An integrated device and system for magnetic separation and roasting of iron ore and method of use

Abstract

An integrated device and system for magnetic separation and roasting of iron ore and a method for using the same, comprising an outer shell, a partition, magnetic poles, and an inner tube. The partition is disposed inside the outer shell and divides the interior of the outer shell into an upper chamber and a lower chamber. The magnetic poles and the inner tube are disposed in the lower chamber. The upper chamber as a whole constitutes a fluidized roasting zone, and an oxidizing gas inlet is provided on the side wall of the upper chamber. The inner tube is vertically disposed in the lower chamber. A material and gas inlet is provided at the bottom of the inner tube, and a magnetic material outlet and a non-magnetic material outlet are provided on both sides of the upper side wall of the inner tube. The magnetic poles are located outside the inner tube and opposite to the magnetic material outlet. The present invention arranges the magnetic separation and roasting steps of iron ore in the same device, which can effectively shorten the process flow, save energy consumption, and improve the overall efficiency of the process. Furthermore, through the negative pressure exhaust unit and the multi-stage series magnetic separation structure, the purity of the magnetic material is effectively improved, thereby ensuring the quality of the final product.

Description

Technical Field

[0001] The present invention relates to a magnetic separation and roasting integrated device and system and a use method, and in particular to an iron ore magnetic separation and roasting integrated device and system and a use method, belonging to the technical field of steel smelting. Background Art

[0002] Pyrrhotite Fe 1-x S (0<x<0.223) is an iron sulfide mineral, which is abundant in nature and mostly exists in associated forms. Its surface is dark bronze yellow, and its magnetic strength varies. The strength of its magnetic force depends on the number of iron atom vacancies in its internal structure. It can generally be recovered by magnetic separation. The composition of pyrrhotite is relatively complex, and it is usually mixed with magnetic materials (such as iron, copper and nickel). There are almost no single crystal system pyrrhotite minerals in nature, and more than 70% are mixed crystal systems. Therefore, it is difficult to separate them using a single separation method. Due to some Fe 2+ Fe 3+ Instead, in order to maintain the balance of electricity prices, 2+ Vacancies appear at different positions, forming an empty solid solution. Due to the varying arrangement of lattice vacancies, pyrrhotite forms a variety of structures, with hexagonal HPO and monoclinic MPO being two common types. Due to defects in its crystal structure, pyrrhotite is more susceptible to oxidation than other sulfide minerals in the presence of oxidants such as oxygen or ferric iron ions, hindering flotation. Currently, wet magnetic separation is the primary method for enriching pyrrhotite. The resulting pyrrhotite concentrate is filtered, dried, and then roasted in a fluidized bed furnace for sulfuric acid production. Sulfate slag is produced as a byproduct.

[0003] Fluidization refers to the process of solid particles becoming fluidized by a fluid medium. This process imparts liquid-like properties to the material. As early as the 1950s and 1960s, researchers both domestically and internationally focused on fluidized roasting technology, with research conducted in the United States, the United Kingdom, Canada, Italy, Russia, and other countries. However, in recent years, the development of complex and difficult-to-process iron ores has largely ceased abroad, and few reports on fluidized roasting have been published.

[0004] Many domestic research institutes have conducted extensive research on fluidized roasting equipment and technology. The Changsha Research Institute of Mining and Metallurgy has conducted research on fluidized magnetic roasting of dozens of iron ores. Using a complete set of flash magnetic roasting technology and equipment, a mixed ore with a raw grade of 32.52% iron ferromagnetic iron was commercially produced, achieving an iron concentrate grade of 57.52% and an iron recovery rate of 90.24%. This has opened up a new path for the development and utilization of complex and difficult-to-process iron ores in my country. The Institute of Process Engineering of the Chinese Academy of Sciences uses a fluidized bed reactor as a magnetic roasting device. Results show that, using magnetic roasting and magnetic separation for untreated ore fines, the iron grade in the concentrate can be increased to approximately 55%, with an iron recovery rate of less than 70%. For pretreated ore fines, the iron grade in the concentrate can be increased to 60.18%, with an iron recovery rate of 85.91%. The pretreated ore fines develop a porous and loose structure, allowing reducing gases to easily penetrate the iron ore particles, promoting the formation of Fe₃O₄ and improving magnetic separation performance.

[0005] The chemical formula of pyrrhotite is Fe 1-x S (0 < x < 0.223), has both electrical conductivity and magnetism. Currently, sulfuric acid is primarily produced using wet magnetic separation followed by high-temperature oxidative roasting, with sulfate slag as a byproduct. However, wet magnetic separation requires a large amount of water, and the resulting magnetically separated concentrate requires filtration and drying before it can be qualified as raw material for the high-temperature roasting process. This long process, high energy consumption, and significant investment significantly hinder the efficient utilization of pyrrhotite resources. Furthermore, the existing magnetization roasting process consists of two separate steps, resulting in a complex process flow and the need for transport. Summary of the Invention

[0006] In view of the problems in the existing technology that wet magnetic separation uses a large amount of water, has a long process, high energy consumption, and a large investment, and the magnetization roasting process is complex and has a transportation process, the present invention proposes an integrated device and system for magnetic separation and roasting of iron ore, which integrates magnetization and roasting in the same device, first performs dry magnetic separation and then roasting, without an intermediate transportation process, and only needs to control the air volume and roasting temperature to complete the entire process of magnetization roasting, shortening the process flow, saving energy consumption, and improving the overall efficiency of the process.

[0007] According to a first embodiment of the present invention, an integrated device for magnetic separation and roasting of iron ore is provided.

[0008] An integrated iron ore magnetic separation and roasting device comprises an outer shell, a partition, magnetic poles, and an inner tube. The partition is disposed within the outer shell and divides the interior of the outer shell into an upper chamber and a lower chamber. The magnetic poles and inner tube are disposed within the lower chamber. The upper chamber as a whole constitutes a fluidized roasting zone. An oxidizing gas inlet is provided on the sidewall of the upper chamber.

[0009] The inner tube is vertically positioned within the lower chamber, with its upper end connected to the baffle. Material and gas inlets are located at the bottom of the inner tube, while magnetic and non-magnetic material outlets are located on either side of the upper side of the inner tube. The magnetic poles are located on the outside of the inner tube, facing the magnetic material outlets.

[0010] The interior of the inner tube entirely constitutes the drying and magnetic separation zone. A calcination zone feed port is defined on the partition plate near the magnetic material outlet. Below the calcination zone feed port is a transition zone, with a secondary gas inlet located at the bottom of the transition zone. The magnetic material outlet is connected to the calcination zone feed port through the transition zone. Both the drying and magnetic separation zone and the fluidized calcination zone are equipped with heating mechanisms.

[0011] Preferably, the non-magnetic material outlet and the magnetic material outlet are arranged opposite to each other.

[0012] Preferably, a negative pressure exhaust unit is connected to the outside of the non-magnetic material outlet.

[0013] Preferably, a sieve plate is provided at the magnetic material outlet and / or the non-magnetic material outlet and / or the feed inlet of the roasting zone.

[0014] Preferably, the sieve plate has a sieve hole diameter of 1 to 5 mm, preferably 1 to 3 mm.

[0015] Preferably, the device further comprises a non-magnetic material discharge pipe, which is arranged outside the non-magnetic material outlet, with one end of the non-magnetic material discharge pipe being connected to the non-magnetic material outlet and the other end being connected to an external negative pressure exhaust unit.

[0016] Preferably, the device further includes a magnetic material conveying pipe. The magnetic material conveying pipe is disposed outside the magnetic material outlet, with one end connected to the magnetic material outlet and the other end connected to the transition zone. The magnetic pole is disposed on the side wall of the magnetic material conveying pipe opposite the magnetic material outlet. Preferably, the horizontal distance between the magnetic pole and the inner tube sidewall is 0.2 to 1.5 meters, more preferably 0.5 to 1 meter.

[0017] Preferably, the non-magnetic material discharge pipe and / or the magnetic material conveying pipe are both vertical or inclined channels from top to bottom.

[0018] Preferably, the system includes m stages of magnetic material conveying pipes connected in series, where m ranges from 2 to 6. The m stages of magnetic material conveying pipes are connected in series in the following manner: in a first-stage magnetic material conveying pipe, a secondary magnetic separation inlet is provided on the side wall of the pipe body on the same side below the magnetic pole, the secondary magnetic separation inlet is connected to the second-stage magnetic material conveying pipe, a secondary magnetic pole is provided on the side wall of the second-stage magnetic material conveying pipe, and the secondary magnetic pole is arranged opposite the secondary magnetic separation inlet, and so on.

[0019] Preferably, the device comprises n stages of magnetic poles and inner tubes connected in series, with n ranging from 2 to 6. The n stages of magnetic poles and inner tubes are connected in series in such a manner that the magnetic material outlet of the first inner tube is connected to the material and gas inlet of the second inner tube, and so on.

[0020] Preferably, the device further comprises an oxidizing gas nozzle, the oxidizing gas nozzle being disposed at the oxidizing gas inlet, and the oxidizing gas nozzle being inclined such that the gas outlet end is higher than the gas inlet end. Preferably, the angle between the oxidizing gas nozzle and the horizontal plane is 30 to 75 degrees, more preferably 40 to 60 degrees.

[0021] Preferably, a gas flow monitoring unit is provided at the oxidizing gas inlet.

[0022] Preferably, the magnetic pole is an electromagnet.

[0023] Preferably, a magnetic pole cleaning unit is further provided at the magnetic pole.

[0024] Preferably, a temperature monitoring unit is provided on the side wall of the fluidized roasting zone.

[0025] Preferably, a gas flow monitoring unit is provided at the material and gas inlet.

[0026] Preferably, a gas flow monitoring unit is provided at the secondary gas inlet.

[0027] According to a second embodiment of the present invention, an integrated system for magnetic separation and roasting of iron ore is provided.

[0028] An integrated iron ore magnetic separation and roasting system, comprising an integrated iron ore magnetic separation and roasting device, a grinding device, an inert gas source, an oxidizing gas source, and a non-magnetic material collection device. The discharge port of the grinding device is connected to the material and gas inlets of the integrated iron ore roasting device via a material conveying pipeline, and the pipe body of the material conveying pipeline is provided with a first gas pipeline connected to the inert gas source. The inert gas source is connected to the gas inlet of the integrated iron ore roasting device via a second gas pipeline. The oxidizing gas source is connected to the oxidizing gas inlet of the integrated iron ore roasting device via a third gas pipeline. The non-magnetic material collection device is arranged below the non-magnetic material outlet 8.

[0029] Preferably, a screening device is provided at the discharge port of the grinding device, wherein the diameter of the sieve hole of the screening device is 1 to 5 mm, preferably 1 to 3 mm.

[0030] According to a third embodiment of the present invention, an integrated method for magnetic separation and roasting of iron ore is provided.

[0031] An integrated method for magnetic separation and roasting of iron ore, comprising the following steps:

[0032] 1) After grinding and screening, the iron ore enters the drying magnetic separation area from the material and gas inlet under the action of inert airflow and moves upward. The magnetic material is attracted by the magnetic pole and enters the transition zone from the magnetic material outlet, and the non-magnetic material is discharged from the non-magnetic material outlet.

[0033] 2) Inert gas is introduced into the transition zone through the second gas pipeline, and the magnetic material enters the fluidized calcination zone through the calcination zone inlet under the action of the inert gas flow.

[0034] 3) An oxidizing gas is introduced into the fluidized bed roasting zone, and the magnetic material reacts at 500-1000°C for 0.1-1h to complete the magnetic separation roasting.

[0035] Preferably, the magnetic field strength of the magnetic pole is 0.05-1.5T, preferably 0.1-1.0T.

[0036] Preferably, the inert gas is nitrogen, and the flow rate of the inert gas is 0.1-2 m / s.

[0037] Preferably, the oxidizing gas is oxygen or air, preferably air, and the flow rate of the oxidizing gas is 0.3 to 3 m / s.

[0038] Preferably, the temperature in the drying magnetic separation zone is 0-200°C, preferably 50-100°C.

[0039] Preferably, the heating method in the fluidized roasting zone and / or the drying magnetic separation zone is electric heating.

[0040] The present invention provides an integrated device for magnetic separation and roasting of iron ore. A partition, an inner tube, and magnetic poles are disposed within an outer shell. A mixed material (i.e., iron ore particles) enters the inner tube from the material and gas inlet at the bottom of the inner tube under the action of an airflow, and moves upward within the inner tube under the action of the airflow. A magnetic material outlet is provided on the sidewall of the inner tube, and magnetic poles are disposed on the outer side of the magnetic material outlet. The magnetic material in the mixed material is attracted by the magnetic poles and discharged from the inner tube through the magnetic material outlet, completing dry magnetic separation. The magnetic material is then fed into a roasting zone, and an oxidizing gas is introduced into the fluidized roasting zone for roasting, achieving the process effect of integrated magnetic roasting, which can effectively shorten the process, reduce energy consumption, and minimize investment.

[0041] In the present invention, a non-magnetic material outlet is opened on the other side of the top of the inner tube side wall. The non-magnetic material is discharged through the non-magnetic material outlet under the drive of the primary wind and collected to form tailings. Preferably, a sieve plate is provided at the magnetic material outlet and / or the non-magnetic material outlet and / or the feed inlet of the roasting zone to screen the magnetic material entering the roasting zone and the tailings discharged through the non-magnetic material outlet, so as to facilitate the subsequent process. The magnetic material and tailings with excessive particle size can be re-ground and then passed into the device again from the material and gas inlet. Preferably, a non-magnetic material discharge pipe and / or a magnetic material conveying pipe are provided outside the non-magnetic material outlet to facilitate the discharge and collection of materials. In addition, the distance between the magnetic pole and the side wall of the inner tube (i.e., the width of the magnetic material conveying pipe) is 0.2 to 1.5 m to ensure the full separation of the magnetic material.

[0042] In the present invention, an oxidizing gas inlet is provided on the side wall of the upper chamber, and oxidizing gas is introduced into the fluidized roasting zone. Preferably, a gas flow monitoring unit is provided to monitor and control the flow rate of the primary air and / or secondary air and / or oxidizing gas, and a temperature monitoring unit is provided in the fluidized roasting zone so that the magnetized roasting process reaches the optimal process parameters. Preferably, an inclined oxidizing gas nozzle is provided at the oxidizing gas inlet so that the air flow is ejected upward, which facilitates the fluidized roasting process. In the roasting zone, the air flow velocity is adjusted to control the material to be suspended in the set temperature range and position range, and a high-temperature oxidation reaction (Fe 1-x The SO2 gas generated is collected to make sulfuric acid. The remaining material is sulfuric acid slag, which is collected for comprehensive utilization.

[0043] In the present invention, a negative pressure exhaust unit is connected to the outside of the non-magnetic material outlet to reduce the airflow flowing to the magnetic material outlet, and reduce the probability of non-magnetic material being discharged from the magnetic material outlet under the influence of the airflow. Furthermore, it is possible to set multiple stages of magnetic poles and inner tubes in series, or to set multiple stages of magnetic material conveying pipes. Since there is only one stage of magnetic separation, there may be a situation where the airflow passes through the magnetic material outlet and is discharged from the inner tube, thereby taking out some non-magnetic materials, which can easily lead to a decrease in the purity of the roasting product. After setting multiple stages of magnetic poles and inner tubes in series, or setting multiple stages of magnetic material conveying pipes, the material entering the magnetic material conveying pipe can be further magnetically separated to improve the purity of the final product.

[0044] In the present invention, the magnetic pole is preferably an electromagnet. When the properties of the raw materials change or the requirements of the subsequent process for the materials change, the magnetic field strength can be changed to meet production requirements, simplify process steps, and improve production efficiency.

[0045] The present invention also provides an integrated iron ore magnetic separation and roasting system. The iron ore raw material is ground and then transported to the iron ore magnetic roasting integrated device. Preferably, a screening device is also provided to ensure that the iron ore meets the particle size requirements of dry magnetic separation and fluidized roasting.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. The present invention provides an integrated device and system for magnetic separation and roasting of iron ore, which sets the magnetic separation and roasting steps of iron ore in the same device, which can effectively shorten the process flow, save energy consumption, and improve the overall efficiency of the process. The negative pressure exhaust unit and the multi-stage series magnetic separation structure effectively improve the purity of the magnetic material and ensure the quality of the final product.

[0048] 2. The present invention provides an integrated device and system for magnetic separation and roasting of iron ore, which is equipped with multiple sieve plates to ensure that the particle size of the iron ore meets the roasting requirements. In addition, the magnetic poles are set as electromagnets to meet the needs under different working conditions, effectively expanding the scope of application of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a schematic diagram of the first structure of an integrated device for magnetic separation and roasting of iron ore provided by the present invention.

[0050] Figure 2 This is a second structural schematic diagram of an iron ore magnetic separation and roasting integrated device provided by the present invention.

[0051] Figure 3 This is a schematic diagram of the third structure of an integrated device for magnetic separation and roasting of iron ore provided by the present invention.

[0052] Figure markings: 1: outer shell; 2: partition; 3: magnetic pole; 4: inner tube; 5: oxidizing gas inlet; 6: material and gas inlet; 7: magnetic material outlet; 8: non-magnetic material outlet; 9: roasting zone feed inlet; 10: secondary gas inlet; 11: sieve plate; 12: non-magnetic material discharge pipe; 13: magnetic material conveying pipe; 14: oxidizing gas nozzle. DETAILED DESCRIPTION

[0053] The technical solutions of the present invention are illustrated below with examples, and the scope of protection requested by the present invention includes but is not limited to the following embodiments.

[0054] According to a first embodiment of the present invention, an integrated device for magnetic separation and roasting of iron ore is provided.

[0055] An integrated device for magnetic separation and roasting of iron ore comprises an outer shell 1, a partition 2, magnetic poles 3, and an inner tube 4. The partition 2 is disposed within the outer shell 1 and divides the interior of the outer shell 1 into an upper chamber and a lower chamber. The magnetic poles 3 and inner tube 4 are disposed within the lower chamber. The upper chamber as a whole constitutes a fluidized roasting zone A. An oxidizing gas inlet 5 is provided on the sidewall of the upper chamber.

[0056] The inner tube 4 is vertically disposed within the lower chamber, and the upper end of the inner tube 4 is connected to the partition 2. A material and gas inlet 6 is provided at the bottom of the inner tube 4, and a magnetic material outlet 7 and a non-magnetic material outlet 8 are provided on both sides of the upper sidewall of the inner tube 4. The magnetic pole 3 is located outside the inner tube 4 and opposite the magnetic material outlet 7.

[0057] The interior of the inner tube 4 constitutes the drying magnetic separation zone B. A calcination zone feed port 9 is formed on the plate of the partition 2 near the magnetic material outlet 7. Below the calcination zone feed port 9 is a transition zone C, with a secondary gas inlet 10 at the bottom of the transition zone C. The magnetic material outlet 7 is connected to the calcination zone feed port 9 through the transition zone C. Both the drying magnetic separation zone B and the fluidized calcination zone A are equipped with heating mechanisms.

[0058] Preferably, the non-magnetic material outlet 8 and the magnetic material outlet 7 are arranged opposite to each other.

[0059] Preferably, a negative pressure exhaust unit is connected to the outside of the non-magnetic material outlet 8.

[0060] Preferably, a sieve plate 11 is provided at the magnetic material outlet 7 and / or the non-magnetic material outlet 8 and / or the roasting zone feed inlet 9.

[0061] Preferably, the sieve plate 11 has a sieve hole diameter of 1 to 5 mm, preferably 1 to 3 mm.

[0062] Preferably, the device further comprises a non-magnetic material discharge pipe 12. The non-magnetic material discharge pipe 12 is arranged outside the non-magnetic material outlet 8, one end of the non-magnetic material discharge pipe 12 is connected to the non-magnetic material outlet, and the other end is connected to the external negative pressure exhaust unit.

[0063] Preferably, the device further includes a magnetic material conveying pipe 13. Said magnetic material conveying pipe 13 is disposed outside the magnetic material outlet 7, with one end of said magnetic material conveying pipe 13 communicating with the magnetic material outlet 7 and the other end communicating with the transition zone C. Said magnetic pole 3 is disposed on the side wall of said magnetic material conveying pipe 13 opposite the magnetic material outlet 7. Preferably, the horizontal distance between said magnetic pole 3 and the side wall of said inner tube 4 is 0.2 to 1.5 m, more preferably 0.5 to 1 m.

[0064] Preferably, the non-magnetic material discharge pipe 12 and / or the magnetic material conveying pipe 13 are both vertical or inclined channels from top to bottom.

[0065] Preferably, the system includes m stages of magnetic material conveying pipes 13 connected in series, where m ranges from 2 to 6. The m stages of magnetic material conveying pipes 13 are connected in series in the following manner: in a first-stage magnetic material conveying pipe 13, a second magnetic separation inlet is provided on the side wall of the pipe body below the magnetic pole 3 on the same side as the pipe body, the second magnetic separation inlet is connected to the second-stage magnetic material conveying pipe 13, a second magnetic pole 3 is provided on the side wall of the second-stage magnetic material conveying pipe 13, and the second magnetic pole 3 is arranged opposite the second magnetic separation inlet, and so on.

[0066] Preferably, the device comprises n stages of magnetic poles 3 and inner tubes 4 connected in series, where n is 2 to 6. The n stages of magnetic poles and inner tubes 4 are connected in series in such a manner that the magnetic material outlet 7 of the first stage inner tube 4 is connected to the material and gas inlet 6 of the second stage inner tube 4, and so on.

[0067] Preferably, the apparatus further comprises an oxidizing gas nozzle 14, which is disposed at the oxidizing gas inlet 5 and is inclined such that the gas outlet end of the oxidizing gas nozzle 14 is higher than the gas inlet end. Preferably, the angle between the oxidizing gas nozzle and the horizontal plane is 30 to 75 degrees, more preferably 40 to 60 degrees.

[0068] Preferably, a gas flow monitoring unit is provided at the oxidizing gas inlet 5 .

[0069] Preferably, the magnetic pole 3 is an electromagnet.

[0070] Preferably, a magnetic pole cleaning unit is further provided at the magnetic pole 3 .

[0071] Preferably, a temperature monitoring unit is provided on the side wall of the fluidized roasting zone A.

[0072] Preferably, a gas flow monitoring unit is provided at the material and gas inlet 6 .

[0073] Preferably, a gas flow monitoring unit is provided at the secondary gas inlet 10 .

[0074] According to a second embodiment of the present invention, an integrated system for magnetic separation and roasting of iron ore is provided.

[0075] An integrated iron ore magnetic separation and roasting system, comprising an integrated iron ore magnetic separation and roasting device, a grinding device, an inert gas source, an oxidizing gas source, and a non-magnetic material collection device. The discharge port of the grinding device is connected to the material and gas inlets of the integrated iron ore roasting device via a material conveying pipeline, and the pipe body of the material conveying pipeline is provided with a first gas pipeline connected to the inert gas source. The inert gas source is connected to the gas inlet of the integrated iron ore roasting device via a second gas pipeline. The oxidizing gas source is connected to the oxidizing gas inlet of the integrated iron ore roasting device via a third gas pipeline. The non-magnetic material collection device is arranged below the non-magnetic material outlet 8.

[0076] Preferably, a screening device is provided at the discharge port of the grinding device, wherein the diameter of the sieve hole of the screening device is 1 to 5 mm, preferably 1 to 3 mm.

[0077] According to a third embodiment of the present invention, an integrated method for magnetic separation and roasting of iron ore is provided.

[0078] An integrated method for magnetic separation and roasting of iron ore, comprising the following steps:

[0079] 1) After grinding and screening, the iron ore enters the drying magnetic separation area from the material and gas inlet under the action of inert airflow and moves upward. The magnetic material is attracted by the magnetic pole and enters the transition zone from the magnetic material outlet, and the non-magnetic material is discharged from the non-magnetic material outlet.

[0080] 2) Inert gas is introduced into the transition zone through the second gas pipeline, and the magnetic material enters the fluidized calcination zone through the calcination zone inlet under the action of the inert gas flow.

[0081] 3) An oxidizing gas is introduced into the fluidized bed roasting zone, and the magnetic material reacts at 500-1000°C for 0.1-1h to complete the magnetic separation roasting.

[0082] Preferably, the magnetic field strength of the magnetic pole is 0.05-1.5T, preferably 0.1-1.0T.

[0083] Preferably, the inert gas is nitrogen, and the flow rate of the inert gas is 0.1-2 m / s.

[0084] Preferably, the oxidizing gas is oxygen or air, preferably air, and the flow rate of the oxidizing gas is 0.3 to 3 m / s.

[0085] Preferably, the temperature in the drying magnetic separation zone is 0-200°C, preferably 50-100°C.

[0086] Preferably, the heating method in the fluidized roasting zone and / or the drying magnetic separation zone is electric heating.

[0087] Example 1

[0088] An integrated device for magnetic separation and roasting of iron ore comprises an outer shell 1, a partition 2, magnetic poles 3, and an inner tube 4. The partition 2 is disposed within the outer shell 1 and divides the interior of the outer shell 1 into an upper chamber and a lower chamber. The magnetic poles 3 and inner tube 4 are disposed within the lower chamber. The upper chamber as a whole constitutes a fluidized roasting zone A. An oxidizing gas inlet 5 is provided on the sidewall of the upper chamber.

[0089] The inner tube 4 is vertically disposed within the lower chamber, and the upper end of the inner tube 4 is connected to the partition 2. A material and gas inlet 6 is provided at the bottom of the inner tube 4, and a magnetic material outlet 7 and a non-magnetic material outlet 8 are provided on both sides of the upper sidewall of the inner tube 4. The magnetic pole 3 is located outside the inner tube 4 and opposite the magnetic material outlet 7.

[0090] The interior of the inner tube 4 constitutes the drying magnetic separation zone B. A calcination zone feed port 9 is formed on the plate of the partition 2 near the magnetic material outlet 7. Below the calcination zone feed port 9 is a transition zone C, with a secondary gas inlet 10 at the bottom of the transition zone C. The magnetic material outlet 7 is connected to the calcination zone feed port 9 through the transition zone C. Both the drying magnetic separation zone B and the fluidized calcination zone A are equipped with heating mechanisms.

[0091] Example 2

[0092] Example 1 is repeated, except that the non-magnetic material outlet 8 and the magnetic material outlet 7 are arranged opposite to each other.

[0093] The outside of the non-magnetic material outlet 8 is connected to a negative pressure exhaust unit.

[0094] The magnetic material outlet 7 , the non-magnetic material outlet 8 and the roasting zone feed inlet 9 are provided with sieve plates 11 .

[0095] The sieve plate 11 has a sieve hole diameter of 3 mm.

[0096] Example 3

[0097] Repeat Example 2, except that the device further includes a non-magnetic material discharge pipe 12. The non-magnetic material discharge pipe 12 is arranged outside the non-magnetic material outlet 8, one end of the non-magnetic material discharge pipe 12 is connected to the non-magnetic material outlet, and the other end is connected to the external negative pressure exhaust unit.

[0098] Example 4

[0099] Example 3 was repeated, except that the device also included a magnetic material conveying pipe 13. The magnetic material conveying pipe 13 was located outside the magnetic material outlet 7. One end of the magnetic material conveying pipe 13 was connected to the magnetic material outlet 7, and the other end was connected to the transition zone C. The magnetic pole 3 was located on the side wall of the magnetic material conveying pipe 13 opposite the magnetic material outlet 7. The horizontal distance between the magnetic pole 3 and the side wall of the inner tube 4 was 0.8 m.

[0100] The non-magnetic material discharge pipe 12 and the magnetic material conveying pipe 13 are both vertical channels from top to bottom.

[0101] Example 5

[0102] like Figure 2 As shown, Example 4 is repeated, except that the system includes three stages of magnetic material conveying pipes 13 connected in series. The three stages of magnetic material conveying pipes 13 are connected in series as follows: in the first stage of the magnetic material conveying pipe 13, a secondary magnetic separation inlet is provided on the side wall of the pipe body below the magnetic pole 3 on the same side, and the secondary magnetic separation inlet is connected to the second stage of the magnetic material conveying pipe 13. A secondary magnetic pole 3 is provided on the side wall of the second stage of the magnetic material conveying pipe 13, and the secondary magnetic pole 3 is arranged opposite the secondary magnetic separation inlet, and so on.

[0103] Example 6

[0104] like Figure 3 As shown, Example 4 is repeated, except that the device includes two stages of magnetic poles 3 and inner tubes 4 connected in series. The two stages of magnetic poles and inner tubes 4 are connected in series in such a way that the magnetic material outlet 7 of the first stage inner tube 4 is connected to the material and gas inlet 6 of the second stage inner tube 4, and so on.

[0105] Example 7

[0106] Example 6 was repeated, except that the apparatus further included an oxidizing gas nozzle 14, which was disposed at the oxidizing gas inlet 5 and was tilted so that the gas outlet end was higher than the gas inlet end. The angle between the oxidizing gas nozzle and the horizontal plane was 45°.

[0107] Example 8

[0108] Example 5 was repeated, except that the apparatus further included an oxidizing gas nozzle 14, which was disposed at the oxidizing gas inlet 5 and was tilted so that the gas outlet end was higher than the gas inlet end. The angle between the oxidizing gas nozzle and the horizontal plane was 45°.

[0109] Example 9

[0110] Example 7 was repeated, except that a gas flow monitoring unit was provided at the oxidizing gas inlet 5 .

[0111] The magnetic pole 3 is an electromagnet.

[0112] A magnetic pole cleaning unit is also provided at the magnetic pole 3 .

[0113] A temperature monitoring unit is provided on the side wall of the fluidized roasting zone A.

[0114] A gas flow monitoring unit is provided at the material and gas inlet 6 .

[0115] A gas flow monitoring unit is provided at the secondary gas inlet 10 .

[0116] Example 10

[0117] Example 8 was repeated, except that a gas flow monitoring unit was provided at the oxidizing gas inlet 5 .

[0118] The magnetic pole 3 is an electromagnet.

[0119] A magnetic pole cleaning unit is also provided at the magnetic pole 3 .

[0120] A temperature monitoring unit is provided on the side wall of the fluidized roasting zone A.

[0121] A gas flow monitoring unit is provided at the material and gas inlet 6 .

[0122] A gas flow monitoring unit is provided at the secondary gas inlet 10 .

[0123] Example 11

[0124] An integrated system for magnetic separation and roasting of iron ore, comprising the integrated device for magnetic separation and roasting of iron ore, a grinding device, an inert gas source, an oxidizing gas source, and a non-magnetic material collection device as shown in Example 9. The discharge port of the grinding device is connected to the material and gas inlet of the integrated device for iron ore roasting via a material conveying pipeline, and a first gas pipeline connected to the inert gas source is provided on the pipe body of the material conveying pipeline. The inert gas source is connected to the gas inlet of the integrated device for iron ore roasting via a second gas pipeline. The oxidizing gas source is connected to the oxidizing gas inlet of the integrated device for iron ore roasting via a third gas pipeline. The non-magnetic material collection device is arranged below the non-magnetic material outlet 8.

[0125] A screening device is provided at the discharge port of the grinding device, and the sieve hole diameter of the screening device is 3 mm.

[0126] Example 12

[0127] An integrated system for magnetic separation and roasting of iron ore, comprising the integrated device for magnetic separation and roasting of iron ore, a grinding device, an inert gas source, an oxidizing gas source, and a non-magnetic material collection device as shown in Example 10. The discharge port of the grinding device is connected to the material and gas inlet of the integrated device for iron ore roasting via a material conveying pipeline, and a first gas pipeline connected to the inert gas source is provided on the pipe body of the material conveying pipeline. The inert gas source is connected to the gas inlet of the integrated device for iron ore roasting via a second gas pipeline. The oxidizing gas source is connected to the oxidizing gas inlet of the integrated device for iron ore roasting via a third gas pipeline. The non-magnetic material collection device is arranged below the non-magnetic material outlet 8.

[0128] A screening device is provided at the discharge port of the grinding device, and the sieve hole diameter of the screening device is 3 mm.

[0129] Example 13

[0130] Example 11 was repeated, except that the two-stage serially connected magnetic poles 3 and inner tubes 4 in the iron ore magnetic separation and roasting integrated device described in Example 9 were replaced with single-stage magnetic poles 3 and inner tubes 4.

[0131] Example 14

[0132] Example 11 was repeated, except that the two-stage serially connected magnetic poles 3 and inner tubes 4 in the iron ore magnetic separation and roasting integrated device described in Example 9 were replaced with four-stage serially connected magnetic poles 3 and inner tubes 4.

[0133] Example 15

[0134] Example 11 was repeated, except that the two-stage serially connected magnetic poles 3 and inner tubes 4 in the iron ore magnetic separation and roasting integrated device described in Example 9 were replaced with six-stage serially connected magnetic poles 3 and inner tubes 4.

[0135] Application Example 1

[0136] The integrated magnetic separation and roasting system for iron ore shown in Example 11 is used to carry out integrated magnetic separation and roasting of iron ore, comprising the following steps:

[0137] 1) After grinding and screening 10 kg of iron ore, a mixed small-particle material with a D90 of 3 mm is obtained. The mixed small-particle material is passed from the material and gas inlet into an 80°C drying magnetic separation zone under the action of a 1.0 m / s nitrogen gas flow and moves upward. The magnetic material is attracted by the magnetic pole and discharged from the magnetic material outlet into the magnetic material conveying pipe, and then into the transition zone. The non-magnetic material is discharged from the non-magnetic material outlet.

[0138] 2) Nitrogen gas with a flow rate of 1.0 m / s is introduced into the transition zone through the second gas pipeline. Under the action of the nitrogen flow, the magnetic material in the transition zone enters the fluidized calcination zone through the calcination zone inlet.

[0139] 3) Air with a flow rate of 2 m / s is introduced into the fluidized bed roasting zone, and the fluidized bed roasting zone is heated. The magnetic material reacts at 800° C. for 0.5 h to complete the magnetic separation roasting.

[0140] Wherein, the magnetic field strength of the magnetic pole is 0.5T.

[0141] After the roasting was completed, 7.8 kg of roasted product was obtained. The composition of the roasted product was detected, and the content of Fe2O3 was 96.3%, and the yield was 94.6%.

[0142] The same batch of iron ore and the same parameters as those in Application Example 1 were used to conduct the experiment, except that the iron ore magnetic separation and roasting integrated system used was replaced. The results shown in Table 1 were obtained.

[0143] Comparative Example

[0144] The iron ore from the same batch as in Application Example 1 was directly placed in a roasting furnace, and after passing air at a flow rate of 2 m / s, it was reacted at 800° C. for 0.5 h to complete the roasting. The roasted product was tested, and the results were shown in Table 1.

[0145] Table 1

[0146]

[0147]

[0148] The above experimental results show that the integrated device and system for magnetic separation and roasting of iron ore provided by the present invention sets the magnetic separation and roasting steps of iron ore in the same device, which can effectively shorten the process flow, save energy consumption, and improve the overall efficiency of the process. The negative pressure exhaust unit and the multi-stage series magnetic separation structure effectively improve the purity of the roasting product and ensure the quality of the final product.

Claims

1. An integrated device for magnetic separation and roasting of iron ore, characterized by: The device comprises an outer shell (1), a partition (2), a magnetic pole (3) and an inner tube (4); the partition (2) is arranged inside the outer shell (1) and divides the interior of the outer shell (1) into an upper chamber and a lower chamber, the magnetic pole (3) and the inner tube (4) are arranged in the lower chamber, the upper chamber as a whole constitutes a fluidized roasting zone (A), and an oxidizing gas inlet (5) is provided on the side wall of the upper chamber; The inner tube (4) is vertically arranged in the lower chamber and the upper end of the inner tube (4) is connected to the partition (2); a material and gas inlet (6) is provided at the bottom of the inner tube (4); a magnetic material outlet (7) and a non-magnetic material outlet (8) are respectively provided on both sides of the upper part of the side wall of the inner tube (4); the magnetic pole (3) is located outside the inner tube (4) and is arranged opposite to the magnetic material outlet (7); The interior of the inner tube (4) as a whole constitutes a drying magnetic separation zone (B); a roasting zone feed port (9) is provided on the plate body of the partition (2) on the side close to the magnetic material outlet (7); below the roasting zone feed port (9) is a transition zone (C), and a secondary gas inlet (10) is provided at the bottom of the transition zone (C); the magnetic material outlet (7) is connected to the roasting zone feed port (9) through the transition zone (C); and heating mechanisms are provided inside both the drying magnetic separation zone (B) and the fluidized roasting zone (A).

2. The device according to claim 1, characterized in that: The non-magnetic material outlet (8) is arranged opposite to the magnetic material outlet (7).

3. The device according to claim 1, characterized in that: The outside of the non-magnetic material outlet (8) is connected to a negative pressure exhaust unit.

4. The device according to claim 1, characterized in that: A sieve plate (11) is provided at the magnetic material outlet (7) and / or the non-magnetic material outlet (8) and / or the roasting zone feed inlet (9).

5. The device according to claim 4, characterized in that: The sieve plate (11) has a sieve hole diameter of 1 to 5 mm.

6. The device according to claim 5, characterized in that: The sieve plate (11) has a sieve hole diameter of 1 to 3 mm.

7. The device according to any one of claims 1 to 6, characterized in that: The device further comprises a non-magnetic material discharge pipe (12); the non-magnetic material discharge pipe (12) is arranged outside the non-magnetic material outlet (8), one end of the non-magnetic material discharge pipe (12) is connected to the non-magnetic material outlet, and the other end is connected to an external negative pressure exhaust unit; and / or The device further comprises a magnetic material conveying pipe (13); the magnetic material conveying pipe (13) is arranged outside the magnetic material outlet (7), one end of the magnetic material conveying pipe (13) is connected to the magnetic material outlet (7), and the other end is connected to the transition zone (C); the magnetic pole (3) is arranged on the side wall of the magnetic material conveying pipe (13) opposite to the magnetic material outlet (7).

8. The device according to claim 7, characterized in that: The horizontal distance between the magnetic pole (3) and the side wall of the inner tube (4) is 0.2-1.5 m.

9. The device according to claim 8, characterized in that: The horizontal distance between the magnetic pole (3) and the side wall of the inner tube (4) is 0.5-1 m.

10. The device according to claim 7, characterized in that: The non-magnetic material discharge pipe (12) and / or the magnetic material conveying pipe (13) are both vertical or inclined channels from top to bottom.

11. The device according to claim 7, characterized in that: The device comprises m levels of magnetic material conveying pipes (13) connected in series, wherein the value of m is 2 to 6; wherein the m levels of magnetic material conveying pipes (13) are connected in series in the following manner: in the first level magnetic material conveying pipe (13), a secondary magnetic separation inlet is provided on the side wall of the pipe body on the same side below the magnetic pole (3), the secondary magnetic separation inlet is connected to the second level magnetic material conveying pipe (13), a secondary magnetic pole (3) is provided on the side wall of the second level magnetic material conveying pipe (13), and the secondary magnetic pole (3) is arranged opposite to the secondary magnetic separation inlet, and so on.

12. The device according to any one of claims 1-6, 8-11, characterized in that: The device comprises n levels of magnetic poles (3) and inner tubes (4) connected in series, with n ranging from 2 to 6. The n levels of magnetic poles (3) and inner tubes (4) are connected in series in the following manner: the magnetic material outlet (7) of the first inner tube (4) is connected to the material and gas inlet (6) of the second inner tube (4), and so on.

13. The device according to claim 7, characterized in that: The device comprises n levels of magnetic poles (3) and inner tubes (4) connected in series, with n ranging from 2 to 6. The n levels of magnetic poles (3) and inner tubes (4) are connected in series in the following manner: the magnetic material outlet (7) of the first inner tube (4) is connected to the material and gas inlet (6) of the second inner tube (4), and so on.

14. The device according to any one of claims 1-6, 8-11, and 13, characterized in that: The device further comprises an oxidizing gas nozzle (14), which is arranged at the oxidizing gas inlet (5), and the oxidizing gas nozzle (14) is inclined so that the gas outlet end is higher than the gas inlet end.

15. The device according to claim 7, characterized in that: The device further comprises an oxidizing gas nozzle (14), which is arranged at the oxidizing gas inlet (5), and the oxidizing gas nozzle (14) is inclined so that the gas outlet end is higher than the gas inlet end.

16. The device according to claim 12, characterized in that: The device further comprises an oxidizing gas nozzle (14), which is arranged at the oxidizing gas inlet (5), and the oxidizing gas nozzle (14) is inclined so that the gas outlet end is higher than the gas inlet end.

17. The device according to claim 14, characterized in that: The angle between the oxidizing gas nozzle and the horizontal plane is 30~75°.

18. The device according to claim 15 or 16, characterized in that: The angle between the oxidizing gas nozzle and the horizontal plane is 30~75°.

19. The device according to claim 17, characterized in that: The angle between the oxidizing gas nozzle and the horizontal plane is 40~60°.

20. The device according to claim 18, characterized in that: The angle between the oxidizing gas nozzle and the horizontal plane is 40~60°.

21. The device according to any one of claims 1-6, 8-11, 13, 15-17, 19-20, characterized in that: A gas flow monitoring unit is provided at the oxidizing gas inlet (5); and / or The magnetic pole (3) is an electromagnet; and / or The magnetic pole (3) is also provided with a magnetic pole cleaning unit; and / or A temperature monitoring unit is provided on the side wall of the fluidized roasting zone (A); and / or A gas flow monitoring unit is provided at the material and gas inlet (6); and / or A gas flow monitoring unit is provided at the secondary gas inlet (10).

22. The device according to claim 7, characterized in that: A gas flow monitoring unit is provided at the oxidizing gas inlet (5); and / or The magnetic pole (3) is an electromagnet; and / or The magnetic pole (3) is also provided with a magnetic pole cleaning unit; and / or A temperature monitoring unit is provided on the side wall of the fluidized roasting zone (A); and / or A gas flow monitoring unit is provided at the material and gas inlet (6); and / or A gas flow monitoring unit is provided at the secondary gas inlet (10).

23. The device according to claim 12, characterized in that: A gas flow monitoring unit is provided at the oxidizing gas inlet (5); and / or The magnetic pole (3) is an electromagnet; and / or The magnetic pole (3) is also provided with a magnetic pole cleaning unit; and / or A temperature monitoring unit is provided on the side wall of the fluidized roasting zone (A); and / or A gas flow monitoring unit is provided at the material and gas inlet (6); and / or A gas flow monitoring unit is provided at the secondary gas inlet (10).

24. The device according to claim 14, characterized in that: A gas flow monitoring unit is provided at the oxidizing gas inlet (5); and / or The magnetic pole (3) is an electromagnet; and / or The magnetic pole (3) is also provided with a magnetic pole cleaning unit; and / or A temperature monitoring unit is provided on the side wall of the fluidized roasting zone (A); and / or A gas flow monitoring unit is provided at the material and gas inlet (6); and / or A gas flow monitoring unit is provided at the secondary gas inlet (10).

25. An integrated system for magnetic separation and roasting of iron ore, characterized by: The system comprises an integrated iron ore magnetic separation and roasting device, a grinding device, an inert gas source, an oxidizing gas source and a non-magnetic material collecting device according to any one of claims 1 to 24; the discharge port of the grinding device is connected to the material and gas inlet of the iron ore roasting integrated device through a material conveying pipeline, and a first gas pipeline connected to the inert gas source is provided on the pipe body of the material conveying pipeline; the inert gas source is connected to the gas inlet of the iron ore roasting integrated device through a second gas pipeline; the oxidizing gas source is connected to the oxidizing gas inlet of the iron ore roasting integrated device through a third gas pipeline; and the non-magnetic material collecting device is arranged below the non-magnetic material outlet (8).

26. The system according to claim 25, characterized in that: A screening device is provided at the discharge port of the grinding device; the sieve hole diameter of the screening device is 1-5 mm.

27. The system according to claim 26, characterized in that: A screening device is provided at the discharge port of the grinding device; the sieve hole diameter of the screening device is 1-3 mm.

28. An integrated method for magnetic separation and roasting of iron ore applied to the system according to any one of claims 25 to 27, characterized in that: The method comprises the following steps: 1) After grinding and screening, the iron ore enters the drying magnetic separation zone from the material and gas inlet under the action of inert airflow and moves upward. The magnetic material is attracted by the magnetic pole and enters the transition zone from the magnetic material outlet, and the non-magnetic material is discharged from the non-magnetic material outlet; 2) Inert gas is introduced into the transition zone through the second gas pipeline, and the magnetic material enters the fluidized calcination zone through the calcination zone inlet under the action of the inert gas flow; 3) An oxidizing gas is introduced into the fluidized bed roasting zone, and the magnetic material reacts at 500-1000°C for 0.1-1h to complete the magnetic separation roasting.

29. The integrated method for magnetic separation and roasting of iron ore according to claim 28, characterized in that: The magnetic field strength of the magnetic pole is 0.05~1.5T; and / or The inert gas is nitrogen, and the flow rate of the inert gas is 0.1-2 m / s; and / or The oxidizing gas is oxygen or air, and the flow rate of the oxidizing gas is 0.3-3 m / s; and / or The temperature in the drying magnetic separation zone is 0-200°C; and / or The heating method in the fluidized roasting zone and / or the drying magnetic separation zone is electric heating.

30. The integrated method for magnetic separation and roasting of iron ore according to claim 29, characterized in that: The magnetic field strength of the magnetic pole is 0.1-1.0T; and / or The oxidizing gas is air; and / or The temperature in the drying magnetic separation zone is 50-100°C.

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