What powders can be calcined in a high-temperature rotary furnace?

The high-temperature rotary furnace, with its advantages of uniform heating, multi atmosphere compatibility, and continuous production, can calcine a wide range of powders, covering key materials in the fields of metal, non-metal, ceramic, composite materials, and environmental protection. The following are specific classifications and typical applications:

1. Metal powder
Nonferrous metal oxides
Zinc oxide (ZnO): obtained by calcining zinc concentrate (ZnS) for desulfurization, used in fields such as rubber, ceramics, cosmetics, etc.
Aluminum oxide (Al ₂ O3): Two stage calcination (950 ℃ dehydration+1250 ℃ crystal transformation) is used to prepare high-purity α – Al ₂ O3 for wear-resistant ceramics and electronic substrates.
Copper oxide (CuO): calcined copper ore or copper hydroxide, used as a catalyst, pigment, and battery material.
iron-based powder
Reduced iron powder: Calcination of iron oxide (Fe ₂ O ∝/Fe ∝ O ₄) in a hydrogen or carbon monoxide atmosphere, used for powder metallurgy and welding materials.
Ferric oxide (Fe ∝ O ₄): calcined iron salt solution or iron hydroxide, used for magnetic materials, pigments, and catalysts.
Rare metals and alloys
Titanium alloy powder: High purity titanium powder is obtained by calcining titanium hydride (TiH ₂) and dehydrogenation in an inert atmosphere, which is used for aerospace and biomedical implants.
Nickel cobalt alloy powder: calcined laterite nickel ore or hydroxide precursor, used as positive electrode material for lithium batteries (NCM/NCA).

2. Non metallic mineral powder
Ceramic raw materials
Kaolin: Calcination (600-900 ℃) to remove crystal water and obtain metakaolin, which is used as a whitening agent in papermaking, coatings, and ceramics.
Diatomaceous earth: calcined (500-800 ℃) to remove organic impurities and increase porosity, used for filtering materials and insulation materials.
Quartz sand: High temperature calcination (1200-1500 ℃) achieves crystal transformation (α – quartz → β – quartz), improves heat resistance, and is used for glass and ceramic glazes.
chemical raw materials
Calcium carbonate (CaCO3): Calcined at 800-900 ℃, it decomposes into calcium oxide (CaO) and carbon dioxide, and is used as a filler in building materials, rubber, and plastics.
Calcium phosphate (Ca ∝ (PO ₄) ₂): calcining animal bones or minerals to obtain bioactive ceramic materials for orthopedic implants.

3. Ceramic and refractory powder
Advanced Ceramics
Silicon nitride (Si ∝ N ₄): Silicon powder is calcined in a nitrogen atmosphere to obtain high-strength, high-temperature resistant ceramics, which are used in bearings and cutting tools.
Silicon carbide (SiC): A mixture of calcined silica and carbon powder is used to obtain wear-resistant and corrosion-resistant ceramics for grinding wheels and semiconductor devices.
Zirconia (ZrO ₂): Calcined zircon (ZrSiO ₄) or zirconium hydroxide to obtain stabilized zirconia, used in oxygen sensors and dental restorative materials.
refractory material
Magnesia (MgO): Calcine magnesite (MgCO3) to obtain high melting point refractory raw materials, which are used for steel smelting furnace lining.
Chromium iron ore sand (FeCr ₂ O ₄): calcined to improve fire resistance, used for casting sand molds and glass melting furnaces.

4. New energy material powder
Lithium battery materials
Positive electrode material precursor: calcining nickel cobalt manganese hydroxide (NCM/NCA precursor) to obtain lithium-ion battery positive electrode material, improving energy density.
Lithium iron phosphate (LiFePO ₄): calcining a mixture of ferrous oxalate and lithium dihydrogen phosphate to obtain a high safety positive electrode material.
Hydrogen based materials
Hydrogen storage alloy powder: calcining rare earth nickel alloy (such as LaNi ₅) to adjust lattice parameters and optimize hydrogen absorption performance, used for hydrogen fuel cells.
Catalyst carrier: calcined alumina or titanium dioxide carrier, loaded with precious metals such as platinum and palladium, used for electrolysis of water to produce hydrogen.

5. Environmental Protection and Solid Waste Treatment Powder
Hazardous waste disposal
Fly ash: calcined (800-1200 ℃) to solidify heavy metals (such as Pb and Cd), reduce the toxicity of leachate, and used for roadbed materials.
Sludge: Calcination (500-800 ℃) to remove organic matter and obtain harmless ash residue for brick and tile manufacturing.
Utilization of industrial by-products
Steel slag: Calcination (1000-1300 ℃) activates cementitious activity and replaces some cement in concrete.
Fly ash: calcined (700-900 ℃) to enhance volcanic ash activity, used for geopolymer materials.

6. Special functional powder
magnetic materials
NdFeB: Calcination of neodymium, iron, and boron metal powders to obtain strong permanent magnet materials for use in motors and headphones.
Ferrite (MFe ₂ O ₄, M=Mn/Zn/Ni): Calcined metal oxide mixture to obtain soft or hard magnetic materials, used in transformers and magnetic recording media.
optical material
Fluorescent powder: calcining rare earth oxides (such as Y ₂ O ∝: Eu ³ ⁺) to obtain luminescent materials for LED and display applications.
Transparent ceramics: Calcined high-purity alumina or yttrium oxide to obtain ceramics with a light transmittance of>90%, used for high-pressure sodium lamps and laser windows.

7. Biomedical powder
Bioceramics
Hydroxyapatite (HA, Ca ₁₀ (PO ₄) ₆ (OH) ₂): Calcined calcium phosphate and calcium hydroxide to obtain bioactive ceramics for bone repair and dental implants.
Bioglass: calcining a mixture of sodium silicate, calcium phosphate, and other materials to obtain biodegradable bone repair materials.
drug carrier
Mesoporous silica: Calcination of silicon source (such as ethyl orthosilicate) and template agent to obtain a high specific surface area carrier for controlled drug release.