An experimental suspended mineral phase conversion device and its use method

Abstract

The present invention provides an experimental suspended mineral phase transformation device and a method for using the device, the device includes a feeding system, a reaction system, a heating and heat preservation system, a heating furnace, an air supply system, a gas composition analyzer, a temperature sensor and a pressure sensor, etc.; the feeding system is placed above the reaction system and is connected to the reaction system through a flange, the reaction system includes a particle settling chamber, a reaction chamber and a pressure drop chamber connected to the inner cavity from top to bottom, the particle settling chamber side wall is provided with a temperature measuring port, a pressure measuring port and an air outlet, an air distribution plate is provided between the reaction chamber and the pressure drop chamber, the pressure drop chamber side wall is provided with a pressure drop chamber pressure measuring port, an air inlet is provided at the bottom of the pressure drop chamber, the air inlet is connected to the air supply system, and the reaction chamber is placed in a heating furnace. The present invention can accurately control the mineral phase transformation process of the material in the gas-solid reaction process by controlling the temperature and pressure in the reaction chamber, and can carry out research on the mineral phase transformation control mechanism of minerals.

Description

Technical Field

[0001] The present invention belongs to the technical field of mineral processing equipment, and in particular relates to an experimental suspended mineral phase conversion device and a use method thereof. Background Art

[0002] my country boasts abundant iron ore reserves, but these resources are characterized by poor quality and fineness, with complex symbiotic relationships and fine grain sizes. Reserves of typical complex and refractory iron ores, such as oolitic hematite, siderite, limonite, and fine-grained ore, reach as high as 20 billion tons. Conventional beneficiation technologies struggle to achieve ideal economic and technical performance. Suspension magnetization roasting is an effective method for processing these ores. This technology aligns with national steel industry development goals, including energy conservation and emission reduction, technological transformation, elimination of outdated resources, and independent innovation. my country's utilization rate of refractory iron ores, such as hematite and limonite, is very low. Developing technologies for efficient utilization of these ores can reduce dependence on the international iron ore market. The widespread application of suspension roasting technology in the alumina industry, along with reliable theoretical and experimental data, scientific roasting process conditions, and rational process design, have all contributed to its successful application in the iron ore industry. Suspension magnetization roasting solves the challenges of magnetization roasting for refractory iron ores both domestically and internationally, representing a major breakthrough in refractory iron ore beneficiation technology. Its characteristics of low energy consumption, high efficiency and large processing capacity determine that this technology is highly competitive and has broad application prospects.

[0003] A small-scale suspension roasting device CN201910903016.6 is the first small-scale suspension continuous roasting device in China. It can simulate process production to a great extent and provide a good technical reference for the industrial debugging of the suspension roasting device. However, in the basic research work in the laboratory, the continuous roasting device cannot accurately judge the indicators of the test condition nodes. The existing roasting devices are mostly tubular vertical furnaces, and the furnace tubes are mostly quartz tubes. The mass transfer and heat transfer efficiency are very different from those of the steel furnace cavity, and it is difficult to accurately control the critical point of mineral phase transformation. Therefore, it is necessary to design an experimental suspended mineral phase transformation device to study the transformation process of the suspended mineral phase. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide an experimental suspended mineral phase conversion device and a method of use that are simple in structure, easy to adjust, and convenient to operate. The device has a high degree of automation, complete protection measures, and high safety, and can be used as an experimental suspended mineral phase conversion device.

[0005] The technical solution adopted by the present invention to solve its technical problems is: an experimental suspended mineral phase conversion device, including a feeding system, a reaction system, a heating furnace, and an air supply system; the feeding system is placed above the reaction system and connected to the reaction system through a flange, and the reaction system includes, from top to bottom, a particle settling chamber, a reaction chamber, and a pressure dividing chamber whose inner cavities are connected, and a temperature measuring port, a pressure measuring port, and an air outlet are provided on the side wall of the particle settling chamber, an air distribution plate is provided between the reaction chamber and the pressure dividing chamber, a pressure measuring port for the pressure dividing chamber is provided on the side wall of the pressure dividing chamber, and an air inlet is provided at the bottom of the pressure dividing chamber, and the air inlet is connected to the air supply system, and the reaction chamber is placed in the heating furnace.

[0006] Furthermore, the feeding system includes a feeding funnel, a feeding tube, and a double ball valve. The bottom of the funnel is connected to a feeding tube connected to the reaction system. A double ball valve is provided on the feeding tube, and the double ball valve includes valve I and valve II.

[0007] The feeding system further includes a quartz glass plate positioned at the bottom of the feeding tube, which passes through the quartz glass plate and connects to the reaction system. The feeding funnel, feeding tube, double-ball valve, and quartz glass plate are integrated into a single unit. The quartz glass plate and the reaction system are extrusion-sealed via a flange. The quartz glass plate serves as an observation window for directly observing the settling of material in the particle settling chamber and the surging state of material in the reaction chamber.

[0008] Furthermore, part of the particle settling chamber and part of the pressure dividing chamber are also placed in the heating furnace.

[0009] Furthermore, the temperature measuring port, pressure measuring port and air outlet are arranged on the side wall of the upper part of the particle sedimentation chamber, the temperature measuring port is connected to the temperature sensor, the pressure measuring port is connected to the first pressure sensor, and the air outlet is connected to the first flow sensor and the gas composition analyzer; the pressure measuring port of the pressure dividing chamber is arranged on the side wall of the lower part of the pressure dividing chamber, and the pressure measuring port of the pressure dividing chamber is connected to the second pressure sensor; a second flow sensor is provided on the connecting pipe between the air inlet and the air supply system.

[0010] Furthermore, the heating furnace has a ceramic fiber special-shaped furnace chamber, and the heating furnace body is a rotatable furnace body with a rotation angle of 0 to 180 degrees. The heating furnace adopts electric heating with an adjustable range of 0 to 1700°C and an accuracy of ±1°C.

[0011] Furthermore, the outer wall of the particle settling chamber gradually retracts from top to bottom, and the angle between the outer wall and the vertical direction is 5 to 15 degrees; the reaction chamber and the pressure drop chamber are straight cylindrical, and the air distribution plate is fixedly or detachably installed between the reaction chamber and the pressure drop chamber.

[0012] Furthermore, the air distribution plate is made of a porous high-temperature resistant dielectric material with a pore size of 0.15 to 1 mm.

[0013] Furthermore, the gas supply system is used to provide a single gas, or to mix 2 to 3 gases in any proportion and introduce them into the reaction system.

[0014] Furthermore, the mineral phase conversion device is suitable for experimental research on mineral phase conversion of iron minerals, rare earths, cyanide tailings, iron-aluminum symbiotic resources, stone coal and vanadium and other minerals.

[0015] The method for using the above-mentioned experimental suspended mineral phase conversion device includes the following steps:

[0016] Step 1: Heat the reaction system to a preset temperature and introduce safety gas (N2) into the reaction system through the air inlet to expel the air;

[0017] Step 2: Add the material to the feeding funnel, open valve I, wait for the material to completely pass through valve I, close valve I, open valve II, wait for the material to completely enter the reaction system, and close valve II;

[0018] Step 3: Ensure that valves I and II of the feeding system are closed, introduce reducing gas into the reaction system, and start timing;

[0019] Step 4: After the reaction time is up, stop introducing the reducing gas and introduce safety gas to evacuate the reducing gas;

[0020] Step 5: Open the connecting flange between the feeding system and the reaction system, remove the feeding system, and rotate the heating furnace body to take out the material;

[0021] Step 6: Reset the feeding system.

[0022] Compared with the prior art, the characteristics and beneficial effects of the present invention are:

[0023] (1) The device of the present invention has a high degree of automation, multiple protection measures such as over-temperature alarm, high control accuracy, safety and reliability, simple operation, and a single processing capacity of 30 to 200g;

[0024] (2) The feeding system in the device of the present invention is controlled by a double ball valve, which enables the addition of reactants into the counter-flow, thus avoiding the back-flushing effect of the counter-flow on the materials;

[0025] (3) The temperature of the device of the present invention can be adjusted over a wide range, up to 1700°C. The entire reaction system is made of 310S stainless steel, which has a high thermal conductivity.

[0026] (4) The suspended mineral phase transformation device of the present invention is based on magnetization roasting and can accurately control the mineral phase transformation process of materials during gas-solid reaction by controlling the temperature and pressure in the reaction chamber. It can be widely used in reducing atmosphere mineral phase transformation, oxidizing atmosphere mineral phase transformation, and neutral atmosphere mineral phase transformation of materials. The mineral phase transformation device of the present invention has a large temperature range (0-1700℃) and a wider range of applications. It can carry out research on the mineral phase transformation control mechanism of complex and difficult-to-select iron minerals, rare earth minerals, cyanide tailings, iron-aluminum symbiotic resources, stone coal and vanadium minerals.

[0027] (5) The device of the present invention can be equipped with various sensors according to the test requirements to facilitate real-time observation of the progress of the roasting reaction, such as temperature sensors, pressure sensors, flow sensors and gas composition analysis sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a structural diagram of the experimental suspended mineral phase conversion device of Example 1;

[0029] Figure 2 This is a top view of the experimental suspended mineral phase conversion device of Example 1;

[0030] Figure 3 This is a structural diagram of the air distribution plate of the device in Example 1;

[0031] Figure 4 This is the surface microstructure of the hematite raw mineral of Example 2;

[0032] Figure 5 This is the XRD analysis diagram of the sample of Example 3;

[0033] Figure 6 The XRD analysis diagrams of the raw ore and the products at each stage of the suspension magnetization roasting-magnetic separation process of Example 3 are as follows;

[0034] 1. Feeding funnel, 2. Valve I, 3. Valve II, 4. Pressure measuring port, 5. Temperature measuring port, 6. Air outlet, 7. Particle settling chamber, 8. Reaction chamber, 9. Heating furnace hearth, 10. Heating furnace, 11. Air distribution plate, 12. Pressure measuring port of pressure dividing chamber, 13. Pressure dividing chamber, 14. Air inlet, 15. Observation window. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] Example 1

[0037] like Figure 1 、 2As shown in Figure 3, the present invention provides an experimental suspended mineral phase conversion device, including a feeding system, a reaction system, a heating furnace 10, and an air supply system; the feeding system is placed above the reaction system and connected to the reaction system through a flange. The reaction system is made of 310S stainless steel, and includes, from top to bottom, a particle settling chamber 7, a reaction chamber 8, and a pressure dividing chamber 13 whose inner cavities are connected. A temperature measuring port 5, a pressure measuring port 4, and an air outlet 6 are provided on the side wall of the particle settling chamber. An air distribution plate 11 is provided between the reaction chamber and the pressure dividing chamber. A pressure measuring port 12 for the pressure dividing chamber is provided on the side wall of the pressure dividing chamber. An air inlet 14 is provided at the bottom of the pressure dividing chamber, and the air inlet is connected to the air supply system. The reaction chamber and part of the particle settling chamber and part of the pressure dividing chamber are placed in the furnace 9 of the heating furnace.

[0038] The feeding system includes a feeding funnel 1, a feeding tube, a double-ball valve, and a quartz glass plate. The bottom of the funnel is connected to a feeding tube connected to the reaction system. The feeding tube is provided with a double-ball valve. The double-ball valve includes valves I2 and II3, which are made of frosted quartz glass, are airtight, heat-resistant, and non-deformable. The quartz glass plate is provided at the bottom of the feeding tube, through which the feeding tube passes to connect to the reaction system. The feeding funnel, feeding tube, double-ball valve, and quartz glass plate are integrated. The quartz glass plate and the reaction system are extruded and sealed by a flange (using a flange seal + a high-temperature-resistant rubber gasket). The quartz glass plate serves as an observation window 15 for directly observing the sedimentation of the material in the particle settling chamber and the surging state of the material in the reaction chamber.

[0039] Among them, the temperature measuring port, pressure measuring port and air outlet are arranged on the side wall of the upper part of the particle sedimentation chamber, the temperature measuring port is connected to the temperature sensor, the pressure measuring port is connected to the first pressure sensor, which are respectively used to measure the temperature and air pressure above the particle sedimentation chamber, and the air outlet is connected to the first flow sensor and the gas composition analysis sensor; the pressure measuring port of the pressure dividing chamber is arranged on the side wall of the lower part of the pressure dividing chamber, and the pressure measuring port of the pressure dividing chamber is connected to the second pressure sensor to measure the air pressure in the pressure dividing chamber; a second flow sensor is provided on the connecting pipe between the air inlet and the air supply system.

[0040] Among them, the heating furnace has a ceramic fiber special-shaped furnace chamber, stepped sealing, and overall limit to ensure that the furnace chamber is not easy to deform or move. The heating furnace body is a rotatable furnace body with a rotation angle of 0 to 180°. The heating furnace adopts electric heating, and the heating element is a 1900 type silicon molybdenum rod with uniform temperature field, low energy consumption, adjustable range of 0 to 1700°C, and accuracy of ±1°C.

[0041] Among them, the outer wall of the particle settling chamber gradually retracts from top to bottom, and the angle between the outer wall and the vertical direction is 10°, which facilitates the sedimentation of materials into the reaction chamber; the reaction chamber and the pressure drop chamber are straight cylindrical, and the air distribution plate can be detachably installed between the reaction chamber and the pressure drop chamber.

[0042] Wherein, the air distribution plate is a porous high-temperature resistant asbestos mesh with a pore size of 0.15 to 1 mm.

[0043] The gas supply system can mix the two gases in any proportion and introduce them into the reaction system.

[0044] Example 2

[0045] The sample used in this embodiment is mixed magnetic concentrate, with a fineness of -0.074mm accounting for 87%. The chemical composition analysis results of the sample are shown in Table 1. The surface morphology characteristics are as follows: Figure 4 As shown;

[0046] Table 1 Chemical composition analysis of ore samples (mass fraction, %)

[0047]

[0048]

[0049] It can be seen from Table 1 that the iron grade of the sample is 35.6%, the main impurity is silicon dioxide with a content of 38.70%, and the harmful impurities are P and S with contents of 0.02% and 0.03% respectively.

[0050] The method for using the experimental suspended mineral phase conversion device based on Example 1 includes the following steps:

[0051] Step 1: First, start the heating furnace to heat the reaction system to a preset temperature of 560°C. Then, open the gas outlet 6. The gas supply system allows nitrogen gas to enter the pressure drop chamber 13 from the gas inlet 14. The gas in the pressure drop chamber 13 enters the reaction chamber 8 through the air distribution plate 11, thereby evacuating the reaction chamber 8.

[0052] Step 2: After the air is exhausted, open valve I2 and add 50g of the reaction material into the addition funnel 1. After the material has completely passed through valve I2, close valve I and open valve II3. After the material has completely passed through valve II, close valve II. The reaction material enters the sedimentation chamber and finally enters the reaction chamber.

[0053] Step 3: By controlling the gas supply system, 30% concentration of CO (CO 300ml / min, N2 700ml / min) enters the pressure chamber 13 from the air inlet 14, and the gas in the pressure chamber 13 enters the reaction chamber 8 through the air distribution plate 11, and the timing starts; the gas forms multiple airflows after passing through the air distribution plate, so that the material in the reaction chamber is in a suspended state, and a gas-solid reduction reaction occurs. Through the observation window of the quartz glass plate, the sedimentation phenomenon of the material in the particle sedimentation chamber and the surging state of the material in the reaction chamber can be observed.

[0054] Step 4: After 15 minutes of reaction, the CO concentration is adjusted to 0 by controlling the gas supply system, while the total gas volume remains unchanged. The gas in the reaction chamber is evacuated, and then the connecting flange between the feeding system and the reaction system is opened. The feeding system is removed, and the reaction system is rotated 120° to remove the material.

[0055] Step 5: Restore the reaction system to its original position, install the feeding system, close the gas supply system and all gas circuit switches, turn off the power, and the reaction is completed.

[0056] The chemical composition analysis results of the samples magnetically separated after calcination by the device of the present invention are shown in Table 2;

[0057] Table 2 Chemical composition analysis of samples after calcination

[0058]

[0059] As shown in Table 2, the iron grade of the concentrate after roasting is 28.7% higher than that before roasting, and the recovery rate is increased by 18.26%. It can be used as a high-quality raw material for ironmaking.

[0060] Example 3

[0061] The raw material used in the experiment is a high iron bauxite from Indonesia. The chemical multi-element analysis results of the raw ore are shown in Table 3. The mineral composition of the high iron bauxite sample was analyzed by X-ray diffraction (XRD). The results are as follows: Figure 5 shown.

[0062] Table 3 Chemical multi-element analysis results of raw ore

[0063]

[0064]

[0065] Based on the experimental suspended mineral phase conversion device of Example 1 and the usage method of Example 2, the roasting conditions are different from those of Example 2: the reduction roasting temperature is 600°C, the total gas flow rate is 500mL / min, the roasting time is 20min, and the CO concentration is 20%. A suspended magnetization roasting test is carried out, and weak magnetic separation is carried out under the condition of a magnetic field intensity of 133.6kA / min. An aluminum concentrate with an alumina content of 68.55% and an iron removal rate of 65.63% can be obtained.

[0066] XRD was used to analyze the physical phases of the raw ore, roasted product and selected product. The results are as follows: Figure 6 As shown. Figure 6The roasted product is primarily composed of crystalline magnetite and quartz. The gibbsite phase in the original ore disappears, leaving amorphous Al2O3 in the roasted product. The magnetic concentrate is primarily magnetite, while the aluminum concentrate is primarily amorphous Al2O3 with a certain amount of quartz. XRD analysis indicates that the roasting-magnetic separation process effectively separates aluminum and iron minerals, significantly reducing the iron content in the aluminum concentrate.

[0067] The above technical solution illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes and modifications made to the above technical solution based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. An experimental suspended mineral phase conversion device, characterized by: It includes a feeding system, a reaction system, a heating furnace, and an air supply system; the feeding system is placed above the reaction system and connected to the reaction system through a flange; the reaction system includes, from top to bottom, a particle settling chamber, a reaction chamber, and a pressure drop chamber with interconnected inner cavities; a temperature measuring port, a pressure measuring port, and an air outlet are provided on the side wall of the particle settling chamber; an air distribution plate is provided between the reaction chamber and the pressure drop chamber; a pressure measuring port for the pressure drop chamber is provided on the side wall of the pressure drop chamber; an air inlet is provided at the bottom of the pressure drop chamber; the air inlet is connected to the air supply system; and the reaction chamber is placed in the heating furnace; The feeding system includes a feeding funnel, a feeding tube, and a double ball valve. The bottom of the funnel is connected to a feeding tube connected to the reaction system. The feeding tube is provided with a double ball valve, which includes valve I and valve II. The gas supply system is used to provide a single gas, or to mix 2 to 3 gases in any proportion and introduce them into the reaction system.

2. The experimental suspended mineral phase conversion device according to claim 1, characterized in that: The feeding system also includes a quartz glass plate, which is arranged at the bottom of the feeding tube. The feeding tube passes through the quartz glass plate and is connected to the reaction system. The feeding funnel, feeding tube, double ball valve, and quartz glass plate are integrated into one design; the quartz glass plate and the reaction system are squeezed and sealed by a flange.

3. The experimental suspended mineral phase conversion device according to claim 1, characterized in that: The temperature measuring port, pressure measuring port and air outlet are arranged on the side wall of the upper part of the particle sedimentation chamber, the temperature measuring port is connected to the temperature sensor, the pressure measuring port is connected to the first pressure sensor, and the air outlet is connected to the first flow sensor and the gas composition analysis sensor; the pressure measuring port of the pressure dividing chamber is arranged on the side wall of the lower part of the pressure dividing chamber, and the pressure measuring port of the pressure dividing chamber is connected to the second pressure sensor; a second flow sensor is provided on the connecting pipe between the air inlet and the air supply system.

4. The experimental suspended mineral phase conversion device according to claim 1, characterized in that: The heating furnace has a ceramic fiber special-shaped furnace chamber, and the heating furnace body is a rotatable furnace body with a rotation angle of 0~180°. The heating furnace adopts electric heating, and the adjustable range is 0~1700℃ with an accuracy of ±1℃; part of the particle sedimentation chamber and part of the pressure dividing chamber are also placed in the heating furnace.

5. The experimental suspended mineral phase conversion device according to claim 1, characterized in that: The outer wall of the particle settling chamber gradually retracts from top to bottom, and the angle between the outer wall and the vertical direction is 5~15°; the reaction chamber and the pressure drop chamber are straight cylindrical, and the air distribution plate is fixedly or detachably installed between the reaction chamber and the pressure drop chamber.

6. The experimental suspended mineral phase conversion device according to claim 1, characterized in that: The air distribution plate is made of a porous high-temperature resistant medium material with a pore size of 0.15-1 mm.

7. The experimental suspended mineral phase conversion device according to claim 1, characterized in that: The mineral phase conversion device is suitable for mineral phase conversion experiments on iron minerals, rare earths, cyanide tailings, iron-aluminum symbiotic resources, and stone coal-vanadium minerals.

8. The method for using the experimental suspended mineral phase conversion device according to claim 1, characterized in that: The following steps are involved: Step 1: Heat the reaction system to the preset temperature, and introduce safety gas into the reaction system through the air inlet to expel the air; Step 2: Add the material to the feeding funnel, open valve I, wait for the material to completely pass through valve I, close valve I, open valve II, wait for the material to completely enter the reaction system, and close valve II; Step 3: Ensure that valves I and II of the feeding system are closed, introduce reducing gas into the reaction system, and start timing; Step 4: After the reaction time is up, stop introducing the reducing gas and introduce safety gas to evacuate the reducing gas; Step 5: Open the connecting flange between the feeding system and the reaction system, remove the feeding system, and rotate the heating furnace body to take out the material; Step 6: Reset the feeding system.

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