Short-flow process for smelting high titanium slag based on Consteel electric furnace

Abstract

The invention relates to the technical field of titanium slag smelting, in particular to a short-process technology for smelting high titanium slag based on a Consteel electric furnace. The method comprises the following steps: step 1, preparing raw materials: high-grade titanium concentrate and a reducing agent; wherein the use amount of the high-grade titanium concentrate is 85-90%, the total amount of ferrotitanium in the high-grade titanium concentrate is greater than 90%, and the grade is greater than 44%; the dosage of the reducing agent is 10-15%; 2, raw material feeding; in the short-flow process for smelting the high titanium slag based on the Consteel electric furnace, a mixture can directly fall into a molten pool for melting, an electrode is not in direct contact with the mixture during power transmission, electric energy can be input at the maximum power from the beginning of power transmission to the end of smelting, and the furnace can be shut down for deslagging or iron tapping in a short time in the smelting process, so that the time is effectively saved, and the production efficiency is improved. Compared with the prior art, the method has the advantages that the electric furnace smelting time of the Consteel process is greatly shortened, the time of a single heat is controlled within 60 minutes, the productivity is greatly improved, the production requirement can be more efficiently met, and the economic benefit is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of titanium slag smelting, and in particular to a short-process technology for smelting high-titanium slag based on a Consteel electric furnace. Background Art

[0002] Titanium slag products produced by the electric furnace smelting method account for more than 70% of the world's production of titanium-rich raw materials and are widely used in titanium industries such as sulfuric acid process titanium dioxide, sponge titanium, and chloride process titanium dioxide. The main raw materials for electric furnace smelting of titanium slag include titanium concentrate and reducing agents. Considering the economic balance between raw materials and products, the reducing agent used for electric furnace smelting of acid-soluble titanium slag is mainly coke. If the reducing agent (coke) is not suitable during the smelting process of acid-soluble titanium slag, it is easy to lead to a series of problems such as increased carbon content, high power consumption per ton of material, low titanium slag grade, high flue gas temperature and low molten iron temperature. Therefore, improving the technical level of titanium slag coke is of great significance to optimizing the titanium slag smelting process and improving the quality of titanium slag products.

[0003] Currently, traditional titanium slag electric furnace smelting processes are lengthy and require extensive equipment. For example, the large furnace diameter necessitates numerous silos and distribution equipment for charging, leading to increased loading and distributing equipment. Plant heights often reach 40-50 meters, necessitating significant construction investment. Furthermore, during the smelting process, electrodes come into direct contact with the mixed material, limiting power delivery and resulting in lengthy smelting times, often exceeding 60 minutes per furnace cycle. This makes it difficult to meet the demands of efficient production. Furthermore, traditional processes suffer from high energy consumption, arc instability, significant heat loss, and frequent electrode oxidation and accidental breakage, increasing energy consumption and costs. Furthermore, traditional electric furnaces have a poor operating environment, with dust easily escaping. Furnace workers must perform laborious tasks such as drilling, burning, and plugging the slag and iron openings, resulting in labor-intensive work and high smelting noise. This impacts the worker's work environment and efficiency, leading to economic losses.

[0004] In view of this, there is an urgent need for a short process based on Consteel electric furnace smelting of high titanium slag. Summary of the Invention

[0005] The purpose of the present invention is to provide a short-process process for smelting high-titanium slag based on Consteel electric furnace, which is efficient, energy-saving, environmentally friendly and easy to operate, so as to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides a short process for smelting high-titanium slag based on a Consteel electric furnace, comprising the following steps:

[0007] S1. Raw material preparation: high-grade titanium concentrate and reducing agent;

[0008] S2. Raw material loading: high-grade titanium concentrate and reducing agent are poured into the loading silo, and the raw materials are lifted to the upper surface of the loading belt by a bucket elevator. At the same time, the high-grade titanium concentrate is fed into the titanium ore bin and the reducing agent is fed into the reducing agent bin by a plow discharger. Then, the high-grade titanium concentrate and reducing agent are respectively added to the weighing hopper through the feeding belt for weighing and batching. The weighed raw materials are discharged to the mixing belt through two discharge belts for mixing. The mixed raw materials are discharged into the interior of the three batching bins through the plow discharger. Finally, the raw materials in the three batching bins are evenly fed into the electric furnace through three screw feeders.

[0009] S3. Electric furnace smelting: In the electric furnace, electric energy is transmitted to the furnace through a water-cooled conductive cross arm made of copper-steel composite plates. The electric furnace electrode at the end of the electric energy transmission leads the electric energy into the furnace for melting and smelting. During the heating process, the mixed material undergoes deep reduction to produce slag and iron separation. At the same time, the reduction process in the closed electric furnace generates a large amount of high-temperature coal gas.

[0010] S4, slag discharge operation: when slag is discharged, the electric furnace is tilted, and the titanium slag is discharged from the electric furnace outlet and collected into a slag bag. The slag bag is transported to the slag cooling room by a slag bag car for cooling, crushing, and screening to obtain titanium slag with a TiO2 content of more than 75%;

[0011] S5. Tapping operation: Controls the number of times the smelting furnace is turned on. Tapping is performed after the last slag tapping. The furnace is tilted during tapping. Molten iron is discharged from the same outlet of the furnace and then transferred to a ladle. The ladle is transported by a ladle car to the iron casting machine for casting ingots. The ingots are cast on the iron casting machine and used as raw materials in the steel plant.

[0012] S6. Gas treatment: The high-temperature gas discharged from the flue on the top of the electric furnace is cooled by a water-cooled flue, and then the dust in the gas is removed by gravity dust removal and a high-temperature metal film fine dust collector. The gas is then cooled by air and then transported to a gas tank for temporary storage before being delivered to the user.

[0013] As a further improvement of the present technical solution, in S1, the amount of high-grade titanium concentrate is 85%-90%; the amount of reducing agent is 10%-15%.

[0014] As a further improvement of the present technical solution, in S1, the total amount of high-grade ilmenite concentrate ferroilan is greater than 90%, and the grade is greater than 44%.

[0015] As a further improvement of the present technical solution, in S2, materials are continuously added to the electric furnace at a uniform speed through three screw feeders, gas sealing devices are provided under the three screw feeders, and the total feeding amount of the three screw feeders per hour is controlled at 40t, and the smelting time of a single furnace is controlled at 1h.

[0016] As a further improvement of the present technical solution, in S3, electric energy is transmitted to the electric furnace for melting and smelting through a water-cooled conductive cross arm of a copper-steel composite plate. The transformer used has a rated power of 45MVA+10% continuous overload, a primary voltage of 35KV, and 50Hz; the electrode diameter is 550mm, the pole center circle diameter is 1100mm, and the electrode lifting is automatically controlled by constant current.

[0017] As a further improvement of the present technical solution, in S3, the electric furnace electrodes are sealed using a three-stage "ring brick + nitrogen + filler" method, and the furnace cover and the furnace body are also sealed.

[0018] As a further improvement of the present technical solution, in S3, the electric furnace adopts eccentric bottom tapping for slag or iron tapping, the inner diameter of the lower furnace shell of the electric furnace is 5600mm; the total capacity is 115t and the nominal capacity is 75t.

[0019] As a further improvement of the present technical solution, in S3, during the electric furnace smelting process, when the temperature is greater than 850°C, FeO in the mixture begins to be solid-phase reduced; when the temperature reaches above 1300°C, deep reduction of FeO and other oxides is carried out; the material after deep reduction gradually melts during the continued heating and temperature increase process, and during the melting process of the material, the high-temperature molten iron and the slag liquid are separated due to the difference in density, and titanium slag is obtained at the upper part of the molten pool, and molten iron is obtained at the bottom of the molten pool.

[0020] As a further improvement of the present technical solution, in S5, the number of times the smelting furnace is heated is controlled to 3-4 times, and the amount of molten iron is controlled to 45t-50t.

[0021] As a further improvement of the present technical solution, in S6, the temperature of the high-temperature coal gas is 900°C-1000°C, the temperature is cooled to 500°C-600°C by water-cooling flue, and the temperature is cooled to below 50°C by air cooling.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. In this short-process Consteel electric furnace smelting high-titanium slag process, the mixture can drop directly into the molten molten pool, and the electrodes do not directly contact the mixture when power is supplied. In this way, electric energy can be input at maximum power from the start of power supply to the end of smelting. In addition, the furnace can be stopped for short periods of time during the smelting process to tap slag or iron, effectively saving this time. This is conducive to significantly shortening the Consteel process electric furnace smelting time. In addition, the single furnace time is controlled within 60 minutes, greatly improving production capacity and being able to more efficiently meet production needs, thereby improving economic benefits.

[0024] 2. In the short-process technology based on the Consteel electric furnace for smelting high-titanium slag, continuous charging and continuous smelting are adopted, so that the arc is stable and covered with foamy slag. The heat transfer efficiency between the arc and the molten pool is extremely high, which reduces the heat loss radiated to the refractory materials, furnace walls and furnace cover water cooling plate, thereby achieving energy saving; in addition, the electric furnace is closed and continuous charging and continuous melting are carried out while retaining iron, which not only reduces electrode oxidation consumption, but also the continuous and stable submerged arc operation greatly reduces electrode wear and reduces accidental electrode breakage, further reducing energy consumption, reducing the company's energy costs, and thus improving energy utilization efficiency.

[0025] 3. In the short-process technology based on Consteel electric furnace smelting high-titanium slag, the Consteel electric furnace is used to smelt high-titanium slag, which can greatly reduce the equipment such as distribution equipment, silos, charging equipment, electric furnace transformers and plugging machines. At the same time, it simplifies the configuration of the hydraulic system, power distribution system and SVC; not only does it reduce the height of the plant, greatly saving construction investment, but it also provides more space for equipment inspection and maintenance, making maintenance work more convenient and quick, reducing the subsequent maintenance costs, and thus reducing economic consumption.

[0026] 4. In the short-process technology based on Consteel electric furnace smelting high-titanium slag, the electric furnace is charged by spiral charging, which is conducive to keeping the furnace cover closed at all times, and the entire smelting system maintains negative pressure, effectively preventing the leakage of pollutants such as dust, making the working environment cleaner, greatly reducing labor intensity, improving workers' working conditions, and helping to improve workers' work efficiency and work enthusiasm.

[0027] 5. In the short-process technology based on the Consteel electric furnace for smelting high-titanium slag, the chemical reaction and physical conditions in the furnace cause the slag to foam and form a foamy slag layer during the smelting process. The Consteel arc is always in the molten pool, and the foamy slag forms a buffer layer around the arc, which can effectively absorb and block the propagation of noise generated by the arc, reducing the noise level of the entire smelting process, and helping to provide workers with a relatively quiet and comfortable working environment, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flowchart of the short process for smelting high-titanium slag in an electric furnace according to the present invention;

[0029] Figure 2 This is a schematic diagram of raw material loading for the short process flow of smelting high-titanium slag in an electric furnace according to the present invention;

[0030] Figure 3 This is a schematic diagram of slag and iron tapping in the short-process process of smelting high-titanium slag in an electric furnace according to the present invention. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0032] Example

[0033] according to Figure 1-Figure 3 As shown, the embodiment of the present invention provides a short process for smelting high-titanium slag based on a Consteel electric furnace, comprising the following steps:

[0034] Step 1. Raw material preparation: high-grade ilmenite concentrate and reducing agent; wherein: the amount of high-grade ilmenite concentrate is 85%-90%, the total amount of ferroilane in the high-grade ilmenite concentrate is greater than 90%, and the grade is greater than 44%; the amount of reducing agent is 10%-15%;

[0035] Step 2: Raw material loading: Pour high-grade titanium concentrate and reducing agent into the loading bin, use bucket elevator to lift the raw materials to the upper surface of the loading belt, and at the same time, use the plow type discharger ( Figure 2 The middle plow type unloader 1) puts high grade titanium concentrate into the titanium ore bin, and the reducing agent into the reducing agent bin, and then passes through the feeding belt ( Figure 2 The middle feeding belt 1 and feeding belt 1) respectively add high-grade titanium concentrate and reducing agent into the weighing hopper (high-grade titanium concentrate enters Figure 2 Middle weighing hopper 1, reducing agent enters Figure 2 The weighing hopper 2 is used to weigh the ingredients, and the weighed raw materials are passed through two unloading belts (the two unloading belts refer to Figure 2 The mixed raw materials are unloaded onto the mixing belt for mixing, which increases the mixing uniformity, reduces the process transportation and vibration, and avoids material segregation. The mixed raw materials are discharged through the plow discharger (the plow discharger includes Figure 2 The plow discharger 2 and the plow discharger 3) are respectively discharged into the interior of the three batching bins (the three batching bins refer to Figure 2 Finally, the raw materials in the three batching bins are evenly added to the electric furnace through three screw feeders. The raw materials are continuously added to the electric furnace at a uniform speed through the three screw feeders. A gas sealing device is set under the three screw feeders to prevent the gas from escaping from the material pipe during the smelting process and causing a "flash explosion" accident. The total feeding amount of the three screw feeders per hour is controlled at 40t, and the smelting time of a single furnace is controlled at 1h. At this time, the feeding amount of the three batching bins is matched with the power supply in the furnace to ensure that the materials added to the furnace can be heated and melted in time and evenly, and no pile or accumulation of materials will occur in the furnace;

[0036] Step 3, electric furnace smelting: In the electric furnace, electric energy is transmitted to the electric furnace through a copper-steel composite plate water-cooled conductive cross arm. The electric furnace electrode at the terminal of the electric energy transmission adopts a "ring brick + nitrogen + filler" three-stage seal, and the furnace cover and the furnace body are also sealed. The electric energy is introduced into the furnace for melting and smelting, providing energy for the melting and smelting of the material; the electric energy is transmitted to the electric furnace for melting and smelting through a copper-steel composite plate water-cooled conductive cross arm. The transformer used has a rated power of 45MVA+10% continuous overload, a primary voltage of 35KV, and 50Hz; the electrode diameter is 550mm, the pole center circle diameter is 1100mm, and the electrode lifting is automatically controlled by constant current; during the heating process, the mixed material is deeply reduced to produce slag and iron separation. At the same time, the reduction process in the closed electric furnace produces a large amount of high-temperature coal gas. The electric furnace adopts eccentric furnace bottom slag or iron tapping, and the inner diameter of the lower furnace shell of the electric furnace is 5600mm; the total capacity is 115t, and the nominal capacity is 75t;

[0037] In addition, during the electric furnace smelting process, when the temperature is greater than 850°C, FeO in the mixture begins to be solid-phase reduced; when the temperature reaches above 1300°C, FeO and other oxides are deeply reduced; the deeply reduced material gradually melts during the continuous heating process, and during the melting process, the high-temperature molten iron and slag liquid separate due to the difference in density, obtaining titanium slag at the top of the molten pool and molten iron at the bottom of the molten pool;

[0038] Step 4, slag tapping operation: When tapping, the electric furnace is tilted, and the titanium slag is discharged from the electric furnace outlet and collected into a slag bag. The slag bag is transported to the slag cooling room by a slag bag car for cooling, crushing, and screening to obtain titanium slag with a TiO2 content of more than 75%;

[0039] Step 5: Tapping operation: Control the number of smelting furnaces. The number of tapping times is controlled at 3-4 times. The amount of molten iron is controlled at 45t-50t. Once the amount of molten iron reaches the upper limit, tapping must be performed immediately to avoid adverse effects on the smelting process and equipment. Tapping is performed after the last slag tapping. The electric furnace is tilted during tapping. The molten iron is discharged from the same outlet of the electric furnace and then connected to the ladle. The ladle is transported by the ladle car to the iron casting machine for casting ingots. The iron ingots are cast on the iron casting machine and used as raw materials for the steel plant.

[0040] During the smelting process, the iron-tapping operation requires the electric furnace to be tilted. This smelting mode belongs to the "retain iron and discharge slag" operation type. During this operation, both iron and slag are discharged through the same discharge port. Moreover, after the smelting of each furnace is completed, the ladle must be manually tilted to discharge the slag liquid from the discharge port. In addition, the specifications of the slag ladle used for slag tapping and the molten iron ladle used for iron tapping are the same. The same specifications of molten iron ladle cars can be used to transport the high-temperature liquid to the corresponding process, sharing the same track at the bottom of the furnace body, and transporting on separate tracks at appropriate locations in the factory.

[0041] Step 6. Gas treatment: The high-temperature gas discharged from the flue on the top of the electric furnace has a temperature of 900℃-1000℃. It is cooled by the water-cooled flue to 500℃-600℃. The dust in the gas is removed by gravity dust removal and high-temperature metal film fine dust collector. It is then cooled by air cooling to below 50℃. After that, it is transported to the gas tank for temporary storage and then transported to the user.

[0042] In the invention, high-grade titanium concentrate and reducing agent are first prepared in proportion and fed into the electric furnace through a series of loading, batching and feeding processes. This not only improves the uniformity of raw material mixing and reduces material segregation, but also, through measures such as continuous feeding at a uniform speed by a spiral feeder and the provision of a gas sealing device, the material in the furnace is heated evenly and safety accidents are avoided. For example, during the electric furnace smelting process, solid-phase reduction and deep reduction are carried out when the temperature reaches a specified value, which can also effectively improve the reduction effect and smelting efficiency of the material, fully separate the high-temperature molten iron from the slag liquid, and ultimately obtain high-quality titanium slag and molten iron. Moreover, through the treatment of slag tapping, iron tapping and gas treatment, on the one hand, the operating process is simplified and the transportation and treatment of high-temperature liquids are facilitated. On the other hand, energy recovery and utilization are achieved while reducing environmental pollution, thereby improving the efficiency, energy saving, environmental protection and safety of the entire smelting process.

[0043] The mixed material can fall directly into the molten molten pool, and the electrodes do not directly contact the mixed material when power is supplied. In this way, electric energy can be input at maximum power from the start of power supply to the end of smelting. In addition, the furnace can be stopped for a short period of time during the smelting process to discharge slag or iron, which effectively saves this part of time and is conducive to significantly shortening the smelting time of the Consteel process electric furnace. In addition, the time of a single furnace is controlled within 60 minutes, which greatly improves production capacity and can more efficiently meet production needs, thereby improving economic benefits.

[0044] The continuous charging and continuous smelting methods are adopted to make the arc stable and covered with foam slag (the arc refers to a high-temperature discharge phenomenon formed between the electrode and the material). The heat transfer efficiency between the arc and the molten pool is extremely high, which reduces the heat loss radiated to the refractory materials, furnace walls and furnace cover water cooling plate, thereby achieving energy saving; in addition, the closed electric furnace and continuous charging and continuous melting in the iron retention state not only reduce the electrode oxidation consumption, but also the continuous and stable submerged arc operation greatly reduces the electrode wear and tear, reduces the accidental breakage of the electrode, further reduces energy consumption, reduces the energy cost of the enterprise, and thus improves the energy utilization efficiency.

[0045] Using Consteel electric furnaces to smelt high-titanium slag can significantly reduce the number of equipment such as distribution equipment, silos, charging equipment, electric furnace transformers, and plugging machines. At the same time, it simplifies the configuration of the hydraulic system, power distribution system, and SVC. It not only reduces the height of the plant, greatly saving construction investment, but also provides more space for equipment inspection and maintenance, making maintenance work more convenient and quick, reducing subsequent maintenance costs, and thus reducing economic consumption.

[0046] The electric furnace is charged by a spiral charging method, which helps to keep the furnace cover closed at all times, and the entire smelting system maintains negative pressure, effectively preventing the leakage of pollutants such as dust, making the working environment cleaner, greatly reducing labor intensity, improving workers' working conditions, and helping to improve workers' work efficiency and work enthusiasm.

[0047] During the smelting process, chemical reactions and physical conditions in the furnace cause the slag to foam and form a foamy slag layer. The Consteel arc is always in the molten pool, and the foamy slag forms a buffer layer around the arc, which can effectively absorb and block the propagation of noise generated by the arc, reducing the noise level of the entire smelting process, and helping to provide workers with a relatively quiet and comfortable working environment, thereby improving work efficiency.

[0048] In order to verify that the short-process technology for smelting high-titanium slag prepared in the embodiment of the present invention has good efficiency and environmental protection, the short-process technology for smelting high-titanium slag provided in the embodiment of the present invention is described through the following test examples.

[0049] Test example

[0050] The purpose of this experimental group is to explore the influence of different process parameters on the short-process technology for smelting high-titanium slag, and to detect the efficiency, environmental protection, stability and productivity of the short-process technology for smelting high-titanium slag of the present invention.

[0051] Test objectives: Test group A adopts the short process for smelting high-titanium slag provided in the embodiment; control group A and control group B are used as the control examples, wherein:

[0052] Control group A

[0053] Equipment Configuration: The furnace body has a large diameter, and to ensure uniform material distribution during charging, a large number of silos and complex material distribution equipment are required. For example, multiple silos of different specifications and functions are needed to store raw materials. The material distribution equipment includes various conveyor belts, distributors, etc., which are complex and numerous. The number of loading and feeding equipment also increases accordingly, including large bucket elevators, multiple feed belts, and discharge belts. The connection and coordination between these devices are relatively cumbersome. Due to the large number of equipment, the factory building height is generally 40m-50m to meet the space requirements for equipment installation and material transportation, which leads to huge construction investment.

[0054] Process flow: After the raw materials are prepared, they are transported to various silos through a complex loading system. During the loading process, the large number of equipment and long processes may cause segregation of the raw materials during transportation. The batching process is relatively dispersed, and different raw materials are weighed and batched in different areas. Then, the batched materials are added to the electric furnace through a complex distribution system. During this process, the uniformity of the materials is difficult to ensure, and uneven distribution is likely to occur, affecting the smelting effect.

[0055] Control group B

[0056] Power transmission and smelting: During the power transmission process, the electrodes come into direct contact with the mixed material. To avoid excessive electrode loss and other problems, the power supply is limited, and the maximum power input cannot be used from the beginning. This results in long smelting times, with single-furnace times far exceeding 60 minutes, low production capacity, and difficulty meeting the needs of efficient production. During the smelting process, the arc is unstable and prone to fluctuations, which makes the heat transfer efficiency between the arc and the molten pool low. A large amount of heat is radiated to the refractory material, furnace walls, and furnace cover water cooling plate, resulting in severe heat loss and increased energy consumption. Since the electrodes are in direct contact with the mixed material, they consume a lot of oxidation and are prone to accidental breakage, further increasing costs and maintenance workload.

[0057] Slag tapping and iron tapping: Slag tapping and iron tapping may require different discharge openings and operating procedures. The operation is relatively complicated, and the furnace workers need to perform heavy work such as drilling, burning, and plugging the slag and iron openings. The labor intensity is high, the working environment is harsh, there is a lot of dust, and the noise is high, which affects the workers' work efficiency and health.

[0058] Test method: Based on the high efficiency, environmental protection, stability and productivity of the short process for smelting high titanium slag, tests were conducted respectively. The specific test methods are as follows:

[0059] High efficiency test:

[0060] Smelting time record: In the experimental group A and the control groups A and B, the time from the start of power supply to the end of smelting for each heat was recorded, including the specific duration of each stage such as charging time, heating time, reduction time, slag and iron tapping time; the total smelting time of a single heat was compared between the experimental group A and the control groups A and B;

[0061] Capacity calculation and comparison: Based on the number of heats completed in the same period of time (such as one day, one week, etc.) for each group of experiments, and the amount of titanium slag and molten iron produced in each heat, the capacity of the experimental group A and the control groups A and B is calculated. If the capacity of the experimental group A is higher than that of the control group, it means that the process of the present invention is highly efficient in improving capacity. For example, the number of heats smelted by the experimental group A and the control group in one week and the average output of titanium slag and molten iron in each heat are counted, and the total weekly output is calculated for comparison.

[0062] Environmental testing:

[0063] Dust emission monitoring: Multiple dust monitoring points were set up around the electric furnaces and in the workshops of the experimental group A and the control groups A and B. Dust concentrations at different stages of the smelting process (charging, smelting, slag tapping, and iron tapping) were monitored in real time using dust detectors. The dust concentration data of the experimental group A was compared with those of the control groups A and B.

[0064] Gas recovery and utilization efficiency test: record the gas volume and gas composition discharged from the flue on the top of the electric furnace of the test group A and the control groups A and B, as well as the gas volume and quality recovered to the gas tank after treatment, and calculate the gas recovery rate and utilization rate.

[0065] Stability testing:

[0066] Temperature monitoring and analysis: Temperature sensors were installed at different locations in the electric furnaces of the experimental group A and the control groups A and B to monitor the temperature changes during the smelting process in real time, including the heating rate, the duration of different temperature stages, the temperature fluctuation range, etc. The temperature data of the experimental group A was compared with those of the control groups A and B;

[0067] Product quality testing: The titanium slag and molten iron produced by the experimental group A and the control groups A and B were subjected to quality testing, including the TiO2 content and impurity content in the titanium slag, the chemical composition and purity of the molten iron and other indicators.

[0068] Capacity rate detection:

[0069] Equipment operation time statistics: record the actual operation time and failure downtime of each major equipment (such as electric furnace, bucket elevator, screw feeder, cast iron machine, etc.) of the test group A and the control groups A and B within a certain period of time (such as one month), and calculate the equipment operation rate;

[0070] Energy consumption statistics and analysis: The energy consumption of experimental group A and control groups A and B at the same output, including electricity and fuel, is counted respectively, and the energy consumption index per unit product is calculated.

[0071] Specific detection indicators are shown in Tables 1-4.

[0072] Table 1 High efficiency test data

[0073] Experimental group A Control group A Control group B Total smelting time per single furnace (min) 55 70 80 Production capacity within one week (total amount of titanium slag + molten iron, t) 500 350 300

[0074] Table 2 Environmental testing data

[0075] Experimental group A Control group A Control group B <![CDATA[Average dust concentration (mg / m 3 , feeding stage)]]> 10 30 40 <![CDATA[Average dust concentration (mg / m 3 , smelting stage)]]> 8 25 35 <![CDATA[Average dust concentration (mg / m 3 , during slag discharging and iron tapping stages)]]> 12 35 45 Gas recovery rate (%) 90 70 60 Gas utilization rate (%) 85 65 55

[0076] Table 3 Stability test data

[0077]

[0078]

[0079] Table 4 Productivity test data

[0080] Experimental group A Control group A Control group B Equipment operation rate (%, one month) 95 85 80 Energy consumption per unit product (kWh / t) 300 350 400

[0081] According to Tables 1 to 4, the above comparative data are summarized as follows:

[0082] Efficiency

[0083] Smelting time: The total smelting time for a single heat in test group A was 55 minutes, significantly shorter than the 70 minutes in control group A and the 80 minutes in control group B. This indicates that the direct drop of the mixed material into the molten pool and the absence of direct contact of the electrodes with the mixed material during power transmission enable the input of electrical energy at maximum power and allow for short-term furnace shutdowns for slag or iron tapping, significantly shortening the smelting time and improving production efficiency.

[0084] Production capacity: The production capacity (total amount of titanium slag + molten iron) of the test group A within one week is 500t, while that of the control group A is 350t and that of the control group B is 300t. The production capacity of the test group A is much higher than that of the control group, indicating that the process of the present invention can produce more products in the same time and can better meet the needs of efficient production, thereby improving economic benefits.

[0085] Environmental protection

[0086] Dust emission: In the various stages of charging, smelting, slag tapping and iron tapping, the average dust concentration of test group A was lower than that of control group A and control group B. For example, in the charging stage, the average dust concentration of test group A was 10 mg / m 3 , control group A was 30 mg / m 3 , control group B was 40 mg / m 3The main feature of the present invention is that the electric furnace is charged by a spiral charging method, the furnace cover is always closed and the smelting system maintains a negative pressure, which effectively prevents dust leakage, improves the working environment, and is beneficial to workers' health and environmental protection.

[0087] Gas Recovery and Utilization: The gas recovery rate for test group A was 90% and the utilization rate was 85%, while the recovery rate for control group A was 70% and the utilization rate was 65%, and the recovery rate for control group B was 60% and the utilization rate was 55%. By effectively treating and recycling the gas generated in the sealed electric furnace, the process of the present invention improves energy utilization and reduces the environmental impact of gas emissions, thereby enhancing environmental performance and energy conservation.

[0088] Stability

[0089] Temperature control: The heating rate of test group A was 5°C / min, which was higher than 3°C / min of control group A and 2.5°C / min of control group B. The temperature fluctuation range was only ±10°C, which was much smaller than ±30°C of control group A and ±40°C of control group B. This shows that the process of the present invention, through precise temperature control and stable process conditions during the electric furnace smelting process, can enable the materials to react in a more stable temperature environment, which is conducive to improving product quality and production stability.

[0090] Product quality: The TiO2 content of the titanium slag produced by the experimental group A is 78%, which is higher than the 72% of the control group A and the 70% of the control group B. The purity of the molten iron is 98%, which is also higher than the 95% of the control group A and the 93% of the control group B. Stable process conditions and good temperature control are conducive to the production of high-quality titanium slag and molten iron.

[0091] Production capacity

[0092] Equipment operation rate: The one-month equipment operation rate of test group A was 95%, higher than the 85% of control group A and the 80% of control group B. This was mainly due to the more reasonable configuration of the Consteel electric furnace and related equipment, which made the equipment operation more stable and reliable, reduced downtime, and improved the overall operation efficiency of the equipment.

[0093] Energy consumption: The unit product energy consumption of test group A was 300kWh / t, lower than the 350kWh / t of control group A and the 400kWh / t of control group B. This was mainly achieved through continuous feeding, continuous smelting, stable arc and coverage by foam slag, which reduced heat loss, electrode oxidation consumption and accidental breakage, thereby achieving energy conservation and consumption reduction, and lowering the company's production costs.

[0094] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A short process for smelting high titanium slag based on Consteel electric furnace, characterized in that: The following steps are involved: S1. Raw material preparation: high-grade titanium concentrate and reducing agent; S2. Raw material loading: high-grade titanium concentrate and reducing agent are poured into the loading silo, and the raw materials are lifted to the upper surface of the loading belt by a bucket elevator. At the same time, the high-grade titanium concentrate is fed into the titanium ore bin and the reducing agent is fed into the reducing agent bin by a plow discharger. Then, the high-grade titanium concentrate and reducing agent are respectively added to the weighing hopper through the feeding belt for weighing and batching. The weighed raw materials are discharged to the mixing belt through two discharge belts for mixing. The mixed raw materials are discharged into the interior of the three batching bins through the plow discharger. Finally, the raw materials in the three batching bins are evenly fed into the electric furnace through three screw feeders. S3. Electric furnace smelting: In the electric furnace, electric energy is transmitted to the furnace through the water-cooled conductive cross arm of the copper-steel composite plate. The electric furnace electrode at the end of the electric energy transmission leads the electric energy into the furnace for melting and smelting; During the heating process, the mixed material undergoes deep reduction to produce slag and iron separation. At the same time, the reduction process in the closed electric furnace produces a large amount of high-temperature coal gas. S4, slag discharge operation: When slag is discharged, the electric furnace is tilted, and the titanium slag is discharged from the electric furnace outlet and collected into a slag bag. The slag bag is transported to the slag cooling room by a slag bag car for cooling, crushing, and screening to obtain titanium slag with a TiO2 content of more than 75%; S5. Tapping operation: Controls the number of times the smelting furnace is turned on. Tapping is performed after the last slag tapping. The furnace is tilted during tapping. Molten iron is discharged from the same outlet of the furnace and then transferred to a ladle. The ladle is transported by a ladle car to the cast iron machine for casting ingots. The ingots are cast on the cast iron machine and used as raw materials in the steel plant. S6. Gas treatment: The high-temperature gas discharged from the flue on the top of the electric furnace is cooled by a water-cooled flue, and then the dust in the gas is removed by gravity dust removal and a high-temperature metal film fine dust collector. The gas is then cooled by air and then transported to a gas tank for temporary storage before being delivered to the user.

2. The short process for smelting high titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In the S1, the amount of high-grade titanium concentrate is 85%-90%; the amount of reducing agent is 10%-15%.

3. The short process for smelting high titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In the S1, the total amount of ilmenite in the high-grade ilmenite concentrate is greater than 90%, and the grade is greater than 44%.

4. The short-process method for smelting high-titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In S2, materials are continuously fed into the electric furnace at a uniform speed through three screw feeders, gas sealing devices are provided under the three screw feeders, and the total feeding amount of the three screw feeders per hour is controlled at 40t, and the smelting time of a single furnace is controlled at 1h.

5. The short process for smelting high titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In S3, electric energy is transmitted to the electric furnace for melting and smelting through a water-cooled conductive cross arm of a copper-steel composite plate. The transformer used has a rated power of 45MVA+10% continuous overload, a primary voltage of 35KV, and a frequency of 50Hz. The electrode diameter is 550mm, the pole center circle diameter is 1100mm, and the electrode lifting is automatically controlled by constant current.

6. The short process for smelting high titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In the S3, the electric furnace electrodes are sealed using a three-stage "ring brick + nitrogen + filler" method, and the furnace cover and furnace body are also sealed.

7. The short process for smelting high titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In the S3, the electric furnace adopts eccentric bottom tapping for slag or iron, the inner diameter of the lower furnace shell of the electric furnace is 5600mm; the total capacity is 115t and the nominal capacity is 75t.

8. The short-process method for smelting high-titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In the S3, during the electric furnace smelting process, when the temperature is greater than 850°C, FeO in the mixture begins to be solid-phase reduced; when the temperature reaches above 1300°C, deep reduction of FeO and other oxides is carried out; the material after deep reduction is gradually melted during the continuous heating process, and during the melting process of the material, the high-temperature molten iron and the slag liquid are separated due to the difference in density, and titanium slag is obtained at the upper part of the molten pool, and molten iron is obtained at the bottom of the molten pool.

9. The short-flow process for smelting high-titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In said S5, the number of times of smelting furnace is controlled to be 3-4 times, and the amount of molten iron is controlled to be 45t-50t.

10. The short-flow process for smelting high-titanium slag based on Consteel electric furnace according to claim 1, characterized in that: In the above-mentioned S6, the temperature of the high-temperature coal gas is 900° C.-1000° C., which is cooled to 500° C.-600° C. by water-cooling flue and to below 50° C. by air cooling.

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