Introduction
kyanite is a natural refractory mineral with high refractoriness and high volume expansion at high temperatures. Parallel stripes appear on the crystal surface. Its color is light blue, cyan, bright gray, or white. It belongs to the high-aluminum mineral category.
With strong chemical corrosion resistance, mechanical strength under thermal shock, and irreversible thermal expansion, it serves as a primary raw material for the production of unshaped refractories, electric furnace roof bricks, phosphate unburned bricks, mullite bricks, and low-creep bricks.
Due to the characteristics of blue crystalline minerals, it is used to manufacture high-grade refractory materials, refractory mortar, cement, casting-resistant products, plastic ramming mixes, technical ceramics, automobile engine spark plugs, insulators, ball mill balls, test vessels, shock-resistant items, and more.
Specification: 40–80 mesh, 80–120 mesh, 325 mesh, etc.
Packing: 20-kg bags, 50-kg bags, 1-ton packages. Customized packaging is available.
Advantage
High fire resistance, good thermal shock resistance, moderate cost, and phase-change expansion that improves the structural stability of the material.
Basic Properties
Chemical Composition: The main component is aluminum silicate (Al₂O₃·SiO₂), containing approximately 63.1% Al₂O₃ and 36.9% SiO₂.
Physical Properties: Blue-gray crystals at room temperature. Refractoriness reaches 1810–1850 °C. At high temperatures (1100–1650 °C), it transforms into mullite and fused silica, with a volume expansion of 16–18% to compensate for material shrinkage.
Process
Beneficiation and Purification
After mining, the raw kyanite ore needs to be crushed and screened to remove impurities (such as Fe₂O₃, TiO₂, etc.). Magnetic separation, flotation, re-election, and other techniques are then used to further separate and enrich the Al₂O₃ content, ensuring that the purity of the raw materials meets refractory production standards.
Calcined Processing
Raw kyanite: Directly used in unshaped refractory materials (such as castables). Its phase-change expansion compensates for material shrinkage, but the amount of additive (5%–15%) must be controlled to avoid excessive expansion and cracking.
Calcined kyanite: When calcined at high temperatures of 1300–1500 °C, the kyanite completely transforms into mullite and fused silica. After volume stabilization, it is used to manufacture high-grade refractory bricks, prefabricated parts, and other products.
Deep Processing and Modification
By adding nanoscale additives such as SiC and ZrO₂, or by compositing with erythrite, silica, and other minerals, the thermal shock resistance, slag resistance, and mechanical strength of kyanite can be optimized to meet the demands of extreme working conditions.
Application
Iron and Steel Industry: Used in blast furnace body bricks and ladle linings to resist ferro erosion, and for filling brick joints through expansion.
Cement Industry: Suitable for the high-temperature zone of rotary kilns, with resistance to alkaline kiln ash erosion, such as kiln mouth guard bricks.
Glass Industry: Used for lattice bricks in heat storage chambers, offering corrosion resistance against molten glass and thermal stability.
Amorphous Materials: Used as aggregates in castables, utilizing expansion properties to enhance crack resistance.
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
Hot Tags: kyanite, China kyanite manufacturers, suppliers, factory, china aluminum, raw aluminum, silicon carbide manufacturers, silicon carbide china, china silicon carbide, bauxite and aluminum