ABOUT US
HAOYANG
The diversified development of refractory raw materials adapts to the new normal state of steel industry
Source:
|
Author:haoyangnaihuo
|
Published time: 2018-03-27
|
969 Views
|
Share:
Refractory materials are the basic materials of the steel industry. The refractory industry and the iron and steel industry promote each other and develop together. As China's economy has entered a new normal, the iron and steel industry has emerged a series of new features: excess production capacity, declining profitability, enhanced environmental resource constraints, and transformation and upgrading are facing more challenges. The new normal of the iron and steel industry puts forward new requirements, new thinking, and promotes new changes in the refractory industry that is in the upper reaches of the industrial chain. The performance and application of refractories have been characterized by characteristics, diversification, refinement, high efficiency, and low consumption in recent years. The development of refractory materials must be commensurate with it, and will also be diversified, enriched, and featured. Situation evolution.
Refractory materials are the basic materials of the steel industry. The refractory industry and the iron and steel industry promote each other and develop together. As China's economy has entered a new normal, the iron and steel industry has emerged a series of new features: excess production capacity, declining profitability, enhanced environmental resource constraints, and transformation and upgrading are facing more challenges. The new normal of the iron and steel industry puts forward new requirements, new thinking, and promotes new changes in the refractory industry that is in the upper reaches of the industrial chain. The performance and application of refractories have been characterized by characteristics, diversification, refinement, high efficiency, and low consumption in recent years. The development of refractory materials must be commensurate with it, and will also be diversified, enriched, and featured. Situation evolution.
1 Multiple reflections on new requirements for refractory materials
1.1 New Requirements for Green Environmental Protection
1.1.1 Meeting the requirements of clean steel smelting
Clean steel smelting puts forward new requirements for the reduction and avoidance of pollution of molten iron and molten steel for iron-making, steel-making auxiliary materials, and refractories. Research and practice have found that aluminum-silicon refractories are contaminated with molten steel, magnesium materials are not contaminated, and materials containing free CaO are not only non-polluting, but also have the effect of clean steel. For this reason, magnesium oxide and calcium raw materials containing free CaO, which have good resistance to hydration and are fused, are favored.
In order to reduce the carbon pollution of the molten steel with carbon-containing refractories, the carbon content of the carbon composite refractory material needs to be reduced. In order to eliminate the side effects of carbon reduction against thermal shock and erosion resistance, diffuse carbon sources need to be introduced. It promotes the development and production of various nano-carbon sources suitable for refractory materials such as carbon black, carbon nanotubes, and graphene.
In order to reduce the "rephosphorization" effect of the tundish working lining on the molten steel after refining, a low phosphorous or non-phosphorus binding system was developed.
1.1.2 Meeting the "Green" Requirements of the Iron and Steel Industry
In view of the carcinogenic effect of Cr6+, chromium-containing refractories have been listed by the State as a restricted use product, and it is imperative to replace chromium-containing materials with new materials with low chromium and chromium. Such as high-performance magnesia carbon bricks, magnesium alumina spinel bricks, magnesium zirconium bricks and other refining furnaces used in RH, can replace the traditional magnesium chrome bricks.
The slag used in blast furnace taps generally uses tar as a binding agent. To reduce the environmental pollution during production and use, people are encouraged to develop new environmentally friendly binders.
In order to reduce the environmental and human hazards of the production, processing, installation, and post-treatment of traditional aluminosilicate refractory fibers, biodegradable calcium magnesium magnesium silicon refractory fibers have been developed and used.
1.1.3 Meeting the Requirements for Energy Saving and Emission Reduction in the Iron and Steel Industry
As an industrial lining material, the use of energy-saving refractory materials is imperative. New materials that have been developed and applied in recent years, which are beneficial to energy conservation, include: microporous structural light mullite-quality raw materials, mullite hollow spheres, lightweight microporous sintered alumina, and CA6-MA multiphase lightweight bone Materials, olivine light material, spinel light material, nanoporous silica powder and its polymers.
1.2 Development of economical refractory materials
At present, the refractory materials industry related to the refractory raw material industry chain and the iron and steel industry are in a downturn, and low-cost winning bids become the direction of the supply chain relationship. On the other hand, some high-grade natural mineral raw materials, such as high-alumina bauxite, gradually depleted, the ore grade decreased and the quality fluctuates. The technical deployment route of improving the performance of high-grade raw materials and reducing the cost of cheap raw materials gradually came to an end. Guided by this orientation, cheap, economical refractory raw materials and products will become a major trend.
Low consumption is the main direction of development for economical refractory materials. The main direction for raw materials to achieve low consumption is to expand the use of natural raw materials, light burning materials, and recycled materials. In order to ensure the high temperature volume stability of refractory materials, natural raw materials must be sintered or electrofused at high temperatures to make them rhythmic and as thermodynamic equilibrium as possible. This will lead to high energy consumption and will also result in a certain degree of capacity surplus. In a sense, it will cause invisible resources and energy waste. It can develop and apply non-equilibrium raw materials that have a lower temperature than conventional sintering, and even can directly add a certain amount of natural raw materials to reduce the energy consumption of refractory materials to some extent.
Studies have shown that the addition of a certain amount of natural raw materials castable has a good effect, the raw material decomposition of gases evolved after the formation of channels, help to improve the burst resistance. The addition of raw coal gangue or light coal gangue in aluminum-silicon castables produces mullite in-situ after heating, which can increase its thermal bending strength, load softening temperature, and improve thermal shock resistance. Lightweight material.
Faced with the depletion of high-grade ore, low-grade ore is increasingly becoming the main source of raw materials. People must rethink the scientificity, rationality and adaptability of raw materials and product indicators, and optimize the allocation of raw materials to make them more excellent. Competitive price/performance ratio. Consideration should be given to appropriately reducing the A12O3 content and bulk density of certain high-aluminum refractory materials used in non-melt erosion and erosion sites, and to relax the requirements for the impurity content of the aluminum-silicone refractory materials used in certain intermediate-low temperature locations.
1.3 Diversification
1.3.1 Diversification of raw materials, forms and characteristics
In recent years, there have been new developments in new varieties and diversification of alkaline raw materials. For example, through the addition of other components in MgO, the new materials developed are magnesium-magnesium spinel, magnesium-aluminum-iron composite spinel, magnesium-aluminum-titanium composite spinel, etc.; the synthesis of forsterite heavy and light raw materials is underway; Rare-earth-modified MgO-CaO sand and fused MgO-CaO sand have been put on the market; periclase-spinel two-phase composite sintering materials and electric frits have been put on the market. The new CaO-containing raw materials developed include calcium hexaaluminate, anorthite, calcium titanoaluminate, and CA6-MA composite raw materials.
To meet the needs of different conditions of use, the use of temperature, bauxite clinker series still need to be improved. At present, the division of Al2O3 content is still extensive; the higher the bulk density, the better, the lack of serialization; the particle size supply is traditional and lacks diversity. Considering the bulk density, there is no shortage of heavy and light raw materials, but the medium density material is almost in blank. At present, heavy refractories are used. Some may use relatively lightweight materials, or may reduce the bulk density of currently used heavy materials by 0.1 to 0.5 g?cm-3 or more.
In order to compensate for the lack of one or more properties of a single refractory raw material and balance its overall performance, multiphase composite raw materials are gradually accepted and focused. For example, raw materials of zirconium mullite developed on the basis of corundum and mullite raw materials have both corrosion resistance and low expansivity, and the properties of the modified zirconium corundum mullite are superior. The MgO-CaO-Fe2O3-based synthetic material, the magnesium-aluminum-iron spinel synthetic material, the MgO-ZrO2-TiO2-based synthetic material, the ZrB2-SiC material, and the newly emerged A12O3-TiO2-CaO synthetic material are used for multi-phase composites at the bottom of the furnace. The raw materials all have relatively better overall properties. Inspired by gradient functional materials, the concept of gradient materials has been proposed and explored in recent years. Such as: the use of surface carbonation production of waterproof magnesium calcium sand; In order to take into account the particles of high strength and low thermal conductivity, can make its bulk density gradient from surface to interior; particle surface components and internal components of the difference The design can help to achieve the positive effect of in-situ interface formation.
In recent years, "combination of raw materials" has gradually emerged. It broke through the concept of traditional single raw materials. For example, the cement supplier mixes the water reducer, retarder, coagulant, plasticizer and cement with the cement according to the season, user's product series, characteristics, construction and other requirements, and provides it to the customer to improve the convenience of use. Operational. Some suppliers directly provide high-grade aluminum-magnesium castable materials for ladle, optimize various micro-powders and water-reducing agents, and combine packages for sale.
It has been found that many so-called "in situ refractories" tend to perform better. Such as in-situ generation of mullite, spinel, silicon carbide, silicon nitride, sialon, etc., the reinforcement and modification of the product is often greater than the corresponding pre-synthesized material. The raw material containing the target component is pre-configured in the material so as to generate the desired target component and phase during the production and service process, and is a scheme for improving the price and quantity of the product.
1.3.2 Diversification of raw material status
In addition to the traditional oxide, elemental and non-oxide materials, the refractory materials have been expanded from the traditional non-metal to metal materials, and the raw material state has expanded from solid to liquid and gas. For example, metals or alloys (mostly A1 and Si) are commonly used as important raw materials in the sliding nozzle and ceramic cup products. They react with the surrounding N2(g) and CO(g) during production and use. Generates non-oxide to enhance the high temperature performance of the material. In this case, both metal and gaseous raw materials are involved. Another example is the addition of steel fibers in castables to increase their resistance to cracking and spalling.
1.3.3 The favorable shape of raw materials
In addition to the "new" raw materials formed by changes in the composition and characteristics of raw materials, there are also "new" raw materials formed by changes in the shape of raw materials. If the fine powder size is from ordinary fineness (tens to hundreds of micrometers) to micrometers or even sub-micron, nanometer scale, the technological added value of raw materials can be greatly improved; the spherical and near-spherical aggregates can help to improve the quality of amorphous refractories. Rheological properties; hollow aggregates are conducive to thermal insulation; rough and uneven surface aggregates are conducive to improved grip strength; short cylindrical or tubular aggregates are beneficial to improve thermal shock resistance; fibrous or flexible materials are beneficial to improve strength and resistance. Thermal shock. The direct production of spherical lightweight aggregates with different particle sizes by granulation can avoid the waste caused by the production of a certain proportion of excessively small particles and fine powder when the lightweight blocks are broken; the particles with small obtuse angle and long diameter ratio are favorable to Mud compression molding and so on.
Another manifestation of advantageous raw material forms is pre-combined or service-type raw materials. Raw material suppliers supply a customer with a certain proportion of granular materials according to customer requirements. The user directly mixes the particles with the fine powder to reduce the raw material processing, screening, and mixing operations.
1.3.4 enrichment of raw material standards
Refine the grades and standards of raw materials. The same grade of bauxite clinker can also be serialized according to the bulk density, and the appropriate bulk density of the homogeneous material should be selected according to the use conditions. However, there are no standards such as alumina homogeneous material, pyrophyllite, forsterite, recycled raw materials, and non-graphite carbonaceous raw materials for refractory materials. With the improvement of the level of mine development and management, coupled with the complexity, variability and uniqueness of mineral reserves, it is necessary to refine the relevant raw material varieties, and to supplement and improve the systematization, adaptability and individualization of the grades of raw material standards.
1.4 The requirements of sustainable development
Refractory materials can be divided into three categories: acidic, alkaline and neutral. At present, the proportion of neutral aluminum-silicon refractories production has been consistently high. The rapid development of the aluminum industry and refractories industry has resulted in a huge consumption of refractory clay and bauxite, and the sharp drop in resource reserves has caused the price of alumina clinker to soar. This will inevitably affect the production and application of aluminum-silicon refractory materials. In the future, more attention should be paid to acidic, semi-acidic and alkaline, semi-alkali refractories, and production, and the advantages of R&D, technology, capital, and policies should be gathered on the use of relatively abundant and inexpensive resources such as silica and magnesite. Deep processing, increase its technological added value, develop more varieties, improve its adaptability. Properly balance the ratio of acid, alkaline and neutral refractory materials, and balance the consumption rate of silica, magnesite and bauxite. In the design of the kiln material care more acidic, alkaline refractories, so that it has a greater use. Improve the adaptability of raw material supply to the development of refractory materials and the sustainability of the industry's future development.
2 Conclusion
At present, China's iron and steel industry and refractories industry are undergoing a transition from the period of incremental expansion of production to the period of improvement of quality and efficiency. New requirements have been put forward for refractory materials, and the adaptability of fire-resistant raw materials has to be improved to center on the steel industry and refractory materials. The industry's new needs, adhere to the sustainable development direction, develop a variety of high-quality raw materials. In addition to the innovation of traditional raw materials, the directions worth paying attention and efforts in the future are: 1) Serialization, diversification and integration of raw materials; 2) New raw materials with unique properties; 3) Green materials in a broad sense. Therefore, we should strengthen the foresight, guidance, and supporting role of science and technology in the development of raw materials, actively develop new low-cost, high-efficiency, green, high-quality raw materials to meet the new needs of the refractory industry and promote the healthy development of the steel industry.
1 Multiple reflections on new requirements for refractory materials
1.1 New Requirements for Green Environmental Protection
1.1.1 Meeting the requirements of clean steel smelting
Clean steel smelting puts forward new requirements for the reduction and avoidance of pollution of molten iron and molten steel for iron-making, steel-making auxiliary materials, and refractories. Research and practice have found that aluminum-silicon refractories are contaminated with molten steel, magnesium materials are not contaminated, and materials containing free CaO are not only non-polluting, but also have the effect of clean steel. For this reason, magnesium oxide and calcium raw materials containing free CaO, which have good resistance to hydration and are fused, are favored.
In order to reduce the carbon pollution of the molten steel with carbon-containing refractories, the carbon content of the carbon composite refractory material needs to be reduced. In order to eliminate the side effects of carbon reduction against thermal shock and erosion resistance, diffuse carbon sources need to be introduced. It promotes the development and production of various nano-carbon sources suitable for refractory materials such as carbon black, carbon nanotubes, and graphene.
In order to reduce the "rephosphorization" effect of the tundish working lining on the molten steel after refining, a low phosphorous or non-phosphorus binding system was developed.
1.1.2 Meeting the "Green" Requirements of the Iron and Steel Industry
In view of the carcinogenic effect of Cr6+, chromium-containing refractories have been listed by the State as a restricted use product, and it is imperative to replace chromium-containing materials with new materials with low chromium and chromium. Such as high-performance magnesia carbon bricks, magnesium alumina spinel bricks, magnesium zirconium bricks and other refining furnaces used in RH, can replace the traditional magnesium chrome bricks.
The slag used in blast furnace taps generally uses tar as a binding agent. To reduce the environmental pollution during production and use, people are encouraged to develop new environmentally friendly binders.
In order to reduce the environmental and human hazards of the production, processing, installation, and post-treatment of traditional aluminosilicate refractory fibers, biodegradable calcium magnesium magnesium silicon refractory fibers have been developed and used.
1.1.3 Meeting the Requirements for Energy Saving and Emission Reduction in the Iron and Steel Industry
As an industrial lining material, the use of energy-saving refractory materials is imperative. New materials that have been developed and applied in recent years, which are beneficial to energy conservation, include: microporous structural light mullite-quality raw materials, mullite hollow spheres, lightweight microporous sintered alumina, and CA6-MA multiphase lightweight bone Materials, olivine light material, spinel light material, nanoporous silica powder and its polymers.
1.2 Development of economical refractory materials
At present, the refractory materials industry related to the refractory raw material industry chain and the iron and steel industry are in a downturn, and low-cost winning bids become the direction of the supply chain relationship. On the other hand, some high-grade natural mineral raw materials, such as high-alumina bauxite, gradually depleted, the ore grade decreased and the quality fluctuates. The technical deployment route of improving the performance of high-grade raw materials and reducing the cost of cheap raw materials gradually came to an end. Guided by this orientation, cheap, economical refractory raw materials and products will become a major trend.
Low consumption is the main direction of development for economical refractory materials. The main direction for raw materials to achieve low consumption is to expand the use of natural raw materials, light burning materials, and recycled materials. In order to ensure the high temperature volume stability of refractory materials, natural raw materials must be sintered or electrofused at high temperatures to make them rhythmic and as thermodynamic equilibrium as possible. This will lead to high energy consumption and will also result in a certain degree of capacity surplus. In a sense, it will cause invisible resources and energy waste. It can develop and apply non-equilibrium raw materials that have a lower temperature than conventional sintering, and even can directly add a certain amount of natural raw materials to reduce the energy consumption of refractory materials to some extent.
Studies have shown that the addition of a certain amount of natural raw materials castable has a good effect, the raw material decomposition of gases evolved after the formation of channels, help to improve the burst resistance. The addition of raw coal gangue or light coal gangue in aluminum-silicon castables produces mullite in-situ after heating, which can increase its thermal bending strength, load softening temperature, and improve thermal shock resistance. Lightweight material.
Faced with the depletion of high-grade ore, low-grade ore is increasingly becoming the main source of raw materials. People must rethink the scientificity, rationality and adaptability of raw materials and product indicators, and optimize the allocation of raw materials to make them more excellent. Competitive price/performance ratio. Consideration should be given to appropriately reducing the A12O3 content and bulk density of certain high-aluminum refractory materials used in non-melt erosion and erosion sites, and to relax the requirements for the impurity content of the aluminum-silicone refractory materials used in certain intermediate-low temperature locations.
1.3 Diversification
1.3.1 Diversification of raw materials, forms and characteristics
In recent years, there have been new developments in new varieties and diversification of alkaline raw materials. For example, through the addition of other components in MgO, the new materials developed are magnesium-magnesium spinel, magnesium-aluminum-iron composite spinel, magnesium-aluminum-titanium composite spinel, etc.; the synthesis of forsterite heavy and light raw materials is underway; Rare-earth-modified MgO-CaO sand and fused MgO-CaO sand have been put on the market; periclase-spinel two-phase composite sintering materials and electric frits have been put on the market. The new CaO-containing raw materials developed include calcium hexaaluminate, anorthite, calcium titanoaluminate, and CA6-MA composite raw materials.
To meet the needs of different conditions of use, the use of temperature, bauxite clinker series still need to be improved. At present, the division of Al2O3 content is still extensive; the higher the bulk density, the better, the lack of serialization; the particle size supply is traditional and lacks diversity. Considering the bulk density, there is no shortage of heavy and light raw materials, but the medium density material is almost in blank. At present, heavy refractories are used. Some may use relatively lightweight materials, or may reduce the bulk density of currently used heavy materials by 0.1 to 0.5 g?cm-3 or more.
In order to compensate for the lack of one or more properties of a single refractory raw material and balance its overall performance, multiphase composite raw materials are gradually accepted and focused. For example, raw materials of zirconium mullite developed on the basis of corundum and mullite raw materials have both corrosion resistance and low expansivity, and the properties of the modified zirconium corundum mullite are superior. The MgO-CaO-Fe2O3-based synthetic material, the magnesium-aluminum-iron spinel synthetic material, the MgO-ZrO2-TiO2-based synthetic material, the ZrB2-SiC material, and the newly emerged A12O3-TiO2-CaO synthetic material are used for multi-phase composites at the bottom of the furnace. The raw materials all have relatively better overall properties. Inspired by gradient functional materials, the concept of gradient materials has been proposed and explored in recent years. Such as: the use of surface carbonation production of waterproof magnesium calcium sand; In order to take into account the particles of high strength and low thermal conductivity, can make its bulk density gradient from surface to interior; particle surface components and internal components of the difference The design can help to achieve the positive effect of in-situ interface formation.
In recent years, "combination of raw materials" has gradually emerged. It broke through the concept of traditional single raw materials. For example, the cement supplier mixes the water reducer, retarder, coagulant, plasticizer and cement with the cement according to the season, user's product series, characteristics, construction and other requirements, and provides it to the customer to improve the convenience of use. Operational. Some suppliers directly provide high-grade aluminum-magnesium castable materials for ladle, optimize various micro-powders and water-reducing agents, and combine packages for sale.
It has been found that many so-called "in situ refractories" tend to perform better. Such as in-situ generation of mullite, spinel, silicon carbide, silicon nitride, sialon, etc., the reinforcement and modification of the product is often greater than the corresponding pre-synthesized material. The raw material containing the target component is pre-configured in the material so as to generate the desired target component and phase during the production and service process, and is a scheme for improving the price and quantity of the product.
1.3.2 Diversification of raw material status
In addition to the traditional oxide, elemental and non-oxide materials, the refractory materials have been expanded from the traditional non-metal to metal materials, and the raw material state has expanded from solid to liquid and gas. For example, metals or alloys (mostly A1 and Si) are commonly used as important raw materials in the sliding nozzle and ceramic cup products. They react with the surrounding N2(g) and CO(g) during production and use. Generates non-oxide to enhance the high temperature performance of the material. In this case, both metal and gaseous raw materials are involved. Another example is the addition of steel fibers in castables to increase their resistance to cracking and spalling.
1.3.3 The favorable shape of raw materials
In addition to the "new" raw materials formed by changes in the composition and characteristics of raw materials, there are also "new" raw materials formed by changes in the shape of raw materials. If the fine powder size is from ordinary fineness (tens to hundreds of micrometers) to micrometers or even sub-micron, nanometer scale, the technological added value of raw materials can be greatly improved; the spherical and near-spherical aggregates can help to improve the quality of amorphous refractories. Rheological properties; hollow aggregates are conducive to thermal insulation; rough and uneven surface aggregates are conducive to improved grip strength; short cylindrical or tubular aggregates are beneficial to improve thermal shock resistance; fibrous or flexible materials are beneficial to improve strength and resistance. Thermal shock. The direct production of spherical lightweight aggregates with different particle sizes by granulation can avoid the waste caused by the production of a certain proportion of excessively small particles and fine powder when the lightweight blocks are broken; the particles with small obtuse angle and long diameter ratio are favorable to Mud compression molding and so on.
Another manifestation of advantageous raw material forms is pre-combined or service-type raw materials. Raw material suppliers supply a customer with a certain proportion of granular materials according to customer requirements. The user directly mixes the particles with the fine powder to reduce the raw material processing, screening, and mixing operations.
1.3.4 enrichment of raw material standards
Refine the grades and standards of raw materials. The same grade of bauxite clinker can also be serialized according to the bulk density, and the appropriate bulk density of the homogeneous material should be selected according to the use conditions. However, there are no standards such as alumina homogeneous material, pyrophyllite, forsterite, recycled raw materials, and non-graphite carbonaceous raw materials for refractory materials. With the improvement of the level of mine development and management, coupled with the complexity, variability and uniqueness of mineral reserves, it is necessary to refine the relevant raw material varieties, and to supplement and improve the systematization, adaptability and individualization of the grades of raw material standards.
1.4 The requirements of sustainable development
Refractory materials can be divided into three categories: acidic, alkaline and neutral. At present, the proportion of neutral aluminum-silicon refractories production has been consistently high. The rapid development of the aluminum industry and refractories industry has resulted in a huge consumption of refractory clay and bauxite, and the sharp drop in resource reserves has caused the price of alumina clinker to soar. This will inevitably affect the production and application of aluminum-silicon refractory materials. In the future, more attention should be paid to acidic, semi-acidic and alkaline, semi-alkali refractories, and production, and the advantages of R&D, technology, capital, and policies should be gathered on the use of relatively abundant and inexpensive resources such as silica and magnesite. Deep processing, increase its technological added value, develop more varieties, improve its adaptability. Properly balance the ratio of acid, alkaline and neutral refractory materials, and balance the consumption rate of silica, magnesite and bauxite. In the design of the kiln material care more acidic, alkaline refractories, so that it has a greater use. Improve the adaptability of raw material supply to the development of refractory materials and the sustainability of the industry's future development.
2 Conclusion
At present, China's iron and steel industry and refractories industry are undergoing a transition from the period of incremental expansion of production to the period of improvement of quality and efficiency. New requirements have been put forward for refractory materials, and the adaptability of fire-resistant raw materials has to be improved to center on the steel industry and refractory materials. The industry's new needs, adhere to the sustainable development direction, develop a variety of high-quality raw materials. In addition to the innovation of traditional raw materials, the directions worth paying attention and efforts in the future are: 1) Serialization, diversification and integration of raw materials; 2) New raw materials with unique properties; 3) Green materials in a broad sense. Therefore, we should strengthen the foresight, guidance, and supporting role of science and technology in the development of raw materials, actively develop new low-cost, high-efficiency, green, high-quality raw materials to meet the new needs of the refractory industry and promote the healthy development of the steel industry.
Next：
None
Add：Gangyaolin village, Ximu Town, Haicheng City, Liaoning Province
Tel：0412-3744222 E-mail：haoyangref@163.com
Sales phone：18804257566/18804257966
haicheng haoyang refactory co.,ltd.
All right：Haicheng haoyang refactory co.,ltd. By：29net.cn
Light burning magnesium ball|Magnesite|Light burned magnesium oxide|Heavy burned magnesia|Mid-range magnesia|High purity magnesia|Fused magnesia|Converter lining magnesia carbon brick|Converter large repair material|Converter spray material|Furnace supplement brick|Converter slag balls|Converter final slag modifier|Electric furnace lining magnesia carbon brick|Electric furnace bottom ramming material|Electric furnace spraying material|Electric furnace tap brick|Steel lining brick|Ladle pouring material|Tundish dry vibrating material|Tundish permanent layer castable material|Tundish slag, impact plate|Tundish covering agent|Magnesia brick|Magnesium-alumina spinel brick|Magnesium chrome brick|Magnesium calcium brick|Fluorite block ore|Fluorite balls
