A hot separation system for high temperature reduction products

Abstract

A high-temperature reduction product hot-state separation system, which comprises a rotary kiln and a synchronous hot screening and cooling device arranged downstream of the rotary kiln. The synchronous hot screening and cooling device comprises a cylinder. A screen is arranged in the cylinder. The outer wall of the cylinder is covered with cooling water pipes. The internal area surrounded by the screen is a screening zone, and the interlayer area formed between the screen and the cylinder is a cooling zone. The synchronous hot screening and cooling device is arranged obliquely, wherein a high-temperature reduction product inlet and a high-temperature reduction ball outlet are arranged at the higher end and the lower end of the screening zone respectively, and a hot powder outlet is arranged at the lower end of the cooling zone. The kiln head of the rotary kiln is connected with the high-temperature reduction product inlet of the synchronous hot screening and cooling device. A transmission device is further connected with the cylinder, and the transmission device is used for driving the cylinder and the screen to rotate. The temperature loss in the traditional process is greatly reduced, the problem of excessive reduction agent caused by residual coal entering the electric furnace is effectively avoided, and the smelting efficiency is improved.

Description

Technical Field

[0001] This utility model relates to a separation device for reduction products, specifically a high-temperature hot separation system for reduction products, belonging to the field of metallurgical engineering technology. Background Technology

[0002] In the complex process of rotary kiln pre-reduction and electric arc furnace smelting of iron-containing pellets, after reduction in the rotary kiln, the reduced pellets mix with residual coal powder, coal ash, and reducing powder generated by collisions and are discharged at the kiln head. To further separate slag and iron, the reduced pellets need to be smelted in the electric arc furnace. Taking titanium concentrate as an example, after pre-reduction in the rotary kiln, the titanium concentrate pellets enter the electric arc furnace for smelting to prepare high-titanium slag. The accuracy of the reducing agent ratio is crucial during the electric arc furnace smelting of high-titanium slag. If the reduced pellets are added to the electric arc furnace together with the reducing residual coal powder, it is difficult to control the amount of reducing agent used in the furnace, posing a risk of excessive reducing agent. During reduction, the foamy slag layer in the furnace rises rapidly, leading to safety accidents such as slag overturning. Furthermore, the ash from the reducing agent entering the electric arc furnace slag will reduce the grade of the titanium slag, failing to meet the requirements for high-titanium slag. Therefore, the reduced pellets need to be separated before entering the electric arc furnace. Magnetic separation is an efficient method for separating reducing pellets from residual coal powder. However, the reducing pellets and powder have weak magnetic properties at high temperatures, requiring them to be cooled before magnetic separation. During the cooling process, the heat from the reducing pellets, powder, and residual coal powder cannot be utilized, resulting in energy loss. Furthermore, the separated room-temperature reducing pellets and powder need to be reheated to extremely high temperatures in the electric furnace, further increasing energy consumption and raising production costs. Utility Model Content

[0003] To address the problems of separating high-temperature reduction products from rotary kilns and the severe temperature loss during subsequent electric furnace smelting in existing technologies, this invention proposes a hot separation system and method for high-temperature reduction products. The core of this invention lies in the design of a synchronous hot screening and cooling device. This device mainly consists of a cylinder, an internal screen, and external cooling water pipes. The internal area enclosed by the screen forms a screening zone, while the interlayer between the screen and the cylinder constitutes a cooling zone. This invention transports the high-temperature reduction products from the rotary kiln head to the screening zone of the synchronous hot screening and cooling device. Under the combined action of gravity and rotation, the high-temperature reduction products undergo dynamic screening during their advancement, achieving efficient separation of large-diameter high-temperature reduction spheres from small-diameter hot powder through hot screening. The high-temperature reduction spheres can be directly hot-charged into the electric furnace for smelting, significantly reducing temperature loss in traditional processes and effectively avoiding excessive reducing agent caused by residual coal entering the electric furnace, thus improving smelting efficiency. In addition, the separated hot powder exchanges heat with the cooling water pipes during the sieving process, achieving preliminary cooling of the material. This innovative design combines the sieving and cooling processes into one, which not only simplifies the subsequent magnetic separation process but also significantly improves the system's thermal energy utilization efficiency.

[0004] According to the first embodiment of this utility model, a high-temperature reduction product hot separation system is provided.

[0005] A high-temperature reduction product hot separation system includes a rotary kiln and a synchronous hot screening and cooling device located downstream of the rotary kiln. The synchronous hot screening and cooling device includes a cylindrical body. A screen is installed inside the cylindrical body. The outer wall of the cylindrical body is covered with cooling water pipes. The internal area enclosed by the screen is a screening zone, and the interlayer area formed between the screen and the cylindrical body is a cooling zone. The synchronous hot screening and cooling device is inclined, wherein a high-temperature reduction product inlet and a high-temperature reduction ball outlet are respectively located at the higher and lower ends of the screening zone, and a hot powder outlet is located at the lower end of the cooling zone. The kiln head of the rotary kiln is connected to the high-temperature reduction product inlet of the synchronous hot screening and cooling device. A transmission device is also connected to the cylindrical body, which drives the cylindrical body and the screen to rotate.

[0006] In this invention, the system further includes a synchronous cooling magnetic separator. The synchronous cooling magnetic separator comprises a housing. One side of the housing is a cooling wall area, and a cooling water spray device is located above the exterior of this side of the housing. The other side of the housing is a magnetic separation area, with a strong magnet located outside the housing on this side, and a magnetic powder collection chute correspondingly located above the interior of this side of the housing. The housing is inclined, and the synchronous cooling magnetic separator has a hot powder inlet and a non-magnetic powder outlet at its higher and lower ends, respectively. The hot powder outlet of the synchronous hot screening and cooling device is connected to the hot powder inlet of the synchronous cooling magnetic separator. A transmission device is also connected to the housing, which drives the housing to rotate.

[0007] Preferably, the synchronous cooling magnetic separator further includes a circulating water tank. The circulating water tank is located below the housing on the cooling wall side.

[0008] In this invention, the system also includes an electric furnace. The high-temperature reduction ball outlet of the synchronous hot screening and cooling device is connected to the feed inlet of the electric furnace.

[0009] Preferably, the magnetic powder collection chute of the synchronous cooling magnetic separator is connected to the feed inlet of the electric furnace via a conveying device.

[0010] In this invention, the system also includes an air classifier. The air classifier is equipped with a non-magnetic powder inlet, a residual coal outlet, and a coal ash outlet. The non-magnetic powder outlet of the synchronously cooled magnetic separator is connected to the non-magnetic powder inlet of the air classifier.

[0011] Preferably, the residual coal outlet of the air classifier is connected to the kiln head of the rotary kiln and / or the reducing agent inlet of the electric furnace.

[0012] In this invention, the outer wall of the cylinder is covered with two sets of cooling water pipes. One set of cooling water pipes flows in the same direction as the material inside the synchronous hot screening and cooling device, while the other set of cooling water pipes flows in the opposite direction to the material inside the synchronous hot screening and cooling device.

[0013] In this invention, the mesh size of the sieve is 2-5 mm, preferably 3-4 mm.

[0014] According to a second embodiment of the present invention, a method for hot separation of high-temperature reduction products is provided.

[0015] A method for hot separation of high-temperature reduction products, or a method for hot separation of high-temperature reduction products using the system described in the first embodiment, the method comprising the following steps:

[0016] S1. Pellet raw materials enter the rotary kiln from the kiln tail, while coal is injected into the rotary kiln from the kiln head. After the pellet raw materials undergo high-temperature reduction in the rotary kiln, the kiln head produces high-temperature reduction products including reduced pellets, reduced powder, residual coal powder, and coal ash.

[0017] S2. The high-temperature reduction product obtained in step S1 is conveyed to the synchronous hot screening and cooling device. The high-temperature reduction product enters the screening section, moves forward under the action of gravity and rotation and is screened. The high-temperature reduction balls with large particle size move to the high-temperature reduction ball outlet, and the high-temperature powder with small particle size enters the cooling zone through the screen and exchanges heat with the cooling water pipe on the outer wall of the cylinder. After preliminary cooling, the hot powder obtained moves to the hot powder outlet.

[0018] In this invention, the method further includes the following steps:

[0019] S3. The hot powder obtained in step S2 is conveyed to the synchronous cooling magnetic separator. The hot powder advances under the influence of gravity and rotation. When the hot powder rotates with the shell to the cooling wall area, it undergoes secondary heat exchange and cooling through the cooling water sprayed from the shell and the cooling water spray device. Once the hot powder cools to below the Curie point temperature, the reduced powder regains its magnetism. At this point, the reduced powder is attracted to the inner wall of the shell by the strong magnet in the other magnetic separation zone, separating it from the non-magnetic powder composed of residual coal powder and coal ash. The reduced powder is carried to the upper part without the strong magnet as the shell rotates and falls into the magnetic powder collection chute. The non-magnetic powder, after cooling, is discharged from the non-magnetic powder outlet of the shell.

[0020] In this invention, the method further includes the following steps:

[0021] S4. The high-temperature reduction balls obtained in step S2 are hot-loaded into the electric furnace and coal required for smelting is added. The high-temperature reduction balls are smelted in the electric furnace to obtain molten iron and slag.

[0022] Preferably, in step S4, the reduced powder obtained in step S3 through the magnetic powder collection chute and the high-temperature reduced balls obtained in step S2 are hot-charged into the electric furnace for smelting.

[0023] In this invention, the method further includes the following steps:

[0024] S5. The non-magnetic powder obtained in step S3 is fed to an air classifier. The non-magnetic powder is further separated by air classification, and the separated residual coal powder and coal ash are discharged through the residual coal outlet and coal ash outlet of the air classifier, respectively.

[0025] Preferably, the residual coal powder obtained in step S5 is transported to the kiln head of the rotary kiln and reused as a reducing agent in the rotary kiln.

[0026] Preferably, the residual coal powder obtained in step S5 is conveyed to the reducing agent inlet of the electric furnace and reused as the reducing agent of the electric furnace.

[0027] In this invention, the upper limit of the energy consumption evaluation index for electric furnace smelting is set as E. The mass ratio of the high-temperature reduction balls in the hot-charged electric furnace to the high-temperature reduction powder is measured as W. ghq The mass ratio of the high-temperature reducing balls and reducing powder in the hot-charged electric furnace was measured to be W. rhf The smelting temperature of the electric furnace is set to T. d ℃. Adjust the temperature of the high-temperature reduction ball at the outlet of the synchronous hot screening and cooling device to T. ghq ℃. Adjust the temperature of the reduced powder in the magnetic powder collection chute of the synchronous cooling magnetic separator to T. rhf ℃. The total iron content in the high-temperature reducing spheres was determined to be TFe. hq The metallization rate of iron in the high-temperature reduction sphere was determined to be M. hqFe The total iron content (TFe) in the reducing powder was determined to be TFe. hf The metallization rate of iron in the reduced powder was determined to be M. hfFe . Makes:

[0028]

[0029] Where: KT is the energy consumption factor affected by temperature, with a value ranging from 1 to 2; KM is the energy consumption factor affected by metallization rate, with a value ranging from 2 to 3.5; C hq-Fe Specific heat capacity of non-ferrous components in high-temperature reducing spheres, Kcal / (kg·℃); C hf-Fe The specific heat capacity of the non-ferrous component in the reducing powder is expressed in kcal / (kg·℃).

[0030] Preferably, the temperature of the high-temperature reduction ball at the outlet of the high-temperature reduction ball in the synchronous hot screening and cooling device is adjusted by controlling the rotation speed of the synchronous hot screening and cooling device. At the same time, the temperature of the reduction powder in the magnetic powder collection chute of the synchronous cooling magnetic separator is adjusted by controlling the rotation speed of the synchronous cooling magnetic separator and the cooling water flow rate of the cooling water spray device, so that the energy consumption evaluation index of electric furnace smelting in step S4 is less than or equal to E.

[0031] To address the problems of separating high-temperature reduction products in rotary kilns and the severe temperature loss during subsequent electric furnace smelting in existing technologies, this invention proposes a hot-state separation system for high-temperature reduction products. The core of this invention lies in the design of a synchronous hot screening and cooling device. This device mainly consists of a cylinder, an internal screen, and external cooling water pipes. The internal area enclosed by the screen forms a screening zone, while the interlayer between the screen and the cylinder constitutes a cooling zone. This invention transports the high-temperature reduction products produced at the rotary kiln head to the screening zone of the synchronous hot screening and cooling device. Under the combined action of gravity and rotation, the high-temperature reduction products undergo dynamic screening during their advancement, achieving efficient separation of large-diameter high-temperature reduction spheres from small-diameter hot powder through hot screening. The high-temperature reduction spheres can be directly hot-charged into the electric furnace for smelting, significantly reducing temperature loss in traditional processes and effectively avoiding excessive reducing agent caused by residual coal entering the electric furnace, thus improving smelting efficiency. In addition, the separated hot powder exchanges heat with the cooling water pipes during the sieving process, achieving preliminary cooling of the material. This innovative design combines the sieving and cooling processes into one, which not only simplifies the subsequent magnetic separation process but also significantly improves the system's thermal energy utilization efficiency.

[0032] Specifically, in the synchronous hot screening and cooling device, the cylinder is typically made of high-temperature resistant material to withstand the temperature of the high-temperature reduction products produced by the rotary kiln. The length and diameter of the cylinder are designed according to actual production needs to ensure that the residence time of the high-temperature reduction products in the cylinder is sufficient to complete the screening and preliminary cooling process. The built-in screen is a key component for achieving dynamic screening; its aperture size and distribution determine the screening accuracy and efficiency. Since the size of the high-temperature reduction balls is generally 3~10mm, the screen aperture size is designed to be 2~5mm (preferably 3~4mm, for example, 3mm) to ensure accurate separation of the high-temperature reduction balls from the hot powder. The screen is typically made of high-temperature resistant and wear-resistant material to ensure long-term stable operation. The shape of the screen can be planar or spiral to adapt to different screening requirements and improve screening efficiency. An external cooling water pipe surrounds the outside of the cylinder, creating a cooling zone in the interlayer area between the cylinder and the screen. The layout and spacing of the cooling water pipes, as well as the temperature and flow rate of the cooling water, are designed according to the cooling requirements to ensure that the hot powder can effectively absorb heat during the sieving process and achieve a preliminary cooling effect.

[0033] Preferably, the outer wall of the cylinder is covered with two sets of cooling water pipes. The overall water flow direction of one set of cooling water pipes (from inlet 1 to outlet 1, e.g.) Figure 3 As shown, the flow direction of the material in the synchronous hot screening and cooling device is the same, mainly used to quickly remove the heat of small-diameter powder entering the cooling zone during the screening process, thereby improving cooling efficiency; the overall water flow direction of the other set of cooling water pipes (from inlet 2 to outlet 2, as shown) is as follows: Figure 3 As shown, the flow of material in the synchronous hot screening and cooling device is opposite to that of the material, creating a counter-current cooling effect, further ensuring the uniformity and stability of the cooling of the hot powder. This design not only improves cooling efficiency but also helps reduce energy consumption and enhances the overall system's heat recovery and utilization level.

[0034] In this invention, the synchronous hot screening and cooling device is inclined, and a transmission device (not shown in the drawings) is connected to the cylinder. This transmission device drives the cylinder and screen to rotate, achieving dynamic screening and preliminary cooling of the material simultaneously during its forward movement under the combined effects of gravity and rotation. Preferably, the cylinder and screen of the synchronous hot screening and cooling device are concentric or coaxial. The cylinder and screen rotate at a certain speed, which must ensure a moderate residence time of the material on the screen, allowing for sufficient screening while avoiding excessive wear. The speed setting needs to be comprehensively considered based on factors such as the material's properties, particle size distribution, and the screen's aperture size. During rotation, the material is subjected to gravity and centrifugal force. Large-diameter high-temperature reducing balls, due to their larger mass, tend to roll along the screen surface and move forward, eventually exiting from the high-temperature reducing ball outlet. Small-diameter hot powders (including reducing powder, residual coal powder, and coal ash) more easily pass through the screen holes and fall into the cooling zone, exchanging heat with the cooling water pipes on the outer wall of the cylinder for preliminary cooling.

[0035] It should be noted that the specific structure of the transmission device used in the aforementioned synchronous hot screening and cooling device is not limited, as long as it can realize the function of driving the cylinder and screen to rotate and adjusting the speed. For example, the transmission device can be set up to be similar to the device structure that drives the cylinder to rotate in a rotary kiln. The transmission device of a rotary kiln is usually composed of a motor, a reducer, and a coupling, which together drive the cylinder to rotate. A gear ring is installed in the middle of the cylinder of the rotary kiln, which drives the cylinder to rotate through gear transmission.

[0036] As a preferred embodiment, this invention innovatively integrates a synchronous cooling magnetic separation device based on a synchronous hot screening and cooling device. The device consists of a shell, with its inner sides divided into two functional areas: a cooling wall area and a magnetic separation area. The cooling wall area is primarily used for secondary cooling of the hot powder, while the magnetic separation area is used for magnetic separation of the cooled powder. In the cooling wall area, a cooling water spray device is installed above the outer surface of the shell. This device evenly sprays cooling water onto the outer wall of the shell, forming a cooling water flow that exchanges heat with the hot powder, achieving rapid cooling. The cooled water flow collects in a circulating water tank below the shell and, through a circulating pump, is sent back to the cooling water spray device for recycling, thereby improving water resource utilization efficiency. The magnetic separation area is equipped with strong magnets. When the hot powder cools to below the Curie point temperature, the reduced powder gradually regains its magnetism and is attracted to the inner wall of the shell by the magnets. In other words, at this point, the magnetic separation area immediately performs dynamic magnetic separation of the reduced powder, thus achieving effective separation from non-magnetic powders such as residual coal powder and coal ash. As the shell continues to rotate, the magnetic powder (i.e., the reducing powder) is carried to the upper area without strong magnets, and then falls into the magnetic powder collection chute for collection. This "cooling-magnetic separation" synchronous device and process has multiple advantages: (1) precise temperature control magnetic separation: the reducing powder is separated as soon as it reaches the magnetic separation temperature during the cooling process, avoiding over-cooling and maximizing the retention of residual heat; (2) efficient utilization of thermal energy: the separated reducing powder still maintains a high temperature and can be directly hot-charged into the electric furnace together with the high-temperature reducing balls, further reducing the temperature loss in the smelting process; (3) optimized resource recovery: by combining short-distance cooling with instant magnetic separation, the recovery rate and purity of the reducing powder are significantly improved, reducing the waste and loss of raw materials, and providing higher quality raw materials for subsequent smelting processes.

[0037] It should be noted that in the design of the synchronous cooling magnetic separator, the cooling wall zone and the magnetic separation zone each have specific responsibilities. These two zones are designed independently of the rotational movement of the entire device housing. This means that regardless of how the housing rotates, the relative positions and functions of these two zones remain unaffected, maintaining their inherent characteristics. Correspondingly, the positions of the cooling water spray device above the cooling wall zone and the strong magnets located outside the housing in the magnetic separation zone also remain unchanged. Furthermore, a transmission device (not shown in the attached diagram) is connected to the housing of the synchronous cooling magnetic separator. This transmission device drives the housing to rotate. Similarly, the specific structure of the transmission device is not limited, as long as it can achieve the function of driving the housing to rotate and adjusting the rotation speed.

[0038] In this invention, the high-temperature reduction product separation system further includes an electric furnace. The electric furnace is used to further smelt the high-temperature reduction pellets processed by the rotary kiln and synchronous hot screening and cooling device, as well as the reduction powder separated by synchronous cooling magnetic separation device. The high-temperature environment inside the electric furnace allows iron oxides to be reduced to metallic iron and separated from the slag. To improve smelting efficiency and product quality, parameters such as the electric furnace feed, smelting temperature, and smelting time must be precisely controlled.

[0039] In this invention, the high-temperature reduction product separation system further includes an air classifier. The air classifier effectively separates residual coal powder and coal ash from the non-magnetic powder by adjusting the air speed and direction, discharging them through different outlets. The separated residual coal powder can be reused as a reducing agent in a rotary kiln or electric furnace, while the coal ash is treated as solid waste, thereby maximizing resource utilization and minimizing waste emissions. As an important component of the entire high-temperature reduction product hot separation system, the introduction of the air classifier not only improves separation efficiency but also further optimizes the environmental performance of the entire process.

[0040] Based on the above-mentioned high-temperature reduction product hot separation system, this invention also proposes a corresponding high-temperature reduction product hot separation method. The main implementation steps of this method are as follows:

[0041] (1) The dried pellet raw material enters the rotary kiln from the tail end for high-temperature reduction, while coal is injected into the kiln as a reducing agent from the kiln head. After high-temperature reduction, the pellets are reduced into pellets. At the same time, some pellets break during the reduction process, producing pellet powder, which is then reduced to produce reduced powder. After the coal reaction is completed, coal ash remains, while some coal is not completely decomposed and becomes residual coal (or residual coal powder). That is, after high-temperature reduction in the rotary kiln, the kiln head produces reduced pellets, reduced powder, residual coal powder, and coal ash.

[0042] (2) The high-temperature reduction products are screened using a synchronous hot screening and cooling device. The synchronous hot screening and cooling device consists of two parts: a screening zone and a cooling zone. The screening zone is equipped with a screen (e.g., a screen aperture of 3 mm). The high-temperature reduction products enter through the feed inlet (i.e., the high-temperature reduction product inlet) and are screened under the influence of gravity and rotation. Small-sized (e.g., less than 3 mm) hot powders (including reducing powder, residual coal powder, and coal ash) pass through the screen and enter the cooling zone, while large-sized (e.g., greater than 3 mm) high-temperature reduction pellets move to the high-temperature reduction pellet outlet. The cooling zone is in contact with the outer wall of the cylinder and exchanges heat with the cooling water pipes on the outer wall. The hot powders undergo preliminary cooling in the synchronous hot screening and cooling device. The high-temperature reduction pellets are kept at a high temperature on the screen to avoid contact with the outer wall of the cylinder and are discharged through the high-temperature reduction pellet outlet or enter the reduction pellet hopper (i.e., a buffer hopper is set between the synchronous hot screening and cooling device and the subsequent process equipment).

[0043] For example, in traditional processes, high-temperature reduction pellets of titanium concentrate are fed into an electric furnace along with hot powders such as residual coal powder and coal ash. This leads to an excessively high reducing agent content in the furnace, causing a thickened foam layer or even leakage, posing a serious safety threat. This invention achieves separation of reduction pellets and powders at high temperatures through hot screening, preventing coal powder from entering the furnace and avoiding cold screening, thus reducing heat loss. By adjusting the rotation speed of the cylinder and screen, the residence time of the high-temperature reduction product within the device can be controlled, thereby controlling the separation efficiency of the high-temperature reduction pellets and hot powders. Furthermore, the outer wall of the cylinder is equipped with two sets of water pipes, one flowing in the same direction and the other in the opposite direction, for heat exchange and cooling. By controlling the switching of the in- and out-of-direction water pipes, the cooling degree of the hot powder can be regulated.

[0044] (3) After initial cooling, the hot powder enters a synchronous cooling magnetic separator for further cooling and magnetic separation. The housing of the synchronous cooling magnetic separator is divided into two functional areas: a cooling wall area and a magnetic separation area. For example, Figure 3-4 As shown, the left side of the cylinder wall is the cooling wall zone, and the right side is the magnetic separation zone. Upon entering the device, because the temperature of the hot powder after initial cooling may still exceed the Curie point, the metallized material (i.e., the reduced powder) is non-magnetic. All powdered material moves towards the discharge port (i.e., the non-magnetic powder outlet) under the influence of gravity and rotation. The material's temperature is conducted to the shell wall, heating it. Once the shell wall rotates to the cooling zone, it is cooled by cooling water sprayed from the cooling water spray device. This process is repeated to gradually cool the material. After the metallized material cools below the Curie point, it gradually regains its magnetism and is attracted to the inner wall of the shell by the magnetic field on the right side, separating from the non-magnetic powder (including residual coal powder and coal ash). The magnetic powder is carried by the shell wall to the upper part where there is no strong magnet and falls into the magnetic powder collection chute. Thus, during the gradual cooling process, once the metallized powder regains sufficient magnetism, it is promptly separated by magnetic separation, avoiding further cooling and preserving as much residual heat as possible. Finally, the non-magnetic residual coal and coal ash are cooled and discharged from the shell for separation and recycling.

[0045] (4) The high-temperature reduction balls and hot reduction powder obtained by simultaneous hot screening and cooling device and simultaneous cooling magnetic separation device are hot-charged into the electric furnace and accurately mixed with the coal required for smelting, and smelted together in the electric furnace. During the smelting process, the iron oxides in the reduction balls and reduction powder are further reduced to metallic iron and melted into molten iron. Titanium dioxide and other impurities react to form high-titanium slag that floats on top of the molten iron. After smelting, the molten iron is discharged from the discharge port at the bottom of the electric furnace and separated from the slag, realizing the separation of titanium and iron. The titanium dioxide in the high-titanium slag can be further processed and purified by acid dissolution, chlorination and other methods to produce titanium dioxide or sponge titanium.

[0046] (5) Preferably, the residual coal powder and coal ash obtained by screening through the synchronous cooling magnetic separator can be further separated by air separation. The residual coal and coal ash have different qualities, which can be separated by adjusting the air speed of the air separator. The separated residual coal can be reused as a reducing agent in rotary kilns or electric furnaces, while the coal ash is treated as solid waste.

[0047] Furthermore, during the separation process of the high-temperature reducing balls and hot powder, the temperature of the high-temperature reducing balls at the outlet is adjusted by controlling the rotation speed of the synchronous hot screening and cooling device. Simultaneously, the temperature of the reduced powder in the magnetic powder collection chute is adjusted by controlling the rotation speed of the synchronous cooling magnetic separator and the cooling water flow rate of the cooling water spray device. This invention also uses an energy consumption evaluation index to measure the energy-saving effects of the synchronous hot screening and cooling device and the synchronous cooling magnetic separator.

[0048]

[0049] Where: E represents the upper limit of the energy consumption evaluation index for electric furnace smelting. W ghq This indicates the mass percentage of the high-temperature reduction balls that are hot-charged into the electric furnace compared to the mass percentage of the high-temperature reduction balls in the reduction powder. W rhf This indicates the mass percentage of the high-temperature reduction balls and reduction powder in the reduction powder that are hot-charged into the electric furnace. (T) d T indicates the smelting temperature of the electric furnace, in °C. ghq This indicates the temperature of the high-temperature reduction ball at the outlet of the synchronous hot screening and cooling device, in °C. rhf This indicates the temperature of the reduced powder in the magnetic powder collection chute of the synchronously cooled magnetic separator, in °C. TFe hq This indicates the total iron content in the high-temperature reduction pellet. M hqFe This indicates the metallization rate of iron in the high-temperature reduction pellet. (TFe) hf This indicates the total iron content in the reduced powder. M hfFe This represents the metallization rate of iron in the reducing powder. KT is the energy consumption factor affected by temperature, with a value ranging from 1 to 2. KM is the energy consumption factor affected by the metallization rate, with a value ranging from 2 to 3.5. C hq-Fe C represents the specific heat capacity of the non-ferrous component in the high-temperature reduction sphere, in kcal / (kg·℃). hf-Fe The specific heat capacity of the non-ferrous component in the reducing powder is expressed in kcal / (kg·℃).

[0050] In the above formula, all contents, proportions, metallization rates, etc., are expressed as mass percentages. E is less than or equal to 900.

[0051] It should be noted that the above formula was obtained by the inventor based on experimental and engineering applications. All calculations are based on values ​​converted to a given unit. The converted values ​​are substituted into the formula for calculation (after unit conversion, only the numerical value is substituted into the formula for calculation, not the unit; the unit is only used to adjust the magnitude of the value). After adopting the process method of this utility model, the control method obtained by this application can be used universally.

[0052] In this application, "residual coal powder" and "residual coal" are synonymous and can be used interchangeably.

[0053] In this application, the diameter of the rotary kiln is 0.5-20m, preferably 0.8-15m, more preferably 1-12m, more preferably 1.2-10m, and even more preferably 1.5-8m.

[0054] In this application, the length of the rotary kiln is 1-200m, preferably 2-150m, more preferably 3-120m, more preferably 4-100m, and even more preferably 5-80m.

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

[0056] 1. This utility model, through the design of a synchronous hot screening and cooling device, not only solves the problems of temperature loss in traditional processes and excessive reducing agent caused by residual coal entering the electric furnace, but also improves smelting efficiency and thermal energy utilization efficiency, and has significant technical advantages and economic benefits.

[0057] 2. In this utility model, the hot powder separated by the synchronous hot screening and cooling device exchanges heat with the cooling water pipe during the screening process, realizing the initial cooling of the material. This innovative design combines the screening and cooling processes into one, which not only simplifies the subsequent magnetic separation process, but also significantly improves the thermal energy utilization efficiency of the system.

[0058] 3. This utility model innovatively integrates a synchronous cooling magnetic separation device on the basis of a synchronous hot screening and cooling device. After the initial cooling by the synchronous hot screening and cooling device, the hot powder enters the synchronous cooling magnetic separation device for secondary cooling. This "cooling-magnetic separation" synchronous device and process has multiple advantages: (1) Precise temperature control magnetic separation: The reduced powder is separated as soon as it reaches the magnetic separation temperature during the cooling process, avoiding over-cooling and maximizing the retention of residual heat; (2) High-efficiency utilization of thermal energy: The separated reduced powder still maintains a high temperature and can be directly charged into the electric furnace together with the high-temperature reduced balls, further reducing the temperature loss in the smelting process; (3) Optimized resource recovery: By combining short-distance cooling with instantaneous magnetic separation, the recovery rate of the reduced powder is significantly improved, reducing the waste and loss of raw materials.

[0059] 4. This utility model also proposes to use an energy consumption evaluation index to measure the energy-saving effect of the synchronous hot screening and cooling device and the synchronous cooling magnetic separation device. By precisely controlling key parameters such as the temperature of the high-temperature reduction ball and the hot powder, effective savings in energy consumption indicators during subsequent smelting processes can be achieved. This method can significantly reduce energy consumption during the smelting process and improve overall smelting efficiency. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the structure of a high-temperature reduction product hot separation system according to the present invention;

[0061] Figure 2 This is a schematic diagram of the synchronous hot screening and cooling device in this utility model;

[0062] Figure 3 This is a schematic diagram showing the operating status of the synchronous hot screening and cooling device in this utility model;

[0063] Figure 4 This is a schematic diagram of the synchronous cooling magnetic separation device in this utility model;

[0064] Figure 5 This is a schematic diagram showing the operating state of the synchronous cooling magnetic separator in this utility model.

[0065] Figure label:

[0066] 1: Rotary kiln; 2: Synchronous hot screening and cooling device; 201: Cylinder; 202: Screen; 203: Cooling water pipe; 204: High-temperature reduction product inlet; 205: High-temperature reduction ball outlet; 206: Hot powder outlet; 3: Synchronous cooling magnetic separator; 301: Shell; 302: Cooling water spray device; 303: Circulating water tank; 304: Strong magnet; 305: Magnetic powder collection chute; 306: Hot powder inlet; 307: Non-magnetic powder outlet; 4: Electric furnace; 401: Feed inlet; 402: Reducing agent inlet; 5: Air classifier; 501: Non-magnetic powder inlet; 502: Residual coal outlet; 503: Coal ash outlet. Detailed Implementation

[0067] The technical solution of this utility model is illustrated below. The scope of protection of this utility model includes, but is not limited to, the following embodiments.

[0068] According to the first embodiment of this utility model, a high-temperature reduction product hot separation system is provided.

[0069] A high-temperature reduction product hot separation system includes a rotary kiln 1 and a synchronous hot screening and cooling device 2 located downstream of the rotary kiln 1. The synchronous hot screening and cooling device 2 includes a cylinder 201. A screen 202 is installed inside the cylinder 201. The outer wall of the cylinder 201 is covered with cooling water pipes 203. The internal area enclosed by the screen 202 is a screening zone, and the interlayer area formed between the screen 202 and the cylinder 201 is a cooling zone. The synchronous hot screening and cooling device 2 is inclined, wherein a high-temperature reduction product inlet 204 and a high-temperature reduction ball outlet 205 are respectively provided at the higher and lower ends of the screening zone, and a hot powder outlet 206 is provided at the lower end of the cooling zone. The kiln head of the rotary kiln 1 is connected to the high-temperature reduction product inlet 204 of the synchronous hot screening and cooling device 2. A transmission device is also connected to the cylinder 201, which drives the cylinder 201 and the screen 202 to rotate.

[0070] In this invention, the system further includes a synchronous cooling magnetic separator 3. The synchronous cooling magnetic separator 3 includes a housing 301. One side of the housing 301 is a cooling wall area, and a cooling water spray device 302 is provided above the exterior of this side of the housing 301. The other side of the housing 301 is a magnetic separation area, and a strong magnet 304 is provided outside the exterior of this side of the housing 301. A magnetic powder collection chute 305 is correspondingly provided above the interior of this side of the housing 301. The housing 301 is inclined, and the synchronous cooling magnetic separator 3 has a hot powder inlet 306 and a non-magnetic powder outlet 307 at the higher and lower ends of the housing 301, respectively. The hot powder outlet 206 of the synchronous hot screening and cooling device 2 is connected to the hot powder inlet 306 of the synchronous cooling magnetic separator 3. A transmission device is also connected to the housing 301, which drives the housing 301 to rotate.

[0071] Preferably, the synchronous cooling magnetic separator 3 further includes a circulating water tank 303. The circulating water tank 303 is disposed below the housing 301 on the cooling wall area side.

[0072] In this invention, the system also includes an electric furnace 4. The high-temperature reduction ball outlet 205 of the synchronous hot screening and cooling device 2 is connected to the feed inlet 401 of the electric furnace 4.

[0073] Preferably, the magnetic powder collection chute 305 of the synchronous cooling magnetic separator 3 is connected to the feed inlet 401 of the electric furnace 4 via a conveying device.

[0074] In this invention, the system also includes an air classifier 5. The air classifier 5 is equipped with a non-magnetic powder inlet 501, a residual coal outlet 502, and a coal ash outlet 503. The non-magnetic powder outlet 307 of the synchronous cooling magnetic separator 3 is connected to the non-magnetic powder inlet 501 of the air classifier 5.

[0075] Preferably, the residual coal outlet 502 of the air classifier 5 is connected to the kiln head of the rotary kiln 1 and / or the reducing agent inlet 402 of the electric furnace 4.

[0076] In this invention, the outer wall of the cylinder 201 is covered with two sets of cooling water pipes 203. One set of cooling water pipes 203 has the same water flow direction as the material inside the synchronous hot screening and cooling device 2, while the other set of cooling water pipes 203 has the opposite water flow direction to the material inside the synchronous hot screening and cooling device 2.

[0077] In this invention, the mesh size of the screen 202 is 2~5mm, preferably 3~4mm.

[0078] Example 1

[0079] like Figure 1-2 As shown, a high-temperature reduction product hot separation system includes a rotary kiln 1 and a synchronous hot screening and cooling device 2 located downstream of the rotary kiln 1. The synchronous hot screening and cooling device 2 includes a cylinder 201. A screen 202 is installed inside the cylinder 201. The outer wall of the cylinder 201 is covered with cooling water pipes 203. The internal area enclosed by the screen 202 is a screening zone, and the interlayer area formed between the screen 202 and the cylinder 201 is a cooling zone. The synchronous hot screening and cooling device 2 is inclined, wherein a high-temperature reduction product inlet 204 and a high-temperature reduction ball outlet 205 are respectively provided at the higher and lower ends of the screening zone, and a hot powder outlet 206 is provided at the lower end of the cooling zone. The kiln head of the rotary kiln 1 is connected to the high-temperature reduction product inlet 204 of the synchronous hot screening and cooling device 2. A transmission device is also connected to the cylinder 201, which drives the cylinder 201 and the screen 202 to rotate.

[0080] Example 2

[0081] The system repeats Example 1, except that it also includes an electric furnace 4. The high-temperature reduction ball outlet 205 of the synchronous hot screening and cooling device 2 is connected to the feed inlet 401 of the electric furnace 4.

[0082] Example 3

[0083] like Figure 4-5As shown, Embodiment 1 is repeated, except that the system also includes a synchronous cooling magnetic separator 3. The synchronous cooling magnetic separator 3 includes a housing 301. One side of the housing 301 is a cooling wall area, and a cooling water spray device 302 is provided above the exterior of the housing 301 on this side. The other side of the housing 301 is a magnetic separation area, and a strong magnet 304 is provided outside the housing 301 on this side. A magnetic powder collection chute 305 is correspondingly provided above the interior of the housing 301 on this side. The housing 301 is inclined, and the synchronous cooling magnetic separator 3 has a hot powder inlet 306 and a non-magnetic powder outlet 307 at the higher and lower ends of the housing 301, respectively. The hot powder outlet 206 of the synchronous hot screening and cooling device 2 is connected to the hot powder inlet 306 of the synchronous cooling magnetic separator 3. A transmission device is also connected to the housing 301, which drives the housing 301 to rotate.

[0084] Example 4

[0085] The embodiment 3 is repeated, except that the synchronous cooling magnetic separator 3 further includes a circulating water tank 303. The circulating water tank 303 is located below the housing 301 on the cooling wall area side.

[0086] Example 5

[0087] Example 4 is repeated, except that the system also includes an electric furnace 4. The high-temperature reduction ball outlet 205 of the synchronous hot screening and cooling device 2 is connected to the feed inlet 401 of the electric furnace 4.

[0088] The magnetic powder collection chute 305 of the synchronous cooling magnetic separator 3 is connected to the feed inlet 401 of the electric furnace 4 via a conveying device.

[0089] Example 6

[0090] Example 5 is repeated, except that the system also includes an air classifier 5. The air classifier 5 is equipped with a non-magnetic powder inlet 501, a residual coal outlet 502, and a coal ash outlet 503. The non-magnetic powder outlet 307 of the synchronously cooled magnetic separator 3 is connected to the non-magnetic powder inlet 501 of the air classifier 5.

[0091] Example 7

[0092] Example 6 is repeated, except that the residual coal outlet 502 of the air separator 5 is connected to the kiln head of the rotary kiln 1.

[0093] Example 8

[0094] Example 6 is repeated, except that the residual coal outlet 502 of the air classifier 5 is connected to the reducing agent inlet 402 of the electric furnace 4.

[0095] Example 9

[0096] Example 6 is repeated, except that the residual coal outlet 502 of the air classifier 5 is connected to the kiln head of the rotary kiln 1 and the reducing agent inlet 402 of the electric furnace 4.

[0097] Example 10

[0098] like Figure 3 As shown, Example 9 is repeated, except that the outer wall of the cylinder 201 is covered with two sets of cooling water pipes 203. One set of cooling water pipes 203 has the same water flow direction as the material inside the synchronous hot screening and cooling device 2, while the other set of cooling water pipes 203 has the opposite water flow direction to the material inside the synchronous hot screening and cooling device 2.

[0099] Example 11

[0100] Repeat Example 10, except that the mesh size of the screen 202 is 3.5 mm.

[0101] Example 12

[0102] Repeat Example 10, except that the mesh size of the screen 202 is 4mm.

[0103] Example 13

[0104] Repeat Example 10, except that the mesh size of the screen 202 is 3mm.

[0105] The method using the high-temperature reduction product hot separation system described in this embodiment includes the following steps:

[0106] S1. Pellet raw material enters rotary kiln 1 from the kiln tail, and coal is injected into rotary kiln 1 from the kiln head. After the pellet raw material is reduced at high temperature in rotary kiln 1, the kiln head produces high-temperature reduction products including reduced pellets, reduced powder, residual coal powder, and coal ash.

[0107] S2. The high-temperature reduction product obtained in step S1 is transported to the synchronous hot screening and cooling device 2. The high-temperature reduction product enters the screening section, moves forward under the action of gravity and rotation and is screened. The high-temperature reduction balls with a particle size greater than 3mm move to the high-temperature reduction ball outlet 205, and the high-temperature powder with a particle size less than 3mm enters the cooling zone through the screen 202 and exchanges heat with the cooling water pipe 203 on the outer wall of the cylinder 201. After preliminary cooling, the hot powder obtained moves to the hot powder outlet 206.

[0108] S3. The hot powder obtained in step S2 is conveyed to the synchronous cooling magnetic separator 3. The hot powder advances under the influence of gravity and rotation. When the hot powder rotates with the shell 301 to the cooling wall area, it undergoes secondary heat exchange and cooling through the cooling water sprayed from the shell 301 and the cooling water spray device 302. Once the hot powder cools to below the Curie point temperature, the reduced powder regains its magnetism. At this point, the reduced powder is attracted to the inner wall of the shell 301 by the strong magnet 304 in the other magnetic separation zone, separating it from the non-magnetic powder composed of residual coal powder and coal ash. The reduced powder is carried to the upper part without the strong magnet 304 as the shell 301 rotates, falling into the magnetic powder collection chute 305. The non-magnetic powder, after cooling, is discharged from the non-magnetic powder outlet 307 of the shell 301.

[0109] S4. The reducing powder obtained in step S3 through the magnetic powder collection chute 305 and the high-temperature reducing balls obtained in step S2 are hot-charged into the electric furnace 4, and the coal required for smelting is added. The high-temperature reducing balls and reducing powder are smelted in the electric furnace 4 to obtain molten iron and slag.

[0110] S5. The non-magnetic powder obtained in step S3 is conveyed to the air classifier 5. The non-magnetic powder is further separated by air classification, and the separated residual coal powder and coal ash are discharged through the residual coal outlet 502 and the coal ash outlet 503 of the air classifier 5, respectively. The residual coal powder can be conveyed to the kiln head of the rotary kiln 1 as a reducing agent for reuse in the rotary kiln 1, or it can be conveyed to the reducing agent inlet 402 of the electric furnace 4 as a reducing agent for reuse in the electric furnace 4.

Claims

1. A high-temperature reduction product hot separation system, characterized in that: The system includes a rotary kiln (1) and a synchronous hot screening and cooling device (2) located downstream of the rotary kiln (1); the synchronous hot screening and cooling device (2) includes a cylinder (201); a screen (202) is provided inside the cylinder (201); the outer wall of the cylinder (201) is covered with cooling water pipes (203); the internal area enclosed by the screen (202) is the screening area, and the interlayer area formed between the screen (202) and the cylinder (201) is the cooling area; the synchronous hot screening and cooling device ( 2) Inclined setting, wherein a high-temperature reduction product inlet (204) and a high-temperature reduction ball outlet (205) are respectively provided at the higher end and the lower end of the screening section, and a hot powder outlet (206) is provided at the lower end of the cooling zone; the kiln head of the rotary kiln (1) is connected to the high-temperature reduction product inlet (204) of the synchronous hot screening and cooling device (2); a transmission device is also connected on the cylinder (201), which is used to drive the cylinder (201) and the screen (202) to rotate.

2. The system according to claim 1, characterized in that: The system also includes a synchronous cooling magnetic separator (3); the synchronous cooling magnetic separator (3) includes a housing (301); one side of the housing (301) is a cooling wall area, and a cooling water spray device (302) is provided above the outside of the housing (301) on this side; the other side of the housing (301) is a magnetic separation area, and a strong magnet (304) is provided outside the housing (301) on this side, and a magnetic powder collection chute (305) is provided above the inside of the housing (301) on this side; the housing (301) is inclined, and the synchronous cooling magnetic separator (3) is provided with a hot powder inlet (306) and a non-magnetic powder outlet (307) at the higher end and the lower end of the housing (301) respectively; the hot powder outlet (206) of the synchronous hot screening and cooling device (2) is connected to the hot powder inlet (306) of the synchronous cooling magnetic separator (3); a transmission device is also connected to the housing (301), and the transmission device is used to drive the housing (301) to rotate.

3. The system according to claim 2, characterized in that: The synchronous cooling magnetic separator (3) also includes a circulating water tank (303); the circulating water tank (303) is located below the housing (301) on the cooling wall area side.

4. The system according to claim 3, characterized in that: The system also includes an electric furnace (4); the high-temperature reduction ball outlet (205) of the synchronous hot screening and cooling device (2) is connected to the feed inlet (401) of the electric furnace (4).

5. The system according to claim 4, characterized in that: The magnetic powder collection chute (305) of the synchronous cooling magnetic separator (3) is connected to the feed inlet (401) of the electric furnace (4) via a conveying device.

6. The system according to claim 4, characterized in that: The system also includes an air separator (5); the air separator (5) is equipped with a non-magnetic powder inlet (501), a residual coal outlet (502), and a coal ash outlet (503); wherein, the non-magnetic powder outlet (307) of the synchronous cooling magnetic separator (3) is connected to the non-magnetic powder inlet (501) of the air separator (5).

7. The system according to claim 6, characterized in that: The residual coal outlet (502) of the air separator (5) is connected to the kiln head of the rotary kiln (1) and / or the reducing agent inlet (402) of the electric furnace (4).

8. The system according to any one of claims 1-7, characterized in that: The outer wall of the cylinder (201) is covered with two sets of cooling water pipes (203); one set of cooling water pipes (203) has the same water flow direction as the material in the synchronous hot screening and cooling device (2), and the other set of cooling water pipes (203) has the opposite water flow direction to the material in the synchronous hot screening and cooling device (2).

9. The system according to any one of claims 1-7, characterized in that: The mesh size of the screen (202) is 2~5mm.

10. The system according to claim 9, characterized in that: The screen mesh (202) has a mesh size of 3~4mm.

Images