A fluidized bed roasting method and apparatus for copper-zinc concentrate

Abstract

A fluidized bed roasting method for copper-zinc concentrate includes the following steps: 1) grinding the copper-zinc concentrate to obtain copper-zinc concentrate powder; 2) introducing fluidizing gas into a fluidized bed device, and by controlling the introduction method and amount of the fluidizing gas, forming a high-flow-rate roasting zone, a low-flow-rate roasting zone, and optionally including or excluding a medium-flow-rate roasting zone located between the high-flow-rate and low-flow-rate roasting zones from bottom to top in the fluidized bed device; 3) adding the copper-zinc concentrate powder into the fluidized bed device for roasting treatment, and after the reaction is completed, discharging all the roasted ore from the fluidized bed device. This invention enables low-copper-content, medium-copper-content, and high-copper-content copper-zinc concentrates to react in separate zones within a fluidized bed device, solving the problem of furnace deadlock caused by copper oxide accumulation, achieving precise and efficient roasting of copper-zinc concentrates, and significantly improving resource utilization.

Description

Technical Field

[0001] This invention relates to a fluidized bed roasting method and apparatus, specifically to a fluidized bed roasting method and apparatus for copper-zinc concentrate, belonging to the field of fluidized bed roasting technology. Background Technology

[0002] Since the 1980s, over 85% of the world's zinc production has been produced through hydrometallurgical processes. Hydrometallurgical zinc refining typically involves pre-oxidative roasting of zinc sulfide concentrate to produce zinc oxide roast, which can be dissolved in dilute sulfuric acid. Fluidized bed roasting of zinc concentrate is the first and most critical step in hydrometallurgical zinc refining; its ability to produce qualified roast directly impacts subsequent hydrometallurgical processes. With the continuous depletion of domestic zinc resources and rapid market changes, smelters, in pursuit of maximum profits, are selecting increasingly complex zinc concentrates for their furnaces, typically characterized by high lead, high copper, high silicon, and high iron content. These high-impurity zinc concentrates, during roasting, not only undergo oxidation reactions to varying degrees, similar to zinc sulfide, but their intermediate products can further form various salts, such as zinc ferrite, zinc silicate, and lead silicate. For example, the zinc ferrite formed is difficult to dissolve in dilute sulfuric acid, which reduces the direct recovery rate of zinc; zinc silicate produces colloids during leaching, making solid-liquid separation difficult; and low-melting-point lead silicate will seriously affect the boiling roasting process.

[0003] In zinc concentrate, copper exists primarily as sulfides, mainly chalcocite (Cu₂S), chalcopyrite (CuFeS₂), and covellite (CuS). During fluidized bed roasting, oxidation is exothermic, ultimately resulting in the majority of copper as CuO and Cu₂O. Small amounts of CuSO₄, copper ferrite, and copper silicate are also present in the products. Copper sulfides undergo the following reactions at relatively low temperatures of around 500℃:

[0004] 2Cu₂S + 5O₂ = 2CuO + 2CuSO₄

[0005] 2CuFeS2=Cu2S+2FeS+0.5S2

[0006] CuS + 2O₂ = CuSO₄

[0007] Copper sulfate produced at low temperatures is thermodynamically unstable and will rapidly decompose according to the following formula when the calcination temperature exceeds 700℃:

[0008] 5CuSO4 + 3CuS = 4Cu2O + 8SO2

[0009] 2CuSO4=CuO·CuSO4+SO2+0.5O2

[0010] CuO.CuSO4=2CuO+SO2+0.5O2

[0011] The main copper sulfides react at this temperature according to the following chemical equation:

[0012] 2Cu₂S + 3O₂ = 2Cu₂O + 2SO₂

[0013] 2Cu₂S + 3O₂ = 2CuO + 2SO₂

[0014] 4CuS + 5O2 = 2Cu2O + 4SO2

[0015] 12CuFeS2+35O2=6Cu2O+4Fe3O4+24SO2

[0016] Analysis of the above chemical reaction equations and Cu-SO isothermal chemical curves revealed that, under actual boiling roasting temperatures and oxygen and sulfur potential atmospheres, copper impurities in zinc concentrate mainly exist in the forms of CuO and Cu2O. A small portion may exist in the form of copper ferrite.

[0017] Fluidized bed roasting of zinc concentrate is a crucial step in zinc production, significantly impacting subsequent processes. The smooth operation of the fluidized bed roasting furnace directly affects the overall system's performance. Due to the similar mineralization properties of copper and zinc, zinc concentrate often contains a certain amount of copper. High-copper zinc concentrate is prevalent in the market, and the copper content in the feed material is required to be less than 0.7%. However, the copper content in zinc concentrate frequently exceeds this standard, sometimes reaching 6-8 times the normal level. Copper negatively affects the fluidized bed roasting of zinc concentrate; the Cu₂O and CuO produced during roasting have high densities, typically around 6 g / cm³. 3 The density of ZnO is 5.606 g / cm³. 3 The bulk density of zinc calcined sand is generally 1.7-2.0 g / cm³. 3 Therefore, the copper oxides generated during roasting are relatively heavy and easily deposit at the bottom of the fluidized bed, and are also prone to forming matte, which lowers the melting point of the charge. This leads to accumulation at the bottom of the furnace, causing a scorching phenomenon, which reduces the fluidity of the charge, makes discharge difficult, and easily causes furnace failure. At the same time, the copper roasting process generates a large amount of heat, making it difficult to control the roasting temperature. Local high temperatures in the system can easily cause agglomeration. Once large-scale sintering occurs in the fluidized bed, the furnace condition will deteriorate severely, ultimately leading to furnace failure and shutdown. Summary of the Invention

[0018] To address the problems of copper oxides easily causing burnt bottoms and furnace failure in existing technologies, this solution proposes a fluidized bed roasting method and apparatus for copper-zinc concentrates. After zinc concentrates with high, medium, and low copper contents enter the fluidized bed apparatus, the flow rate of the fluidizing gas is controlled to ensure that the gas flow velocity is low at the top and high at the bottom. This allows the zinc concentrates with different copper contents to react fully in different zones within the fluidized bed apparatus, solving the problem of copper oxide accumulation and achieving precise separation and efficient roasting of copper and zinc oxides.

[0019] According to a first embodiment of the present invention, a fluidized bed roasting method for copper-zinc concentrate is provided.

[0020] A fluidized bed roasting method for copper-zinc concentrate, the method comprising the following steps:

[0021] 1) Grind the copper-zinc concentrate to obtain copper-zinc concentrate powder;

[0022] 2) Fluidizing gas is introduced into the fluidization device. By controlling the introduction method and the amount of fluidizing gas, a high flow rate roasting zone, a low flow rate roasting zone, and a medium flow rate roasting zone, optionally including or excluding, located between the high flow rate roasting zone and the low flow rate roasting zone, are formed from bottom to top in the fluidization device.

[0023] 3) Add copper-zinc concentrate powder to the fluidized bed roasting device for roasting. During the fluidized bed roasting process, control the flow rate of the fluidizing gas in the high-flow-rate roasting zone, medium-flow-rate roasting zone, and low-flow-rate roasting zone so that the copper-zinc concentrate with high copper content enters the high-flow-rate roasting zone for reaction, the copper-zinc concentrate with medium copper content enters the medium-flow-rate roasting zone for reaction, and the copper-zinc concentrate with low copper content enters the low-flow-rate roasting zone for reaction. After the reaction is completed, discharge all the roasted ore from the fluidized bed roasting device.

[0024] Preferably, the flow rate of the fluidizing gas in the high-flow-rate roasting zone, medium-flow-rate roasting zone, and low-flow-rate roasting zone is controlled by calculating the required air velocity and air volume to ensure that all copper-zinc concentrate in each zone enters the fluidized roasting state based on parameters such as the cross-sectional area of ​​the fluidization device and the mass of the copper-zinc concentrate. The required air volume is then introduced into the fluidization device based on the calculated results.

[0025] Preferably, the upper and lower cross-sectional areas of the fluidization device are equal; the flow rates of the fluidizing gas in the high-flow-rate roasting zone, medium-flow-rate roasting zone, and low-flow-rate roasting zone are controlled as follows: gas outlets are opened on the sidewalls at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone, and on the sidewalls at the junction of the medium-flow-rate roasting zone and the low-flow-rate roasting zone; fluidizing gas is first introduced into the lower part of the high-flow-rate roasting zone, and then excess fluidizing gas in the high-flow-rate roasting zone and the medium-flow-rate roasting zone is led out through the gas outlets, so that the wind speeds in the low-flow-rate roasting zone, the medium-flow-rate roasting zone, and the high-flow-rate roasting zone meet the fluidization wind speed requirements of low-copper-content copper-zinc concentrate, medium-copper-content copper-zinc concentrate, and high-copper-content copper-zinc concentrate, respectively.

[0026] Preferably, the flow rate of the fluidizing gas introduced into the lower part of the high-flow-rate calcination zone is:

[0027]

[0028] In the formula, G1 is the air volume introduced into the high-flow-rate roasting zone, in m 3 / s; m1 is the mass of copper-zinc concentrate with high copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C1 is the resistance coefficient of copper-zinc concentrate with high copper content, ranging from 0.2 to 0.5; S is the cross-sectional area of ​​the fluidized bed roasting device, in m³. 2 S1 represents the projected area of ​​a high-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 ;

[0029] Simultaneously, the gas flow rate drawn from the gas outlet at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone is controlled as follows:

[0030]

[0031] In the formula, G2 is the gas flow rate drawn from the gas outlet at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone, in m. 3 / s; m2 is the mass of copper-zinc concentrate with medium copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C2 is the resistance coefficient of copper-zinc concentrate with medium copper content, ranging from 0.2 to 0.5; S is the cross-sectional area of ​​the fluidized bed roasting device, in m³. 2 S2 represents the projected area of ​​a medium-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 ;

[0032] Similarly, the gas flow rate drawn from the gas outlet at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone is:

[0033]

[0034] In the formula, G3 is the gas flow rate drawn from the gas outlet at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone, in m. 3 / s; m3 is the mass of copper-zinc concentrate with low copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C3 is the resistance coefficient of copper-zinc concentrate with low copper content, ranging from 0.2 to 0.5; S is the cross-sectional area of ​​the fluidized bed roasting device, in m³. 2 S3 represents the projected area of ​​a low-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 ;

[0035] Controlling G1, G2, and G3 to satisfy (Equation 1), (Equation 2), and (Equation 3) respectively ensures that the copper-zinc concentrate with low copper content, the copper-zinc concentrate with medium copper content, and the copper-zinc concentrate with high copper content are all in a stable fluidized state in the low-flow-rate roasting zone, the medium-flow-rate roasting zone, and the high-flow-rate roasting zone, respectively.

[0036] Preferably, the cross-sectional area inside the fluidization device increases from bottom to top; the control of the fluidizing gas flow rate in the high-flow-rate roasting zone, medium-flow-rate roasting zone, and low-flow-rate roasting zone is as follows: based on the differences between the cross-sectional areas of the high-flow-rate roasting zone, medium-flow-rate roasting zone, and low-flow-rate roasting zone, as well as parameters such as the mass and projected area perpendicular to the wind direction of the low-copper-content copper-zinc concentrate, medium-copper-content copper-zinc concentrate, and high-copper-content copper-zinc concentrate, the wind speed in the high-flow-rate roasting zone, medium-flow-rate roasting zone, and low-flow-rate roasting zone is calculated, and the air volume introduced into the bottom of the high-flow-rate roasting zone is controlled according to the calculated wind speed;

[0037] Preferably, ventilation holes are provided on the sidewalls at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone, and at the junction of the medium-flow-rate roasting zone and the low-flow-rate roasting zone in the fluidization device, so as to control the gas flow rate introduced into the bottom of the high-flow-rate roasting zone and the gas flow rate introduced or discharged through the ventilation holes, so that the copper-zinc concentrate is in a stable fluidized state.

[0038] Preferably, the flow rate of the fluidizing gas introduced into the lower part of the high-flow-rate calcination zone is:

[0039]

[0040] In the formula, G4 is the air volume introduced into the lower part of the high-flow-rate roasting zone, in m. 3 / s; m1 is the mass of copper-zinc concentrate with high copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³3 C1 is the resistance coefficient of copper-zinc concentrate with high copper content, ranging from 0.2 to 0.5; S4 is the minimum cross-sectional area in the high-flow-rate roasting zone, in meters. 2 S1 represents the projected area of ​​a high-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 .

[0041] It should be noted that, since the fluidization device has a cross-sectional area that increases from bottom to top and is narrower at the bottom than at the top, even without the ventilation holes on the sidewalls at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone, as well as the ventilation holes on the sidewalls at the junction of the medium-flow-rate roasting zone and the low-flow-rate roasting zone, it is only necessary to satisfy Equation 4 to achieve the conditions for the reaction of copper-zinc concentrates of all particle sizes in the fluidization device (i.e., the copper-zinc concentrate with high copper content reacts at the bottom of the device, the copper-zinc concentrate with medium copper content reacts at a slightly higher height than the copper-zinc concentrate with high copper content, and the copper-zinc concentrate with low copper content reacts at a slightly higher height than the copper-zinc concentrate with medium copper content). At the same time, when the ore is discharged after the reaction is completed, G4 can be gradually increased so that the copper-zinc concentrate with low copper content is discharged first and the copper-zinc concentrate with high copper content is discharged last, thus achieving the effect of separating the ore according to the different copper contents.

[0042] Preferably, the gas flow rate at the vent at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone is controlled as follows:

[0043]

[0044] In the formula, G5 is the gas flow rate at the vent at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone, in m. 3 / s; m2 is the mass of copper-zinc concentrate with medium copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C2 is the resistance coefficient of copper-zinc concentrate with medium copper content, ranging from 0.2 to 0.5; S5 is the minimum cross-sectional area in the medium-flow-rate roasting zone, in meters. 2 S2 represents the projected area of ​​a medium-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 When G5 is less than 0, the absolute value of G5 is the gas flow rate that is exhausted outward through the vent at the bottom of the medium flow rate roasting zone. When G5 is greater than 0, the value of G5 is the gas flow rate that is introduced into the medium flow rate roasting zone through the vent at the bottom of the medium flow rate roasting zone.

[0045] The gas flow rate at the vent at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone is controlled as follows:

[0046]

[0047] In the formula, G6 is the gas flow rate at the vent at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone, in m. 3 / s; m3 is the mass of copper-zinc concentrate with low copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C3 is the resistance coefficient of copper-zinc concentrate with low copper content, ranging from 0.2 to 0.5; S6 is the minimum cross-sectional area in the low-flow-rate roasting zone, in meters. 2 S3 represents the projected area of ​​a medium-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 Wherein, when G6 is less than 0, the absolute value of G6 is the gas flow rate that is exhausted outward through the vent at the bottom of the low flow rate roasting zone; when G6 is greater than 0, the value of G6 is the gas flow rate that is introduced into the low flow rate roasting zone through the vent at the bottom of the low flow rate roasting zone.

[0048] Preferably, the particle size of the copper-zinc concentrate powder is less than 3 mm, and more preferably less than 1 mm;

[0049] Preferably, the step of adding the copper-zinc concentrate powder to the fluidization device is: adding the copper-zinc concentrate powder from the feed inlet at the top of the fluidization device.

[0050] According to a second embodiment of the present invention, a fluidized bed roasting apparatus for copper-zinc concentrate is provided.

[0051] A fluidized bed roasting apparatus for copper-zinc concentrate includes a furnace body and a gas supply pipeline. The furnace body is vertically arranged and has a feed inlet on its top and a fluidizing gas inlet at its bottom. From bottom to top, the internal area of ​​the furnace body is divided into a high-flow-rate roasting zone, a low-flow-rate roasting zone, and optionally, a medium-flow-rate roasting zone located between the high-flow-rate and low-flow-rate roasting zones. The gas supply pipeline includes a first gas supply pipeline connected to the fluidizing gas inlet.

[0052] Preferably, the gas supply pipeline further includes a second gas supply pipeline and a third gas supply pipeline. Ventilation holes are provided on the sidewalls at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone, and on the sidewalls at the boundary between the low-flow-rate roasting zone and the medium-flow-rate roasting zone. The second gas supply pipeline is connected to the vent hole at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone, and the third gas supply pipeline is connected to the vent hole at the boundary between the low-flow-rate roasting zone and the medium-flow-rate roasting zone.

[0053] Preferably, both the second and third gas pipelines are equipped with bidirectional fans.

[0054] Preferably, the feed inlet is located at the top of the furnace body.

[0055] Preferably, a disturbance mechanism is also provided at the bottom of the furnace body.

[0056] Preferably, the cross-sectional area inside the furnace body is equal from bottom to top.

[0057] Preferably, the cross-sectional area inside the furnace body is larger at the top and smaller at the bottom. The cross-sectional area of ​​the high-flow-rate roasting zone is equal from top to bottom, the cross-sectional area of ​​the low-flow-rate roasting zone is equal from top to bottom, and the cross-sectional area of ​​the high-flow-rate roasting zone is smaller than that of the low-flow-rate roasting zone. The cross-sectional area at the lower end of the medium-flow-rate roasting zone is equal to that of the high-flow-rate roasting zone, the cross-sectional area at the upper end of the medium-flow-rate roasting zone is equal to that of the low-flow-rate roasting zone, and the cross-sectional area of ​​the medium-flow-rate roasting zone gradually increases from bottom to top.

[0058] Preferably, the cross-sectional area inside the furnace body is larger at the top and smaller at the bottom. The cross-sectional area of ​​the high-flow-rate roasting zone is equal from top to bottom, and the cross-sectional area of ​​the low-flow-rate roasting zone is also equal from top to bottom, with the cross-sectional area of ​​the high-flow-rate roasting zone being smaller than that of the low-flow-rate roasting zone. The bottom of the high-flow-rate roasting zone is connected to the top of the low-flow-rate roasting zone. Ventilation holes are provided on the outer ring adjacent to the bottom of the high-flow-rate roasting zone and the top of the low-flow-rate roasting zone.

[0059] Preferably, the cross-sectional area inside the furnace body is larger at the top and smaller at the bottom, and the cross-sectional area of ​​the high-speed fluidized roasting zone, the medium-flow-rate roasting zone, and the low-flow-rate roasting zone gradually increases.

[0060] In this invention, the detailed calculation process for G1, G2, G3, G4, G5, and G6 is as follows:

[0061] When the fluidization device has a structure with equal upper and lower cross-sectional areas:

[0062] High-copper-content copper-zinc concentrate is subjected to fluidized bed roasting in a high-flow-rate roasting zone. The required air velocity for the high-flow-rate roasting zone is:

[0063]

[0064] In the formula, V a m1 is the required air velocity in the high-flow-rate roasting zone, in m / s; g is the mass of the copper-zinc concentrate with high copper content, in kg; and g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C1 is the drag coefficient of the high-copper-content copper-zinc concentrate, with a value of 0.2-0.5; S1 is the projected area of ​​the high-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 ;

[0065] Based on the relationship between air volume and air velocity:

[0066]

[0067] In the formula, S is the cross-sectional area of ​​the fluidized bed roasting device, m 2 ;

[0068] Based on equations 7 and 8, equation 1 can be derived.

[0069] Similarly, copper-zinc concentrate with medium copper content undergoes fluidized bed roasting in a medium flow rate roasting zone. The required air velocity for the medium flow rate roasting zone is:

[0070]

[0071] In the formula, V b 1 is the required air velocity in the medium-flow-rate roasting zone, m / s; m2 is the mass of copper-zinc concentrate with medium copper content, kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C2 is the drag coefficient of copper-zinc concentrate with medium copper content, ranging from 0.2 to 0.5; S2 is the projected area of ​​copper-zinc concentrate with medium copper content perpendicular to the wind direction, in meters. 2 ;

[0072] Based on the relationship between air volume and air velocity:

[0073]

[0074] In the formula, S is the cross-sectional area of ​​the fluidized bed roasting device, m 2 ;

[0075] Based on Equations 9 and 10, Equation 2 can be derived.

[0076] Low-copper-content copper-zinc concentrate is subjected to fluidized bed roasting in a low-flow-rate roasting zone. The required air velocity for the low-flow-rate roasting zone is:

[0077]

[0078] In the formula, V c ρ is the required air velocity in the low-flow-rate roasting zone, m / s; m3 is the mass of copper-zinc concentrate with low copper content, kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C3 is the drag coefficient of the low-copper-content copper-zinc concentrate, with a value of 0.2-0.5; S3 is the projected area of ​​the low-copper-content copper-zinc concentrate perpendicular to the wind direction, in m². 2 ;

[0079] Based on the relationship between air volume and air velocity:

[0080]

[0081] In the formula, S is the cross-sectional area of ​​the fluidized bed roasting device, m 2 ;

[0082] Based on (Equation 11) and (Equation 12), (Equation 3) can be derived.

[0083] When the fluidization device has a structure where the cross-sectional area increases from bottom to top:

[0084] The air velocity in the high-flow-rate roasting zone is:

[0085]

[0086] The required air velocity in the high-flow-rate roasting zone is:

[0087]

[0088] G4 represents the air volume (m) introduced into the high-flow-rate roasting zone. 3 / s; m1 is the mass of copper-zinc concentrate with high copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C1 is the resistance coefficient of copper-zinc concentrate with high copper content, ranging from 0.2 to 0.5; S4 is the minimum cross-sectional area in the high-flow-rate roasting zone, in meters. 2 S1 represents the projected area of ​​a high-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 .

[0089] Based on equations 13 and 14, equation 4 can be derived.

[0090] Similarly, the wind speed in the medium-flow-rate roasting zone is:

[0091]

[0092] The required air velocity in the medium flow rate roasting zone is:

[0093]

[0094] In the formula, G5 is the gas flow rate at the vent at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone, in m. 3 / s; m2 is the mass of copper-zinc concentrate with medium copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C2 is the resistance coefficient of copper-zinc concentrate with medium copper content, ranging from 0.2 to 0.5; S5 is the minimum cross-sectional area in the medium-flow-rate roasting zone, in meters. 2 S2 represents the projected area of ​​a medium-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 .

[0095] Based on Equations 15 and 16, Equation 5 can be derived.

[0096] In addition, the air velocity in the low-flow-rate roasting zone is:

[0097]

[0098] The required air velocity in the low-flow-rate roasting zone is:

[0099]

[0100] In the formula, G6 is the gas flow rate at the vent at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone, in m. 3 / s; m3 is the mass of copper-zinc concentrate with low copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ρ is the air density, kg / m³ 3 C3 is the resistance coefficient of copper-zinc concentrate with low copper content, ranging from 0.2 to 0.5; S6 is the minimum cross-sectional area in the low-flow-rate roasting zone, in meters. 2 S3 represents the projected area of ​​a medium-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 .

[0101] Based on (Equation 17) and (Equation 18), (Equation 6) can be derived.

[0102] In this invention, the internal region of the fluidization device is divided into a high-flow-rate roasting zone and a low-flow-rate roasting zone, and optionally includes or excludes a medium-flow-rate roasting zone located between the high-flow-rate and low-flow-rate roasting zones. After the copper-zinc concentrate powder enters the fluidization device, the gas flow rate can be controlled to cause the low-copper-content copper-zinc concentrate to undergo a fluidization reaction in the low-flow-rate roasting zone, the high-copper-content copper-zinc concentrate to undergo a fluidization reaction in the high-flow-rate roasting zone, and the medium-copper-content copper-zinc concentrate to undergo a fluidization reaction in the medium-flow-rate roasting zone (when the medium-flow-rate roasting zone is set). This solves the problem of furnace deadening caused by copper oxide accumulation, achieves precise and efficient roasting of copper-zinc concentrate powder, and significantly improves resource utilization.

[0103] In this invention, the fluidization device can be a structure with an increasing cross-sectional area from bottom to top or a structure with an equal cross-sectional area from bottom to top. Simultaneously, based on the specific properties of low-copper-content copper-zinc concentrate, medium-copper-content copper-zinc concentrate, and high-copper-content copper-zinc concentrate (as well as medium-copper-content copper-zinc concentrate), the air velocities in the low-flow-rate roasting zone, medium-flow-rate roasting zone, and high-flow-rate roasting zone of the fluidization device are calculated. The airflow is then controlled based on the calculated air velocities to improve the stability and efficiency of the fluidization reaction process. Since the low-flow-rate roasting zone, medium-flow-rate roasting zone, and high-flow-rate roasting zone of the fluidization device are interconnected, the fluidizing gas in the high-flow-rate roasting zone will eventually pass through the low-flow-rate roasting zone and the medium-flow-rate roasting zone before being discharged from the fluidization device. Therefore, when calculating the air volume in the low-flow-rate roasting zone, the gas flow rate into the high-flow-rate roasting zone and the gas flow rate into the low-flow-rate roasting zone and the medium-flow-rate roasting zone should be calculated simultaneously. Based on the calculation results, the gas flow rate into the high-flow-rate roasting zone, the medium-flow-rate roasting zone, and the low-flow-rate roasting zone should be controlled (when it is necessary to discharge gas from the vent, the gas flow rate should be negative), thereby achieving fluidized roasting and precise control of copper-zinc concentrates with different copper contents.

[0104] In this invention, it should be noted that when the fluidization device has a structure with an increasing cross-sectional area from bottom to top, the wind speed only needs to meet the requirement that copper-zinc concentrate with low copper content is suspended in the low-flow-rate roasting zone and copper-zinc concentrate with high copper content is suspended in the high-flow-rate roasting zone. Therefore, the wind speed and air volume can be calculated using the minimum cross-sectional area in the low-flow-rate roasting zone and the high-flow-rate roasting zone, and the wind speed can be a range value. In practical applications, the height of copper-zinc concentrate in each zone can be adjusted by controlling the wind speed to achieve precise control. In addition, when the ore reaction is completed and discharged, it can also be discharged in batches according to the copper content of the ore from low to high.

[0105] In this invention, the fluidization device can also open vents at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone (and the junction of the medium-flow-rate roasting zone and the low-flow-rate roasting zone) to draw out excess fluidizing gas in the high-flow-rate roasting zone (and the medium-flow-rate roasting zone) or to replenish fluidizing gas in the high-flow-rate roasting zone (and the medium-flow-rate roasting zone), so as to control the airflow velocity in the medium-flow-rate roasting zone and the low-flow-rate roasting zone, adjust the fluidization height of copper-zinc concentrate with medium copper content and copper-zinc concentrate with low copper content, and achieve precise control.

[0106] In this invention, the copper-zinc concentrate is added from the top of the fluidization device. Compared to bottom feeding, the material can directly reach the appropriate position and react directly from the top, avoiding the problem of excessive air velocity in the high-flow-rate roasting zone, which could cause the low-copper-content copper-zinc concentrate to be pushed upwards out of the fluidization device or exceed the height of the reaction zone. Furthermore, since the mineral particles and fluidizing gas enter the fluidization device from different positions, it is easier to control during actual production applications.

[0107] In this invention, a disturbance mechanism can also be provided at the bottom of the furnace body to prevent copper-zinc concentrate particles from falling to the bottom of the furnace.

[0108] In this invention, a medium flow rate roasting zone may or may not be provided. When the medium flow rate roasting zone is not provided, the copper-zinc concentrate with medium copper content is fluidized and roasted in the middle area between the high flow rate roasting zone and the low flow rate roasting zone, or moves back and forth between the high flow rate roasting zone and the low flow rate roasting zone, without affecting the roasting effect of the copper-zinc concentrate with medium copper content.

[0109] In this invention, m1, m2, and m3 in equations (1) to (6) refer to the mass of a single copper-zinc concentrate particle. The values ​​of C1, C2, and C3 are determined based on parameters such as the diameter of the single copper-zinc concentrate particle in actual applications.

[0110] Compared with the prior art, the present invention has the following beneficial effects:

[0111] 1. The present invention provides a fluidized bed roasting method for copper-zinc concentrate, which enables copper-zinc concentrate with low copper content, medium copper content and high copper content to react in separate zones in a fluidized bed device, solving the problem of furnace dead caused by copper oxide accumulation, realizing precise and efficient roasting of copper-zinc concentrate, and greatly improving resource utilization.

[0112] 2. The present invention provides a fluidized bed roasting method for copper-zinc concentrate, which provides two optional structures for the fluidized bed device. Through calculation, the air volume introduced or discharged into the high flow rate roasting zone, the medium flow rate roasting zone and the low flow rate roasting zone can be controlled to achieve precise control in the roasting process. At the same time, it can also separate copper-zinc concentrates with different copper contents.

[0113] 3. The present invention provides a fluidized bed roasting device for copper-zinc concentrate, which discloses the specific structure of the fluidized bed device and realizes the zoned fluidized bed reaction of copper-zinc concentrate with low copper content, copper-zinc concentrate with medium copper content and copper-zinc concentrate with high copper content. The device has a simple structure and strong practicality. Attached Figure Description

[0114] Figure 1 This is a schematic diagram of the first structure of a fluidized bed roasting apparatus for copper-zinc concentrate provided by the present invention.

[0115] Figure 2 This is a schematic diagram of a second structure of the furnace body in a fluidized bed roasting apparatus for copper-zinc concentrate provided by the present invention.

[0116] Figure 3 This is a schematic diagram of a third structure of the furnace body in a fluidized bed roasting apparatus for copper-zinc concentrate provided by the present invention.

[0117] Figure 4 This is a schematic diagram of the fourth structure of the furnace body in a fluidized bed roasting apparatus for copper-zinc concentrate provided by the present invention.

[0118] Reference numerals: 1: Furnace body; 101: High flow rate roasting zone; 102: Medium flow rate roasting zone; 103: Low flow rate roasting zone; 2: Gas supply pipe; 201: First gas supply pipe; 202: Second gas supply pipe; 203: Third gas supply pipe; 3: Disturbance mechanism. Detailed Implementation

[0119] The technical solution of the present invention will be illustrated below with examples. The scope of protection sought by the present invention includes, but is not limited to, the following embodiments.

[0120] According to an embodiment of the present invention, a fluidized bed roasting apparatus for copper-zinc concentrate is provided.

[0121] A fluidized bed roasting apparatus for copper-zinc concentrate includes a furnace body 1 and a gas supply pipe 2. The furnace body 1 is vertically arranged and has a feed inlet on its top. A fluidizing gas inlet is located at the bottom of the furnace body 1. From bottom to top, the internal area of ​​the furnace body 1 is divided into a high-flow-rate roasting zone 101, a low-flow-rate roasting zone 103, and optionally, a medium-flow-rate roasting zone 102 located between the high-flow-rate roasting zone 101 and the low-flow-rate roasting zone 103. The gas supply pipe 2 includes a first gas supply pipe 201, which is connected to the fluidizing gas inlet.

[0122] Preferably, the gas supply pipe 2 further includes a second gas supply pipe 202 and a third gas supply pipe 203. Ventilation holes are provided on the sidewalls at the junction of the high-flow-rate roasting zone 101 and the medium-flow-rate roasting zone 102, and on the sidewalls at the junction of the low-flow-rate roasting zone 103 and the medium-flow-rate roasting zone 102. The second gas supply pipe 202 is connected to the ventilation hole at the junction of the high-flow-rate roasting zone 101 and the medium-flow-rate roasting zone 102, and the third gas supply pipe 203 is connected to the ventilation hole at the junction of the low-flow-rate roasting zone 103 and the medium-flow-rate roasting zone 102.

[0123] Preferably, both the second gas pipeline 202 and the third gas pipeline 203 are equipped with bidirectional fans.

[0124] Preferably, the feed inlet is located at the top of the furnace body 1.

[0125] Preferably, a disturbance mechanism 3 is also provided at the bottom of the furnace body 1.

[0126] Preferably, the cross-sectional area inside the furnace body 1 is equal from bottom to top.

[0127] Preferably, the cross-sectional area inside the furnace body 1 is larger at the top and smaller at the bottom. The cross-sectional area of ​​the high-flow-rate roasting zone 101 is equal from top to bottom, and the cross-sectional area of ​​the low-flow-rate roasting zone 103 is equal from top to bottom, with the cross-sectional area of ​​the high-flow-rate roasting zone 101 being smaller than that of the low-flow-rate roasting zone 103. The cross-sectional area at the lower end of the medium-flow-rate roasting zone 102 is equal to that of the high-flow-rate roasting zone 101, and the cross-sectional area at the upper end of the medium-flow-rate roasting zone 102 is equal to that of the low-flow-rate roasting zone 101, with the cross-sectional area of ​​the medium-flow-rate roasting zone 102 gradually increasing from bottom to top.

[0128] Preferably, the cross-sectional area inside the furnace body 1 is larger at the top and smaller at the bottom. The cross-sectional area of ​​the high-flow-rate roasting zone 101 is equal from top to bottom, and the cross-sectional area of ​​the low-flow-rate roasting zone 103 is equal from top to bottom, with the cross-sectional area of ​​the high-flow-rate roasting zone 101 being smaller than that of the low-flow-rate roasting zone 103. The bottom of the high-flow-rate roasting zone 101 is connected to the top of the low-flow-rate roasting zone 103, and an air inlet is provided on the outer ring of the top of the low-flow-rate roasting zone 103.

[0129] Preferably, the cross-sectional area inside the furnace body 1 is larger at the top and smaller at the bottom, and the cross-sectional areas of the high-speed fluidized roasting zone 101, the medium-flow-rate roasting zone 102, and the low-flow-rate roasting zone 103 gradually increase.

[0130] Example 1

[0131] A fluidized bed roasting apparatus for copper-zinc concentrate includes a furnace body 1 and a gas supply pipe 2. The furnace body 1 is vertically arranged and has a feed inlet on its top. A fluidizing gas inlet is located at the bottom of the furnace body 1. From bottom to top, the internal area of ​​the furnace body 1 is divided into a high-flow-rate roasting zone 101, a low-flow-rate roasting zone 103, and a medium-flow-rate roasting zone 102 located between the high-flow-rate roasting zone 101 and the low-flow-rate roasting zone 103. The gas supply pipe 2 includes a first gas supply pipe 201, which is connected to the fluidizing gas inlet.

[0132] Example 2

[0133] The embodiment 1 is repeated, except that the gas supply pipe 2 also includes a second gas supply pipe 202 and a third gas supply pipe 203. Ventilation holes are provided on the sidewalls at the junction of the high-flow-rate roasting zone 101 and the medium-flow-rate roasting zone 102, and on the sidewalls at the junction of the low-flow-rate roasting zone 103 and the medium-flow-rate roasting zone 102. The second gas supply pipe 202 is connected to the ventilation hole at the junction of the high-flow-rate roasting zone 101 and the medium-flow-rate roasting zone 102, and the third gas supply pipe 203 is connected to the ventilation hole at the junction of the low-flow-rate roasting zone 103 and the medium-flow-rate roasting zone 102.

[0134] Example 3

[0135] The second embodiment is repeated, except that both the second gas pipeline 202 and the third gas pipeline 203 are equipped with bidirectional fans.

[0136] The feed inlet is located at the top of the furnace body 1. A disturbance mechanism 3 is also provided at the bottom of the furnace body 1.

[0137] Example 4

[0138] like Figure 1 As shown, Example 3 is repeated, except that the cross-sectional area inside the furnace body 1 is equal from bottom to top.

[0139] Example 5

[0140] like Figure 2 As shown, Embodiment 3 is repeated, except that the cross-sectional area inside the furnace body 1 is larger at the top and smaller at the bottom. The cross-sectional area of ​​the high-flow-rate roasting zone 101 is equal from top to bottom, and the cross-sectional area of ​​the low-flow-rate roasting zone 103 is equal from top to bottom, with the cross-sectional area of ​​the high-flow-rate roasting zone 101 being smaller than that of the low-flow-rate roasting zone 103. The cross-sectional area at the lower end of the medium-flow-rate roasting zone 102 is equal to that of the high-flow-rate roasting zone 101, and the cross-sectional area at the upper end of the medium-flow-rate roasting zone 102 is equal to that of the low-flow-rate roasting zone 101, with the cross-sectional area of ​​the medium-flow-rate roasting zone 102 gradually increasing from bottom to top.

[0141] Example 6

[0142] like Figure 3 As shown, Embodiment 3 is repeated, except that the cross-sectional area inside the furnace body 1 is larger at the top and smaller at the bottom. The cross-sectional area of ​​the high-flow-rate roasting zone 101 is equal from top to bottom, and the cross-sectional area of ​​the low-flow-rate roasting zone 103 is equal from top to bottom, with the cross-sectional area of ​​the high-flow-rate roasting zone 101 being smaller than that of the low-flow-rate roasting zone 103. The bottom of the high-flow-rate roasting zone 101 is connected to the top of the low-flow-rate roasting zone 103. Ventilation holes are provided on the outer ring adjacent to the bottom of the high-flow-rate roasting zone 101 and the top of the low-flow-rate roasting zone 103.

[0143] Example 7

[0144] like Figure 4 As shown, Example 3 is repeated, except that the cross-sectional area inside the furnace body 1 is larger at the top and smaller at the bottom, and the cross-sectional areas of the high-speed fluidized roasting zone 101, the medium-flow-rate roasting zone 102, and the low-flow-rate roasting zone 103 gradually increase.

[0145] Application Example 1

[0146] The fluidized bed roasting of copper-zinc concentrate was carried out using the apparatus described in Example 4, and the specific steps are as follows:

[0147] 1) Grind 100 kg of copper-zinc concentrate to obtain 100 kg of copper-zinc concentrate powder; the average particle size is 0.85 mm;

[0148] 2) Fluidizing gas is introduced into the fluidization device, and the flow rate of the fluidizing gas introduced into the lower part of the high-velocity calcination zone is calculated:

[0149]

[0150] In the formula, m1 is the mass of copper-zinc concentrate with high copper content, and its value is 1.53 * 10. -6 kg; g is the acceleration due to gravity, with a value of 9.8 m / s². 2 ρ is the air density, taken as 1.225 kg / m³. 3 C1 is the resistance coefficient of copper-zinc concentrate with high copper content, with a value of 0.35; S is the cross-sectional area of ​​the fluidized bed roasting device, with a value of 0.0314 m². 2 S1 represents the projected area of ​​the high-copper-content copper-zinc concentrate perpendicular to the wind direction, with a value of 5.67 * 10. -7 m 2 ;

[0151] Calculate the gas flow rate drawn from the gas outlet at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone:

[0152]

[0153] In the formula, m2 is the mass of copper-zinc concentrate with medium copper content, and its value is taken as 9.07*10. -7 kg; g is the acceleration due to gravity, with a value of 9.8 m / s². 2 ρ is the air density, taken as 1.225 kg / m³. 3 C2 is the resistance coefficient of copper-zinc concentrate with medium copper content, with a value of 0.35; S is the cross-sectional area of ​​the fluidized bed roasting device, with a value of 0.0314 m². 2 S2 is the projected area of ​​a copper-zinc concentrate with medium copper content perpendicular to the wind direction, with a value of 5.67*10. -7 m 2 ;

[0154] The gas flow rate drawn from the gas outlet at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone is calculated as follows:

[0155]

[0156] In the formula, m3 represents the mass of copper-zinc concentrate with low copper content, and its value is 5.59 * 10. -7 kg; g is the acceleration due to gravity, with a value of 9.8 m / s². 2 ρ is the air density, taken as 1.225 kg / m³. 3C3 is the resistance coefficient of copper-zinc concentrate with low copper content, with a value of 0.35; S is the cross-sectional area of ​​the fluidized bed roasting device, with a value of 0.0314 m². 2 S3 represents the projected area of ​​a low-copper-content copper-zinc concentrate perpendicular to the wind direction, with a value of 5.67 * 10⁻⁶. -7 m 2 .

[0157] 3) The copper-zinc concentrate powder is added to a fluidized bed roasting device for roasting. During the fluidized bed roasting process, the flow rate G1 of the fluidizing gas introduced into the lower part of the high-velocity roasting zone is controlled to be 0.349 m³ / s. 3 / s, the gas flow rate G2 drawn from the gas outlet at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone is 0.08 m³ / s. 3 / s, the gas flow rate G3 drawn from the gas outlet at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone is 0.058 m³ / s. 3 The flow rate is controlled at 0.5 m³ / s, allowing high-copper-content copper-zinc concentrate to react in the high-flow-rate roasting zone, medium-copper-content copper-zinc concentrate in the medium-flow-rate roasting zone, and low-copper-content copper-zinc concentrate in the low-flow-rate roasting zone. After the reaction is complete, the gas flow rate from the gas outlet at the boundary between the medium-flow-rate and low-flow-rate roasting zones is first controlled to 0, then the gas flow rate from the gas outlet at the boundary between the high-flow-rate and medium-flow-rate roasting zones is controlled to 0, and finally the flow rate of the fluidizing gas introduced into the lower part of the high-flow-rate roasting zone is controlled to 0.5 m³ / s. 3 / s, all the roasted ore is discharged from the fluidization device to obtain 2.5 kg of CuO with a purity of 36.0% and 74.3 kg of ZnO with a purity of 59.3%.

[0158] Application Example 2

[0159] The fluidized bed roasting of copper-zinc concentrate was carried out using the apparatus described in Example 5, and the specific steps are as follows:

[0160] 1) Grind 100 kg of copper-zinc concentrate to obtain 100 kg of copper-zinc concentrate powder; the average particle size is 0.82 mm;

[0161] 2) Fluidizing gas is introduced into the fluidization device, and the flow rate of the fluidizing gas introduced into the lower part of the high-velocity calcination zone is calculated:

[0162]

[0163] In the formula, m1 is the mass of copper-zinc concentrate with high copper content, and its value is 1.38 * 10. -6 kg; g is the acceleration due to gravity, with a value of 9.8 m / s². 2 ρ is the air density, taken as 1.225 kg / m³. 3C1 is the resistance coefficient of copper-zinc concentrate with high copper content, with a value of 0.34; S4 is the minimum cross-sectional area in the high-flow-rate roasting zone, with a value of 0.0314 m². 2 S1 represents the projected area of ​​the high-copper-content copper-zinc concentrate perpendicular to the wind direction, with a value of 5.28 * 10⁻⁶. -7 m 2 ;

[0164] The gas flow rate at the vent at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone is controlled as follows:

[0165]

[0166] In the formula, m2 represents the mass of copper-zinc concentrate with medium copper content, and its value is 8.18 * 10. -7 kg; g is the acceleration due to gravity, with a value of 9.8 m / s². 2 ρ is the air density, taken as 1.225 kg / m³. 3 C2 is the resistance coefficient of copper-zinc concentrate with medium copper content, with a value of 0.34; S5 is the minimum cross-sectional area in the medium flow rate roasting zone, with a value of 0.0707 m². 2 S2 is the projected area of ​​a copper-zinc concentrate with medium copper content perpendicular to the wind direction, with a value of 5.28*10. -7 m 2 ;

[0167] The gas flow rate at the vent at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone is controlled as follows:

[0168]

[0169] In the formula, m3 represents the mass of copper-zinc concentrate with low copper content, and its value is 5.03 * 10. -7 kg; g is the acceleration due to gravity, with a value of 9.8 m / s². 2 ρ is the air density, taken as 1.225 kg / m³. 3 C3 is the resistance coefficient of copper-zinc concentrate with low copper content, with a value of 0.34; S6 is the minimum cross-sectional area in the low-flow-rate roasting zone, with a value of 0.126 m². 2 S3 represents the projected area of ​​a low-copper-content copper-zinc concentrate perpendicular to the wind direction, with a value of 5.28 * 10⁻⁶. -7 m 2 .

[0170] 3) The copper-zinc concentrate powder is added to a fluidized bed roasting device for roasting. During the fluidized bed roasting process, the flow rate G4 of the fluidizing gas introduced into the lower part of the high-velocity roasting zone is controlled to be 0.35 m³ / s. 3 The gas flow rate G5 at the vent at the boundary between the high-flow-rate roasting zone and the medium-flow-rate roasting zone is 0.3 m³ / s. 3The gas flow rate G6 at the vent at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone is 0.3 m³ / s. 3 The flow rate is controlled at a rate of / s, allowing high-copper-content copper-zinc concentrate to react in the high-flow-rate roasting zone, medium-copper-content copper-zinc concentrate in the medium-flow-rate roasting zone, and low-copper-content copper-zinc concentrate in the low-flow-rate roasting zone. After the reaction is complete, the gas flow rate at the vent at the boundary between the medium-flow-rate and low-flow-rate roasting zones is initially controlled at 0.5 m³ / s. 3 / s, then control the gas flow rate of the vent at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone to 1m³ / s. 3 / s, ultimately controlling the flow rate of the fluidizing gas introduced into the lower part of the high-velocity roasting zone to be 1m³ / s. 3 The calcined ore is discharged from the fluidization unit at a rate of / s. 1.9 kg of CuO (30% purity) and 76.8 kg of ZnO (62.5% purity) are obtained.

Claims

1. A fluidised roasting process of a copper-containing zinc concentrate characterised in that: The method comprises the following steps: 1) grinding the copper-zinc-containing concentrate to obtain a copper-zinc-containing concentrate powder; 2) introducing fluidizing gas into the fluidization device, and by controlling the introduction mode and amount of the fluidizing gas, a high-flow-rate roasting zone, a low-flow-rate roasting zone, and optionally a medium-flow-rate roasting zone between the high-flow-rate roasting zone and the low-flow-rate roasting zone are formed from bottom to top in the fluidization device; 3) adding the copper-zinc-containing concentrate powder into the fluidization device for roasting treatment, and during the fluidization roasting treatment, the flow rates of the fluidizing gas in the high-flow-rate roasting zone, the medium-flow-rate roasting zone, and the low-flow-rate roasting zone are controlled so that the copper-zinc-containing concentrate with a high copper content enters the high-flow-rate roasting zone for reaction, the copper-zinc-containing concentrate with a medium copper content enters the medium-flow-rate roasting zone for reaction, and the copper-zinc-containing concentrate with a low copper content enters the low-flow-rate roasting zone for reaction; after the reaction is completed, all the roasted ore materials are discharged from the fluidization device; The control of the flow rates of the fluidizing gas in the high-flow-rate roasting zone, the medium-flow-rate roasting zone, and the low-flow-rate roasting zone is as follows: according to the cross-sectional area of the fluidization device and the mass parameters of the copper-zinc-containing concentrate powder, the required air speed and air volume for making the copper-zinc-containing concentrate powder in each zone enter the fluidization roasting state are calculated, and the required air volume is introduced into the fluidization device according to the calculated results.

2. The method of claim 1, wherein: The upper and lower cross-sectional areas of the fluidization device are equal; the control of the flow rates of the fluidizing gas in the high-flow-rate roasting zone, the medium-flow-rate roasting zone, and the low-flow-rate roasting zone is as follows: gas outlets are arranged on the side walls at the junctions of the high-flow-rate roasting zone and the medium-flow-rate roasting zone and the medium-flow-rate roasting zone and the low-flow-rate roasting zone in the fluidization device; the fluidizing gas is first introduced into the lower part of the high-flow-rate roasting zone, and then the excess fluidizing gas in the high-flow-rate roasting zone and the medium-flow-rate roasting zone is led out through the gas outlets, so that the air speeds in the low-flow-rate roasting zone, the medium-flow-rate roasting zone, and the high-flow-rate roasting zone respectively meet the fluidization air speed requirements of the copper-zinc-containing concentrate with a low copper content, the copper-zinc-containing concentrate with a medium copper content, and the copper-zinc-containing concentrate with a high copper content.

3. The method of claim 2, wherein: The flow rate of the fluidizing gas introduced into the lower part of the high-flow-rate roasting zone is: ... (Formula 1) In the formula, G1 is the air volume introduced into the high flow rate roasting zone, m 3 / s; m1 is the mass of the high copper content copper-zinc concentrate, kg; g is the acceleration of gravity, which is 9.8 m / s 2 ; is the air density, kg / m 3 ; 1 is the resistance coefficient of the high copper content copper-zinc concentrate, which is 0.2-0.5; S is the cross-sectional area of the fluidized roasting device, m 2 ; S1 is the projected area of the high copper content copper-zinc concentrate perpendicular to the wind direction, m 2 ; Meanwhile, the flow rate of the gas led out by the gas outlet at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone is: ... (Formula 2) In the formula, G2 is the gas flow rate of the gas outlet at the junction of the high flow rate roasting zone and the medium flow rate roasting zone, m / s; m2 is the mass of the medium copper content copper-zinc concentrate, kg; g is the acceleration of gravity, which is 9.8 m / s 3 ; 2 ; is the air density, kg / m 3 ; 2 is the drag coefficient of the medium copper content copper-zinc concentrate, which is 0.2-0.5; and S is the cross-sectional area of the fluidized roasting device, m 2 ; S2 is the projected area of the copper-zinc concentrate with medium copper content perpendicular to the wind direction, m 2 ; Similarly, the flow rate of the gas led out by the gas outlet at the junction of the medium-flow-rate roasting zone and the low-flow-rate roasting zone is: … (Formula 3) G3 is the gas flow rate of the gas introduced from the gas outlet at the junction of the medium flow rate roasting zone and the low flow rate roasting zone, m / s; m is the mass of the low-copper-content copper-zinc-containing concentrate, kg; g is the acceleration of gravity, and is 9.8 m / s 3 ; 2 ; is the air density, kg / m 3 ; 3 is the drag coefficient of the low-copper-content copper-zinc-containing concentrate, and is 0.2-0.5; and S is the cross-sectional area of the fluidized roasting device, m 2 ; S3 is the projected area of the low copper content copper-zinc concentrate perpendicular to the wind direction, m 2 ; G1, G2, and G3 are controlled to respectively satisfy (Formula 1), (Formula 2), and (Formula 3), so that the copper-zinc-containing concentrate with a low copper content, the copper-zinc-containing concentrate with a medium copper content, and the copper-zinc-containing concentrate with a high copper content are respectively in stable fluidization states in the low-flow-rate roasting zone, the medium-flow-rate roasting zone, and the high-flow-rate roasting zone.

4. The method of claim 1, wherein: The cross-sectional area of the fluidization device increases from bottom to top; the size of the flow rate of the fluidizing gas in the high-flow-rate roasting zone, the medium-flow-rate roasting zone and the low-flow-rate roasting zone is calculated according to the difference between the cross-sectional area of the high-flow-rate roasting zone, the cross-sectional area of the medium-flow-rate roasting zone and the cross-sectional area of the low-flow-rate roasting zone, and the mass of the low-copper-content copper-zinc concentrate, the medium-copper-content copper-zinc concentrate and the high-copper-content copper-zinc concentrate and the projection area parameter perpendicular to the wind direction, and the wind speed in the high-flow-rate roasting zone, the medium-flow-rate roasting zone and the low-flow-rate roasting zone is calculated, and the amount of air introduced into the bottom of the high-flow-rate roasting zone is controlled according to the calculated wind speed.

5. The method of claim 4, wherein: Air holes are arranged on the side walls at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone in the fluidization device, and the side walls at the junction of the medium-flow-rate roasting zone and the low-flow-rate roasting zone, the flow rate of the gas introduced into the bottom of the high-flow-rate roasting zone and the flow rate of the gas introduced or discharged at the air holes are controlled, so that the copper-zinc concentrate is in a stable fluidization state.

6. The method of claim 5, wherein: The flow rate of the fluidizing gas introduced into the lower part of the high-flow-rate roasting zone is: … (Formula 4) In the formula, G4 is the air volume introduced into the lower part of the high flow rate roasting zone, m 3 ; m1 is the mass of the high copper content copper-zinc concentrate, kg; g is the acceleration of gravity, which is 9.8 m / s 2 ; ; and p is the air density, kg / m 3 ; 1 is the resistance coefficient of the high copper content copper-zinc concentrate, which is 0.2-0.5; and S4 is the minimum cross-sectional area in the high flow rate roasting zone, m 2 ; S1 is the projected area of the high copper content copper-zinc concentrate perpendicular to the wind direction, m 2 .

7. The method of claim 6, wherein: The flow rate of the gas at the air holes at the junction of the high-flow-rate roasting zone and the medium-flow-rate roasting zone is controlled to be: ... (Formula 5) G5 is the gas flow rate of the air hole at the junction of the high flow rate roasting zone and the medium flow rate roasting zone, m / s; m2 is the mass of the medium copper content copper-zinc concentrate, kg; g is the acceleration of gravity, and is 9.8 m / s 3 2 ; ρa is the air density, kg / m 3 ; 2 is the resistance coefficient of the medium copper content copper-zinc concentrate, and is 0.2-0.5; S5 is the minimum cross-sectional area in the medium flow rate roasting zone, m 2 ; S2 is the projection area of the medium copper content copper-zinc concentrate perpendicular to the wind direction, m 2 ; wherein, when G5 is less than 0, the absolute value of G5 is the gas flow rate of the air hole at the lower part of the medium flow rate roasting zone to the outside, and when G5 is greater than 0, the value of G5 is the gas flow rate of the air hole at the lower part of the medium flow rate roasting zone to the inside of the medium flow rate roasting zone;​ The flow rate of the gas at the air holes at the junction of the medium-flow-rate roasting zone and the low-flow-rate roasting zone is controlled to be: … (Formula 6) In the formula, G6 is the gas flow rate at the vent at the boundary between the medium-flow-rate roasting zone and the low-flow-rate roasting zone, in m. 3 / s; m3 is the mass of copper-zinc concentrate with low copper content, in kg; g is the acceleration due to gravity, taken as 9.8 m / s². 2 ; air density, kg / m³ 3 ; 3 represents the resistance coefficient of copper-zinc concentrate with low copper content, ranging from 0.2 to 0.5; S6 represents the minimum cross-sectional area in the low-flow-rate roasting zone, in meters. 2 S3 represents the projected area of ​​a medium-copper-content copper-zinc concentrate perpendicular to the wind direction, in meters. 2 Wherein, when G6 is less than 0, the absolute value of G6 is the gas flow rate that is exhausted outward through the vent at the bottom of the low flow rate roasting zone, and when G6 is greater than 0, the value of G6 is the gas flow rate that is introduced into the low flow rate roasting zone through the vent at the bottom of the low flow rate roasting zone.

8. The method of any one of claims 1-7, wherein: The particle size of the copper-zinc concentrate powder is less than 3 mm.

9. The method of claim 8, wherein: The particle size of the copper-zinc concentrate powder is less than 1 mm.

10. The method of claim 1, wherein: The copper-zinc concentrate powder is added to the fluidization device from the feed inlet at the top end of the fluidization device.

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