阅读说明：本技术 一种粗铅连续精炼脱铜并产出高品位冰铜的方法 (Method for continuous refining and decoppering of lead bullion and producing high-grade matte ) 是由 曹军超 张军力 黄晓丰 冯长征 于 2021-01-27 设计创作，主要内容包括：本发明属于有色金属冶炼技术领域,公开了一种粗铅连续精炼脱铜并产出高品位冰铜的方法,包括以下步骤：将一部分新型脱铜剂随高温液态粗铅通过连续脱铜炉进铅口加入到连续脱铜炉原料室,与降温析出的高熔点物质反应生成硫化物；将剩余新型脱铜剂随低温液态粗铅通过返回通道加入到连续脱铜炉返回室,同时进行熔析脱铜和硫化脱铜；连续脱铜炉返回室底部低温粗铅中熔析出的铜金属和硫化脱铜形成的含铜硫化物一起上浮至液体表面,与连续脱铜炉原料室上浮至液体表面的硫化物反应后,形成含铜较高的冰铜层。本发明方法只需要加入脱铜剂,即可满足降低粗铅含铜和产出高品位冰铜的目的,不需要加入额外的辅料纯碱和铁屑,辅料消耗少。(The invention belongs to the technical field of non-ferrous metal smelting, and discloses a method for continuous refining and decoppering of lead bullion and producing high-grade matte, which comprises the following steps: adding a part of the novel decoppering agent into a continuous decoppering furnace raw material chamber along with high-temperature liquid lead through a lead inlet of the continuous decoppering furnace, and reacting with a high-melting-point substance separated out by cooling to generate sulfide; adding the residual novel copper removing agent and low-temperature liquid crude lead into a return chamber of the continuous copper removing furnace through a return channel, and simultaneously carrying out liquation copper removal and vulcanization copper removal; copper metal melted out from low-temperature crude lead at the bottom of the continuous decoppering furnace returning chamber and copper-containing sulfide formed by sulfurizing decoppering float to the liquid surface together, and after the copper metal reacts with the sulfide floating to the liquid surface in the continuous decoppering furnace raw material chamber, an ice copper layer with high copper content is formed. The method can meet the aims of reducing the copper content of the crude lead and producing high-grade matte only by adding the decoppering agent, does not need to add extra auxiliary materials such as soda ash and scrap iron, and has low auxiliary material consumption.)

1. A method for continuous refining and decoppering of lead bullion and producing high-grade matte is characterized by comprising the following steps:

step A: preparing a novel copper removing agent, adding a part of the novel copper removing agent into a continuous copper removing furnace raw material chamber through a lead inlet of a continuous copper removing furnace along with high-temperature liquid crude lead with the temperature of 800-1100 ℃, reacting with a high-melting-point substance separated out by cooling to generate a sulfide, dissolving the sulfide into the crude lead firstly and then floating to the liquid surface;

and B: adding the residual novel decoppering agent into a continuous decoppering furnace return chamber through a return channel along with low-temperature liquid lead which is circularly cooled to 360-460 ℃, and simultaneously carrying out liquation decoppering and vulcanization decoppering on the low-temperature liquid lead at the bottom of the continuous decoppering furnace return chamber;

and C: copper metal melted out from low-temperature crude lead at the bottom of the continuous copper removing furnace returning chamber and copper-containing sulfide formed by copper sulfide removal float up to the liquid surface together, and after the copper metal reacts with the sulfide floating up to the liquid surface in the continuous copper removing furnace raw material chamber, an ice copper layer with high copper content is formed;

step D: the continuous decoppering furnace returns to the bottom of the chamber, produces crude lead with low copper content through liquation decoppering and copper sulfide decoppering, and flows out of the distribution pot through siphon;

step E: controlling the temperature of an upper molten pool in the continuous copper removing furnace at 1100-1250 ℃, and discharging the copper matte from the copper matte port when the thickness of the copper matte layer on the liquid surface is more than 15 cm.

2. The method for continuous refining decoppering of lead bullion and producing high-grade matte according to claim 1, wherein the novel decoppering agent is one of sodium sulfide or pyrite.

3. The method for continuous refining decoppering of lead bullion and producing high-grade matte according to claim 1, characterized in that the novel decoppering agent is a mixture of sodium sulfide and pyrite.

4. The method for continuous refining decoppering of lead bullion and producing high-grade matte according to claim 1, characterized in that the sum of the sulfur in the novel decoppering agent and the sulfur in the lead bullion is 0.25-0.35 times the amount of copper metal in the lead bullion.

5. The method for continuous refining decoppering of lead bullion and producing high-grade matte according to claim 1, wherein a part of the novel decoppering agent in the step A accounts for 10% -40% of the total amount of the novel decoppering agent; and the residual novel decoppering agent in the step B accounts for 60-90% of the total amount of the novel decoppering agent.

6. The method for continuous refining decoppering of bullion and producing high-grade matte according to claim 1, wherein the temperature of the upper molten pool in the continuous decoppering furnace is controlled to 1100-1250 ℃ in the step E, and when the thickness of the matte layer on the liquid surface is more than 15cm and less than 40cm, the matte is discharged from the matte port.

7. The method for continuous refining decoppering of bullion and producing high-grade matte according to claim 1, characterized in that the continuous decoppering furnace is a reverberatory type refining furnace.

Technical Field

The invention belongs to the technical field of non-ferrous metal smelting, and relates to a method for continuous refining and decoppering of lead bullion and producing high-grade matte.

Background

For the lead smelting industry, two methods of fire refining and electrolytic refining are generally adopted for crude lead refining, and no matter which method is adopted, the crude lead needs to be subjected to a copper removing procedure by the fire method. At present, two methods of copper removal by adding sulfur and copper removal by liquation are generally adopted for copper removal, and both the two methods can adopt two operation modes of interruption and continuity.

The discontinuous operation is generally completed in a copper removing pot, the crude lead is firstly added into the copper removing pot for remelting, then sulfur, rosin or sawdust and the like are added into the copper removing pot for stirring, and the copper is removed by cooling and liquating. The intermittent operation mainly produces crude lead with low copper content and copper scum, and the crude lead is cast into an anode plate for electrolytic refining; the copper dross is transferred to a copper dross treatment process to recover lead metal therein and copper metal therein in the form of lead matte.

Continuous operation is generally completed in a reverberatory copper removing furnace, copper is separated out by keeping a proper temperature gradient of lead liquid in a molten pool, lead copper matte is generated by adding vulcanizing agent sulfur, pyrite or high-grade lead concentrate, and lead of the lead copper matte is reduced by adding soda ash and scrap iron. The current continuous operation mainly comprises the following steps: (1) lead matte has high lead content and low copper content, and influences lead recovery rate and crude copper converting in the next procedure; (2) the consumption of the auxiliary materials such as soda ash, scrap iron and the like is large, and the cost is high; (3) a yellow slag layer is easily generated at the upper part of the molten pool to form an interlayer, so that production accidents are easily caused; accretion is easily generated at the bottom of the molten pool, which affects the service life of the furnace. (4) High temperature of the molten pool and high fuel consumption.

The patent of invention with the publication number CN 102978416B discloses a device and a method for continuously removing copper from liquid lead bullion: the decoppering agent is sawdust, lead sulfide or lead oxide, and the decoppering agent is added into the furnace from a top lead inlet. First, the use of the decoppering agents saw dust and lead oxide do not have the effect of copper sulfide decoppering, and the surface still produces a large amount of copper dross. Secondly, lead sulfide is added into the furnace from the top, and cannot contact low-temperature lead bullion at the bottom of a molten pool due to large specific gravity difference with the lead bullion, and the effect of copper removal by vulcanization cannot be achieved; the lead sulfide added at the top can only be melted out from the bottom and floats to the copper metal at the top for a sulfurization reaction to form lead copper matte which is higher in lead content.

The invention discloses a method for continuously decoppering crude lead, which is characterized in that nitrogen or inert gas is introduced into a molten pool for stirring and cooling, the crude lead at the bottom of the molten pool can achieve the purpose of cooling, liquating and removing copper, but the gas can cause the temperature of a yellow slag layer at the upper part of the crude lead to be reduced in the rising process, so that the formation of an interlayer (also called a furnace knot) is aggravated, and the normal production is not facilitated. The vulcanizing agent used in the process is lead concentrate, pyrite or sulfur dross containing 20-30% of sulfur, the vulcanizing agent is added from a cold charge adding port at the top and is not added from a lead inlet at the end together with the crude lead, and the method cannot achieve the effect of copper removal by vulcanization because the vulcanizing agent cannot be in direct contact with the low-temperature crude lead at the bottom.

The patent with the publication number of CN 103924098B discloses a continuous refining furnace for lead bullion and a refining method, in the method, lead bullion is added into the furnace from a lead bullion inlet at one end of the continuous refining furnace, copper matte is discharged from a copper matte port at the other end, and a vulcanizing agent is added into a cooling chute at the side part. The melting pool is internally provided with three partition walls which divide the melting pool area into a return area, a product area and a circulating area from a feeding end in sequence. Since the return zone is close to the crude lead inlet, the return zone is also the raw material chamber of the furnace kiln in actual production, and high-temperature liquid crude lead flows into the furnace from the crude lead inlet at the upper part and contacts with low-temperature crude lead at the bottom when the return zone (also called the raw material chamber) is settled downwards. The metal copper, arsenic and antimony dissolved in the original liquid high-temperature lead bullion can form high-melting-point substances, namely yellow slag, and the yellow slag is separated out and forms furnace adhesion to a furnace wall, so that the volume of a furnace kiln molten pool is reduced, and finally the furnace has to be shut down for treatment. In addition, the vulcanizing agent used in the method is a conventional vulcanizing agent, the copper content of the produced matte is only 35% and the lead content is about 20%, so that the method not only causes low lead recovery, but also influences the converting of blister copper.

The invention patent with application publication No. CN 110184473A discloses a novel method for removing copper and tin from crude lead, wherein a vulcanizing agent used in the method is pyrite, and scrap iron and soda are still required to be added to reduce lead content in matte while the vulcanizing agent pyrite is used, so that the method inevitably increases the cost for removing copper from crude lead. In addition, a small amount of slag is generated in the furnace, manual slag skimming is needed to remove the slag, and high-melting-point substances such as yellow slag and the like are generated in the slag, so that the slag has a high melting point and is not easy to melt.

The continuous decoppering furnaces of Jiangxi copper industry lead-zinc metal Limited company and Shenyang smelting plant all adopt rectangular reverberatory furnace types, and the continuous decoppering furnaces of the two plants are different: the cooling of the crude lead of the Jiangxi copper industry lead-zinc metal Limited company is carried out in an external cooling mode, the used vulcanizing agent is sulfur, the lead copper matte contains 45-49% of copper and 30% of lead, and the blowing of the copper matte not only affects the quality of the crude copper but also affects the recovery rate of the lead; in addition, the furnace raw material chamber needs to be frequently shut down due to more accretions. The cooling of crude lead in the Shenyang smelting plant is carried out in a furnace cooling mode, the used vulcanizing agent is high-grade lead concentrate, lead in lead matte generated in the smelting process is about 30 percent, and the lead in lead matte still needs to be reduced by adopting a soda iron chip method (soda and iron chips). After the soda ash and the scrap iron are added, the lead content of the lead copper matte can be reduced, but the copper content of the lead copper matte is also reduced, and the copper content of the lead copper matte is only 30-40 percent finally. The matte has low copper content and high iron content, and has high slag rate and low copper recovery rate during converting.

Disclosure of Invention

The invention aims to provide a smelting method with high lead recovery rate, high copper content of lead matte, low lead content, low melting point, less accretion, less auxiliary material consumption and low processing cost aiming at the defects and the defects in the existing continuous decoppering process of lead bullion.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a method for continuous refining and decoppering of lead bullion and producing high-grade matte, which comprises the following steps:

step A: preparing a novel copper removing agent, adding a part of the novel copper removing agent into a continuous copper removing furnace raw material chamber through a lead inlet of a continuous copper removing furnace along with high-temperature liquid crude lead with the temperature of 800-1100 ℃, reacting with a high-melting-point substance separated out by cooling to generate a sulfide, dissolving the sulfide into the crude lead firstly and then floating to the liquid surface;

and B: adding the residual novel decoppering agent into a continuous decoppering furnace return chamber through a return channel along with low-temperature liquid lead which is circularly cooled to 360-460 ℃, and simultaneously carrying out liquation decoppering and vulcanization decoppering on the low-temperature liquid lead at the bottom of the continuous decoppering furnace return chamber;

and C: copper metal melted out from low-temperature crude lead at the bottom of the continuous copper removing furnace returning chamber and copper-containing sulfide formed by copper sulfide removal float up to the liquid surface together, and after the copper metal reacts with the sulfide floating up to the liquid surface in the continuous copper removing furnace raw material chamber, an ice copper layer with high copper content is formed;

step D: the continuous decoppering furnace returns to the bottom of the chamber, produces crude lead with low copper content through liquation decoppering and copper sulfide decoppering, and flows out of the distribution pot through siphon;

step E: controlling the temperature of an upper molten pool in the continuous copper removing furnace at 1100-1250 ℃, and discharging the copper matte from the copper matte port when the thickness of the copper matte layer on the liquid surface is more than 15 cm.

Further, the novel decoppering agent is one of sodium sulfide or pyrite.

Further, the novel decoppering agent is a mixture of sodium sulfide and pyrite.

Further, the sum of the sulfur in the novel decoppering agent and the sulfur in the crude lead is 0.25-0.35 times of the amount of copper metal in the crude lead.

Further, a part of the novel decoppering agent in the step A accounts for 10% -40% of the total amount of the novel decoppering agent; and the residual novel decoppering agent in the step B accounts for 60-90% of the total amount of the novel decoppering agent.

Further, the temperature of an upper layer molten pool in the continuous copper removing furnace is controlled at 1100-1250 ℃ in the step E, and when the thickness of the copper matte layer on the liquid surface is more than 15cm and less than 40cm, the copper matte is discharged from the copper matte port.

Further, the continuous decoppering furnace is a reverberatory type refining furnace.

Compared with the prior art, the invention has the beneficial effects that:

1. the decoppering agent is divided into two parts which are respectively contacted with high-temperature liquid crude lead and low-temperature liquid crude lead, wherein the decoppering agent added in the process of flowing into the raw material chamber in the furnace along with the high-temperature liquid crude lead can vulcanize high-melting-point substance metallic copper and yellow slag (a combination of copper arsenide and copper antimonide) separated out in the process of settling the raw material chamber of the continuous decoppering furnace into low-melting-point substances, thereby reducing the generation of furnace accretions in the raw material chamber and prolonging the service life of the furnace and the kiln. In addition, the decoppering agent is provided with sodium sulfide, and sodium matte with a lower melting point can be generated together with lead-copper sulfide, so that the generation of accretions on the upper part of a molten pool is reduced.

2. The method can achieve the aims of reducing the copper content of the crude lead and producing high-grade matte only by adding the decoppering agent, does not need to add extra auxiliary materials such as soda ash and scrap iron, and has low auxiliary material consumption.

3. The copper matte obtained by the invention has high copper content and can be directly blown: because the content of other elements such as Pb and Fe in the copper matte is low, the content of the main element Cu is high, the copper content in the copper matte is as high as 55-75%, and the copper matte can be transported to a copper plant to be directly blown into crude copper.

4. The method has the advantages of high lead recovery rate: the lead content of the matte is only 2-6%, which is far lower than that of the matte produced by the conventional crude lead continuous decoppering, so the lead recovery rate is higher.

Detailed Description

The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art. The test methods in the following examples are conventional methods unless otherwise specified.

The liquid lead bullion raw materials adopted in the following embodiments are from a front-end lead smelting process, and the temperatures of the liquid lead bullions from different lead smelting furnaces are all higher than 800 ℃; the continuous decoppering furnace is a reverberatory refining furnace.

Example one

The lead bullion in this example had the following composition: pb: 97%, Cu: 1%, S: 0.2%, As: 0.4%, Sb: 1.0 percent of the total weight of the liquid lead bullion, and the balance of impurities, wherein the total weight of the liquid lead bullion is 100 t. Sodium sulfide (analytically pure, 99%) is used as a novel decoppering agent, and the total amount of the sodium sulfide is 0.3 t.

(1) 0.06t of sodium sulfide is added into a continuous decoppering furnace raw material chamber along with high-temperature liquid crude lead with the temperature of more than 800 ℃ through a lead inlet of the continuous decoppering furnace, and reacts with high-melting-point substances such as metallic copper, yellow slag and the like precipitated by cooling to generate sulfide with relatively low melting point and specific gravity so as to reduce the generation of furnace accretion, and the sulfide is dissolved into the crude lead firstly and then floats to the liquid surface.

(2) And adding the residual 0.24t of sodium sulfide into the continuous decoppering furnace return chamber through a return channel, wherein the temperature of the low-temperature liquid lead after the temperature reduction along with the circulation is 400 ℃, and simultaneously carrying out the melting decoppering and the vulcanization decoppering on the low-temperature liquid lead at the bottom of the continuous decoppering furnace return chamber.

(3) Copper metal melted out from low-temperature crude lead at the bottom of the continuous decoppering furnace returning chamber and copper-containing sulfide formed by sulfurizing decoppering float to the liquid surface together, and after the copper metal reacts with the sulfide floating to the liquid surface in the continuous decoppering furnace raw material chamber, an ice copper layer with high copper content is formed.

(4) The bottom of the continuous decoppering furnace returns to the chamber, crude lead with copper content of 0.05 percent is produced through the decoppering by liquation and the copper removal by sulfuration, flows out of the distribution pot through siphoning, and can be cast into an anode plate for the electrolysis process.

(5) Controlling the temperature of an upper molten pool in the continuous copper removing furnace at 1100-1250 ℃, and discharging the copper matte from the copper matte port when the thickness of the copper matte layer on the liquid surface is more than 25 cm. The composition of the matte was analyzed as follows: cu: 66%, S: 21%, Na: 6.7%, Pb: 3% and the others are impurities.

Example two

The lead bullion in this example had the following composition: pb: 97.9%, Cu: 0.5%, S: 0.1%, As: 0.3%, Sb: 0.5 percent of the total weight of the liquid lead bullion, and the balance of impurities, wherein the total weight of the liquid lead bullion is 100 t. Pyrite (containing 40% of sulfur) is used as a novel decoppering agent, and the total consumption of the pyrite is 0.1 t.

(1) 0.01t of pyrite is added into a continuous decoppering furnace raw material chamber along with high-temperature liquid crude lead with the temperature of more than 800 ℃ through a lead inlet of the continuous decoppering furnace, and reacts with high-melting-point substances such as metallic copper, yellow slag and the like separated out by cooling to generate sulfide with relatively low melting point and specific gravity so as to reduce the generation of furnace accretion, and the sulfide is firstly dissolved into the crude lead and then floats to the liquid surface.

(2) And adding the low-temperature liquid lead with the temperature of 420 ℃ after the rest 0.09t of pyrite is cooled along with circulation into a return chamber of the continuous decoppering furnace through a return channel, and simultaneously carrying out liquation decoppering and sulfidization decoppering on the low-temperature liquid lead at the bottom of the return chamber of the continuous decoppering furnace.

(3) Copper metal melted out from low-temperature crude lead at the bottom of the continuous decoppering furnace returning chamber and copper-containing sulfide formed by sulfurizing decoppering float to the liquid surface together, and after the copper metal reacts with the sulfide floating to the liquid surface in the continuous decoppering furnace raw material chamber, an ice copper layer with high copper content is formed.

(4) The bottom of the continuous decoppering furnace returning chamber is subjected to liquation decoppering and sulfuration decoppering to produce crude lead with copper content of 0.06%, and the crude lead flows out of the distribution pot through siphoning and can be cast into an anode plate for an electrolysis process.

(5) Controlling the temperature of an upper molten pool in the continuous copper removing furnace at 1100-1250 ℃, and discharging the copper matte from the copper matte port when the thickness of the copper matte layer on the liquid surface is more than 20 cm. The composition of the matte was analyzed as follows: cu: 70%, S: 19.5%, Fe: 4%, Pb: 4.5%, and the others are impurities.

It is worth to say that when the temperature of the liquid crude lead is less than or equal to 800 ℃, the Cu content is less than or equal to 0.5 percent, the As + Sb content is less than or equal to 0.8 percent, and the flow rate of the crude lead is less than or equal to 1.5t/min, the weight of the novel decoppering agent added into the raw material chamber of the continuous decoppering furnace along with the crude lead can be gradually reduced until the decoppering agent is not added.

EXAMPLE III

The lead bullion in this example had the following composition: pb: 96.2%, Cu: 1.5%, S: 0.2%, As: 0.7%, Sb: 1.3 percent of lead, and the balance of impurities, wherein the total weight of the liquid lead bullion is 100 t. The novel decoppering agent is 0.81t in total weight and is prepared by mixing pyrite and sodium sulfide according to the mass ratio of 1: 1.

(1) 0.243t of novel decoppering agent is added into a continuous decoppering furnace raw material chamber along with high-temperature liquid crude lead with the temperature of more than 800 ℃ through a lead inlet of the continuous decoppering furnace, and reacts with high-melting-point substances such as metallic copper, yellow slag and the like precipitated by cooling to generate sulfide with relatively low melting point and specific gravity so as to reduce the generation of furnace accretion, and the sulfide is firstly dissolved into the crude lead and then floats to the liquid surface.

(2) And adding the residual 0.567t of the novel decoppering agent into a return chamber of the continuous decoppering furnace through a return channel, wherein the temperature of the low-temperature liquid lead after the circulation cooling is 390 ℃, and the low-temperature liquid lead is subjected to liquation decoppering and sulfuration decoppering simultaneously at the bottom of the return chamber of the continuous decoppering furnace.

(3) Copper metal melted out from low-temperature crude lead at the bottom of the continuous decoppering furnace returning chamber and copper-containing sulfide formed by sulfurizing decoppering float to the liquid surface together, and after the copper metal reacts with the sulfide floating to the liquid surface in the continuous decoppering furnace raw material chamber, an ice copper layer with high copper content is formed.

(4) The bottom of the continuous decoppering furnace returning chamber is subjected to liquation decoppering and sulfuration decoppering to produce crude lead containing 0.03% of copper, and the crude lead flows out of the distribution pot through siphoning and can be cast into an anode plate for an electrolysis process.

(5) Controlling the temperature of an upper molten pool in the continuous copper removing furnace at 1100-1250 ℃, and discharging the copper matte from the copper matte port when the thickness of the copper matte layer on the liquid surface is more than 30 cm. The composition of the matte was analyzed as follows: cu: 62%, S: 21.5%, Fe: 4.5%, Na: 5.5%, Pb: 5%, and the others are impurities.

The above-mentioned embodiments are merely preferred embodiments of the present invention, which are merely illustrative and not restrictive, and it should be understood that other embodiments may be easily made by those skilled in the art by replacing or changing the technical contents disclosed in the specification, and therefore, all changes and modifications that are made on the principle of the present invention should be included in the scope of the claims of the present invention.