Method for smelting copper by reducing copper sulfide ore through hydrogen

Abstract

The method comprises the following steps: uniformly mixing copper sulfide concentrate powder with a binder and water, pelletizing, drying, adding into an electric arc furnace, heating to 1500-1600 DEG C, melting to form a molten pool, and introducing hydrogen into the molten pool; in the reaction process, pellets are continuously added into the electric furnace, and hydrogen is introduced into the electric furnace. And after the molten metal in the electric arc furnace reaches a certain amount and the pellets added into the furnace completely react, hydrogen feeding is stopped, oxygen is fed into the molten metal, iron in the molten metal is oxidized into FeO, and the FeO enters slag. And if the iron content in the molten metal is less than 0.5%, stopping blowing oxygen, pouring out slag for extracting iron, casting copper into an electrode plate, and carrying out anode refining to prepare electrolytic copper. And the slag is poured into another electric arc furnace, hydrogen is blown into a molten pool, a chemical reaction is carried out to obtain FeO + H2 = Fe + H2O, the obtained molten iron is used for steelmaking, and smoke heat is used for power generation.

Description

Technical Field

[0001] The present invention relates to the field of metallurgy, and in particular to a method for smelting copper by reducing copper sulfide ore with hydrogen. Background Art

[0002] There are several main methods for pyrometallurgical copper smelting using copper sulfide ore:

[0003] 1. Copper sulfide is reduced with carbon to produce matte containing copper, iron, and other sulfides. Oxygen is then used to oxidize the sulfur in the matte to produce SO2, FeO, and blister copper. The SO2 is used to make acid, and the FeO enters the slag. The blister copper is then fire-refined and cast into electrode plates, which are then electrolytically refined to produce electrolytic copper.

[0004] 2. Directly use oxygen to oxidize the copper concentrate to obtain SO2, FeO and crude copper. SO2 is used to make acid, FeO enters the slag, and the crude copper is refined by fire and cast into electrode plates, and then electrolytically refined to obtain electrolytic copper. Summary of the Invention

[0005] The object of the present invention is to provide a method for copper smelting by reducing copper sulfide ore with hydrogen. The method for copper smelting by reducing copper sulfide ore with hydrogen comprises the following steps:

[0006] (1) Mixing copper sulfide concentrate powder with a binder and water to form pellets;

[0007] (2) Dry the prepared balls at 400℃~600℃;

[0008] (3) Add the dried balls into an electric arc furnace and heat them to 1500℃~1600℃ to melt and form a molten pool.

[0009] (4) Hydrogen is introduced into the molten pool. Copper sulfide and iron sulfide react with hydrogen to produce molten metal and slag. The chemical reaction is:

[0010] CuS+H2=Cu+H2S

[0011] CuS2+2H2=Cu+2H2S

[0012] FeS+H2=Fe+H2S

[0013] FeS2+2H2=Fe+2H2S

[0014] (5) The flue gas is introduced into the combustion chamber, and oxygen is introduced into the combustion chamber at the same time, and a chemical reaction occurs.

[0015] 2H2S+3O2=2H2O+2SO2

[0016] 2H2+O2=2H2O

[0017] (6) The heat of the flue gas is used to generate electricity. The flue gas is purified and passed to the absorption tower. Dilute sulfuric acid is sprayed from the top of the absorption tower to produce a chemical reaction.

[0018] H2O+SO2=H2SO3

[0019] Produces sulfurous acid, which is oxidized to sulfuric acid. The chemical reaction is

[0020] 2H2SO3+O2=2H2SO4

[0021] (7) When the amount of molten metal in the electric furnace reaches a certain level, stop adding material. After the reaction of the material in the furnace is complete, stop supplying hydrogen and blow oxygen into the molten metal. The chemical reaction between the iron in the molten metal and the oxygen is:

[0022] Fe+O2=FeO

[0023] The heat from the flue gases is used to generate electricity.

[0024] (8) When the iron content in the molten metal is lower than 0.5%, stop blowing oxygen and turn off the power. Discharge the slag first and then the copper.

[0025] The molten metal is cast into electrode plates and then electrolytically refined to produce electrode copper.

[0026] (9) Pour the slag into another electric arc furnace and heat it to 1600℃. Pass hydrogen into the molten pool to reduce the FeO in the slag to metallic iron, causing a chemical reaction.

[0027] FeO+H2=Fe+H2O

[0028] After the reaction is completed, slag is tapped first and then iron. The main component of the slag is SiO2, which is used to smelt industrial silicon, and the molten iron is used for steelmaking.

[0029] Flue gas is introduced into the combustion chamber, and O2 is introduced at the same time. The H2 in the flue gas reacts chemically with O2.

[0030] 2H2+O2=2H2O

[0031] The heat generated by hydrogen combustion and the heat of flue gas are used to generate electricity. The flue gas is purified and dust-removed before being discharged.

[0032] The binder in step (1) of the present invention is bentonite. The addition amount is 2% to 3% of the amount of copper sulfide concentrate; and the water content is 10% of the total amount of copper sulfide concentrate and the binder.

[0033] The size of the pellets produced in step (1) of the present invention is 20 mm to 30 mm.

[0034] The drying temperature of the pellets in step (2) of the present invention is 500°C to 600°C.

[0035] In step (3) of the present invention, the dried pellets are added to an electric arc furnace and heated to 1500°C to 1600°C to melt and form a molten pool. The electric arc furnace is an AC electric arc furnace or a DC electric arc furnace.

[0036] In step (4) of the present invention, hydrogen is introduced into the molten pool to cause a chemical reaction.

[0037] CuS+H2=Cu+H2S

[0038] CuS2+2H2=Cu+2H2S

[0039] FeS+H2=Fe+H2S

[0040] FeS2+2H2=Fe+2H2S

[0041] During the reaction, electricity is applied, pellets are added continuously, and hydrogen is passed through.

[0042] The chemical reactions that occur in the combustion chamber are

[0043] 2H2S+3O2=2H2O+2SO2

[0044] 2H2+O2=2H2O

[0045] In step (7) of the present invention, when the amount of molten metal in the electric furnace reaches a certain level, the feeding is stopped. After the reaction of the materials in the furnace is completed, the supply of hydrogen is stopped and oxygen is blown into the furnace. The chemical reaction that occurs is:

[0046] 2Fe+O2=2FeO

[0047] The generated FeO enters the slag and the heat of the flue gas is used to generate electricity.

[0048] In step (6) of the present invention, when the iron content of the copper liquid in the electric furnace is less than 0.5%, oxygen blowing is stopped and the power is turned off. The slag is first tapped, followed by the copper. The copper liquid is cast into electrode plates and sent for electrolytic refining to produce electrode copper. DETAILED DESCRIPTION

[0049] The following examples are provided to facilitate a better understanding of the present invention, but are not intended to limit the present invention. The experimental methods in the following examples, unless otherwise specified, are conventional methods. The test materials used in the following examples, unless otherwise specified, were purchased from conventional biochemical reagent stores.

[0050] In the following embodiments, unless otherwise specified, the equipment used in the steps can be existing equipment.

[0051] Example 1

[0052] Raw materials: Cu 24.01, Fe 28.60, S 29.35, SiO2 12.74, CaO 1.73, MgO 1.50, Al2O3 2.07

[0053] (1) Mixing

[0054] Copper sulfide concentrate powder with a particle size of 80μm~100μm is mixed with a binder bentonite and water, with the bentonite accounting for 2% of the total material and the water accounting for 10% of the total material.

[0055] (2) Ball making

[0056] The mixed material was formed into 20 mm pellets.

[0057] (3) Drying

[0058] The pellets are loaded into a rotary kiln and dried at 400℃~500℃ to a moisture content of less than 1%.

[0059] (4) Melting

[0060] The dried pellets are loaded into a three-phase AC electric arc furnace and heated to 1500°C to melt and form a molten pool.

[0061] (5) Reaction

[0062] When hydrogen is introduced into the molten pool, the main chemical reaction is

[0063] CuS+H2=Cu+H2S

[0064] CuS2+2H2=Cu+2H2S

[0065] FeS+H2=Fe+H2S

[0066] FeS2+2H2=Fe+2H2S

[0067] During the reaction process, electricity, hydrogen and pellets are applied.

[0068] (6) Combustion

[0069] The flue gas is passed into the combustion chamber and oxygen is supplied to the combustion chamber at the same time, and a chemical reaction occurs.

[0070] 2H2S+3O2=2H2O+2SO2

[0071] 2H2+O2=2H2O

[0072] (7) Absorbing SO2

[0073] After the flue gas of the electric furnace is dust-removed, the heat is used to generate electricity. Then the flue gas is passed into the absorption tower, and dilute sulfuric acid absorbs SO2 to obtain sulfurous acid. The sulfurous acid is oxidized by oxygen to sulfuric acid. The chemical reaction is:

[0074] SO2+H2O=H2SO3

[0075] 2H2SO3+O2=2H2SO4

[0076] (8) Iron removal

[0077] When the amount of liquid metal in the furnace reaches a certain level, stop adding material, the pellets in the furnace react completely, and stop blowing hydrogen. Continue to power on and blow oxygen into the liquid metal. The chemical reaction is:

[0078] Fe+O2=FeO

[0079] The heat from the flue gases is used to generate electricity.

[0080] (9) Cast electrode plate

[0081] When the iron content in the molten metal falls below 0.5%, oxygen blowing is stopped and the power is turned off. The slag is tapped first, followed by the copper. The molten copper is cast into electrode plates and sent for electrolytic refining to produce electrode copper.

[0082] (10) Pour the slag into another electric arc furnace, heat it, and keep the temperature at 1550℃. Blow hydrogen into the molten pool to cause a chemical reaction.

[0083] FeO+H2=Fe+H2O

[0084] After the reaction is completed, the hydrogen blowing is stopped and the power is turned off. The slag is tapped first and then the iron. The main component of the slag is SiO2, which is used to smelt industrial silicon, and the molten iron is used for steelmaking.

[0085] Flue gas is introduced into the combustion chamber, and O2 is introduced at the same time. The H2 in the flue gas reacts chemically with O2.

[0086] 2H2+O2=2H2O

[0087] The heat of the flue gas is used to generate electricity and the flue gas is discharged after being purified and dust-removed.

[0088] Example 2

[0089] Raw materials: Cu 29.20, Fe 24.36, S 26.84, SiO2 9.86, CaO 3.03, MgO 2.01, Al2O3 4.70

[0090] (1) Mixing

[0091] Copper sulfide concentrate powder with a particle size of 80μm~100μm is mixed with a binder bentonite and water, with the bentonite accounting for 2% of the total material and the water accounting for 10% of the total material.

[0092] (2) Ball making

[0093] The mixed material was formed into 20 mm pellets.

[0094] (3) Drying

[0095] The pellets are loaded into a rotary kiln and dried at 500℃~600℃ to a moisture content of less than 1%.

[0096] (4) Melting

[0097] The dried pellets are loaded into a three-phase AC electric arc furnace and heated to 1500°C to melt and form a molten pool.

[0098] (5) Reaction

[0099] When hydrogen is introduced into the molten pool, the main chemical reaction is

[0100] CuS+H2=Cu+H2S

[0101] CuS2+2H2=Cu+2H2S

[0102] FeS+H2=Fe+H2S

[0103] FeS2+2H2=Fe+2H2S

[0104] During the reaction process, electricity, hydrogen and pellets are applied.

[0105] (6) Combustion

[0106] The flue gas is passed into the combustion chamber and oxygen is supplied to the combustion chamber at the same time. The chemical reaction that occurs is:

[0107] 2H2S+3O2=2H2O+2SO2

[0108] 2H2+O2=2H2O

[0109] (7) Absorbing SO2

[0110] The flue gas heat is used for power generation. After dust removal and purification, the flue gas is passed into the absorption tower, where dilute sulfuric acid absorbs SO2 to produce sulfurous acid. The sulfurous acid is oxidized by oxygen to sulfuric acid. The chemical reaction is:

[0111] SO2+H2O=H2SO3

[0112] 2H2SO3+O2=2H2SO4

[0113] (8) Iron removal

[0114] When the amount of liquid metal in the furnace reaches a certain level, stop adding material. When the pellets in the furnace have finished reacting, stop blowing hydrogen. Continue to power on and blow oxygen into the liquid metal. The chemical reaction is:

[0115] Fe+O2=FeO

[0116] The heat from the flue gases is used to generate electricity.

[0117] (9) Cast electrode plate

[0118] When the iron content in the molten metal falls below 0.5%, oxygen blowing is stopped and the power is turned off. The molten metal is primarily copper. The slag is tapped first, followed by the copper. The copper is poured out and cast into electrode plates. These are then sent for electrolytic refining to produce electrode copper.

[0119] (10) Ironmaking

[0120] Pour the slag into another electric arc furnace and keep the temperature at 1550℃. Blow hydrogen into the furnace to cause a chemical reaction.

[0121] FeO+H2=Fe+H2O

[0122] After the reaction is completed, the hydrogen blowing is stopped and the power is turned off. The slag is tapped first and then the iron. The main component of the slag is SiO2, which is used to smelt industrial silicon, and the molten iron is used for steelmaking.

[0123] Flue gas is introduced into the combustion chamber, and O2 is introduced at the same time. The H2 in the flue gas reacts chemically with O2.

[0124] 2H2+O2=2H2O

[0125] The heat of the flue gas is used to generate electricity and the flue gas is discharged after being purified and dust-removed.

Claims

1. A method for smelting copper by reducing copper sulfide ore with hydrogen, characterized in that: The following steps are involved: (1) Mixing copper sulfide concentrate powder with a binder and water to form pellets; (2) Dry the prepared balls at 500℃~600℃; (3) Add the dried balls into an electric arc furnace and heat them to 1500℃~1600℃ to melt and form a molten pool; (4) Hydrogen is introduced into the molten pool to produce copper liquid and slag. The chemical reaction is: CuS+H2=Cu+H2S CuS2+2H2=Cu+2H2S FeS+H2=Fe+H2S FeS2+2H2=Fe+2H2S (5) The furnace gas is introduced into the combustion chamber, and oxygen is introduced into the combustion chamber at the same time to cause a chemical reaction. 2H2S+3O2=2H2O+2SO2 2H2+O2=2H2O (6) After the flue gas heat in the combustion chamber is used to generate electricity, the flue gas is purified and then passed to the absorption tower. Dilute sulfuric acid is sprayed from the top of the absorption tower to cause a chemical reaction. H2O+SO2=H2SO3 Produces sulfurous acid, which is oxidized to sulfuric acid. The chemical reaction is 2H2SO3+O2=2H2SO4 (7) After the charge in the furnace has reacted, stop supplying hydrogen to the furnace and pass oxygen into the molten pool to oxidize the iron in the molten metal into FeO, which enters the slag. The heat of the flue gas is used to generate electricity. (8) When the iron content in the molten metal is lower than 0.5%, stop blowing oxygen, turn off the power, first tap the slag, then tap the copper, cast the copper into electrode plates, and send them to electrolytic refining; (9) Pour the slag into another electric arc furnace and heat it to 1600℃. Add hydrogen to reduce the FeO in the slag to metallic iron, causing a chemical reaction. FeO+H2=Fe+H2O Flue gas heat is used to generate electricity; After the reaction is completed, slag is discharged first, and then iron. The main component of the slag is SiO2, which can be used to smelt industrial silicon, and the molten iron is used to make steel.

2. The method for copper smelting by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: The binder in step (1) is bentonite, the amount added is 2% to 3% of the mass of the copper sulfide concentrate, the amount of water added is 10% of the material, and the resulting pellet size is 20 mm to 30 mm.

3. The method for smelting copper by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: The pellets prepared in step (2) are dried at 500°C to 600°C and have a moisture content of less than 1%.

4. The method for smelting copper by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: Step (3) Add the dried pellets to a three-phase AC or DC arc furnace and heat them to 1500℃~1600℃ to melt them to form a molten pool. Then, introduce hydrogen into the molten pool. The chemical reaction that occurs is: CuS+H2=Cu+H2S CuS2+2H2=Cu+2H2S FeS+H2=Fe+H2S FeS2+2H2=Fe+2H2S.

5. The method for smelting copper by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: In step (5), the flue gas is introduced into the combustion chamber, and O2 is introduced into the combustion chamber. The chemical reaction that occurs is: 2H2S+3O2=2H2O+2SO2 2H2+O2=2H2O.

6. The method for smelting copper by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: In step (6), the flue gas heat is used to generate electricity, and then the flue gas is purified and passed to the absorption tower, and dilute sulfuric acid is sprayed from the top of the absorption tower to cause a chemical reaction. <h2 style=";text-align:left;direction:ltr">H2O+SO2=H2SO<h2 style=";text-align:left;direction:ltr"> 3。 7. The method for smelting copper by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: In step (7), pellets are continuously added to the electric furnace and hydrogen is passed through during the reaction process. After the pellets have reacted and the metal liquid in the furnace reaches a certain amount, the hydrogen is stopped and oxygen is passed through the metal liquid. The reaction that occurs is: 2Fe+O2=2FeO FeO enters the slag.

8. The method for smelting copper by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: In step (8), when the iron content of the molten metal in the electric furnace is less than 0.5%, oxygen blowing is stopped and the power is turned off. The slag is discharged first, followed by the copper. The copper liquid is cast into anode plates and sent for electrolytic refining.

9. The method for smelting copper by reducing copper sulfide ore with hydrogen according to claim 1, characterized in that: In step (9), the slag is poured into another electric arc furnace, and hydrogen is passed through to reduce FeO to metallic iron. The slag is first discharged and then the iron is discharged. The iron is sent to steelmaking. The main component of the slag is SiO2, which is used to smelt industrial silicon.

10. The flue gas produced in step (9) is introduced into the combustion chamber, and oxygen is introduced into the combustion chamber at the same time. The heat generated by the combustion of excess hydrogen and the heat of the flue gas are used to generate electricity.