A method for obtaining crude copper by one-step smelting of chalcocite.

Abstract

This invention discloses a one-step method for smelting chalcocite to obtain crude copper, comprising the following steps: adding chalcocite, flux, and reducing agent to a smelting furnace, and reacting fully under combustion-supported gas conditions to obtain smelting furnace crude copper and smelting slag; adding the slag to be depleted, fuel, flux, sulfiding agent, and reducing agent to a slag depletion furnace, and reacting fully under combustion-supported gas conditions to obtain copper-iron alloy and depleted slag; adding the copper-iron alloy, fuel, and flux to a deep-blown furnace, and reacting fully under combustion-supported gas conditions to obtain deep-blown furnace crude copper and blowing slag. This invention employs a one-step direct smelting of chalcocite to obtain crude copper, with the resulting smelting slag undergoing a slag depletion process, reducing smelting costs, improving smelting efficiency, and ensuring copper recovery rate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chalcocite smelting, and particularly relates to a method for smelting chalcocite to obtain crude copper by one-step method. BACKGROUND

[0002] The smelting process of copper is divided into two types of fire method and wet method, and the fire method dominates. The fire smelting process generally includes smelting, blowing, fire refining and electrolytic refining processes. The process of producing crude copper from copper concentrate generally includes two steps, the first step is smelting and making copper matte, and the second step is blowing the copper matte to produce crude copper. The copper concentrate smelting process includes flash smelting process and oxygen-enriched bath smelting process. The oxygen-enriched bath smelting process includes top blowing smelting process (self-heating furnace top blowing smelting, Mitsubishi method and top blowing submerged smelting, etc.), side blowing smelting process (Vanakof furnace, Baiyin furnace, Jinfeng furnace, etc.), bottom blowing smelting process. The copper matte blowing process includes P-S converter blowing process, flash blowing process, top blowing process (Osmeite blowing method, Isa method, Mitsubishi method, multi-gun top blowing method, etc.), and bottom blowing continuous blowing process. Chalcocite concentrate contains more than 40% copper, less than 5% iron, 10-18% sulfur, and 5-20% silicon dioxide. The sulfur content in the chemical composition is low, and if smelting is performed, additional fuel is needed, and sulfur elements also need to be supplemented, but the sulfur elements will be removed in the blowing stage, and the low iron content also makes it difficult to obtain low melting point iron olivine slag type in the smelting stage. Therefore, chalcocite concentrate is not suitable for direct smelting by the conventional “smelting + blowing” two-step operation mode. Chinese patent CN118222846A discloses a chalcocite smelting method, which proposes that the chalcocite concentrate is dried and then sent to a flash furnace to directly obtain crude copper, and the smelting slag is sent to an electric furnace for depletion, which has the problems of low electric furnace efficiency and serious dependence on electric energy. SUMMARY

[0003] The present application aims to at least solve one of the technical problems in the related art to some extent.

[0004] To this end, an embodiment of the present application proposes a method for smelting chalcocite to obtain crude copper by one-step method.

[0005] In a first aspect, the present application proposes a method for smelting chalcocite to obtain crude copper by one-step method, comprising the following steps:

[0006] (1) adding chalcocite, flux and reducing agent into a smelting furnace, and fully reacting under the condition of combustion-supporting gas to obtain smelting furnace crude copper and smelting slag;

[0007] (2) adding the to-be-depleted slag, fuel, flux, sulfurizing agent and reducing agent into a slag depletion furnace, and fully reacting under the condition of combustion-supporting gas to obtain copper-iron alloy and depleted slag;

[0008] (3) adding the copper-iron alloy, fuel and flux into the deep-blast furnace, and fully reacting under the condition of combustion-supporting gas to obtain deep-blast furnace crude copper and blowing slag.

[0009] Further, the step (2) adopts a two-stage depletion method, and the slag depletion furnace comprises a first-stage slag depletion furnace and a second-stage slag depletion furnace, wherein the to-be-depleted slag, fuel, flux, sulfuration agent and reducing agent fully react under the condition of combustion-supporting gas in the first-stage slag depletion furnace to obtain slag-depletion-furnace crude copper and depleted initial slag, and the depleted initial slag, fuel, flux, sulfuration agent and reducing agent fully react under the condition of combustion-supporting gas in the second-stage slag depletion furnace to obtain copper-iron alloy and depleted slag.

[0010] Further, the to-be-depleted slag comprises the smelting slag, the blowing slag and the depleted initial slag.

[0011] Further, the method further comprises (4) sending the crude copper into an anode furnace for refining, wherein the crude copper comprises the smelting-furnace crude copper, the deep-blast-furnace crude copper and the slag-depletion-furnace crude copper.

[0012] Further, the method further comprises sending the flue gas generated in steps (1)-(4) to a flue gas treatment system.

[0013] Further, the amount of the flux added in step (1) is 0-6% of the mass of the chalcocite.

[0014] Further, the amount of the sulfuration agent added in step (2) is 0-20% of the mass of the to-be-depleted slag.

[0015] Further, the amount of the reducing agent added in step (1) is 0-2% of the mass of the chalcocite.

[0016] Further, the mass content of copper in the smelting slag is 15%-30%.

[0017] Further, in the copper-iron alloy, Fe≤10% and S≤10% by mass content.

[0018] Further, the mass content of copper in the depleted initial slag is 5%-8%.

[0019] Further, the mass content of copper in the depleted slag is 0.2%-1%.

[0020] Further, the flux comprises one or both of limestone and quartz stone.

[0021] Further, the reducing agent comprises solid-state carbon-containing substances.

[0022] Further, the solid-state carbon-containing substances comprise one or more of coal, coke and wood.

[0023] Further, the sulfidizing agent comprises one or more of sulfur, sulfate, copper concentrate, pyrite.

[0024] Further, the combustion-supporting gas comprises air or oxygen-enriched air with an oxygen content of 20% to 100%.

[0025] Further, the reaction temperature in step (1) is 1150 to 1400 DEG C.

[0026] Further, the reaction temperature in step (2) is 1300 to 1600 DEG C.

[0027] Further, the smelting furnace comprises a side-blown furnace.

[0028] Further, the slag-lean furnace comprises a side-blown furnace or a multi-functional metallurgical furnace.

[0029] Further, the deep-blown furnace comprises one of a PS converter, a flash smelting furnace, a top-blown converter, and a bottom-blown continuous converter.

[0030] Further, the first-stage slag-lean furnace comprises a side-blown furnace or a multi-functional metallurgical furnace.

[0031] Further, the second-stage slag-lean furnace comprises a side-blown furnace or a multi-functional metallurgical furnace.

[0032] Compared with the prior art, the present application has the following advantages:

[0033] The present application directly smelts chalcocite to obtain crude copper by one-step method, and the smelting slag is subjected to a slag-lean process, thereby reducing the smelting cost, improving the smelting efficiency, and ensuring the copper recovery rate. BRIEF DESCRIPTION OF DRAWINGS

[0034] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the accompanying drawings, in which:

[0035] Figure 1 The present application is a flowchart of the slag-lean process when a one-stage lean process is adopted.

[0036] Figure 2 The present application is a flowchart of the slag-lean process when a two-stage lean process is adopted. DETAILED DESCRIPTION

[0037] Embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0038] The following description, in conjunction with the accompanying drawings, describes a one-step method for smelting chalcocite to obtain crude copper, as proposed in this invention.

[0039] The method for obtaining crude copper by one-step smelting of chalcocite according to the present invention includes the following steps:

[0040] (1) Add chalcocite, flux and reducing agent to the smelting furnace and react fully under the conditions of combustion-supporting gas to obtain smelting furnace crude copper and smelting slag;

[0041] (2) Add the slag to be depleted, fuel, flux, sulfiding agent and reducing agent into the slag depletion furnace, and react fully under the conditions of combustion-supporting gas to obtain copper-iron alloy and depleted slag;

[0042] (3) The copper-iron alloy, fuel and flux are added to the deep-blown furnace and reacted fully under the conditions of combustion-supporting gas to obtain deep-blown furnace crude copper and smelting slag;

[0043] (4) The crude copper is sent to the anode furnace for refining;

[0044] (5) Send the flue gas generated in each process to the flue gas treatment system.

[0045] In step (1), chalcocite, solvent, and reducing agent are metered and mixed, then transported to the smelting furnace via a conveying system. At a suitable temperature, they react fully with the combustion-supporting gas blown into the furnace to obtain crude copper and smelting slag. The suitable temperature is 1150~1400℃, and the temperature is maintained within this range by adding materials during the reaction.

[0046] After smelting in a furnace, most of the Cu in the chalcocite concentrate is converted into metallic copper and aggregates to form crude copper. A small portion of Cu enters the smelting slag as metallic inclusions or oxides. All the S is oxidized to SO2 and enters the flue gas, while the Fe is oxidized to FeO or Fe3O4 and combines with flux, SiO2, Al2O3, CaO, and other oxides in the chalcocite concentrate to form the smelting slag. The copper content in the smelting slag is 15%–30%.

[0047] In some embodiments, the flux includes one or both of limestone and quartz.

[0048] The amount of flux added is 0-6% of the mass of chalcocite. When the amount of flux added is within a suitable range, the slag shape of the smelting slag is improved, resulting in better fluidity and a lower melting point. When too much flux is added, the fluidity of the smelting slag will decrease and the melting point will increase, causing the working conditions to deteriorate, energy consumption to increase, and in severe cases, affecting the normal operation of production.

[0049] In some embodiments, the reducing agent comprises a solid carbonaceous substance, which includes one or more of coal, coke, and firewood.

[0050] The amount of reducing agent added is 0-2% of the mass of chalcocite. The amount of reducing agent added within a suitable range reduces the oxygen potential in the smelting slag, thereby reducing the Fe3O4 content and improving the slag type.

[0051] In some embodiments, the combustion-supporting gas includes air or oxygen-enriched air with an oxygen content of 20% to 100%. The combustion-supporting gas is continuously supplied during the reaction. The flow rate of the combustion-supporting gas is 500 Nm³. 3 / t crude copper ~1500Nm 3 / t crude copper.

[0052] In some embodiments, the smelting furnace includes a side-blown furnace.

[0053] Step (2) is the slag depletion process. In some embodiments, such as Figure 1 As shown, the slag depletion process employs a single-stage depletion method. This method involves adding the slag to be depleted, fuel, flux, sulfiding agent, and reducing agent to a slag depletion furnace. Under combustion-supporting gas conditions, the mixture reacts fully to obtain a copper-iron alloy and depleted slag. The copper content in the depleted slag is 0.2% to 1%, meaning the slag to be depleted is directly reduced to a lower copper content range to obtain the copper-iron alloy. The slag depletion furnace includes a side-blown furnace or a multi-functional metallurgical furnace (see Chinese Patent CN116499247A). The sulfiding agent includes one or more of sulfur, sulfate, copper concentrate, and pyrite. The amount of sulfiding agent added is 0-20% of the mass of the slag to be depleted; excessive addition of sulfiding agent will increase production costs. In some embodiments, such as... Figure 2 As shown, the slag depletion process employs a two-stage depletion method. The slag depletion furnace includes a first-stage slag depletion furnace and a second-stage slag depletion furnace. In the first-stage slag depletion furnace, the depleted slag, fuel, flux, and reducing agent react fully to obtain crude copper and initial depleted slag. The copper content in the initial depleted slag is 5%~8%. In the second-stage slag depletion furnace, the initial depleted slag, fuel, flux, and reducing agent react fully to obtain a copper-iron alloy and depleted slag. The depleted slag obtained in the second-stage slag depletion furnace is the final depleted slag, with a copper content of 0.2%~1%. The first-stage slag depletion furnace includes a side-blown furnace or a multi-functional metallurgical furnace (see Chinese Patent CN116499247A), and the second-stage slag depletion furnace also includes a side-blown furnace or a multi-functional metallurgical furnace (see Chinese Patent CN116499247A).

[0054] The advantage of using a single-stage depletion method is that, with good raw materials, only one depletion furnace is needed to fully recover valuable metals from the smelting slag, resulting in low investment costs. The advantage of using a two-stage depletion method is that it can adapt to more complex raw materials and can stably and fully recover valuable metals from the smelting slag.

[0055] The slag to be depleted includes smelting slag produced from smelting chalcocite, blowing slag produced from subsequent copper-iron alloy blowing processes, and initial depleted slag produced in the first stage slag depletion furnace when a two-stage depletion method is adopted.

[0056] In some embodiments, the fuel includes carbonaceous materials, including but not limited to coal, coke, diesel, natural gas, etc.

[0057] Step (3) is the smelting process of the copper-iron alloy. The copper-iron alloy, fuel, and flux are added to the deep-blown furnace and reacted fully under the conditions of combustion-supporting gas. Cu mainly forms crude copper, resulting in deep-blown furnace crude copper. The deep-blown furnace crude copper undergoes a subsequent refining process. Fe is oxidized to FeO and reacts with SiO2 to form slag, which is then depleted. It is understood that the amount of flux and fuel added is determined according to the specific operating conditions.

[0058] In some embodiments, copper-iron alloys may also be sold directly.

[0059] In some embodiments, the deep-blown furnace includes one of the following: PS converter, flash furnace, top-blown furnace (Osmelt furnace, Isafa furnace, Mitsubishi C furnace, multi-lance top-blown furnace), and bottom-blown continuous furnace.

[0060] Step (4) is the refining process of crude copper, which involves sending the crude copper produced in each production process into the anode furnace for refining. The crude copper includes smelting furnace crude copper produced in the smelting process of chalcocite, deep blowing furnace crude copper produced in the blowing process of copper-iron alloy, and slag depletion furnace crude copper produced when the two-stage depletion method is adopted.

[0061] Step (5) is the flue gas treatment process, which involves sending the flue gas generated from the chalcocite smelting process, slag depletion process, and copper-iron alloy blowing process to the flue gas treatment system for treatment.

[0062] The method of the present invention will be described below with reference to specific embodiments.

[0063] Example 1

[0064] 100 t / h of chalcocite concentrate, 1.3 t / h of flux lime, and 2.0 t / h of reducing anthracite are separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) is introduced into the furnace, and the mixture undergoes a full reaction at 1250–1350 °C to produce 30 t / h of crude copper and 54 t / h of smelting slag containing 15% copper. The chalcocite concentrate contains 40% copper, 15% iron, 8%–20% sulfur, and 10%–30% silica.

[0065] 54 t / h of smelting slag, 4.5 t / h of blowing slag, and metered 2 t / h of anthracite (reducing agent and fuel), 7.5 t / h of lime (flux), 2 t / h of sulfur (sulfiding agent), and 60% oxygen-enriched air are fully reacted in a multi-functional metallurgical furnace (slag depletion furnace) at 1300~1400℃ to obtain 10 t / h of copper-iron alloy containing 7% iron and 8% sulfur, and 50 t / h of depleted slag containing 0.5% copper. The flow rate of the oxygen-enriched air is 5000 Nm³. 3 / h.

[0066] A 10 t / h copper-iron alloy is reacted with metered 0.5 t / h anthracite (fuel), 1.5 t / h quartz (flux), and 70% oxygen-enriched air in a bottom-blown furnace (deep-blown furnace) at 1200~1250℃ to produce 8 t / h crude copper and 4.5 t / h smelting slag. The flow rate of the oxygen-enriched air is 1500 Nm³. 3 / h.

[0067] The crude copper obtained from chalcocite concentrate smelting and the crude copper obtained from copper-iron alloy blowing are sent to an anode furnace for refining. The flue gas generated in each process is sent to a flue gas treatment system for treatment.

[0068] Example 2

[0069] 100 t / h of chalcocite concentrate, 2.8 t / h of flux lime, and 2.0 t / h of reducing anthracite are separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) is introduced into the furnace, and the mixture undergoes a full reaction at 1250–1350 °C to produce 30 t / h of crude copper and 55 t / h of smelting slag containing 15% copper. The chalcocite concentrate contains 40% copper, 15% iron, 8%–20% sulfur, and 10%–30% silica.

[0070] 55 t / h of smelting slag, 4.5 t / h of blowing slag, and metered 2 t / h of anthracite (reducing agent and fuel), 6.1 t / h of lime (flux), 2 t / h of sulfur (sulfiding agent), and 60% oxygen-enriched air are fully reacted in a multi-functional metallurgical furnace (slag depletion furnace) at 1300~1400℃ to obtain 10 t / h of copper-iron alloy containing 7% iron and 8% sulfur, and 50 t / h of depleted slag containing % copper. The flow rate of the oxygen-enriched air is 4900 Nm³. 3 / h.

[0071] A 10 t / h copper-iron alloy is reacted with metered 0.5 t / h anthracite (fuel), 1.5 t / h quartz (flux), and 70% oxygen-enriched air in a bottom-blown furnace (deep-blown furnace) at 1200~1250℃ to produce 8 t / h crude copper and 4.5 t / h smelting slag. The flow rate of the oxygen-enriched air is 1500 Nm³.3 / h.

[0072] The crude copper obtained from chalcocite concentrate smelting and the crude copper obtained from copper-iron alloy blowing are sent to an anode furnace for refining. The flue gas generated in each process is sent to a flue gas treatment system for treatment.

[0073] Example 3

[0074] 100 t / h of chalcocite concentrate, 5.4 t / h of flux lime, and 2.0 t / h of reducing anthracite are metered and mixed separately, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) is introduced into the furnace, and the mixture undergoes a full reaction at 1250–1350 °C to produce 30 t / h of crude copper and 57 t / h of smelting slag containing 15% copper. The chalcocite concentrate contains 40% copper, 15% iron, 8%–20% sulfur, and 10%–30% silica.

[0075] 57 t / h of smelting slag, 4.5 t / h of blowing slag, and metered 2 t / h of anthracite (reducing agent and fuel), 1.5 t / h of lime (flux), 2 t / h of sulfur (sulfiding agent), and 60% oxygen-enriched air are fully reacted in a multi-functional metallurgical furnace (slag depletion furnace) at 1300~1400℃ to obtain 10 t / h of copper-iron alloy containing 7% iron and 8% sulfur, and 50 t / h of depleted slag containing 0.5% copper. The flow rate of the oxygen-enriched air is 5500 Nm³. 3 / h.

[0076] A 10 t / h copper-iron alloy is reacted with metered 0.5 t / h anthracite (fuel), 1.5 t / h quartz (flux), and 70% oxygen-enriched air in a bottom-blown furnace (deep-blown furnace) at 1200~1250℃ to produce 8 t / h of crude copper and 4.5 t / h of smelting slag. The flow rate of the oxygen-enriched air is 1500 Nm³. 3 / h.

[0077] The crude copper obtained from chalcocite concentrate smelting and the crude copper obtained from copper-iron alloy blowing are sent to an anode furnace for refining. The flue gas generated in each process is sent to a flue gas treatment system for treatment.

[0078] Example 4

[0079] 100 t / h of chalcocite concentrate, 1.3 t / h of flux lime, and 1 t / h of reducing anthracite are separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) is introduced into the furnace, and the mixture undergoes a full reaction at 1250–1350 °C to produce 30 t / h of crude copper and 55 t / h of smelting slag containing 14.7% copper. The chalcocite concentrate contains 40% copper, 15% iron, 8%–20% sulfur, and 10%–30% silica.

[0080] 55 t / h of smelting slag, 4.5 t / h of blowing slag, and metered 3.2 t / h of anthracite (reducing agent and fuel), 7.5 t / h of lime (flux), 2 t / h of sulfur (sulfiding agent), and 60% oxygen-enriched air are fully reacted in a multi-functional metallurgical furnace (slag depletion furnace) at 1300~1400℃ to obtain 10 t / h of copper-iron alloy containing 7% iron and 8% sulfur, and 50 t / h of depleted slag containing 0.5% copper. The flow rate of the oxygen-enriched air is 6500 Nm³. 3 / h.

[0081] A 10 t / h copper-iron alloy is reacted with metered 0.5 t / h anthracite (fuel), 1.5 t / h quartz (flux), and 70% oxygen-enriched air in a bottom-blown furnace (deep-blown furnace) at 1200~1250℃ to produce 8 t / h crude copper and 4.5 t / h smelting slag. The flow rate of the oxygen-enriched air is 1500 Nm³. 3 / h.

[0082] The crude copper obtained from chalcocite concentrate smelting and the crude copper obtained from copper-iron alloy blowing are sent to an anode furnace for refining. The flue gas generated in each process is sent to a flue gas treatment system for treatment.

[0083] Example 5

[0084] 100 t / h of chalcocite concentrate, 1.3 t / h of flux lime, and 1.50 t / h of reducing anthracite are separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) is introduced into the furnace, and the mixture undergoes a full reaction at 1250–1350 °C to produce 30 t / h of crude copper and 53 t / h of smelting slag containing 15.3% copper. The chalcocite concentrate contains 40% copper, 15% iron, 8%–20% sulfur, and 10%–30% silica.

[0085] 53 t / h of smelting slag, 4.5 t / h of blowing slag, and metered 1.8 t / h of anthracite (reducing agent and fuel), 7.5 t / h of lime (flux), 2 t / h of sulfur (sulfiding agent), and 60% oxygen-enriched air are fully reacted in a multi-functional metallurgical furnace (slag depletion furnace) at 1300~1400℃ to obtain 10 t / h of copper-iron alloy containing 7% iron and 8% sulfur, and 48 t / h of depleted slag containing 0.5% copper. The flow rate of the oxygen-enriched air is 5000 Nm³. 3 / h.

[0086] A 10 t / h copper-iron alloy is reacted with metered 0.5 t / h anthracite (fuel), 1.5 t / h quartz (flux), and 70% oxygen-enriched air in a bottom-blown furnace (deep-blown furnace) at 1200~1250℃ to produce 8 t / h crude copper and 4.5 t / h smelting slag. The flow rate of the oxygen-enriched air is 1500 Nm³. 3 / h.

[0087] The crude copper obtained from chalcocite concentrate smelting and the crude copper obtained from copper-iron alloy blowing are sent to an anode furnace for refining. The flue gas generated in each process is sent to a flue gas treatment system for treatment.

[0088] Example 6

[0089] 110 t / h of chalcocite concentrate, 2.4 t / h of flux lime, and 1.5 t / h of reducing agent coke were separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) was introduced into the side-blown furnace, and the mixture underwent a complete reaction at 1250–1350 °C to form 30 t / h of crude copper and 65 t / h of smelting slag containing 25% copper. The composition of the chalcocite was the same as in Example 1.

[0090] A 65 t / h smelting slag and a 2 t / h blowing slag are reacted with metered 1 t / h coke (reducing agent), 6 t / h lime (flux), 10 t / h pyrite (sulfiding agent), natural gas (fuel), and 65% oxygen-enriched air in a side-blown furnace (first-stage slag depletion furnace) at 1250~1350℃ to obtain 15 t / h crude copper and 60 t / h depleted primary slag containing 6% copper. The flow rate of the oxygen-enriched air is 6000 Nm³. 3 / h; natural gas flow rate is 2400 Nm 3 / h.

[0091] A 60 t / h capacity of primary slag depletion is reacted with metered 0.2 t / h coke (reducing agent), 0.5 t / h lime (flux), 2 t / h pyrite (sulfiding agent), natural gas (fuel), and 65% oxygen-enriched air in a side-blown furnace (second-stage slag depletion furnace) at 1300-1400℃ to produce a 4.8 t / h capacity of copper-iron alloy containing 5% iron and 6% sulfur, and a 55 t / h capacity of final slag depletion containing 0.3% copper. The oxygen-enriched air flow rate is 1250 Nm³. 3 / h; natural gas flow rate is 400 Nm 3 / h.

[0092] A 4.8 t / h copper-iron alloy is reacted with a metered 1 t / h quartz (flux), natural gas (fuel), and oxygen-enriched air (65% oxygen content) in a bottom-blown furnace (deep-blown furnace) at 1250-1300℃ to obtain crude copper and smelting slag. The smelting slag undergoes a depletion process, which will not be detailed here. The flow rate of the oxygen-enriched air is 2000 Nm³. 3 / h; natural gas flow rate is 450 Nm 3 / h.

[0093] The crude copper obtained from chalcocite concentrate smelting, the crude copper obtained from copper-iron alloy blowing, and the crude copper obtained from the smelting slag depletion process are sent to the anode furnace for refining. The flue gas generated in each process is sent to the flue gas treatment system for treatment.

[0094] Example 7

[0095] 110 t / h of chalcocite concentrate, 2.4 t / h of flux lime, and 1.5 t / h of reducing agent coke were separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) was introduced into the side-blown furnace, and the mixture underwent a complete reaction at 1250–1350 °C to form 30 t / h of crude copper and 65 t / h of smelting slag containing 25% copper. The composition of the chalcocite was the same as in Example 1.

[0096] A 65 t / h smelting slag and a 2 t / h blowing slag are reacted with metered 1 t / h coke (reducing agent), 6 t / h lime (flux), 10 t / h pyrite (sulfiding agent), natural gas (fuel), and 65% oxygen-enriched air in a side-blown furnace (first-stage slag depletion furnace) at 1250~1350℃ to obtain 15 t / h crude copper and 60 t / h depleted primary slag containing 6% copper. The flow rate of the oxygen-enriched air is 6000 Nm³. 3 / h; natural gas flow rate is 2400 Nm 3 / h.

[0097] A 60 t / h capacity of depleted primary slag is reacted with metered 0.2 t / h coke (reducing agent), 0.5 t / h lime (flux), 5 t / h pyrite (sulfiding agent), natural gas (fuel), and 65% oxygen-enriched air in a side-blown furnace (second-stage slag depletion furnace) at 1300-1400℃ to obtain 5 t / h of copper-iron alloy containing 5% iron and 6% sulfur, and 56 t / h of depleted final slag containing 0.3% copper. The oxygen-enriched air flow rate is 1250 Nm³. 3 / h; natural gas flow rate is 400 Nm 3 / h.

[0098] A 5t / h copper-iron alloy is reacted with a metered 1t / h quartz (flux), natural gas (fuel), and oxygen-enriched air (65% oxygen content) in a bottom-blown furnace (deep-blown furnace) at 1250~1300℃ to obtain crude copper and smelting slag. The smelting slag undergoes a depletion process, which will not be detailed here. The flow rate of the oxygen-enriched air is 2000 Nm³. 3 / h; natural gas flow rate is 450 Nm 3 / h.

[0099] The crude copper obtained from chalcocite concentrate smelting, the crude copper obtained from copper-iron alloy blowing, and the crude copper obtained from the smelting slag depletion process are sent to the anode furnace for refining. The flue gas generated in each process is sent to the flue gas treatment system for treatment.

[0100] Example 8

[0101] 110 t / h of chalcocite concentrate, 2.4 t / h of flux lime, and 1.5 t / h of reducing agent coke were separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) was introduced into the side-blown furnace, and the mixture underwent a complete reaction at 1250–1350 °C to form 30 t / h of crude copper and 65 t / h of smelting slag containing 25% copper. The composition of the chalcocite was the same as in Example 1.

[0102] A 65t / h smelting slag and a 2t / h blowing slag are reacted with metered 5t / h coke (reducing agent), 6t / h lime (flux), natural gas (fuel), and 65% oxygen-enriched air in a side-blown furnace (first-stage slag depletion furnace) at 1250~1350℃ to produce 15t / h crude copper and 60t / h depleted primary slag containing 6% copper. The flow rate of the oxygen-enriched air is 8000 Nm³. 3 / h; natural gas flow rate is 2400 Nm 3 / h.

[0103] A 60 t / h capacity of primary slag depletion is reacted with metered 0.2 t / h coke (reducing agent), 0.5 t / h lime (flux), 2 t / h pyrite (sulfiding agent), natural gas (fuel), and 65% oxygen-enriched air in a side-blown furnace (second-stage slag depletion furnace) at 1300-1400℃ to produce a 4.8 t / h capacity of copper-iron alloy containing 5% iron and 6% sulfur, and a 55 t / h capacity of final slag depletion containing 0.3% copper. The oxygen-enriched air flow rate is 1250 Nm³. 3 / h; natural gas flow rate is 400 Nm 3 / h.

[0104] A 4.8 t / h copper-iron alloy is reacted with a metered 1 t / h quartz (flux), natural gas (fuel), and oxygen-enriched air (65% oxygen content) in a bottom-blown furnace (deep-blown furnace) at 1250-1300℃ to obtain crude copper and smelting slag. The smelting slag undergoes a depletion process, which will not be detailed here. The flow rate of the oxygen-enriched air is 2000 Nm³. 3 / h; natural gas flow rate is 450 Nm 3 / h.

[0105] The crude copper obtained from chalcocite concentrate smelting, the crude copper obtained from copper-iron alloy blowing, and the crude copper obtained from the smelting slag depletion process are sent to the anode furnace for refining. The flue gas generated in each process is sent to the flue gas treatment system for treatment.

[0106] Comparative Example 1

[0107] 100 t / h of chalcocite concentrate, 10 t / h of flux lime, and 2.0 t / h of reducing anthracite are separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) is introduced into the furnace, and the mixture undergoes a full reaction at 1250–1350 °C to produce 30 t / h of crude copper and 60 t / h of smelting slag containing 14% copper. The chalcocite concentrate contains 40% copper, 15% iron, 8%–20% sulfur, and 10%–30% silica.

[0108] A multi-functional metallurgical furnace (slag depletion furnace) is used to fully react 60 t / h of smelting slag, 4.5 t / h of blowing slag, 3 t / h of metered anthracite (reducing agent and fuel), 2 t / h of sulfur (sulfiding agent), and 60% oxygen-enriched air at 1300~1400℃ to produce 10 t / h of copper-iron alloy containing 7% iron and 8% sulfur, and 52 t / h of depleted slag containing 0.5% copper. The flow rate of the oxygen-enriched air is 6000 Nm³. 3 / h.

[0109] A 10 t / h copper-iron alloy is reacted with metered 0.5 t / h anthracite (fuel), 1.5 t / h quartz (flux), and 70% oxygen-enriched air in a bottom-blown furnace (deep-blown furnace) at 1200~1250℃ to produce 8 t / h crude copper and 4.5 t / h smelting slag. The flow rate of the oxygen-enriched air is 1500 Nm³. 3 / h.

[0110] The crude copper obtained from chalcocite concentrate smelting and the crude copper obtained from copper-iron alloy blowing are sent to an anode furnace for refining. The flue gas generated in each process is sent to a flue gas treatment system for treatment.

[0111] Comparative Example 2

[0112] 100 t / h of chalcocite concentrate, 1.3 t / h of flux lime, and 5 t / h of reducing anthracite are separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) is introduced into the furnace, and the mixture undergoes a full reaction at 1250–1350 °C to produce 30 t / h of crude copper and 54 t / h of smelting slag containing 15% copper. The chalcocite concentrate contains 40% copper, 15% iron, 8%–20% sulfur, and 10%–30% silica.

[0113] 54 t / h of smelting slag, 4.5 t / h of blowing slag, and metered 2 t / h of anthracite (reducing agent and fuel), 7.5 t / h of lime (flux), 2 t / h of sulfur (sulfiding agent), and 60% oxygen-enriched air are fully reacted in a multi-functional metallurgical furnace (slag depletion furnace) at 1300~1400℃ to obtain 10 t / h of copper-iron alloy containing 7% iron and 8% sulfur, and 50 t / h of depleted slag containing 0.5% copper. The flow rate of the oxygen-enriched air is 5000 Nm³. 3 / h.

[0114] A 10 t / h copper-iron alloy is reacted with metered 0.5 t / h anthracite (fuel), 1.5 t / h quartz (flux), and 70% oxygen-enriched air in a bottom-blown furnace (deep-blown furnace) at 1200~1250℃ to produce 8 t / h crude copper and 4.5 t / h smelting slag. The flow rate of the oxygen-enriched air is 1500 Nm³. 3 / h.

[0115] The crude copper obtained from chalcocite concentrate smelting and the crude copper obtained from copper-iron alloy blowing are sent to an anode furnace for refining. The flue gas generated in each process is sent to a flue gas treatment system for treatment.

[0116] Comparative Example 3

[0117] 110 t / h of chalcocite concentrate, 2.4 t / h of flux lime, and 1.5 t / h of reducing agent coke were separately metered and mixed, then conveyed to a side-blown furnace via a conveying system. Oxygen-enriched air (80% oxygen content) was introduced into the side-blown furnace, and the mixture underwent a complete reaction at 1250–1350 °C to form 30 t / h of crude copper and 65 t / h of smelting slag containing 25% copper. The composition of the chalcocite was the same as in Example 1.

[0118] A 65 t / h smelting slag, a 2 t / h blowing slag, and metered 2 t / h coke (reducing agent), 6 t / h lime (flux), 10 t / h pyrite (sulfiding agent), natural gas (fuel), and 65% oxygen-enriched air are fully reacted in a side-blown furnace (first-stage slag depletion furnace) at 1250~1350℃ to obtain 15 t / h crude copper and 60 t / h depleted primary slag containing 6% copper. The flow rate of the oxygen-enriched air is 6000 Nm³. 3 / h; natural gas flow rate is 2400 Nm 3 / h.

[0119] A 60 t / h capacity of depleted primary slag is reacted with metered 0.2 t / h coke (reducing agent), 0.5 t / h lime (flux), 15 t / h pyrite (sulfiding agent), natural gas (fuel), and 65% oxygen-enriched air in a side-blown furnace (second-stage slag depletion furnace) at 1300-1400℃ to obtain a 4 t / h capacity of copper-iron alloy containing 5% iron and 6% sulfur, and a 60 t / h capacity of depleted final slag containing 0.3% copper. The oxygen-enriched air flow rate is 1500 Nm³. 3 / h; natural gas flow rate is 500 Nm 3 / h.

[0120] A 4t / h copper-iron alloy is reacted with a metered 1t / h quartz (flux), natural gas (fuel), and oxygen-enriched air (65% oxygen content) in a bottom-blown furnace (deep-blown furnace) at 1250~1300℃ to obtain crude copper and smelting slag. The smelting slag undergoes a depletion process, which will not be detailed here. The flow rate of the oxygen-enriched air is 1500 Nm³. 3 / h; natural gas flow rate is 350 Nm 3 / h.

[0121] The crude copper obtained from chalcocite concentrate smelting, the crude copper obtained from copper-iron alloy blowing, and the crude copper obtained from the smelting slag depletion process are sent to the anode furnace for refining. The flue gas generated in each process is sent to the flue gas treatment system for treatment.

[0122] The crude copper prepared in Examples 1 to 8 of this invention conforms to the standard of "Crude Copper" (YS / T 70-2015). From a practical production perspective, the process of obtaining crude copper from copper concentrate through one-step smelting has been applied in three smelters, and side-blown furnaces have also been widely used in copper smelting production. The multi-functional furnace mentioned in this invention has also successfully achieved the expected results in the slag depletion process of nickel smelting. From a theoretical research perspective, the process mentioned in this invention conforms to basic metallurgical principles, and its one-step smelting process for obtaining crude copper has been verified by experiments. Therefore, the process mentioned in this invention is feasible.

[0123] The excessive amounts of flux (Comparative Example 1), reducing agent (Comparative Example 2), and sulfiding agent (Comparative Example 3) in Comparative Examples 1-3 did not yield better technical indicators. Instead, they increased the quality of the hot melt in the system (the amount of smelting slag and depleted slag in Comparative Example 1 and the amount of depleted final slag in Comparative Example 3). This will further lead to energy waste and loss of valuable elements, resulting in economic losses. In Comparative Example 2, the excessive amount of reducing agent not only caused waste of materials and energy but also generated more flue gas in the system, reducing the SO2 concentration in the flue gas. This is not conducive to the stable operation of the flue gas system and the normal production of the acid production system.

[0124] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms may refer to different embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0125] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0126] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A process for smelting chalcocite to obtain crude copper in a single step, characterized in that, The method comprises the following steps: (1) adding chalcocite, flux and reducing agent into a smelting furnace, and fully reacting under the condition of combustion-supporting gas to obtain smelting furnace crude copper and smelting slag; (2) adding to-be-leaned slag, fuel, flux, sulfuration agent and reducing agent into a slag-leaner furnace, and fully reacting under the condition of combustion-supporting gas to obtain copper-iron alloy and lean slag; (3) adding the copper-iron alloy, fuel and flux into a deep-blowing furnace, and fully reacting under the condition of combustion-supporting gas to obtain deep-blowing furnace crude copper and blowing slag, The step (2) adopts two-stage lean method, and the slag-leaner furnace comprises a first-stage slag-leaner furnace and a second-stage slag-leaner furnace, the to-be-leaned slag, fuel, flux, sulfuration agent and reducing agent fully react under the condition of combustion-supporting gas in the first-stage slag-leaner furnace to obtain slag-leaner furnace crude copper and lean initial slag, the lean initial slag, fuel, flux, sulfuration agent and reducing agent fully react under the condition of combustion-supporting gas in the second-stage slag-leaner furnace to obtain copper-iron alloy and lean slag, the to-be-leaned slag comprises the smelting slag, the blowing slag and the lean initial slag, the reducing agent comprises solid-state carbon-containing substance, and the copper mass content in the lean initial slag is 5% to 8%; and / or, the copper mass content in the lean slag is 0.2% to 1%.

2. The method of claim 1, wherein, The method further comprises (4) sending crude copper into an anode furnace for refining, wherein the crude copper comprises the smelting furnace crude copper, the deep-blowing furnace crude copper and the slag-leaner furnace crude copper.

3. The method of claim 2, wherein, The method further comprises sending flue gas generated in steps (1) to (4) to a flue gas treatment system.

4. The method of claim 1, wherein, In the step (1), the flux is added in an amount of 0 to 6% of the mass of the chalcocite; and / or, in the step (1), the reducing agent is added in an amount of 0 to 2% of the mass of the chalcocite; and / or, in the step (2), the sulfuration agent is added in an amount of 0 to 20% of the mass of the to-be-leaned slag.

5. The method of claim 1, wherein, The smelting slag has a copper mass content of 15% to 30%; and / or, the copper-iron alloy has Fe≤10% and S≤10% in terms of mass content; and / or, the reaction temperature in the step (1) is 1150 to 1400 ℃; and / or, the reaction temperature in the step (2) is 1300 to 1600 ℃.

6. The method of claim 1, wherein, The flux comprises one or both of limestone or quartz stone; and / or, the solid-state carbon-containing substance comprises one or more of coal, coke or wood; and / or, the sulfuration agent comprises one or more of sulfur, sulfate, copper concentrate or pyrite; and / or, the combustion-supporting gas comprises air or oxygen-enriched air with an oxygen content of 20% to 100%.

7. The method of claim 1, wherein, The smelting furnace comprises a side-blown furnace; and / or, the slag-leaner furnace comprises a side-blown furnace or a multifunctional metallurgical furnace; and / or, the deep-blowing furnace comprises one of a PS converter, a flash smelting furnace, a top-blown converter or a bottom-blown continuous converter; and / or, the first-stage slag-leaner furnace comprises a side-blown furnace or a multifunctional metallurgical furnace; and / or, the second-stage slag-leaner furnace comprises a side-blown furnace or a multifunctional metallurgical furnace.

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