Multi-stage ore grinding reduction device and method for treating hard manganese ore by using multi-stage ore grinding reduction device

Abstract

The invention provides a multistage ore grinding reduction device which comprises a hearth, a gas-solid mixed outlet is formed in the upper portion of the side wall or the top wall of one side of the hearth, and a material inlet is formed in the side wall or the top wall of the other side of the hearth; a fluidized gas inlet is formed in the lower part of the side wall or the bottom wall of the hearth and is communicated with a reducing gas source; a crushing and grinding mechanism is arranged in the hearth; the device comprises a plurality of hearths which are sequentially connected in series, wherein an upper-stage gas-solid mixing outlet is communicated with a lower-stage material inlet; a sieve plate is arranged at each gas-solid mixing outlet, and the sieve pore diameter of the next stage of sieve plate is smaller than that of the previous stage of sieve plate. According to the invention, through the crushing mechanism and the sieve plate in the hearth, materials are fed into the hearth under different process conditions according to different size fractions, so that the problem of non-uniform grinding particle size caused by high hardness of the hard manganese ore is solved, uniform, accurate and efficient reduction of minerals with different size fractions is realized, and the energy consumption of the grinding reduction process is reduced.

Description

Technical Field

[0001] The invention relates to a grinding and reduction device, in particular to a multi-stage grinding and reduction device and a method for using the same for treating pyrolusite, belonging to the technical field of ore grinding and reduction. Background Art

[0002] Manganese ore is a scarce resource in my country, and pyrolusite is one of the main raw materials for manganese metallurgy. The chemical composition of pyrolusite is mMnO·MnO 2 ·nH 2 O, containing Mn45% to 60%. Due to the different oxidation degrees of low-valent manganese oxides, MnO and MnO 2 The ratio of MnO 2 The content of is usually 60-80%, MnO is 8-25%, H 2 O is 4-6%. The traditional treatment process of pyrolusite is to roast with coal as a reducing agent to reduce the MnO in pyrolusite. 2 The new two-ore roasting method also has many disadvantages. 2 Transformed into MnSO 4 , FeS 2 Transformed into Fe 2 O 3 Then it is leached with water and needs to be roasted for a long time under high sulfur-manganese ratio, which not only causes FeS 2 It cannot be fully utilized, and the slag volume is large and difficult to handle. There are also problems such as flue gas treatment.

[0003] The fluidized reduction roasting technology is used to produce manganese monoxide from pyrolusite. The product quality is stable and high, and there is basically no three wastes pollution. The power energy consumption is mainly electricity, and the reducing agent and heating fuel are mainly high-temperature waste gas resources for the current production of manganese alloys. This technology not only solves the problem of roasting manganese dioxide into manganese monoxide, but also uses the waste gas (carbon monoxide) of the electric furnace as energy to roast manganese dioxide, which belongs to clean energy production. In addition, if the roasted manganese monoxide is used as a raw material for the production of ferroalloys, it will also be possible to change the ferroalloy production process, that is, change the direct entry of manganese dioxide ore into the furnace, and use manganese monoxide to enter the furnace instead, so that the price reduction process of manganese dioxide is carried out outside the furnace, which greatly shortens the production time, significantly increases the output, and reduces the power consumption level.

[0004] Fluidized reduction process has attracted attention as a relatively efficient and reasonable technology for processing scleromanganese resources. Since the fluidized process requires the material particle size to be less than 1mm or even less than 0.1mm, the scleromanganese ore needs to be finely ground. However, scleromanganese ore has a high hardness. During the fine grinding process, it is necessary to ensure that the particle size of all materials is less than 0.1mm. Due to the selective effect of grinding, the easy-to-grind part has been ground finely, and the remaining is the hard-to-grind part with high hardness. In order to grind the hard-to-grind part of the material to the specified particle size, the grinding time can only be extended, and the easy-to-grind part is also continued to be ground to a finer particle size, resulting in over-grinding (for example: the particle size of some materials is 0.1mm, and the particle size of some materials is 0.002mm). Not only does it greatly increase the energy consumption level, but the over-fine material is not conducive to the subsequent fluidized reduction process, affecting product quality. Summary of the invention

[0005] In the prior art, in order to fluidize the pyrolusite, there are problems such as large differences in the grinding particle sizes of materials and over-grinding of the easily grinded parts during the grinding process, which is not conducive to the fluidized reduction process and will affect the product quality. The present invention proposes a multi-stage grinding reduction device, which is provided with a multi-stage furnace and adopts a method of grinding, screening and reducing at the same time. After manganese ores of different particle sizes enter the device, they enter different furnaces according to different particle sizes and are reduced under different process conditions, so as to achieve uniform, accurate and efficient reduction of pyrolusite of different particle sizes and reduce energy consumption.

[0006] According to a first embodiment of the present invention, a multi-stage grinding and reduction device is provided.

[0007] A multi-stage grinding reduction device, characterized in that the device comprises a furnace. A gas-solid mixing outlet is provided on the upper part of the side wall or the top wall on one side of the furnace, and a material inlet is provided on the side wall or the top wall on the other side of the furnace. A fluidizing gas inlet is provided on the lower part of the side wall or the bottom wall of the furnace, and the fluidizing gas inlet is connected to an external reducing gas source through a reducing gas delivery pipeline. A crushing and grinding mechanism is also provided inside the furnace.

[0008] The device includes a plurality of furnaces connected in series, and the gas-solid mixing outlet of the upper furnace is connected to the material inlet of the lower furnace through a material conveying pipeline. A sieve plate is provided at the gas-solid mixing outlet of each furnace, and the sieve hole diameter of the sieve plate in the lower furnace is smaller than the sieve hole diameter of the sieve plate in the upper furnace.

[0009] Preferably, the device comprises two or more furnaces connected in series from top to bottom, and adjacent furnaces are connected only by material conveying pipelines.

[0010] Preferably, the cross-sectional area of ​​the upper furnace is smaller than the cross-sectional area of ​​the lower furnace. Preferably, the cross-sectional area of ​​the upper furnace is 0.5 to 0.9 times the cross-sectional area of ​​the lower furnace. Preferably, the furnace is a cylindrical structure.

[0011] Preferably, the device comprises three levels of furnaces, namely, the first furnace, the second furnace and the third furnace from top to bottom. The diameters of the three levels of furnaces gradually increase from top to bottom. Preferably, the diameter ratio of the first furnace, the second furnace and the third furnace is 1:1.1-2:1.9-3.5, preferably 1:1.3-1.7:2-3.5.

[0012] Preferably, the diameter of the sieve holes of the sieve plate in the first furnace is 1.5-2.5 mm, the diameter of the sieve holes of the sieve plate in the second furnace is 0.5-1.5 mm, and the diameter of the sieve holes of the sieve plate in the third furnace is 0.1-0.5 mm.

[0013] Preferably, the device further comprises a gas-solid separation mechanism. A gas-solid mixing inlet is arranged on the side wall of the gas-solid separation mechanism, a material discharge port is arranged on the bottom wall, and a gas outlet is arranged on the top wall. The gas-solid mixing outlet of the upper furnace is connected to the gas-solid mixing inlet of the gas-solid separation mechanism through a material conveying pipeline. The material discharge port of the gas-solid separation mechanism is connected to the material inlet of the lower furnace.

[0014] Preferably, a gas-solid separation mechanism is provided on the outer side of each stage of the furnace. Preferably, a movable baffle that can completely cover the gas outlet is provided at the gas outlet of the gas-solid separation mechanism.

[0015] Preferably, each furnace is provided with an airflow control mechanism. The airflow control mechanism is arranged on one side of the furnace bottom and is connected to the reducing gas delivery pipe. Preferably, the number of airflow control mechanisms in each level of the furnace is equal to the number of furnace levels and is evenly distributed around the furnace bottom.

[0016] Preferably, the crushing and grinding mechanism includes a crushing and grinding roller, a crushing and grinding plate and a driving shaft. A crushing and grinding plate is provided at the bottom of each furnace, and a crushing and grinding roller is independently provided on each crushing and grinding plate. The driving shaft runs through all the furnaces along the central axis of all the furnaces from top to bottom, and is fixedly connected to the crushing and grinding roller in each furnace and movably connected to the crushing and grinding plate. A driving motor connected to the end of the driving shaft is also provided at the top of the uppermost furnace or the bottom of the lowermost furnace, and the driving motor can drive the crushing and grinding rollers in each furnace to roll on the crushing and grinding plate through the driving shaft. Preferably, the number of crushing and grinding rollers in each furnace increases gradually from top to bottom.

[0017] Preferably, the reducing gas source is a carbon monoxide gas source and / or a hydrogen gas source.

[0018] Preferably, a baffle is provided at the material inlet, the top of the baffle is connected to the upper end of the material inlet through a rotating shaft, the bottom of the baffle is lower than the lower end of the material inlet, and the lower part of the baffle can rotate unidirectionally toward the inside of the furnace with its top end as the axis.

[0019] According to a second embodiment of the present invention, a method for treating psilomelane is provided.

[0020] A method for treating pyrolusite, the method comprising the following steps:

[0021] 1) First, the pyrolusite is crushed to obtain crushed materials, and then the crushed materials are added from the material inlet of the uppermost furnace of the multi-stage grinding reduction device, and at the same time, reducing gas is introduced into each furnace from the fluidizing gas inlet;

[0022] 2) In the multi-stage grinding reduction device, large-particle psilomelane is ground and reduced simultaneously in the uppermost furnace, and the medium-particle psilomelane contained in the material and the ground medium-particle psilomelane are discharged from the gas-solid mixed outlet of the uppermost furnace along with the reducing airflow, and transported into the material inlet of the second-layer furnace through the material conveying pipeline, and so on, and the reduction product is finally discharged from the lowermost furnace.

[0023] Preferably, the method further comprises: 3) detecting various property parameters of the pyrolusite, calculating the optimal diameter of the furnace or the optimal wind speed in the furnace under the condition, and controlling the particle size of the pyrolusite in each furnace within a set range by the optimal diameter or wind speed of the furnace;

[0024] Preferably, the optimal diameter of the furnace under the above conditions is calculated as follows: The diameter of the furnace at each level is determined based on the material properties and the air volume, specifically:

[0025] According to the particle size of the material, the required minimum wind speed can be calculated:

[0026]

[0027] In the formula, m is the mass of the material, kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is air density, kg / m 3 ; C is the resistance coefficient of the material, which is 0.2-0.8; S is the projected area of ​​the material perpendicular to the wind direction, m 2 ;

[0028] Considering the shape of the material as a sphere, we can get:

[0029]

[0030] Where, π is the pi, which is 3.14; d is the material diameter, m;

[0031] In addition, the relationship between the wind speed in the furnace and the furnace diameter is:

[0032]

[0033] Where v is the wind speed inside the furnace, m / s; Q is the hourly air volume passing through the furnace, m 3 / h; D is the diameter of the furnace, m;

[0034] Substitute v = v min , from equation 1 to equation 3 we can get:

[0035]

[0036] According to Formula 4, the maximum diameter of each furnace level can be calculated through parameters such as air volume, material particle size and material mass.

[0037] Preferably, the optimal wind speed in the furnace under the above conditions is calculated as follows: the wind speed in the furnace at each level is calculated and determined according to the material properties and the furnace diameter, specifically:

[0038]

[0039] In the formula, v' is the minimum wind speed inside the furnace, m / s; m is the mass of the material, kg; g is the acceleration of gravity, which is 9.8 m / s 2 ; ρ is air density, kg / m 3 ; C is the resistance coefficient of the material, which is 0.2-0.8; S is the projected area of ​​the material perpendicular to the wind direction,

[0040] m 2 ;

[0041] Among them, the shape of the material is considered to be spherical:

[0042]

[0043] Where, π is the pi, which is 3.14; d is the material diameter, m;

[0044] According to equations 5 and 6, the minimum wind speed in the furnace can be calculated through parameters such as material particle size and material mass, and the wind speed in each level of the furnace can be controlled to be greater than the minimum wind speed.

[0045] Preferably, the multi-stage grinding reduction device includes three furnaces, which are the first furnace, the second furnace and the third furnace from top to bottom.

[0046] Preferably, the reaction temperature in the first furnace is 800-1000°C, the reaction temperature in the second furnace is 600-900°C, and the reaction temperature in the third furnace is 500-750°C; preferably, the reaction temperature in the first furnace is 850-950°C, the reaction temperature in the second furnace is 650-850°C, and the reaction temperature in the third furnace is 550-700°C.

[0047] In the present invention, a multi-stage grinding reduction device including a plurality of furnaces connected in series is proposed, and according to the size of the material particle size, materials with different particle sizes are respectively entered into different furnaces, and different process conditions are set inside each furnace to achieve uniform, accurate and efficient reduction of minerals of different particle sizes. Among them, the coarse-grained material requires a high reaction temperature and a long reaction time, and the fine-grained material requires a low reaction temperature and a short reaction time. Through temperature setting and gas fluidization speed regulation, the fine-grained material can be transported to the lower furnace, and the coarse-grained material is in the upper furnace, so as to achieve accurate reduction of materials of different particle sizes in different areas, and effectively reduce the energy consumption level. First, hard manganese ores of different particle sizes enter the fluidized reduction roasting device from the uppermost furnace, and the fluidized gas enters the device from the lower side wall or the bottom wall of each furnace. The material particle size of the upper furnace is coarse and the gas fluidization speed is fast. The relatively small particle size of the hard manganese ore can be blown out from the gas-solid mixing outlet of the uppermost furnace and enter the next furnace; the material particle size of the lower furnace is fine and the gas fluidization speed is slow. The material moves from the upper furnace to the lower furnace under the action of air flow. At the same time, the present invention sets sieve plates of different particle sizes at the gas-solid mixing outlet of the furnace to prevent large-size materials from entering the lower furnace. Raw materials of different particle sizes are selected by the particle size of the sieve and enter different positions of the furnace tube. While moving from top to bottom, the hard manganese ore undergoes a reduction reaction with the fluidizing gas, and the MnO 2 Converted into MnO, achieving simultaneous screening and reduction. The grinding media on the upper part of the furnace tube continuously grinds the coarse-grained materials and grinds them into fine particles. The obtained fine-grained materials pass through the sieve into the lower part of the furnace tube. Finally, all the materials are ground and blown out. The grinding and reduction processes are carried out simultaneously. After the reduction roasting is completed, the final material obtained can be used as a raw material for hydrometallurgy, reducing the energy consumption of the grinding reduction process. After the materials are ground, they are immediately discharged from the furnace without over-grinding.

[0048] In the present invention, the multi-stage furnace can be stacked in the vertical direction, or can be other structures in which the gas-solid mixing outlet of the upper furnace is connected to the material inlet of the lower furnace. Preferably, the multi-stage furnace is stacked in the vertical direction, and two adjacent furnaces are separated by a partition and are only connected through a material conveying pipeline. Preferably, the diameter of the furnace is limited, and the cross-sectional area of ​​the upper furnace is 0.5 to 0.9 times the area of ​​the lower furnace, so as to ensure that the air flow velocity in the upper furnace is greater than that in the lower furnace, and maintain the fluidization state of large-particle minerals.

[0049] In the present invention, according to application experience, when the device includes 3 levels of furnaces and the air volume in each level of the furnace is the same, the diameter ratio of the furnace from top to bottom is limited to 1:1.1~2:1.9~3.5, and the reduction gas flow rate in each level of the furnace is within the optimal range. More preferably, in view of the changes in material properties that may occur in practical applications, the present invention calculates the diameter of the furnace according to the material properties and the air volume on the basis of a large number of experiments, so that the reduction gas flow rate in each level of the furnace is within the optimal range, and minerals of different particle sizes have the best reduction conditions. Since each furnace is independent of each other, in the actual application process, only part of the furnace can be replaced, so that under the current air volume conditions, the diameter of each furnace can make the wind speed in the furnace within the optimal range. Alternatively, the minimum wind speed in the furnace can also be calculated, and the wind volume in a single furnace can be changed to control the wind speed of the fluidized gas in the furnace, so that the material in each level of the furnace is in a fluidized state. At the same time, the method of changing the air volume in a single furnace can also be used as a supplementary control means after calculating the furnace diameter.

[0050] In the present invention, a gas-solid separation mechanism is provided, and the small-size minerals and reducing gas in the upper furnace enter the gas-solid separation mechanism through the material conveying pipeline, and the material then enters the lower furnace through the discharge port. Preferably, a movable baffle is provided at the gas outlet of the gas-solid separation mechanism, and when the reducing gas flow rate in the furnace is too fast, part of the reducing gas in the material conveying pipeline is discharged from the gas outlet of the gas-solid separation mechanism to adjust the gas flow rate in the furnace.

[0051] In the present invention, an airflow control mechanism is provided. When the wind speed in the furnace needs to be changed, the amount of gas blown into the furnace is changed by using the airflow control mechanism. In addition, when the material particles in the furnace need to be discharged through the gas-solid mixing outlet, the sieve plate at the gas-solid mixing outlet can also be removed, and the airflow control mechanism can be used to supplement air and blow out the material in the furnace, thereby realizing full automation of the feeding and discharging process.

[0052] In the present invention, parameters such as the diameter of each furnace stage and the sieve hole diameter of each furnace sieve plate can be determined according to parameters in the actual production process such as the number of furnace stages, and then the furnace diameter or the wind speed in the furnace can be determined according to the required material particle size. For example, when the device includes two levels of furnaces, the diameter of the sieve holes of the first furnace sieve plate is 1.5-2.5mm, and the diameter of the sieve holes of the second furnace sieve plate is 0.2-1.2mm; when the device includes three levels of furnaces, the diameter of the sieve holes of the first furnace sieve plate is 1.5-2.5mm, the diameter of the sieve holes of the second furnace sieve plate is 0.5-1.5mm, and the diameter of the sieve holes of the third furnace sieve plate is 0.1-0.5mm; when the device includes four levels of furnaces, the diameter of the sieve holes of the first furnace sieve plate is 1.8-2.5mm, the diameter of the sieve holes of the second furnace sieve plate is 0.5-1.8mm, the diameter of the sieve holes of the third furnace sieve plate is 0.3-0.5mm, and the diameter of the sieve holes of the fourth furnace sieve plate is 0.1-0.3mm.

[0053] In the present invention, a baffle which can only rotate unidirectionally toward the interior of the furnace is arranged at the material inlet of the furnace to prevent the reducing airflow in the furnace from flowing out from the material inlet, and also facilitates the smooth entry of the material.

[0054] In the present invention, the multi-stage grinding reduction device is used to process pyrolusite, and the process parameters in the multi-stage furnace are determined according to the number of furnace stages. For example, when the device includes three furnace stages, the optimal temperature range in each furnace stage is: the reaction temperature in the first furnace stage is 800-1000°C, the reaction temperature in the second furnace stage is 600-900°C, and the reaction temperature in the third furnace stage is 500-750°C.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] 1. The multi-stage grinding reduction device provided by the present invention utilizes the difference in reaction rates of ores of different particle sizes, and feeds materials into furnaces with different process conditions according to different particle sizes through the crushing mechanism and screen plate inside the furnace, thereby solving the problem of uneven grinding particle size caused by the high hardness of hard manganese ore, achieving uniform, accurate and efficient reduction of minerals of different particle sizes, and reducing the energy consumption of the grinding reduction process.

[0057] 2. The present invention provides a multi-stage grinding reduction device which limits the diameter of each furnace stage. The diameter of each furnace stage can also be calculated based on the material properties. The flow rate of the reducing gas in each furnace stage is within the optimal range, so that minerals of different particle sizes have the best reduction conditions.

[0058] 3. The present invention provides a method for treating pyrolusite using a multi-stage grinding reduction device, and limits the process parameters in each stage of the furnace to ensure the quality of the reduction product. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 A schematic structural diagram of a multi-stage grinding reduction device provided by the present invention.

[0060] Figure 2 This is an AA cross-sectional view of a multi-stage grinding reduction device provided by the present invention.

[0061] Figure 3 This is a BB cross-sectional view of a multi-stage grinding reduction device provided by the present invention.

[0062] Figure 4 This is a CC cross-sectional view of a multi-stage grinding reduction device provided by the present invention.

[0063] Figure 5 Another structural schematic diagram of a multi-stage grinding reduction device provided by the present invention.

[0064] Figure numerals: 1: furnace; 2: gas-solid mixing outlet; 3: material inlet; 4: fluidizing gas inlet; 5: reducing gas delivery pipe; 6: reducing gas source; 7: crushing and grinding mechanism; 701: crushing and grinding roller; 702: crushing and grinding plate; 703: driving shaft; 704: driving motor; 8: sieve plate; 9: gas-solid separation mechanism. DETAILED DESCRIPTION

[0065] The technical solution of the present invention is illustrated below by way of example, and the scope of protection requested by the present invention includes but is not limited to the following embodiments.

[0066] According to a first embodiment of the present invention, a multi-stage grinding and reduction device is provided.

[0067] A multi-stage grinding reduction device, characterized in that the device comprises a furnace 1. A gas-solid mixing outlet 2 is provided on the upper side wall or the top wall on one side of the furnace 1, and a material inlet 3 is provided on the side wall or the top wall on the other side of the furnace 1. A fluidizing gas inlet 4 is provided on the lower side wall or the bottom wall of the furnace 1, and the fluidizing gas inlet 4 is connected to an external reducing gas source 6 through a reducing gas delivery pipe 5. A crushing and grinding mechanism 7 is also provided inside the furnace 1.

[0068] The device includes a plurality of furnaces 1 connected in series, and the gas-solid mixing outlet 2 of the upper furnace 1 is connected to the material inlet 3 of the lower furnace 1 through a material conveying pipeline. A sieve plate 8 is provided at the gas-solid mixing outlet 2 of each furnace 1, and the sieve hole diameter of the sieve plate 8 in the lower furnace 1 is smaller than the sieve hole diameter of the sieve plate 8 in the upper furnace 1.

[0069] Preferably, the device comprises two or more furnaces 1 connected in series from top to bottom, and adjacent furnaces 1 are connected only by material conveying pipelines.

[0070] Preferably, the cross-sectional area of ​​the upper furnace 1 is smaller than the cross-sectional area of ​​the lower furnace 1. Preferably, the cross-sectional area of ​​the upper furnace 1 is 0.5 to 0.9 times the cross-sectional area of ​​the lower furnace 1. Preferably, the furnace 1 is a cylindrical structure.

[0071] Preferably, the device comprises three levels of furnaces 1, namely, the first furnace, the second furnace and the third furnace from top to bottom. The diameters of the three levels of furnaces gradually increase from top to bottom. Preferably, the diameter ratio of the first furnace, the second furnace and the third furnace is 1:1.1-2:1.9-3.5, preferably 1:1.3-1.7:2-3.5.

[0072] Preferably, the diameter of the sieve holes of the sieve plate 8 in the first furnace is 1.5-2.5 mm, the diameter of the sieve holes of the sieve plate 8 in the second furnace is 0.5-1.5 mm, and the diameter of the sieve holes of the sieve plate 8 in the third furnace is 0.1-0.5 mm.

[0073] Preferably, the device further comprises a gas-solid separation mechanism 9. A gas-solid mixing inlet is arranged on the side wall of the gas-solid separation mechanism 9, a material discharge port is arranged on the bottom wall thereof, and a gas outlet is arranged on the top wall. The gas-solid mixing outlet 2 of the upper furnace 1 is connected to the gas-solid mixing inlet of the gas-solid separation mechanism 9 through a material conveying pipeline. The material discharge port of the gas-solid separation mechanism 9 is connected to the material inlet 3 of the lower furnace 1.

[0074] Preferably, a gas-solid separation mechanism 9 is provided on the outer side of each stage of the furnace 1. Preferably, a movable baffle which can completely cover the gas outlet is provided at the gas outlet of the gas-solid separation mechanism 9.

[0075] Preferably, each furnace 1 is provided with an airflow control mechanism. The airflow control mechanism is arranged on one side of the bottom of the furnace 1 and is connected to the reducing gas delivery pipe 5. Preferably, the number of airflow control mechanisms in each stage of the furnace 1 is equal to the number of stages of the furnace 1, and is evenly distributed around the bottom of the furnace 1.

[0076] Preferably, the crushing and grinding mechanism 7 includes a crushing and grinding roller 701, a crushing and grinding plate 702 and a driving shaft 703. A crushing and grinding plate 702 is provided at the bottom of each furnace 1, and a crushing and grinding roller 701 is independently provided on each crushing and grinding plate 702. The driving shaft 703 runs through all the furnaces 1 along the central axis of all the furnaces 1 from top to bottom, and is fixedly connected to the crushing and grinding roller 701 in each furnace 1 and movably connected to the crushing and grinding plate 702. A driving motor 704 connected to the end of the driving shaft 703 is also provided at the top of the uppermost furnace 1 or the bottom of the lowermost furnace 1. The driving motor 704 can drive the crushing and grinding roller 701 in each furnace 1 to roll on the crushing and grinding plate 702 through the driving shaft 703. Preferably, the number of crushing and grinding rollers 701 in each furnace 1 gradually increases from top to bottom.

[0077] Preferably, the reducing gas source 6 is a carbon monoxide gas source and / or a hydrogen gas source.

[0078] Preferably, a baffle is provided at the material inlet 3, the top of the baffle is connected to the upper end of the material inlet 3 through a rotating shaft, the bottom of the baffle is lower than the lower end of the material inlet 3, and the lower part of the baffle can rotate unidirectionally toward the inside of the furnace 1 with its top end as the axis.

[0079] According to a second embodiment of the present invention, a method for treating psilomelane is provided.

[0080] A method for treating pyrolusite, the method comprising the following steps:

[0081] 1) First, the pyrolusite is crushed to obtain crushed materials, and then the crushed materials are added from the material inlet of the uppermost furnace of the multi-stage grinding reduction device, and at the same time, reducing gas is introduced into each furnace from the fluidizing gas inlet;

[0082] 2) In the multi-stage grinding reduction device, large-particle psilomelane is ground and reduced simultaneously in the uppermost furnace, and the medium-particle psilomelane contained in the material and the ground medium-particle psilomelane are discharged from the gas-solid mixed outlet of the uppermost furnace along with the reducing airflow, and transported into the material inlet of the second-layer furnace through the material conveying pipeline, and so on, and the reduction product is finally discharged from the lowermost furnace.

[0083] Preferably, the method further comprises: 3) detecting various property parameters of the pyrolusite, calculating the optimal diameter of the furnace or the optimal wind speed in the furnace under the condition, and controlling the particle size of the pyrolusite in each furnace within a set range by the optimal diameter or wind speed of the furnace;

[0084] Preferably, the optimal diameter of the furnace under the above conditions is calculated as follows: The diameter of the furnace at each level is determined based on the material properties and the air volume, specifically:

[0085] According to the particle size of the material, the required minimum wind speed can be calculated:

[0086]

[0087] In the formula, m is the mass of the material, kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is air density, kg / m 3 ; C is the resistance coefficient of the material, which is 0.2-0.8; S is the projected area of ​​the material perpendicular to the wind direction, m 2 ;

[0088] Considering the shape of the material as a sphere, we can get:

[0089]

[0090] Where, π is the pi, which is 3.14; d is the material diameter, m;

[0091] In addition, the relationship between the wind speed in the furnace and the furnace diameter is:

[0092]

[0093] Where v is the wind speed inside the furnace, m / s; Q is the hourly air volume passing through the furnace, m 3 / h; D is the diameter of the furnace, m;

[0094] Substitute v = v min , from equation 1 to equation 3 we can get:

[0095]

[0096] According to Formula 4, the maximum diameter of each furnace level can be calculated through parameters such as air volume, material particle size and material mass.

[0097] Preferably, the optimal wind speed in the furnace under the above conditions is calculated as follows: the wind speed in the furnace at each level is calculated and determined according to the material properties and the furnace diameter, specifically:

[0098]

[0099] In the formula, v' is the minimum wind speed inside the furnace, m / s; m is the mass of the material, kg; g is the acceleration of gravity, which is 9.8 m / s 2 ; ρ is air density, kg / m 3 ; C is the resistance coefficient of the material, which is 0.2-0.8; S is the projected area of ​​the material perpendicular to the wind direction,

[0100] m 2

[0101] Among them, the shape of the material is considered to be spherical:

[0102]

[0103] Where, π is the pi, which is 3.14; d is the material diameter, m;

[0104] According to equations 5 and 6, the minimum wind speed in the furnace can be calculated through parameters such as material particle size and material mass, and the wind speed in each level of the furnace can be controlled to be greater than the minimum wind speed.

[0105] Preferably, the reaction temperature in the first furnace is 800-1000°C, the reaction temperature in the second furnace is 600-900°C, and the reaction temperature in the third furnace is 500-750°C; preferably, the reaction temperature in the first furnace is 850-950°C, the reaction temperature in the second furnace is 650-850°C, and the reaction temperature in the third furnace is 550-700°C.

[0106] Example 1

[0107] A multi-stage grinding reduction device, characterized in that the device comprises a furnace 1. A gas-solid mixing outlet 2 is provided on the upper part of the side wall on one side of the furnace 1, and a material inlet 3 is provided on the side wall on the other side of the furnace 1. A fluidizing gas inlet 4 is provided on the bottom wall of the furnace 1, and the fluidizing gas inlet 4 is connected to an external reducing gas source 6 through a reducing gas delivery pipe 5. A crushing and grinding mechanism 7 is also provided inside the furnace 1.

[0108] The device includes three furnaces 1 connected in series, and the gas-solid mixing outlet 2 of the upper furnace 1 is connected to the material inlet 3 of the lower furnace 1 through a material conveying pipeline. A sieve plate 8 is provided at the gas-solid mixing outlet 2 of each furnace 1, and the sieve hole diameter of the sieve plate 8 in the lower furnace 1 is smaller than the sieve hole diameter of the sieve plate 8 in the upper furnace 1.

[0109] Example 2

[0110] Example 1 is repeated, except that three furnaces 1 are connected in series from top to bottom, and adjacent furnaces 1 are connected only by material conveying pipelines.

[0111] Example 3

[0112] Example 2 is repeated, except that the cross-sectional area of ​​the upper furnace 1 is smaller than that of the lower furnace 1. The cross-sectional area of ​​the first furnace is 0.88 times that of the second furnace, and the cross-sectional area of ​​the second furnace is 0.83 of that of the third furnace. The furnace 1 is a cylindrical structure.

[0113] Example 4

[0114] The embodiment 3 is repeated, except that the furnace 1 of the three levels is sequentially the first furnace, the second furnace and the third furnace from top to bottom. The diameter of the three-level furnace increases gradually from top to bottom.

[0115] The diameter of the sieve holes of the sieve plate 8 in the first furnace is 1.6 mm, the diameter of the sieve holes of the sieve plate 8 in the second furnace is 0.7 mm, and the diameter of the sieve holes of the sieve plate 8 in the third furnace is 0.2 mm.

[0116] Example 5

[0117] Example 3 is repeated, except that the device further includes a gas-solid separation mechanism 9. A gas-solid mixing inlet is provided on the side wall of the gas-solid separation mechanism 9, a material discharge port is provided on the bottom wall thereof, and a gas outlet is provided on the top wall. The gas-solid mixing outlet 2 of the upper furnace 1 is connected to the gas-solid mixing inlet of the gas-solid separation mechanism 9 through a material conveying pipeline. The material discharge port of the gas-solid separation mechanism 9 is connected to the material inlet 3 of the lower furnace 1.

[0118] Example 6

[0119] The embodiment 5 is repeated, except that a gas-solid separation mechanism 9 is provided on the outer side of each stage of the furnace 1. A movable baffle which can completely cover the gas outlet is provided at the gas outlet of the gas-solid separation mechanism 9.

[0120] Example 7

[0121] Example 6 is repeated, except that an airflow control mechanism is provided in each furnace 1. The airflow control mechanism is arranged on one side of the bottom of the furnace 1 and is connected to the reducing gas delivery pipe 5. The number of airflow control mechanisms in each stage of the furnace 1 is equal to the number of stages of the furnace 1, that is, one airflow control mechanism is provided in the first furnace, two airflow control mechanisms are provided in the second furnace, and three airflow control mechanisms are provided in the third furnace, and they are evenly distributed around the bottom of the furnace 1.

[0122] Example 8

[0123] Example 7 is repeated, except that the crushing and grinding mechanism 7 includes a crushing and grinding roller 701, a crushing and grinding plate 702 and a driving shaft 703. A crushing and grinding plate 702 is provided at the bottom of each furnace 1, and a crushing and grinding roller 701 is independently provided on each crushing and grinding plate 702. The driving shaft 703 penetrates all the furnaces 1 along the central axis of all the furnaces 1 from top to bottom, and is fixedly connected to the crushing and grinding roller 701 in each furnace 1 and movably connected to the crushing and grinding plate 702. A driving motor 704 connected to the end of the driving shaft 703 is also provided at the top of the uppermost furnace 1. The driving motor 704 can drive the crushing and grinding roller 701 in each furnace 1 to roll on the crushing and grinding plate 702 through the driving shaft 703. The number of crushing and grinding rollers 701 in each furnace 1 gradually increases from top to bottom, and the number of crushing and grinding rollers 701 in each furnace 1 is equal to the number of furnaces 1 + 1.

[0124] Example 9

[0125] Example 8 is repeated, except that the reducing gas source 6 is a carbon monoxide gas source and a hydrogen gas source.

[0126] Example 10

[0127] Repeat Example 9, except that a baffle is provided at the material inlet 3, the top of the baffle is connected to the upper end of the material inlet 3 via a rotating shaft, the bottom of the baffle is lower than the lower end of the material inlet 3, and the lower part of the baffle can rotate unidirectionally toward the inside of the furnace 1 with its top end as the axis.

[0128] Application Example 1

[0129] A method for treating pyrolusite, comprising calculating the diameter of each furnace in the multi-stage grinding reduction device described in Example 10, and treating pyrolusite using the multi-stage grinding reduction device described in Example 10, the method comprising the following steps:

[0130] 1) First, 10 kg of hard manganese ore is crushed to obtain 10 kg of crushed material, and then the crushed material is added from the material inlet of the uppermost furnace of the multi-stage grinding reduction device, and at the same time, reducing gas is introduced into each furnace from the fluidizing gas inlet;

[0131] 2) In the multi-stage grinding reduction device, large-particle psilomelane is ground and reduced simultaneously in the first furnace, medium-particle psilomelane contained in the material and the ground medium-particle psilomelane is discharged from the gas-solid mixed outlet of the first furnace along with the reducing airflow, and is transported into the material inlet of the second furnace through the material conveying pipeline, small-particle psilomelane contained in the material and the ground small-particle psilomelane is discharged from the gas-solid mixed outlet of the second furnace along with the reducing airflow, and enters the material inlet of the third furnace, and finally the reduction product is discharged from the third furnace.

[0132] Among them, various property parameters of pyrolusite are detected, the optimal diameter of the furnace under this condition is calculated, and the furnace of appropriate size is selected through the optimal diameter of the furnace, so as to control the particle size of pyrolusite in each furnace within the set range.

[0133] In the first furnace:

[0134]

[0135] m 1 is the mass of a single large particle material ground and reduced in the first furnace, and its value is 6.43*10 -6 kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is the air density, which is 1.29 kg / m 3 ; C 1 is the resistance coefficient of large particles, which is 0.7; Π is the pi, which is 3.14; Q is the air volume passing through the furnace per hour, which is 180000m 3 / h;d 1 is the diameter of large particle materials, which is 1.6mm;

[0136] According to the above formula, D 1 =2.76m.

[0137] Similarly, in the second furnace:

[0138]

[0139] m 2 is the mass of a single medium-sized particle material ground and reduced in the second furnace, and its value is 5.12*10 -7 kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is the air density, which is 1.29 kg / m 3 ; C 2 is the resistance coefficient of medium-sized particles, which is 0.5; Π is the pi, which is 3.14; Q is the air volume per hour passing through the furnace, which is 180,000 m 3 / h;d 2 is the diameter of the medium-sized particle material, which is 0.7 mm;

[0140] According to the above formula, D 2 =3.12m.

[0141] In the third furnace:

[0142]

[0143] m 3is the mass of small particles ground and reduced in the third furnace, and its value is 1.26*10 -8 kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is the air density, which is 1.29 kg / m 3 ; C 3 is the resistance coefficient of small particles, which is 0.3; Π is the pi, which is 3.14; Q is the air volume per hour passing through the furnace, which is 180000m 3 / h;d 3 is the diameter of small particles, which is 0.2mm;

[0144] According to the above formula, D 3 =3.76m.

[0145] According to the above calculations, the diameter of the first furnace is selected to be 2.76m, the diameter of the second furnace is selected to be 3.12m, and the diameter of the third furnace is selected to be 3.76m.

[0146] Application Example 2

[0147] A method for treating pyrolusite, using the multi-stage grinding reduction device described in Example 10 to treat pyrolusite, the method comprising the following steps:

[0148] 1) First, 10 kg of hard manganese ore is crushed to obtain 10 kg of crushed material, and then the crushed material is added from the material inlet of the uppermost furnace of the multi-stage grinding reduction device, and at the same time, reducing gas is introduced into each furnace from the fluidizing gas inlet;

[0149] 2) In the multi-stage grinding reduction device, large-particle psilomelane is ground and reduced simultaneously in the first furnace, medium-particle psilomelane contained in the material and the ground medium-particle psilomelane is discharged from the gas-solid mixed outlet of the first furnace along with the reducing airflow, and is transported into the material inlet of the second furnace through the material conveying pipeline, small-particle psilomelane contained in the material and the ground small-particle psilomelane is discharged from the gas-solid mixed outlet of the second furnace along with the reducing airflow, and enters the material inlet of the third furnace, and finally the reduction product is discharged from the third furnace.

[0150] 3) Detect various property parameters of pyrolusite, calculate the optimal wind speed in the furnace under this condition, and control the particle size of pyrolusite in each furnace within the set range by changing the wind speed in the furnace.

[0151] Among them, the wind speed in the first furnace is:

[0152]

[0153] v 1 ′is the minimum wind speed inside the furnace, m / s; m 1 is the mass of the large particles ground and reduced in the first furnace, which is 6.43*10 -6 kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is the air density, which is 1.29 kg / m 3 ; C 1 is the resistance coefficient of large particle materials, which is 0.7; Π is the circumference of a circle, which is 3.14; d 1 is the diameter of large particle materials, which is 1.6mm;

[0154] The wind speed in the second furnace is:

[0155]

[0156] v 2 ′ is the minimum wind speed inside the furnace, m / s; m 2 is the mass of the medium-sized particles ground and reduced in the second furnace, which is 5.12*10 -7 kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is the air density, which is 1.29 kg / m 3 ; C 2 is the resistance coefficient of medium-sized particles, which is 0.5; Π is the circumference of a circle, which is 3.14; d 2 is the diameter of the medium-sized particle material, which is 0.7 mm;

[0157] The wind speed in the third furnace is:

[0158]

[0159] v 3 ′ is the minimum wind speed inside the furnace, m / s; m 3 is the mass of small particles ground and reduced in the third furnace, and its value is 1.26*10 -8 kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is the air density, which is 1.29 kg / m 3 ; C 3 is the resistance coefficient of small particle materials, which is 0.3; Π is the circumference of a circle, which is 3.14; d 3 is the diameter of small particles, which is 0.2mm;

[0160] According to the above calculation, the wind speed of the first furnace is selected to be 8.3m / s, the wind speed of the second furnace is selected to be 6.4m / s, and the wind speed of the third furnace is selected to be 4.5m / s.

Claims

1. A multi-stage grinding reduction device, characterized in that: The device comprises a furnace (1); a gas-solid mixing outlet (2) is provided on the upper part of the side wall or the top wall of one side of the furnace (1); a material inlet (3) is provided on the side wall or the top wall of the other side of the furnace (1); a fluidizing gas inlet (4) is provided on the lower part of the side wall or the bottom wall of the furnace (1); the fluidizing gas inlet (4) is connected to an external reducing gas source (6) through a reducing gas delivery pipe (5); and a crushing and grinding mechanism (7) is also provided inside the furnace (1); The device comprises a plurality of furnaces (1) connected in series, wherein the gas-solid mixing outlet (2) of the upper furnace (1) and the material inlet (3) of the lower furnace (1) are connected via a material conveying pipeline; a sieve plate (8) is provided at the gas-solid mixing outlet (2) of each furnace (1), and the sieve hole diameter of the sieve plate (8) in the lower furnace (1) is smaller than the sieve hole diameter of the sieve plate (8) in the upper furnace (1).

2. The device according to claim 1, characterized in that: The device comprises two or more furnaces (1) which are connected in series from top to bottom, and adjacent furnaces (1) are connected only through material conveying pipelines; Preferably, the cross-sectional area of ​​the upper furnace (1) is smaller than the cross-sectional area of ​​the lower furnace (1); preferably, the cross-sectional area of ​​the upper furnace (1) is 0.5 to 0.9 times the cross-sectional area of ​​the lower furnace (1); preferably, the furnace (1) is a cylindrical structure.

3. The device according to claim 2, characterized in that: The device comprises three levels of furnaces (1), which are the first furnace, the second furnace and the third furnace from top to bottom; the diameters of the three levels of furnaces gradually increase from top to bottom; preferably, the ratio of the diameters of the first furnace, the second furnace and the third furnace is 1:1.1-2:1.9-3.5, preferably 1:1.3-1.7:2-3.5; Preferably, the diameter of the sieve holes of the sieve plate (8) in the first furnace is 1.5 to 2.5 mm, the diameter of the sieve holes of the sieve plate (8) in the second furnace is 0.5 to 1.5 mm, and the diameter of the sieve holes of the sieve plate (8) in the third furnace is 0.1 to 0.5 mm.

4. The device according to any one of claims 1 to 3, characterized in that: The device further comprises a gas-solid separation mechanism (9); a gas-solid mixing inlet is arranged on the side wall of the gas-solid separation mechanism (9), a material discharge port is arranged on the bottom wall, and a gas outlet is arranged on the top wall; the gas-solid mixing outlet (2) of the upper furnace (1) is connected to the gas-solid mixing inlet of the gas-solid separation mechanism (9) through a material conveying pipeline; the material discharge port of the gas-solid separation mechanism (9) is connected to the material inlet (3) of the lower furnace (1); Preferably, a gas-solid separation mechanism (9) is provided on the outer side of each stage of the furnace (1); preferably, a movable baffle that can completely cover the gas outlet is provided at the gas outlet of the gas-solid separation mechanism (9).

5. The device according to any one of claims 1 to 4, characterized in that: Each furnace (1) is provided with an airflow control mechanism; the airflow control mechanism is arranged on one side of the bottom of the furnace (1) and is connected to the reducing gas delivery pipe (5); preferably, the number of airflow control mechanisms in each level of the furnace (1) is equal to the number of levels of the furnace (1), and is evenly distributed around the bottom of the furnace (1).

6. The device according to any one of claims 1 to 5, characterized in that: The crushing and grinding mechanism (7) comprises a crushing and grinding roller (701), a crushing and grinding plate (702) and a driving shaft (703); a crushing and grinding plate (702) is arranged at the bottom of each furnace (1), and a crushing and grinding roller (701) is independently arranged on each crushing and grinding plate (702); the driving shaft (703) passes through all the furnaces (1) from top to bottom along the central axis of all the furnaces (1), and is fixedly connected to the crushing and grinding roller (701) in each furnace (1). A driving motor (704) connected to the end of the driving shaft (703) is also provided at the top of the uppermost furnace (1) or the bottom of the lowermost furnace (1), and is movably connected to the crushing and grinding plate (702). The driving motor (704) can drive the crushing and grinding rollers (701) in each furnace (1) to roll on the crushing and grinding plate (702) via the driving shaft (703); preferably, the number of crushing and grinding rollers (701) in each furnace (1) gradually increases from top to bottom.

7. The device according to any one of claims 2 to 6, characterized in that: The reducing gas source (6) is a carbon monoxide gas source and / or a hydrogen gas source; and / or A baffle is provided at the material inlet (3), the top end of the baffle is connected to the upper end of the material inlet (3) via a rotating shaft, the bottom end of the baffle is lower than the lower end of the material inlet (3), and the lower part of the baffle can be unidirectionally rotated toward the inside of the furnace (1) with its top end as an axis.

8. A method for treating psilomelane using the device according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: 1) Firstly, pyrolusite is crushed to obtain crushed material, and then the crushed material is added from the material inlet of the uppermost furnace of the multi-stage grinding reduction device according to any one of claims 1 to 7, and at the same time, reducing gas is introduced into each furnace from the fluidizing gas inlet; 2) In the multi-stage grinding reduction device, large-particle psilomelane is ground and reduced simultaneously in the uppermost furnace, and the medium-particle psilomelane contained in the material and the ground medium-particle psilomelane are discharged from the gas-solid mixed outlet of the uppermost furnace along with the reducing airflow, and transported into the material inlet of the second-layer furnace through the material conveying pipeline, and so on, and the reduction product is finally discharged from the lowermost furnace.

9. The method according to claim 8, characterized in that: The method further comprises: 3) detecting various property parameters of the pyrolusite, calculating the optimal diameter of the furnace or the optimal wind speed in the furnace under the condition, and controlling the particle size of the pyrolusite in each furnace within a set range by using the optimal diameter or wind speed of the furnace; Preferably, the optimal diameter of the furnace under the above conditions is calculated as follows: The diameter of the furnace at each level is determined based on the material properties and the air volume, specifically: According to the particle size of the material, the required minimum wind speed can be calculated: In the formula, m is the mass of the material, kg; g is the acceleration due to gravity, which is 9.8 m / s 2 ; ρ is air density, kg / m 3 ; C is the resistance coefficient of the material, which is 0.2-0.8; S is the projected area of ​​the material perpendicular to the wind direction, m 2 ; Considering the shape of the material as a sphere, we can get: Where, π is the pi, which is 3.14; d is the material diameter, m; In addition, the relationship between the wind speed in the furnace and the furnace diameter is: Where v is the wind speed inside the furnace, m / s; Q is the hourly air volume passing through the furnace, m 3 / h; D is the diameter of the furnace, m; Substitute v = v min , from equation 1 to equation 3 we can get: According to formula 4, the maximum diameter of each furnace can be calculated by parameters such as air volume, material particle size and material mass; or The optimal wind speed in the furnace under this condition is calculated as follows: The wind speed in the furnace at each level is calculated and determined based on the material properties and the furnace diameter, specifically: In the formula, v' is the minimum wind speed inside the furnace, m / s; m is the mass of the material, kg; g is the acceleration of gravity, which is 9.8 m / s 2 ; ρ is air density, kg / m 3 ; C is the resistance coefficient of the material, which is 0.2-0.8; S is the projected area of ​​the material perpendicular to the wind direction, m 2 Among them, the shape of the material is considered to be spherical: Where, π is the pi, which is 3.14; d is the material diameter, m; According to Formula 5 and Formula 6, the minimum wind speed in the furnace can be calculated through parameters such as material particle size and material mass, and the wind speed in each level of the furnace can be controlled to be greater than the minimum wind speed.

10. The method according to claim 9, characterized in that: The multi-stage grinding reduction device comprises three furnaces, which are the first furnace, the second furnace and the third furnace from top to bottom; The reaction temperature in the first furnace is 800-1000°C, the reaction temperature in the second furnace is 600-900°C, and the reaction temperature in the third furnace is 500-750°C; preferably, the reaction temperature in the first furnace is 850-950°C, the reaction temperature in the second furnace is 650-850°C, and the reaction temperature in the third furnace is 550-700°C.

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