are arranged in two layers, a higher layer and a lower layer.

4. The lead matte converting device according to claim 1 or 2, characterized in that the side-blowing lance (6) is a concentric sleeve lance.

5. The lead matte converting device according to claim 1 or 2, characterized in that the top-blowing lance (7) is a concentric sleeve lance.

6. The lead matte converting device according to claim 1 or 2, characterized in that the lowest position of the top-blowing lance (7) is 400-500mm from the furnace bottom.

7. The blowing method of the lead matte is characterized by comprising the following steps of:

s1, mixing lead matte and silica according to the proportion of 100:4-6, adding the mixture into the lead matte converting device of claim 1, and carrying out primary converting by using a side-blowing spray gun, wherein a matte layer and a slag layer are formed in a hearth from bottom to top after primary converting;

8. The method according to claim 7, wherein oxygen-enriched and pulverized coal is blown through a side-blowing lance during the primary blowing in S1, and the pulverized coal ratio is 7-10%.

9. The lead matte converting method according to claim 7, wherein the primary converting temperature is 1000-1200 ℃, and the primary converting time is 6-10 hours.

10. The lead matte converting method according to claim 7, wherein the secondary converting temperature in S2 is 1100-1300 ℃, and the secondary converting time is 10-14 hours.