Tundish covering agent preparation system and application

Abstract

The invention provides a tundish covering agent preparation system and application, the tundish covering agent preparation system comprises a mineral raw material pretreatment unit, a mineral particle matching unit, a mineral particle mixture drying unit and a product packaging and warehousing unit, and all the units are conveyed through a conveyor and fed through a feeder; the mineral raw material pretreatment unit is used for processing mineral raw materials into mineral raw material granules with different size fractions and conveying the mineral raw material granules to the mineral granule matching unit; the mineral particle matching unit is used for matching and uniformly mixing mineral particles obtained by the mineral raw material pretreatment unit to obtain a mineral particle mixture and conveying the mineral particle mixture to the mineral particle mixture drying unit; the mineral particle mixture drying unit is used for drying the mineral particle mixture obtained by the mineral particle matching unit to obtain a tundish covering agent and conveying the tundish covering agent to the product packaging and warehousing unit; and the product packaging and warehousing unit is used for weighing and packaging the products. The system is simple in structure, low in production energy consumption, high in efficiency and high in raw material pretreatment controllability, and can be used for production of various tundish covering agents.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical fields of mineral processing and metallurgical auxiliary materials, in particular to a tundish covering agent preparation system and application. BACKGROUND

[0002] The measures of heat preservation, dephosphorization and secondary oxidation prevention of molten steel in ladle are related to tapping temperature system, smooth casting and quality of casting billet, and thus are focused on by continuous casting workers. With the continuous expansion of continuous casting production scale and the development of continuous casting process, the capacity of the ladle is increased, and the residence time of molten steel in the ladle is correspondingly prolonged. In order to meet the process requirements of subsequent processes, improve the cleanliness of molten steel, prevent secondary oxidation of molten steel, reduce temperature drop, and provide molten steel with appropriate temperature in the continuous casting process to ensure smooth casting, a certain amount of tundish covering agent must be added on the surface of molten steel after the molten steel is introduced into the tundish for heat preservation.

[0003] However, the traditional tundish covering agent is simple in raw materials, and is mostly single carbonized rice husk or perlite. The preparation method is often only crushing treatment. The simplicity of raw materials and the extensive control of particle size not only cannot meet the requirements of the development of continuous casting production, but also leads to the decline of product performance in the continuous casting process. For example, poor deslagging performance leads to the decline of casting strength and toughness, and the reduction of plasticity. In order to solve these problems, researchers begin to use multiple raw materials and deep processing of raw materials in the preparation of tundish covering agent. For example, alkali raw materials are used and the raw materials are melted and then ground and granulated. These methods improve the deslagging effect and particle size control of tundish covering agent to a certain extent, but they also bring new problems. For example, too much attention is paid to the improvement of alkalinity, which leads to the deterioration of heat preservation performance of tundish covering agent, the high cost of raw materials for increasing alkalinity, the use of artificial synthetic adhesive in melting and granulation, the additional energy consumption in pre-melting of raw materials, and the high cost of preparation of tundish covering agent.

[0004] Therefore, based on the development needs of tundish covering agent, it is of great significance to innovate a new tundish covering agent preparation system, select appropriate processing equipment and processing process according to the properties of raw materials, and strictly control the particle size of raw materials, so as to obtain a new tundish covering agent preparation system with simple preparation process, low production cost and the functions of heat preservation, deslagging and secondary oxidation prevention. SUMMARY

[0005] The present application relates to the technical fields of mineral processing and metallurgical auxiliary materials, in particular to a tundish covering agent preparation system and application.

[0006] To achieve the above object, the present application provides a kind of intermediate package covering agent preparation system, the system includes mineral raw material preprocessing unit, mineral particle matching unit, mineral particle mixture drying unit and product packing storage unit, each unit is conveyed by conveyor, wherein:

[0007] The mineral raw material preprocessing unit includes mineral raw material storage, crushing mechanism, screening mechanism and mineral particle material storage, and can process mineral raw material into different particle size mineral raw material particles;

[0008] The mineral particle matching unit includes feeder, mixer and mineral particle mixture storage, and can match and mix the mineral particle material obtained from the mineral raw material preprocessing unit to obtain mineral particle mixture;

[0009] The mineral particle mixture drying unit includes drying kiln, and can dry the mineral particle mixture obtained from the mineral particle matching unit to obtain intermediate package covering agent;

[0010] The product packing storage unit includes weighing and packing mechanism and product storage, and can weigh and pack the product, and a conveyor is arranged between the weighing and packing mechanism and the product storage.

[0011] Optionally, at least one of the mineral raw material preprocessing unit, the mineral particle matching unit, the mineral particle mixture drying unit and the product packing storage unit is fed by a feeder.

[0012] Optionally, the mineral raw material storage includes base material mineral storage, swelling mineral auxiliary material storage, viscosity adjusting mineral storage and melting point adjusting mineral storage;The base material mineral storage, swelling mineral auxiliary material storage, viscosity adjusting mineral storage and melting point adjusting mineral storage are all composed of multiple secondary storages, for storing different types of mineral raw materials.

[0013] Optionally, the crushing mechanism includes coarse crushing section, medium crushing section, fine crushing section and ultrafine crushing section connected by belt conveyor, the coarse crushing section includes at least one of jaw crusher and roller crusher;The medium crushing section includes at least one of roller crusher and cone crusher;The fine crushing section includes at least one of impact crusher or cone crusher;The ultrafine crushing section includes at least one of roller crusher, high pressure roller mill, ball mill and autogenous mill.

[0014] Optionally, the screening mechanism includes at least one of graded inertial vibrating screen and graded rolling screen.

[0015] Optionally, the conveyor can include belt conveyor, specifically at least one of fixed belt conveyor, telescopic belt conveyor and reversing belt conveyor.

[0016] Optionally, the mineral particle material storage bin is used for storing different types of mineral particle materials, and the mineral particle material storage bin is provided with a plurality of secondary storage bins used for storing mineral particle materials of different categories and particle sizes; the bottom of each secondary storage bin is provided with a screw feeder or a gate for controlling the discharging speed.

[0017] Optionally, the conveying machine is used for conveying materials between the mixer and the mineral particle mixture storage bin; the mixer comprises at least one of a screw belt mixer, a paddle mixer, a planetary power mixer and a V-type mixer.

[0018] Optionally, the mineral particle mixture storage bin is used for storing mineral particle mixtures of different types or proportions of intermediate covering agents; the mineral particle mixture storage bin is a temporary storage bin with a screw feeder.

[0019] Optionally, the proportioning is automatically weighed and proportioned by a PLC / DCS control system, which can weigh and quantitatively convey mineral particle materials of different categories and particle sizes; the PLC / DCS system is connected to the feeder and the mixer for controlling the feeding amount, mixing time, stirring speed and feeding / discharging sequence, and realizing automatic operation.

[0020] Optionally, the drying kiln comprises at least one of an electric heating rotary kiln, a fuel gas rotary kiln and a fuel oil rotary kiln.

[0021] Optionally, the temperature of the kiln body of the electric heating rotary kiln ranges from 100 to 300℃ from the inlet to the outlet, the length of the kiln body is 10-30m, the temperature gradient is 10-30℃ / m, and the drying time of the material is 10-30min; the temperature of the kiln body of the fuel gas rotary kiln and the fuel oil rotary kiln ranges from 150 to 300℃ from the inlet to the outlet, the length of the kiln body is 10-20m, the temperature gradient is 6-15℃ / m, and the pre-drying time of the material is 3-30min.

[0022] Optionally, the mineral particle mixture drying unit further comprises a cooling bin.

[0023] Optionally, the moisture content of the intermediate covering agent is less than or equal to 1%, and the water is adsorbed water.

[0024] Optionally, the weighing and packaging mechanism can automatically control the metering, loading and packaging of the product, and the weighing and packaging mechanism comprises at least one of an open packaging machine and a ton bag packaging machine.

[0025] Optionally, the product storage bin comprises an alkaline intermediate covering agent storage bin, an acidic intermediate covering agent storage bin, a high-magnesium component intermediate covering agent storage bin and a high-temperature viscosity controllable intermediate covering agent storage bin.

[0026] Optionally, the intermediate covering agent preparation system further comprises a dust removal unit, and dust suction ports of the dust removal unit are respectively arranged at the crushing mechanism, the screening mechanism and the product packaging and storage unit; the dust suction ports are connected with a bag dust collector through pipelines.

[0027] Optionally, the mineral raw materials include calcium-based mineral raw materials, siliceous mineral raw materials, magnesium-rich mineral raw materials, expandable mineral raw materials, viscosity-adjusting mineral raw materials and melting point-adjusting mineral raw materials.

[0028] Optionally, the calcium-based mineral raw materials include at least one of quicklime, wollastonite and calcined dolomite; the siliceous mineral raw materials include at least one of quartz ore, diatomite or zeolite with high silicon content, and the quartz ore includes at least one of vein quartz, natural quartz sand, white granite and quartzite; the magnesium-rich mineral raw materials include at least one of serpentine, peridotite, periclase ore, brucite, talc and calcined dolomite; the expandable mineral raw materials include at least one of perlite, obsidian, pine tar rock, pumice-like perlite and vermiculite; and the viscosity-adjusting mineral raw materials and the melting point-adjusting mineral raw materials include serpentine, periclase, quartz ore, potassium feldspar, sodium feldspar and feldspar derivatives, and the derivatives include at least one of sanidine, microcline, bytownite and labradorite.

[0029] Another aspect of the present application provides an application of the intermediate covering agent preparation system, which is the above-mentioned system.

[0030] Optionally, the application includes using the intermediate covering agent preparation system to prepare high-magnesium component intermediate covering agents, alkaline intermediate covering agents, acidic intermediate covering agents and high-temperature viscosity-controllable intermediate covering agents.

[0031] Compared with the prior art, the present application has the following beneficial effects at least one of which is included:

[0032] (1) The intermediate covering agent preparation system has strong controllability of each unit, simple preparation process, low energy consumption, high production efficiency, and can avoid dust diffusion and raw material waste in the production process;

[0033] (2) The intermediate covering agent preparation system has high automation degree, compact structure, smooth process flow, and can save production space;

[0034] (3) The intermediate covering agent preparation system can realize automatic weighing and proportioning of different types of materials, controllable particle size, and preparation and production of a series of multifunctional intermediate covering agents according to design requirements;

[0035] (4) The intermediate ladle covering agent preparation system of the present application has no three waste emissions in the production process, and meets the technical requirements of green production;

[0036] (5) The intermediate ladle covering agent preparation system of the present application does not add fluorine-containing substances and phosphorus and sulfur-containing raw materials in the application process, and the produced intermediate ladle covering agent does not affect the quality of steel in the use process, and does not produce substances harmful to the environment and human body. BRIEF DESCRIPTION OF DRAWINGS

[0037] The above and other objects and / or characteristics of the present application will become more apparent by describing in detail one embodiment of an intermediate ladle covering agent preparation system and application of the present application with reference to the attached drawings, in which:

[0038] Figure 1 A simple flowchart of the composition of the intermediate ladle covering agent preparation system of the present application is shown;

[0039] Figure 2 The spreading and covering effect diagram of the intermediate ladle covering agent prepared in Example 1 of the present application on the steel liquid surface is shown;

[0040] Figure 3 The spreading and covering effect diagram of the intermediate ladle covering agent prepared in Example 2 of the present application on the steel liquid surface is shown;

[0041] Figure 4 The spreading and covering effect diagram of the intermediate ladle covering agent prepared in Example 3 of the present application on the steel liquid surface is shown;

[0042] Figure 5 The spreading and covering effect diagram of the intermediate ladle covering agent prepared in Example 4 of the present application on the steel liquid surface is shown;

[0043] Figure 6 The slagging and morphology effect diagram of the intermediate ladle covering agent prepared in Example 1 of the present application after use is shown;

[0044] Figure 7 The slagging and morphology effect diagram of the intermediate ladle covering agent prepared in Example 2 of the present application after use is shown;

[0045] Figure 8 The slagging and morphology effect diagram of the intermediate ladle covering agent prepared in Example 3 of the present application after use is shown;

[0046] Figure 9 The slagging and morphology effect diagram of the intermediate ladle covering agent prepared in Example 4 of the present application after use is shown. DETAILED DESCRIPTION

[0047] Hereinafter, an intermediate ladle covering agent preparation system and application of the present application will be described in detail in conjunction with exemplary embodiments.

[0048] Example Embodiment 1

[0049] The present example embodiment provides a kind of intermediate package covering agent preparation system, as Figure 1 The simple flow schematic diagram of the system composition shown in the figure, the system can include mineral raw material preprocessing unit, mineral particle matching unit, mineral particle mixture drying unit and product packing storage unit, conveying between each unit by conveyor, by feeder feeding.

[0050] The mineral raw material preprocessing unit can include mineral raw material storage, crushing mechanism, screening mechanism and mineral particle material storage, can be processed into different particle size mineral raw material particle material, conveyor can be conveyed to mineral particle matching unit;

[0051] The mineral particle matching unit can include feeder, mixer and mineral particle mixture storage, can be matched and mixed evenly to obtain mineral particle mixture by mineral particle material obtained from mineral raw material preprocessing unit, conveyor can be conveyed to mineral particle mixture drying unit;

[0052] The mineral particle mixture drying unit can include drying kiln and cooling bin, can be dried to obtain intermediate package covering agent by mineral particle mixture obtained from mineral particle matching unit, conveyor can be conveyed to product packing storage unit;

[0053] The product packing storage unit can include weighing and packing mechanism and product storage, can be weighed and packed, weighing and packing mechanism and storage are connected by conveyor.

[0054] In the present embodiment, the mineral raw material storage can include base material mineral storage, expandable mineral auxiliary material storage and viscosity adjusting mineral storage and melting point adjusting mineral storage;The base material mineral storage, expandable mineral auxiliary material storage and viscosity adjusting mineral storage and melting point adjusting mineral storage are all composed of multiple secondary storages, for storing different types of mineral raw materials.

[0055] In the present embodiment, the crushing mechanism can include coarse crushing section, medium crushing section, fine crushing section and ultrafine crushing section connected by belt conveyor, the coarse crushing section can include at least one of jaw crusher and roller crusher;The medium crushing section can include at least one of roller crusher and cone crusher;The fine crushing section can include at least one of impact crusher or cone crusher;The ultrafine crushing section can include at least one of roller crusher, high pressure roller mill, ball mill and autogenous mill.

[0056] In the present embodiment, the screening mechanism can include at least one of classification inertia vibrating screen and classification rolling screen.

[0057] In the present embodiment, the conveyor can include a belt conveyor, such as at least one of a fixed belt conveyor, a retractable belt conveyor, and a turning belt conveyor.

[0058] In the present embodiment, the crushing mechanism and the screening mechanism can be a complete crushing and screening process with inspection screening, which is composed of a three-stage closed-circuit crushing with pre-inspection screening and closed-circuit screening.

[0059] The three-stage closed-circuit crushing with pre-inspection screening includes coarse crushing, medium crushing, and fine crushing. The coarse crushing is a primary particle material with a particle size of >10 mm after the raw ore is crushed by a bar screen, and a jaw crusher can be selected. The medium crushing is a secondary particle obtained by crushing the primary particle material after the coarse crushing, and a jaw crusher and a cone crusher can be selected. The fine crushing is a tertiary particle material obtained by crushing the secondary particle material after the medium crushing, and a jaw crusher, a cone crusher, an impact crusher, and a roller crusher can be selected. The crushing product after the three-stage closed-circuit crushing with pre-inspection screening is a fourth particle material with a particle size of ≤10 mm, of which the particle material with a particle size of >10 mm is returned to the medium crushing stage. The screening refers to multi-layer screening, and the screening equipment can be selected, such as fixed rod bar screens, arc-shaped bar screen, and vibrating rod bar screens.

[0060] The closed-circuit screening refers to crushing and screening the fourth particle material, and the crushing is superfine crushing, which can be selected from a roller crusher, a high-pressure roller mill, a ball mill, and a autogenous mill. The particle material after the crushing is subjected to two-stage screening, and according to the need, the particle material with a particle size of >20 mesh after the first-stage screening is returned to the crushing stage, the particle material with a particle size of ≤20 mesh is subjected to the second-stage screening to obtain the target particle material, and the particle material that does not meet the requirements is processed separately. The screening equipment can be selected from multi-layer revolving screens and reciprocating vibrating screens. The screen mesh can be provided with 10 mesh, 20 mesh, 30 mesh, 50 mesh, 70 mesh, 90 mesh, 100 mesh, 150 mesh, and 200 mesh, and different particle sizes of mineral raw material particles can be obtained according to the preparation requirements of the intermediate covering agent.

[0061] In the present embodiment, the mineral particle material storage bin is used to store different types of mineral particle materials, and the mineral particle material storage bin is provided with a plurality of secondary storage bins for storing mineral particle materials of different categories and particle sizes. The bottom of the secondary storage bin is provided with a screw feeder or a gate for controlling the discharging speed.

[0062] In the embodiment, a conveyor is arranged between the mixer and the mineral particle mixture storage bin; the mixer comprises at least one of a ribbon mixer, a paddle mixer, a planetary dynamic mixer and a V-shaped mixer. The mineral raw material particles in the mineral raw material particle storage bin are accurately fed by a screw feeder, and are conveyed to the mixer by a belt conveyor. The screw feeder is accurately fed by adopting a control layer division architecture on the control of the screw feeder, that is, a production process monitoring system with DCS as the core is constructed, the screw feeder unit is independently controlled by a local intelligent controller (PLC), and data integration is performed with the D system through an industrial network. The high accuracy and high reliability of the feeding process are ensured, and the centralized, digitized and intelligent needs of production management are met. The specific operation is that an operator inputs the total production amount such as 100 kg / h on the DCS operator station, and the DCS automatically calculates the target set flow of each feeder according to the given ratio. The feeding should have a fixed feeding sequence, such as adding a part of the base raw material with a large proportion first, mixing for a period of time, then adding auxiliary materials with a small proportion, and then adding the remaining base raw material. In addition, the stirring speed is divided into three stages, the first stage is a low speed stage (25-30 rpm), which belongs to the feeding stage. When feeding, low speed running can reduce dust flying, prevent material loss and environmental pollution, and also reduce the starting load. The second stage is a high speed stage (45-75 rpm), which belongs to the mixing stage. After all the materials are added, the speed is switched to high speed to achieve the best mixing strength, so that the material quickly reaches the initial uniform state. The third stage is a low speed stage (30-50 rpm), which belongs to the homogenization and cooling stage. After high-speed mixing for a period of time, the speed is switched to low speed for continuous mixing, which can continue to promote homogenization. The three different speed stages correspond to different stirring times. When all the raw materials are added, enter the high speed stage, start a timer, and start mixing time T1 (here, according to the particle size level of the raw material, it can be 10 min, 15 min, 20 min). After the high speed stage timer reaches the point, the DSC adjusts the speed to the low speed stage, and starts a second timer at this time, with a timing time of T2 (here, according to the particle size level of the raw material, it can be 2 min, 5 min, 10 min). After the second timer reaches the point, the DCS controls the mixer to stop, and the mixed mineral particle mixture is conveyed to the mineral particle mixture storage bin by the conveying pipeline or the belt conveyor. After the above operation, the system is reset, and the next cycle is performed.

[0063] In the embodiment, the mineral particle mixture storage bin is used for storing mineral particle mixtures of different types or ratios of intermediate coating agents; and the mineral particle mixture storage bin is a temporary storage bin with a screw feeder.

[0064] In this embodiment, the proportioning is automated by using a PLC / DCS control system for weighing and proportioning, which can weigh and quantitatively convey mineral particles of different types and sizes. The PLC / DCS system is connected to the feeder and the mixer to control the amount of material fed, the mixing time, the stirring speed and the feeding / discharging sequence, and to realize automated operation.

[0065] For example, before the granular material is mixed, the system uses a screw feeder and a DCS control system to achieve automated proportioning, which can precisely control the mineral composition ratio of the high-magnesium component intermediate bag covering agent, the alkaline intermediate bag covering agent, the acidic intermediate bag covering agent, and the high-temperature viscosity controllable intermediate bag covering agent. The high-magnesium component intermediate bag covering agent can have a mineral composition ratio of 50-70 parts magnesium-rich minerals, 5-15 parts calcium-based minerals, 5-15 parts expandable minerals, and 5-20 parts viscosity-regulating minerals; the alkaline... The mineral composition ratio of the intermediate tundish can be 40-60 parts calcium-based minerals, 20-60 parts expandable minerals, 5-20 parts viscosity-regulating minerals, and 5-30 parts melting point-regulating minerals; the mineral composition ratio of the acidic intermediate tundish covering agent can be 50-80 parts silicate minerals, 5-20 parts expandable minerals, and 5-20 parts viscosity-regulating minerals; the mineral composition ratio of the high-temperature viscosity-controllable intermediate tundish covering agent can be 20-50 parts by weight of quicklime, 5-40 parts by weight of perlite, 5-30 parts by weight of quartz sand, and 5-30 parts by weight of feldspar minerals.

[0066] In this embodiment, the drying kiln includes at least one of an electrically heated rotary kiln, a gas-fired rotary kiln, and an oil-fired rotary kiln.

[0067] In this embodiment, the temperature range from the inlet to the outlet of the electrically heated rotary kiln is 100–300°C, the kiln length is 10–30 m, the temperature gradient is 10–30°C / m, and the material drying time is 10–30 min. The inlet (which is also the exhaust outlet) of the kiln is connected to the belt conveyor of the mineral particle mixture unit, and the outlet is the air inlet and directly connected to the belt conveyor. The gas entering through the air inlet can be air, and the outlet can be equipped with an induced draft fan to expel air containing water vapor. The air flows from the high-temperature end to the low-temperature end of the rotary kiln.

[0068] In the embodiment, the temperature range of the inlet to the outlet of the kiln body of the gas-fired rotary kiln and the oil-fired rotary kiln is 150-300℃, the length of the kiln body is 10-20m, the temperature gradient is 6-15℃ / m, and the pre-drying time of the material is 3-30min. The inlet of the kiln body (also the exhaust port) is connected with the mineral particle mixture unit belt conveyor, the outlet is the air inlet and directly communicates with the belt conveyor; the gas entering the air inlet of the kiln body can be hot air generated by gas or oil, the exhaust port can be provided with an induced draft fan to discharge the air containing water vapor, and the air flows from the high-temperature end to the low-temperature end of the rotary kiln body.

[0069] The electric heating rotary kiln, the gas-fired rotary kiln and the oil-fired rotary kiln all include a pre-drying kiln body and a drying kiln body, the temperature range of the inlet to the outlet of the pre-drying kiln body is 20-90℃, and the temperature gradient is 6-15℃ / m; the temperature range of the drying kiln body from the inlet to the pre-heating section of the kiln body is 100-300℃, the temperature gradient is 30-40℃ / m, the length of the kiln body is 10-30m, and the drying time is 10-30min; the inlet of the drying kiln body is also connected with the mineral particle mixture unit belt conveyor, the outlet is the air inlet and directly communicates with the belt conveyor, the gas entering the air inlet can be air, the exhaust port can be provided with an induced draft fan to discharge the air containing water vapor, and the air flows from the high-temperature end to the low-temperature end of the rotary kiln body.

[0070] In the embodiment, the mineral particle mixture drying unit can further include a hot air generator, and the hot air generator includes at least one of a hot air circulating type hot air generator, a high-pressure type hot air generator and an explosion-proof type hot air generator.

[0071] In the embodiment, the moisture of the intermediate coating agent is ≤1%, the moisture is adsorbed water, and the dried intermediate coating agent is conveyed to the cooling bin by the belt conveyor and placed for 2-3 hours for cooling treatment.

[0072] In the embodiment, the weighing and packaging mechanism can automatically control the metering, charging and packaging of the product, and the weighing and packaging mechanism includes at least one of an open packaging machine and a ton bag packaging machine.

[0073] In the embodiment, the product storage includes a basic intermediate ladle covering agent storage, an acidic intermediate ladle covering agent storage, a high magnesium component intermediate ladle covering agent storage, and a high temperature viscosity controllable intermediate ladle covering agent storage. Different kinds and different particle size specifications of granular materials obtained by the previous step can be respectively received, wherein the particle size specifications of various mineral raw materials of the basic intermediate ladle covering agent are as follows: the calcium-based mineral, the expandable mineral, the viscosity adjusting mineral, and the melting point adjusting mineral are-60~+100 mesh, -20~+80 mesh, -100~+200 mesh, and -100~+200 mesh respectively; the particle size specifications of the acidic covering agent are as follows: the siliceous mineral, the expandable mineral, and the viscosity adjusting mineral are-70~+100 mesh, -20~+80 mesh, and -90~+200 mesh respectively; the particle size specifications of various mineral raw materials of the high temperature viscosity controllable covering agent are as follows: the quicklime, the perlite mineral, the quartz mineral, and the feldspar mineral are-60~+100 mesh, -20~+60 mesh, -100~+150 mesh, and -60~+100 mesh respectively; the particle size specifications of various mineral raw materials of the high magnesium component intermediate ladle covering agent are as follows: the magnesium-rich mineral, the calcium-based mineral, the expandable mineral, and the viscosity adjusting mineral are-60~+100 mesh, -50~+150 mesh, -20~+80 mesh, and -70~+200 mesh respectively.

[0074] In the embodiment, the different mineral raw materials are processed to different particle size specifications so that the base mineral raw materials and the different auxiliary mineral raw materials maintain appropriate particle sizes, facilitating the accelerated melting of the covering agent and the balanced fluxing speed, so that a suitable molten layer can be formed in a short time.

[0075] In the embodiment, the intermediate ladle covering agent preparation system further includes a dust removal unit, and dust suction ports of the dust removal unit are respectively arranged at the crushing mechanism, the screening mechanism, and the product packaging and storage unit; the dust suction ports are connected with a bag dust collector through pipelines. The dust removal is to purify the air in the workshop and collect the dust generated in the crushing and screening processes of the mineral raw materials. The powder exceeding the target particle size obtained in the screening process is tailing-removed together with the dust collected by the bag dust collector.

[0076] In the embodiment, the mineral raw materials include calcium-based mineral raw materials, siliceous mineral raw materials, magnesium-rich mineral raw materials, expandable mineral raw materials, viscosity adjusting mineral raw materials, and melting point adjusting mineral raw materials.

[0077] In the embodiment, the calcium-based mineral raw material includes at least one of quicklime, wollastonite, and calcined dolomite; the siliceous mineral raw material includes at least one of quartz ore, diatomite, or zeolite with high silicon content, and the quartz ore includes at least one of vein quartz, natural quartz sand, white granite, and quartzite; the magnesium-rich mineral raw material includes at least one of serpentine, peridotite, magnesite, brucite, talc, and calcined dolomite; the expandable mineral raw material includes at least one of perlite, obsidian, pitchstone, pumice-like perlite, and vermiculite; and the viscosity-adjusting mineral raw material and the melting point-adjusting mineral raw material include serpentine, periclase, quartz ore, potassium feldspar, sodium feldspar, and feldspar derivatives, and the derivatives include at least one of sanidine, microcline, bytownite, and labradorite.

[0078] Example 2

[0079] The example provides an application of an intermediate ladle covering agent preparation system.

[0080] In the embodiment, the application includes preparation of high-magnesium component intermediate ladle covering agent, alkaline intermediate ladle covering agent, acidic intermediate ladle covering agent, and high-temperature viscosity-controllable intermediate ladle covering agent by using the intermediate ladle covering agent preparation system.

[0081] In order to better understand the above-mentioned example of the present application, the following further describes the example with specific examples.

[0082] Example 1

[0083] The example uses the intermediate ladle covering agent preparation system in Example 1 to prepare an acidic intermediate ladle covering agent.

[0084] First, natural quartz sand is selected as the base material of the acidic intermediate ladle covering agent, perlite is selected as the expandable mineral, and vermiculite and potassium feldspar are selected as the viscosity and melting point adjusting minerals. Then, the natural quartz sand, perlite, vermiculite, and potassium feldspar are subjected to controlled crushing, screening, and dust removal to obtain mineral raw material granules. In the system, the crusher is selected to be a jaw crusher, a roller crusher, and a cone crusher, and the granules are screened by using a hierarchical inertial vibrating screen and a hierarchical rolling screen at the stages of coarse crushing, medium crushing, fine crushing, and ultra-fine crushing, and the dust in the workshop is collected by using a bag dust collector. The jaw crusher is selected for coarse crushing, the roller crusher is selected for medium crushing, the cone crusher is selected for fine crushing, and the autogenous mill is selected for ultra-fine crushing, to obtain mineral raw material granules with particle sizes of -70+90 mesh, -30+50 mesh, -70+80 mesh, and -100+150 mesh, respectively.

[0085] The acidic intermediate ladle covering agent formula is that the mineral raw material granules are proportioned according to the mass fraction ratio, and then the DCS control system in the system issues a command to the mixer to set natural quartz sand, perlite, vermiculite and potassium feldspar = 70:10:10:10. When the total production of the batch is 100 kg, the natural quartz sand set value is calculated as 100 x (70 / 100) = 70 kg / h, the perlite set value is 100 x (10 / 100) = 10 kg / h, the vermiculite set value is 100 x (10 / 100) = 10 kg / h, and the potassium feldspar set value is 100 x (10 / 100) = 10 kg / h. After the screw feeder in the system receives the command, the corresponding weight of the mineral raw material granules is added first and low-speed stirring is carried out, the stirring speed is 27 rpm. After the feeding is completed, the low-speed stirring is ended and enters the high-speed stirring stage, the stirring speed is 60 rpm, and the stirring time is 15 min. Finally, it enters the medium-low speed stirring stage, the stirring speed is 40 rpm, and the stirring time is 5 min.

[0086] The mixed mineral granules obtained are transported by a belt conveyor to the fuel-fired rotary kiln in the system for drying, the drying section length is 15 m, the temperature rising rate is 6 ℃ / min, the drying temperature is 150 ℃, and the drying time is 30 min. In order to control the water content of the covering agent to be less than 1%, so as to obtain the MgO-Al2O3-SiO2 ternary component acidic intermediate ladle covering agent product, the melting point of the intermediate ladle covering agent is 1340 ℃, and the viscosity is 0.22 Pa.s. The prepared MgO-Al2O3-SiO2 ternary component acidic intermediate ladle covering agent is sealed in a bag by using a ton bag packaging machine.

[0087] The MgO-Al2O3-SiO2 ternary component acidic intermediate ladle covering agent obtained above is subjected to molten steel liquid level covering experiment, the prepared intermediate covering agent is added to the steel liquid surface (the steel type is 45 steel) at a usage amount of 2 kg per square meter, the intermediate covering agent rapidly expands and spreads to completely cover the steel liquid surface, and maintains a good covering layer, the specific effect is as shown in Figure 2 The intermediate ladle covering agent can cover the steel liquid surface, and the effective covering time is within 180 s. After working on the 1500 ℃ steel liquid surface, it is salvaged, and the appearance effect is as shown in Figure 6 The molten slag is complete and does not appear to be broken.

[0088] Example 2

[0089] In this example, the intermediate ladle covering agent prepared by the system in Example 2 is used to prepare an alkaline intermediate ladle covering agent.

[0090] Firstly, the wollastonite is selected as the alkaline adjusting mineral of the alkaline tundish covering agent, the obsidian is selected as the expandable mineral, the vein quartz, the white marble and the serpentine are selected as the viscosity adjusting mineral and the melting point adjusting mineral, then the wollastonite, the obsidian, the vein quartz, the white marble and the serpentine are controlled to be crushed, sieved and dedusted to obtain the mineral raw material granules, wherein the crusher in the system is selected to be the jaw crusher, the roller crusher and the cone crusher, and the granules are sieved by the classified inertial vibrating screen and the classified rolling screen in the coarse crushing, the medium crushing, the fine crushing and the ultrafine crushing stages, and the dust in the workshop is collected by the bag dust collector. The jaw crusher is selected to be used for the coarse crushing, the roller crusher is selected to be used for the medium crushing, the cone crusher is selected to be used for the fine crushing and the autogenous mill is selected to be used for the ultrafine crushing, and the mineral raw material granules with the particle size of-80~+90 mesh, -30~+50 mesh, -120~+150 mesh, -120~+150 mesh and -120~+150 mesh are obtained respectively.

[0091] The alkaline tundish covering agent formula is that the mineral raw material granules are proportioned according to the mass fraction ratio, then the DCS control system in the system issues a command to the mixer to set the wollastonite: obsidian: vein quartz: white marble: serpentine = 40:35:5:10:10, when the total production of this batch is 100 kg, the wollastonite setting value is calculated as 100 x (40 / 100) = 40 kg / h, the obsidian setting value is calculated as 100 x (35 / 100) = 35 kg / h, the vein quartz setting value is calculated as 100 x (5 / 100) = 5 kg / h, the white marble setting value is calculated as 100 x (10 / 100) = 10 kg / h and the serpentine setting value is calculated as 100 x (10 / 100) = 10 kg / h; the screw feeder in the system receives the command, first adds the corresponding weight of the mineral raw material granules and carries out low-speed stirring, the stirring speed is 25 rpm, after the feeding is completed, the low-speed stirring is ended and enters the high-speed stirring stage, the stirring speed is 45 rpm, the stirring time is 20 min. Finally, it enters the medium-low speed stirring stage, the stirring speed is 30 rpm, the stirring time is 10 min.

[0092] The mixed mineral granules obtained are transported by the belt conveyor to the electric heating rotary kiln in the system for drying, the drying section length is 10 m, the temperature rising rate is 20 ℃ / min, the drying temperature is 300 ℃, the drying time is 10 min; in order to control the water content of the covering agent to be less than 1% and the alkalinity to be >1, so as to obtain the MgO-Al2O3-SiO2-CaO quaternary component alkaline tundish covering agent product, the melting point of the tundish covering agent is 1380 ℃, the viscosity is 0.25 Pa.s, the prepared MgO-Al2O3-SiO2-CaO quaternary component alkaline tundish covering agent is sealed in bags by using the ton bag packaging machine.

[0093] The MgO-Al2O3-SiO2-CaO quaternary component basic tundish covering agent obtained above was subjected to molten steel liquid surface covering experiment. The prepared tundish covering agent was added to the molten steel surface (the steel type was 45 steel) at a usage amount of 2 kg per square meter. The tundish covering agent rapidly expanded and spread to completely cover the molten steel surface and maintained a good covering layer. The specific effect is shown in Figure 3 The tundish covering agent can cover the molten steel surface. The effective covering time is within 180 seconds. After working at a 1500℃ molten steel surface, the tundish covering agent was salvaged. The appearance effect is shown in Figure 7 The molten slag is complete and does not appear to be broken.

[0094] Example 3

[0095] This example uses the tundish covering agent preparation system in Example 3 to prepare a high magnesium component tundish covering agent.

[0096] First, serpentine was selected as the base material of the high magnesium component tundish covering agent, quicklime was selected as the alkalinity regulator, pitchstone was selected as the expandable mineral auxiliary material, and quartz sand was selected as the viscosity and melting point adjusting mineral. Then, the serpentine, quicklime, pitchstone, and quartz sand were subjected to controlled crushing, screening, and dust removal to obtain mineral raw material granules. The crushers in the system were selected to be jaw crushers, roller crushers, and cone crushers. The granules were screened using a graded inertial vibrating screen and a graded rolling screen at the stages of coarse crushing, medium crushing, fine crushing, and ultra-fine crushing. The dust in the workshop was collected using a bag dust collector. The coarse crushing was performed using a jaw crusher, the medium crushing was performed using a roller crusher, the fine crushing was performed using a cone crusher, and the ultra-fine crushing was performed using a self-mill. The mineral raw material granules with particle sizes of -60~+80 mesh, -100~+150 mesh, -30~+50 mesh, and -100~+150 mesh were obtained, respectively.

[0097] The high magnesium component tundish covering agent formula was prepared by mixing the mineral raw material granules in a mass fraction ratio. Then, the DCS control system in the system issued a command to set the serpentine, quicklime, pitchstone, and quartz sand to 50:15:15:20. When the total production of this batch was 100 kg, the set values of the serpentine, quicklime, pitchstone, and quartz sand were calculated to be 50 kg / h, 15 kg / h, 15 kg / h, and 15 kg / h, respectively. After receiving the command, the screw feeder in the system added the corresponding weight of mineral raw material granules and performed low-speed stirring at a speed of 30 rpm. After the feeding was completed, the low-speed stirring ended and entered the high-speed stirring stage at a speed of 75 rpm for 10 minutes. Finally, it entered the medium-low speed stirring stage at a speed of 50 rpm for 2 minutes.

[0098] The obtained mixed mineral particle mixture is transported by a belt conveyor to an electric heating rotary kiln in the system for drying, the drying section length is 10 m, the temperature rising rate is 20 ℃ / min, the drying temperature is 300 ℃, and the drying time is 10 min; in order to control the water content of the covering agent to be less than 1%, thereby obtaining the high-magnesium component tundish covering agent product, the melting point of the tundish covering agent is 1300 ℃, and the viscosity is 0.15 Pa.s, and the prepared high-magnesium component tundish covering agent is packaged and sealed by using a ton bag packaging machine.

[0099] The high-magnesium component tundish covering agent obtained above is subjected to molten steel liquid surface covering experiment, the prepared tundish covering agent is added to the steel liquid surface (the steel type is 45 steel) at a usage amount of 2 kg per square meter, the tundish covering agent rapidly expands and spreads to completely cover the steel liquid surface, and maintains a good covering layer, and the specific effect is as shown in Figure 4 The tundish covering agent can cover the steel liquid surface, and the effective covering time is within 50 s, and after working on the steel liquid surface at 1500 ℃, salvage is performed, and the appearance effect is as shown in Figure 8 The molten slag is complete and does not appear to be broken.

[0100] Example 4

[0101] This example uses the tundish covering agent preparation system in example 4 to prepare a high-temperature viscosity controllable tundish covering agent.

[0102] First, choose quicklime and perlite as the base material of the high-temperature viscosity controllable tundish covering agent, and natural quartz sand, quartzite and potassium feldspar as the viscosity adjusting mineral and melting point adjusting mineral, then control the crushing, screening and dust removal of the quicklime, perlite, natural quartz sand, quartzite and potassium feldspar to obtain mineral raw material particles, wherein the crusher in the system selects a jaw crusher, a roller crusher and a cone crusher, and a graded inertial vibrating screen and a graded rolling screen are used for screening in the stages of coarse crushing, medium crushing, fine crushing and ultra-fine crushing, and a bag dust collector is used to collect the dust in the workshop. The jaw crusher is selected for coarse crushing, the roller crusher is selected for medium crushing, the cone crusher is selected for fine crushing, and the autogenous mill is selected for ultra-fine crushing, to obtain mineral raw material particles with particle sizes of -80~+90 mesh, -20~+60 mesh, -100~+150 mesh, -100~+150 mesh and -60~+100 mesh, respectively.

[0103] The high-temperature viscosity controllable tundish covering agent formula is that the mineral raw material granules are proportioned according to mass fraction, and then the DCS control system in the system sends a command to the mixer to set the quicklime: perlite: natural quartz sand: quartzite: potassium feldspar = 50:31:5:5:9, when the total production of the batch is 100 kg, the quicklime setting value is calculated as 100 x (50 / 100) = 50 kg / h, the perlite setting value is 100 x (31 / 100) = 31 kg / h, the natural quartz sand setting value is 100 x (5 / 100) = 5 kg / h, the quartzite setting value is 100 x (5 / 100) = 5 kg / h, and the potassium feldspar setting value is 100 x (9 / 100) = 9 kg / h; the screw feeder in the system receives the command, first adds the corresponding weight of the mineral raw material granules and stirs at a low speed, the stirring speed is 25 rpm, after the feeding is completed, the low-speed stirring is ended and enters the high-speed stirring stage, the stirring speed is 45 rpm, and the stirring time is 20 min. Finally, it enters the medium-low speed stirring stage, the stirring speed is 30 rpm, and the stirring time is 10 min.

[0104] The obtained mixed mineral granules are transported by a belt conveyor to the electric heating rotary kiln in the system for drying, the drying section length is 10 m, the temperature rising rate is 20 ℃ / min, the drying temperature is 300 ℃, and the drying time is 10 min; in order to control the water content of the covering agent to be less than 1%, thereby obtaining the high-temperature viscosity controllable tundish covering agent product, the melting point of the tundish covering agent is 1300 ℃, and the viscosity is 0.1 Pa.s. The prepared high-temperature viscosity controllable tundish covering agent is packaged and sealed by a ton bag packaging machine.

[0105] The high-temperature viscosity controllable tundish covering agent obtained above is subjected to molten steel liquid level covering experiment, the prepared intermediate covering agent is added to the steel liquid surface (the steel type is 45 steel) at a usage of 1 kg per square meter, the covering agent expands and spreads rapidly to completely cover the steel liquid surface, and maintains a good covering layer, the specific effect is as shown in Figure 5 The tundish covering agent can cover the steel liquid surface, the effective covering time is within 40 s, and after working at the steel liquid surface of 1500 ℃, it is salvaged, the appearance effect is as shown in Figure 9 The molten slag is complete and does not appear to be broken.

[0106] Although the present application has been described above with reference to the example embodiments and the accompanying drawings, it should be clear for those skilled in the art that various modifications can be made to the above embodiments without departing from the spirit and scope of the claims.

Claims

1. An intermediate tundish cover preparation system characterized by, The system comprises a mineral raw material pretreatment unit, a mineral particle matching unit, a mineral particle mixture drying unit and a product packaging and storage unit, and conveyors are arranged between the units for conveying, The mineral raw material pretreatment unit comprises a mineral raw material storage bin, a crushing mechanism, a screening mechanism and a mineral particle material storage bin, and can process the mineral raw material into mineral particle materials of different particle sizes and deliver them to the mineral particle matching unit; The mineral particle matching unit comprises a feeder, a mixer and a mineral particle mixture storage bin, and can match and uniformly mix the mineral particle materials obtained from the mineral raw material pretreatment unit to obtain mineral particle mixtures; The mineral particle mixture drying unit comprises a drying kiln, and can dry the mineral particle mixtures obtained from the mineral particle matching unit to obtain intermediate coating agents; The product packaging and storage unit comprises a weighing and packaging mechanism and a product storage bin, and can weigh and package the products; a conveyor is arranged between the weighing and packaging mechanism and the product storage bin.

2. The intermediate cover preparation system of claim 1, wherein, The mineral raw material storage bin comprises a base material mineral storage bin, an expansive mineral auxiliary material storage bin, a viscosity adjusting mineral storage bin and a melting point adjusting mineral storage bin; the base material mineral storage bin, the expansive mineral auxiliary material storage bin, the viscosity adjusting mineral storage bin and the melting point adjusting mineral storage bin each comprise a plurality of secondary storage bins for storing different types of mineral raw materials.

3. The intermediate cover preparation system of claim 1, wherein, The crushing mechanism comprises a coarse crushing section, a medium crushing section, a fine crushing section and an ultra-fine crushing section connected by a belt conveyor; the coarse crushing section comprises at least one of a jaw crusher and a roller crusher; the medium crushing section comprises at least one of a roller crusher and a cone crusher; the fine crushing section comprises at least one of an impact crusher or a cone crusher; and the ultra-fine crushing section comprises at least one of a roller crusher, a high-pressure roller mill, a ball mill and a autogenous mill. The screening mechanism comprises at least one of a classification inertial vibrating screen and a classification rolling screen. The conveyor comprises at least one of a fixed belt conveyor, a telescopic belt conveyor and a turning belt conveyor. The mineral particle material storage bin is used for storing different types of mineral particle materials, and comprises a plurality of secondary storage bins for storing mineral particle materials of different categories and particle sizes; the bottom of each secondary storage bin is provided with a screw feeder or a gate for controlling the discharging speed.

4. The intermediate cover preparation system of claim 1, wherein, The mixer and the mineral particle mixture storage bin are connected by a belt conveyor; the mixer comprises at least one of a screw belt mixer, a paddle mixer, a planetary power mixer and a V-shaped mixer. The mineral particle mixture storage bin is used for storing mineral particle mixtures of different types or proportions of intermediate coating agents; and the mineral particle mixture storage bin is a temporary storage bin with a screw feeder.

5. The intermediate cover preparation system of claim 1, wherein, The matching is automatically weighed and matched by a PLC / DCS control system, and different categories and particle sizes of mineral particle materials can be weighed and quantitatively conveyed; The PLC / DCS system is connected with the feeder and the mixer for controlling the feeding amount, mixing time, stirring speed and feeding / discharging sequence, and realizing automatic operation.

6. The intermediate cover preparation system of claim 1, wherein, The drying kiln comprises at least one of an electric heating rotary kiln, a fuel-fired rotary kiln and an oil-fired rotary kiln. The temperature range of the inlet to the outlet of the kiln body of the electric heating rotary kiln is 100-300 DEG C, the length of the kiln body is 10-30 m, the temperature gradient is 10-30 DEG C / m, and the drying time of the material is 10-30 min. The temperature range of the inlet to the outlet of the kiln body of the fuel gas rotary kiln and the fuel oil rotary kiln is 150-300 DEG C, the length of the kiln body is 10-20 m, the temperature gradient is 6-15 DEG C / m, and the pre-drying time of the material is 3-30 min. The moisture of the intermediate covering agent is less than or equal to 1%, and the moisture is adsorbed water.

7. The intermediate cover preparation system of claim 1, wherein, The weighing and packaging mechanism can automatically control the metering, loading and packaging of the product, and the weighing and packaging mechanism comprises at least one of an open packaging machine and a ton bag packaging machine. The product storage bin comprises a basic intermediate covering agent storage bin, an acidic intermediate covering agent storage bin, a high-magnesium component intermediate covering agent storage bin and a high-temperature viscosity controllable intermediate covering agent storage bin.

8. The intermediate cover preparation system of claim 1, wherein, The intermediate covering agent preparation system further comprises a dust removal unit, and the dust suction ports of the dust removal unit are respectively arranged at the crushing mechanism, the screening mechanism and the product packaging and storage unit; the dust suction ports are connected with the bag dust collector through pipelines.

9. The intermediate cover preparation system of claim 1, wherein, The mineral raw materials comprise calcium-based mineral raw materials, siliceous mineral raw materials, magnesium-rich mineral raw materials, expandable mineral raw materials, viscosity adjusting mineral raw materials and melting point adjusting mineral raw materials. The calcium-based mineral raw materials comprise at least one of quicklime, wollastonite and calcined dolomite; the siliceous mineral raw materials comprise at least one of quartz minerals, diatomite or zeolite with high silicon content, and the quartz minerals comprise at least one of vein quartz, natural quartz sand, white granite and quartzite; the magnesium-rich mineral raw materials comprise at least one of serpentine, peridotite, periclase, brucite, talc and calcined dolomite; the expandable mineral raw materials comprise at least one of perlite, obsidian, pitchstone, pumice-like perlite and vermiculite; and the viscosity adjusting mineral raw materials and the melting point adjusting mineral raw materials comprise serpentine, periclase, quartz minerals, potassium feldspar, sodium feldspar and feldspar derivatives, and the derivatives comprise at least one of orthoclase, microcline, bytownite and labradorite.

10. Use of an intermediate tundish cover preparation system, characterized in that The intermediate covering agent preparation system is the system of any one of claims 1-9, and the application comprises using the intermediate covering agent preparation system to prepare high-magnesium component intermediate covering agents, basic intermediate covering agents, acidic intermediate covering agents and high-temperature viscosity controllable intermediate covering agents.

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