Introduction
The main crystal phase of Medium-Grade Magnesia is periclase. The crystals are mostly rounded and irregular granular bodies with large sizes, accompanied by silicate phases. The bonding is dominated by the cementation of silicate phases, and there are also many pores. The composition ranges between C₃S-C₂S-C₃MS₂-M₂S, and the performance is good.
Medium-Grade Magnesia is produced by processing high-quality magnesite ore through light burning, fine grinding, balling, calcination, and other methods, thereby enhancing its density and purity. Its MgO content is ≥ 95%, with a bulk density of ≥ 3.15 g/cm³ (generally 3.20–3.25 g/cm³). It is classified into two grades: 94 and 95. Currently, mid-range magnesia is an important category of magnesia products, widely used as a raw material in fired bricks (such as mid-range magnesia bricks) and some unshaped magnesia refractories.
Advantages and Market Positioning
Performance Advantages: Compared with ordinary magnesia, mid-range magnesia features denser crystallization and stronger slag resistance, meeting the requirements for medium-to-high temperature (1600–1800°C) service. Compared with high-purity magnesia, it reduces costs by 15%–30%, offering outstanding cost-effectiveness.
Market Positioning: It is primarily applied in scenarios with high refractory performance requirements that are not extremely harsh, such as long-life converters and large steel complex kiln construction. It serves as one of the mainstream raw materials in the refractory industry.
Physical And Chemical Specifications
|
Indicator |
MgO%≥ |
SiO2%≤ |
CaO%≤ |
B.D.g/cm3≥ |
Loss on Ignition (LOI)%≤ |
|
Grade |
|||||
|
YXMS95A(Oil firing) |
95 | 1.4 | 1.6 | 3.26 | 0.3 |
|
YXMS95B(Oil firing) |
94.5 | 1.6 | 1.8 | 3.25 | 0.3 |
|
YXMS95A(Scorch) |
95 | 2.0 | 1.6 | 3.20 | 0.3 |
|
YXMS95B(Scorch) |
94.5 | 2.5 | 1.8 | 3.20 | 0.3 |
Process
Raw Material Selection:
The main raw material is special-grade or first-grade magnesite (with MgO content ≥47% and CaO/SiO₂ ≤1.5). Some processes use lightly burnt magnesium oxide (with 95% or 97% MgO) as the raw material.
Impurity Control:
The contents of Fe₂O₃, Al₂O₃, SiO₂, and other impurities are strictly limited to avoid affecting the performance of refractories.
Production Process:
Traditional Process: Magnesite → light burning (800–1000°C) → fine grinding (particle size ≤0.088mm accounts for over 80%) → ball pressing (pellet density ≥2.5g/cm³) → high-temperature sintering (vertical kiln/tunnel kiln, 1600–1800°C) → cooling and crushing.
New Process: Lightly burnt magnesium powder is used as the raw material. After balling, it is calcined in a high-temperature vertical kiln. The crystal structure is optimized by controlling the heating rate and holding time.
Application
Medium-grade magnesia is mainly used to produce high-grade alkaline shaped or unshaped refractories, with its finished products primarily applied in industries such as metallurgy, building materials, non-ferrous metals, and chemicals.
In metallurgy, medium-grade magnesia is used to manufacture metallurgical powder for joining furnace bottoms and walls, produce slurry for spray-paved furnace linings, and make magnesia bricks and magnesia-chrome bricks. Besides being used as furnace bottom linings, it is also widely utilized in electric steelmaking furnaces, heating furnaces, non-ferrous metal converting furnaces, and rotary kilns.
Iron and Steel Industry
•Ramming materials for the bottoms and linings of steelmaking open-hearth furnaces and electric furnaces;
•Magnesia refractory bricks for converter slag splashing protection;
•Heating furnace linings, taphole bricks, etc.
Non-Ferrous Metal Smelting
•Linings for converting furnaces used in non-ferrous metals such as copper, nickel, and lead;
•Refractory layers for the high-temperature zones of rotary kilns.
Other Fields
•Lattice bricks for glass kiln regenerators;
•Refractories for the burning zones of cement kilns;
•Thermal insulation and sealing materials for high-temperature industrial kilns.
Why chooes us?
Zinfon Refractory - Source control, impeccable quality of raw materials
Geographical Advantage
As a local enterprise rooted in Yingkou, Liaoning Province, we have established a comprehensive control system from mining to raw material screening, relying on the rich and high-quality magnesite resources in the surrounding area.
Rigorous Testing Of Ingredients
All raw materials used in the production of electrofused magnesia, refired magnesia, medium-grade magnesia, and high-purity magnesia undergo stringent compositional testing (MgO content, impurity indicators, etc.) to ensure that product performance problems caused by raw material defects are avoided at the source.
Owned Crushing Line
Our stable raw material supply base not only guarantees continuous production capacity but also maintains product quality at the leading level in the industry.
7*24 hours online response
Provide professional after-sales protection
Our address
Qinghua Management Dist., Dashiqiao City, Yingkou City, Liaoning, China
Phone Number
+8613700131695
+8618540210631
info@zinfon-refractory.com
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