A raw material suspension preheating magnetization roasting system and process

Abstract

The invention discloses a raw material suspension preheating magnetization roasting system and process, which relates to the technical field of metallurgy and mineral engineering. The raw material suspension preheating magnetization roasting system comprises a reducing material bin, a reducing agent bin, a multi-stage suspension preheating unit, a magnetization roasting insulation furnace and a cooling unit. The reducing material bin and the reducing agent bin discharge ports are respectively connected to the multi-stage suspension preheating unit, so that the raw material is mixed with the reducing agent after being pretreated in the multi-stage suspension preheating unit; the multi-stage suspension preheating unit is connected to the feeding port of the magnetization roasting insulation furnace, and the discharge port of the magnetization roasting insulation furnace is connected to the cooling unit. The raw material suspension preheating magnetization roasting system and process provided by the invention have a short process flow, uniform heating of materials, low production cost, light environmental pollution, high comprehensive utilization rate, excellent product cost performance, and significant energy saving and emission reduction; the scope of application is wide and has broad application prospects; the heat can be fully recycled and utilized to reduce heat energy loss.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy and mineral engineering, and in particular to a raw material suspension preheating magnetization roasting system and process. Background Art

[0002] There are a large number of low-grade iron ore resources in my country, and the iron grade of these iron ores is generally between 20% and 50%. Low-grade iron ore is usually enriched and reused by physical and chemical beneficiation methods. These beneficiation methods have problems such as low recovery rate and high recovery cost. Therefore, the utilization rate of low-grade iron ore is very low at present.

[0003] Magnetization roasting is one of the effective methods for processing low-grade iron ore. It is a process of removing volatile substances from iron ore in a heated state and reducing high-valent iron to low-valent iron. The magnetization roasting process of the traditional production process is implemented in a vertical kiln or a rotary kiln. The vertical kiln production process is relatively backward, prone to over-burning and under-burning, low iron ore reduction rate, and cannot process raw materials such as limonite and siderite that are prone to thermal pulverization. The rotary kiln production process overcomes the above-mentioned shortcomings of the vertical kiln to a certain extent, but the heat consumption is very high, and there are production and operation problems such as ring formation, crust formation, and the appearance of sinter.

[0004] In order to improve the roasting and magnetization effects, some new magnetization roasting furnaces have appeared. For example, CN101392989 discloses a suspended magnetization roasting furnace, which roasts the ore through a roaster, resulting in insufficient or partial over-roasting of the ore, and the degree of magnetization is not thorough. CN101775486 discloses a closed magnetization reduction furnace, the magnetization roasting chamber of which is closed. This structure has a cumbersome preparation process, and the magnetization effect of the ore is not ideal. At the same time, the existing magnetization roasting furnace has a small volume and limited production capacity, which cannot meet the needs of large-scale industrial production.

[0005] The purpose of the present invention is to provide a magnetic roasting furnace which has the advantages of simple structure and process, compactness, stronger practicality, etc. compared with existing magnetic roasting systems such as suspended magnetic roasting furnaces, flash furnaces, and rotary kilns, and has a wide range of applications. It can be widely used in materials such as hematite, siderite, limonite, high-iron bauxite, red mud, etc., and has broad application prospects. Summary of the invention

[0006] The purpose of the present invention is to: in view of the above-mentioned problems, the present invention provides a raw material suspension preheating magnetization roasting system and process, which has a series of advantages such as short process flow, uniform heating of materials, low production cost, light environmental pollution, high comprehensive utilization rate, excellent product cost performance, significant energy saving and emission reduction, and a wide range of applications. It can be widely used in materials such as hematite, siderite, limonite, high-iron bauxite, red mud, etc., and has broad application prospects.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A raw material suspension preheating magnetized roasting system comprises a reducing material bin, a reducing agent bin, a multi-stage suspension preheating unit, a magnetized roasting insulation furnace and a cooling unit, wherein the reducing material bin and the reducing agent bin discharge ports are respectively connected to the multi-stage suspension preheating unit, so that the raw material is pretreated in the multi-stage suspension preheating unit and then mixed with the reducing agent; the multi-stage suspension preheating unit is connected to the feeding port of the magnetized roasting insulation furnace, and the discharge port of the magnetized roasting insulation furnace is connected to the cooling unit.

[0009] In the prior art, suspended magnetized roasting usually uses gas as a reducing agent; while in the present invention, coal powder is set as a reducing agent in the reducing agent silo to improve the efficiency of magnetized roasting. Due to the adoption of the above technical scheme, the raw materials are suspended in the air flow in the multi-stage suspended preheating unit for rapid heat exchange and uniform heating; the preheated materials and the reducing agent are mixed in the multi-stage suspended preheating unit and then fed into the magnetized roasting insulation furnace for magnetized roasting, which can prevent the coal powder from being added too early and burning in advance during the preheating process, effectively improve the reduction efficiency of the reducing agent, and save the amount of reducing agent; the multi-stage suspended preheating unit is composed of 3 to 5 stages of suspended preheaters, and the number of suspended preheaters can be appropriately increased or decreased according to the magnetized roasting temperature and heat exchange efficiency; the entire raw material suspended preheating magnetized roasting system has a short process flow, low production cost, and a wide range of application, and can be widely used in materials such as hematite, siderite, limonite, high-iron bauxite, red mud, etc., and has broad application prospects.

[0010] Furthermore, the multi-stage suspension preheating unit includes a first-stage suspension preheater, a second-stage suspension preheater, a third-stage suspension preheater and a suspension preheating furnace; the smoke inlet of the first-stage suspension preheater is connected to the smoke outlet of the second-stage suspension preheater, and the discharge port is connected to the smoke inlet of the second-stage suspension preheater, the smoke inlet of the second-stage suspension preheater is connected to the smoke outlet of the third-stage suspension preheater, and the discharge port is connected to the feed port of the suspension preheating furnace, the smoke inlet of the third-stage suspension preheater is connected to the smoke outlet of the suspension preheating furnace, and the discharge port is connected to the magnetization roasting and insulation furnace; the discharge port of the reducing agent silo is connected to the smoke inlet of the first-stage suspension preheater, and the discharge port of the reducing agent silo is connected to the smoke inlet of the third-stage suspension preheater.

[0011] Due to the adoption of the above technical solution, a multi-stage suspended preheater is used to increase the material heat exchange time, which can ensure the heat exchange effect, reduce the outlet temperature of the induced draft fan, and reduce the heat loss of the system; the gas generated by the magnetized roasting and insulation furnace is slowly passed into the multi-stage suspended preheating unit through the regulating valve, so that the heat in the magnetized roasting and insulation furnace is recycled and utilized, thereby saving energy and reducing emissions.

[0012] Furthermore, the cooling unit comprises a non-contact water-cooling furnace and a contact air-cooling device; the magnetized roasting and insulation furnace is connected to the non-contact water-cooling furnace via a vibrating ore discharger, and the magnetized roasting and insulation furnace (12) and the non-contact water-cooling furnace (14) are an integral structure; and the discharge port of the non-contact water-cooling furnace is connected to the feed port of the contact air-cooling device.

[0013] Due to the adoption of the above technical scheme, the raised cone in the middle of the vibrating ore discharger rises to a certain height into the magnetized roasting and insulation furnace, and the material inside the magnetized roasting and insulation furnace is ensured to have a certain looseness and air permeability during the vibration process; the magnetized roasting and insulation furnace and the non-contact water-cooling furnace are an integral structure, which has a high heat utilization rate and a good magnetization effect compared with the structure in which the magnetized roasting and insulation furnace and the non-contact water-cooling furnace are separately arranged in the prior art; the magnetized roasting and insulation furnace is connected with the non-contact water-cooling furnace, which can realize oxidation-free cooling of high-temperature iron ore and improve the magnetic properties of the roasted ore.

[0014] Furthermore, the contact air cooling device is connected to a hot blast furnace smoke inlet, and the hot blast furnace smoke outlet is connected to the suspension preheating furnace smoke inlet.

[0015] Due to the adoption of the above technical solution, the cold air introduced into the contact air cooling device absorbs the heat of the material and becomes hot air, and the hot air is introduced into the hot air furnace to fully utilize its heat.

[0016] Furthermore, it also includes a dust removal unit, which includes a dust collector and an induced draft fan, and the induced draft fan is respectively connected to the smoke outlet of the first-stage suspension preheater and the dust collector.

[0017] Due to the adoption of the above technical solution, the dust in the flue gas is collected by the dust collector to prevent it from being released into the air to pollute the environment, which is green and environmentally friendly.

[0018] Furthermore, the magnetized roasting insulation furnace is divided into an outer insulation furnace and an inner insulation furnace. The outer insulation furnace adopts thermal insulation materials, and the inner insulation furnace adopts high thermal conductivity materials. The inner insulation furnace has a number of gas holes evenly distributed around the circumference for temperature compensation.

[0019] By adopting the above technical solution, the heat energy loss of the magnetization roasting and holding furnace is reduced, and the production cost is reduced.

[0020] Correspondingly, the present invention also discloses a raw material suspension preheating magnetization roasting process, comprising the following steps:

[0021] A. The raw material is fed into the multi-stage suspension preheating unit and quickly exchanges heat with the flue gas in the suspension preheating unit. The dusty flue gas enters the first-stage suspension preheater and the second-stage suspension preheater. The material and the flue gas are separated. The material is fed into the suspension preheating furnace for suspension roasting preheating. The flue gas is taken away by the induced draft fan and enters the dust collector. The dust contained in the flue gas is collected by the dust collector, and the exhaust gas is directly discharged;

[0022] B. The high-temperature powdered material and the reducing agent after roasting and preheating in the suspension preheating furnace are fed into the third-stage suspension preheater, and the high-temperature powdered material and the reducing agent are mixed and fed into the magnetization roasting and holding furnace;

[0023] C. After the magnetization roasting and holding furnace magnetization roasting for 30-60 minutes, the magnetization roasting product is fed into the non-contact water-cooling furnace through a vibrating ore discharger;

[0024] D. The non-contact water-cooling furnace cools the material to below 200°C and discharges it into the contact air-cooling equipment. After the material is cooled to room temperature in the contact air-cooling equipment, it is collected in the finished product warehouse.

[0025] Due to the adoption of the above technical scheme, it has a series of advantages such as short process flow, uniform heating of materials, low production cost, light environmental pollution, high comprehensive utilization rate, excellent product cost performance, significant energy saving and emission reduction, etc., and has a wide range of applications. It can be widely used in materials such as hematite, siderite, limonite, high-iron bauxite, red mud, etc., and has broad application prospects.

[0026] Furthermore, in step A, the preheating temperature of the raw material in the suspension preheating furnace is 600-1000° C., and the preheating time is 1-3 minutes.

[0027] Furthermore, in step B, the preheated raw material and the reducing agent are mixed in a mass ratio of 100:3 to 10.

[0028] Furthermore, the raw material has a particle size of -200 mesh accounting for more than 80%, and the reducing agent has a particle size of -200 mesh accounting for more than 90%.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] 1. The process of the present invention is short, the materials are heated evenly, the production cost is low, the environmental pollution is light, the comprehensive utilization rate is high, the product has excellent cost performance, and the energy saving and emission reduction are remarkable.

[0031] 2. The present invention has a wide range of applications and can be widely used in materials such as hematite, siderite, limonite, high-iron bauxite, red mud, etc., and has broad application prospects.

[0032] 3. The present invention can realize non-oxidative cooling of high-temperature iron ore and improve the magnetic properties of roasted ore.

[0033] 4. The present invention can fully recycle and utilize heat and reduce heat energy loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the structure of the raw material suspension preheating magnetization roasting system of the present invention;

[0035] Figure 2 It is a process flow chart of the raw material suspension preheating magnetization roasting system of the present invention.

[0036] Markings in the figure: 1-reducing agent silo, 2-reducing agent feeder, 3-first stage suspension preheater, 4-second stage suspension preheater, 5-third stage suspension preheater, 6-suspension preheating furnace, 7-dust collector, 8-induced draft fan, 9-reducing agent silo, 10-reducing agent feeder, 11-hot air furnace, 12-magnetization roasting and insulation furnace, 13-vibrating ore discharger, 14-non-contact water-cooling furnace, 15-contact air cooling equipment. DETAILED DESCRIPTION

[0037] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0038] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with 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.

[0039] Example 1

[0040] A raw material suspension preheating magnetization roasting system, such as Figure 1 , Figure 2 As shown, it includes a reducing material silo 1, a reducing agent silo 9, a multi-stage suspension preheating unit, a magnetized roasting and insulation furnace 12 and a cooling unit. The discharge ports of the reducing material silo 1 and the reducing agent silo 9 are respectively connected to the multi-stage suspension preheating unit, so that the raw materials are pretreated in the multi-stage suspension preheating unit and then mixed with the reducing agent; the multi-stage suspension preheating unit is connected to the feed port of the magnetized roasting and insulation furnace 12, and the discharge port of the magnetized roasting and insulation furnace 12 is connected to the cooling unit.

[0041] The multi-stage suspension preheating unit is composed of 3 to 5 stages of suspension preheaters. The number of suspension preheaters can be appropriately increased or decreased according to the magnetization roasting temperature and heat exchange efficiency. In this embodiment, the multi-stage suspension preheating unit is composed of 3 stages of suspension preheaters. The reducing agent in the reducing agent silo 9 is coal powder. Compared with the prior art that usually uses gas as a reducing agent for suspension magnetization roasting, the use of coal powder as a reducing agent can improve the efficiency of magnetization roasting. The preheated material and the reducing agent are mixed in the multi-stage suspension preheating unit and then fed into the magnetization roasting insulation furnace 12 for magnetization roasting, which can prevent the coal powder from being added too early and burning in advance during the preheating process, effectively improve the reduction efficiency of the reducing agent, and save the amount of reducing agent.

[0042] The multi-stage suspension preheating unit comprises a first-stage suspension preheater 3, a second-stage suspension preheater 4, a third-stage suspension preheater 5 and a suspension preheating furnace 6; the smoke inlet of the first-stage suspension preheater 3 is connected to the smoke outlet of the second-stage suspension preheater 4, and the discharge port is connected to the smoke inlet of the second-stage suspension preheater 4; the smoke inlet of the second-stage suspension preheater 4 is connected to the smoke outlet of the third-stage suspension preheater 5, and the discharge port is connected to the feed port of the suspension preheating furnace 6; the smoke inlet of the third-stage suspension preheater 5 is connected to the smoke outlet of the suspension preheater 4, and the discharge port is connected to the feed port of the suspension preheating furnace 6; The flue gas outlet of the floating preheating furnace 6 is connected, and the discharge port is connected to the magnetization roasting and holding furnace 12; the discharge port of the reducing material silo 1 is connected to the flue gas inlet of the first-stage suspension preheater 3, and a reducing material feeder 2 is provided between the reducing material silo 1 and the first-stage suspension preheater 3; the discharge port of the reducing agent silo 9 is connected to the flue gas inlet of the third-stage suspension preheater 5, and a reducing agent feeder 10 is provided between the reducing agent silo 9 and the third-stage suspension preheater 5, and the reducing material feeder 2 and the reducing agent feeder 10 are spiral feeders.

[0043] Air lock valves are provided between the discharge port of the first-stage suspension preheater 3 and the smoke inlet of the second-stage suspension preheater 4, between the discharge port of the second-stage suspension preheater 4 and the feed port of the suspension preheating furnace 6, and at the discharge port of the third-stage suspension preheater 5.

[0044] The cooling unit includes a non-contact water-cooled furnace 14 and a contact air-cooled device 15; the magnetized roasting and heat preservation furnace 12 is connected to the non-contact water-cooled furnace 14 through a vibrating ore-discharging machine 13, and the magnetized roasting and heat preservation furnace 12 and the non-contact water-cooled furnace 14 are an integral structure, which has a high heat utilization rate and a good magnetization effect compared with the structure in which the magnetized roasting and heat preservation furnace 12 and the non-contact water-cooled furnace 14 are separately arranged in the prior art; the discharge port of the non-contact water-cooled furnace 14 is connected to the feed port of the contact air-cooled device 15. The raised cone in the middle of the vibrating ore-discharging machine 13 rises to a certain height in the magnetized roasting and heat preservation furnace 12, and during the vibration process, the materials inside the magnetized roasting and heat preservation furnace 12 are ensured to have a certain looseness and air permeability.

[0045] The contact air cooling device 15 is connected to the smoke inlet of the hot blast furnace 11 , and the smoke outlet of the hot blast furnace 11 is connected to the smoke inlet of the suspension preheating furnace 6 .

[0046] Gas flow valves are provided between the magnetization roasting and holding furnace 12 and the third-stage suspension preheater 5 , between the contact air cooling device 15 and the smoke inlet of the hot blast stove 11 , and at the smoke outlet of the hot blast stove 11 .

[0047] It also includes a dust removal unit, which includes a dust collector 7 and an induced draft fan 8. The induced draft fan 8 is connected to the smoke outlet of the first-stage suspension preheater 3 and the dust collector 7 respectively.

[0048] The first-stage suspension preheater 3, the second-stage suspension preheater 4, the third-stage suspension preheater 5, the suspension preheating furnace 6, the hot air furnace 11, the dust collector 7, the magnetization roasting and insulation furnace 12, and the non-contact water cooling furnace 14 are respectively equipped with temperature measuring elements and pressure elements to monitor the preheating, magnetization roasting and cooling processes in real time.

[0049] The hot blast furnace 11 is heated by spraying pulverized coal, fuel oil or natural gas and igniting air.

[0050] The magnetized roasting insulation furnace 12 is divided into an outer insulation furnace and an inner insulation furnace. The outer insulation furnace adopts thermal insulation materials, and the inner insulation furnace adopts high thermal conductivity materials. The inner insulation furnace has a plurality of gas holes evenly distributed around the circumference for compensating temperature.

[0051] The entire raw material suspension preheating magnetization roasting system is under negative pressure.

[0052] Accordingly, this embodiment also provides a raw material suspension preheating magnetization roasting process, comprising the following steps:

[0053] A. The raw material is fed into the multi-stage suspension preheating unit and quickly exchanges heat with the flue gas in the suspension preheating unit. The dusty flue gas enters the first-stage suspension preheater 3 and the second-stage suspension preheater 4. The material and the flue gas are separated. The material is fed into the suspension preheating furnace 6 for suspension roasting preheating. The flue gas is taken away by the induced draft fan 8 and enters the dust collector 7. The dust contained in the flue gas is collected by the dust collector, and the waste gas is directly discharged;

[0054] B. The high-temperature powdered material and the reducing agent after roasting and preheating in the suspension preheating furnace 6 are fed into the third-stage suspension preheater 5, and the high-temperature powdered material and the reducing agent are mixed and fed into the magnetization roasting and holding furnace 12;

[0055] C. After the magnetization roasting and holding furnace 12 is magnetized and roasted for 30 to 60 minutes, the magnetized roasting product is fed into the non-contact water-cooling furnace 14 through the vibrating ore discharger 13;

[0056] D. The non-contact water cooling furnace 14 cools the material to below 200°C and discharges it into the contact air cooling device 15. After the material is cooled to room temperature in the contact air cooling device 15, it is collected in the finished product warehouse.

[0057] In step A, the preheating temperature of the raw material in the suspension preheating furnace 6 is 600-1000° C., and the preheating time is 1-3 minutes.

[0058] In step B, the preheated raw material and the reducing agent are mixed in a mass ratio of 100:3 to 10.

[0059] The raw material has a particle size of 200 mesh accounting for more than 80%, and the reducing agent has a particle size of 200 mesh accounting for more than 90%.

[0060] The magnetization roasting time in the magnetization roasting and holding furnace in step C is determined according to the type of raw materials and process conditions.

[0061] In step D, the hot air passing through the contact air cooling device 15 is introduced into the hot air furnace 11 to fully utilize its heat.

[0062] Example 2

[0063] The total iron content of a hematite in Liaoning is 39.78%, of which the magnetic iron content is only 0.42%. The raw material suspension preheating magnetization roasting system in Example 1 is used for magnetization roasting, and the hematite is made into -200 mesh 85%, preheated to 700℃ by the raw material suspension preheating magnetization roasting system in Example 1, and fed to the magnetization roasting holding furnace 12 together with 5% coal powder, and the roasting time is 30min; the cooling unit is cooled by water, and the cooling water flow rate is 2m / s, and the material is cooled to below 200℃ and discharged. The final magnetic susceptibility reaches 96%.

[0064] Example 3

[0065] The Fe2O3 content of a high-iron bauxite in Yunnan is 22.36%. The raw material suspension preheating magnetization roasting system in Example 1 is used for magnetization roasting, and the bauxite is made into -200 mesh 90%, preheated to 900℃ by the raw material suspension preheating magnetization roasting system in Example 1, and fed to the magnetization roasting holding furnace 12 together with 10% coal powder, and the roasting time is 60min; the cooling unit is cooled by water, and the cooling water flow rate is 2m / s, and the material is cooled to below 200℃ and discharged. The final magnetic susceptibility reaches 90%.

[0066] The principles and implementation methods of the present invention are described in this article using specific embodiments. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0067] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0068] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A raw material suspension preheating magnetization roasting system, comprising a reducing material silo (1), a reducing agent silo (9), a multi-stage suspension preheating unit, a magnetization roasting holding furnace (12) and a cooling unit, characterized in that: The discharge ports of the reducing material bin (1) and the reducing agent bin (9) are respectively connected to a multi-stage suspension preheating unit, so that the raw materials are pretreated in the multi-stage suspension preheating unit and then mixed with the reducing agent; the multi-stage suspension preheating unit is connected to the feed port of the magnetized roasting and heat-insulating furnace (12), and the discharge port of the magnetized roasting and heat-insulating furnace (12) is connected to the cooling unit; the multi-stage suspension preheating unit comprises a first-stage suspension preheater (3), a second-stage suspension preheater (4), a third-stage suspension preheater (5) and a suspension preheating furnace (6); the first-stage suspension The smoke inlet of the preheater (3) is connected to the smoke outlet of the second-stage suspension preheater (4), and the discharge port is connected to the smoke inlet of the second-stage suspension preheater (4); the smoke inlet of the second-stage suspension preheater (4) is connected to the smoke outlet of the third-stage suspension preheater (5), and the discharge port is connected to the feed port of the suspension preheating furnace (6); the smoke inlet of the third-stage suspension preheater (5) is connected to the smoke outlet of the suspension preheating furnace (6), and the discharge port is connected to the magnetization roasting and heat preservation furnace (12); the discharge port of the feed bin (1) is connected to the first-stage suspension The preheater (3) is connected to the flue gas inlet, and the reductant silo (9) is connected to the flue gas inlet of the third-stage suspension preheater (5); the cooling unit includes a non-contact water-cooling furnace (14) and a contact air-cooling device (15); the magnetized roasting and heat-insulating furnace (12) is connected to the non-contact water-cooling furnace (14) via a vibrating ore discharger (13), and the magnetized roasting and heat-insulating furnace (12) and the non-contact water-cooling furnace (14) are an integral structure; the non-contact water-cooling furnace (14) is connected to the contact air-cooling device ( 15) a feed port; the raised cone in the middle of the vibrating ore discharger (13) is raised into the magnetized roasting and heat preservation furnace (12) to a certain height, and during the vibration process, the material inside the magnetized roasting and heat preservation furnace (12) is ensured to have a certain looseness and air permeability; the magnetized roasting and heat preservation furnace (12) is divided into an outer layer heat preservation furnace and an inner layer heat preservation furnace, the outer layer heat preservation furnace adopts heat preservation and heat insulation materials, and the inner layer heat preservation furnace adopts high thermal conductivity materials, and the inner layer heat preservation furnace is evenly distributed with a plurality of coal gas holes for temperature compensation in the circumference, and the reducing agent in the reducing agent silo (9) is coal powder.

2. The raw material suspension preheating magnetization roasting system according to claim 1, characterized in that: The contact air cooling device (15) is connected to the smoke inlet of the hot blast furnace (11), and the smoke outlet of the hot blast furnace (11) is connected to the smoke inlet of the suspension preheating furnace (6).

3. The raw material suspension preheating magnetization roasting system according to claim 1, characterized in that: It also comprises a dust removal unit, the dust removal unit comprising a dust collector (7) and an induced draft fan (8), the induced draft fan (8) being respectively connected to the smoke outlet of the first-stage suspension preheater (3) and the dust collector (7).

4. A raw material suspension preheating magnetization roasting process, characterized in that: The following steps are involved: A. The raw material is fed into a multi-stage suspension preheating unit and rapidly exchanges heat with the flue gas in the suspension preheating unit. The dusty flue gas enters the first-stage suspension preheater (3) and the second-stage suspension preheater (4). The material and the flue gas are separated. The material is fed into a suspension preheating furnace (6) for suspension roasting preheating. The flue gas is taken away by an induced draft fan (8) and enters a dust collector (7). The dust contained in the flue gas is collected by the dust collector and the waste gas is directly discharged. B. The high-temperature powdered material preheated by roasting in the suspension preheating furnace (6) and the reducing agent in the reducing agent silo (9) are fed into the third-stage suspension preheater (5), and the high-temperature powdered material and the reducing agent are mixed and then fed into the magnetization roasting and heat-insulating furnace (12), wherein the reducing agent is coal powder; C. After the magnetization roasting and holding furnace (12) has been magnetized for 30 to 60 minutes, the magnetization roasting product is fed into a non-contact water-cooling furnace (14) through a vibrating ore discharger (13); D. The non-contact water cooling furnace (14) cools the material to below 200°C and discharges it into the contact air cooling device (15). After the material is cooled to room temperature in the contact air cooling device (15), it is collected in the finished product bin.

5. The raw material suspension preheating magnetization roasting process according to claim 4, characterized in that: In step A, the preheating temperature of the raw material in the suspension preheating furnace (6) is 600-1000° C., and the preheating time is 1-3 minutes.

6. The raw material suspension preheating magnetization roasting process according to claim 4, characterized in that: In step B, the preheated raw material and the reducing agent are mixed in a mass ratio of 100:3-10.

7. The raw material suspension preheating magnetization roasting process according to claim 4, characterized in that: The raw material-200 mesh particle size accounts for more than 80%, and the reducing agent-200 mesh particle size accounts for more than 90%.

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