Core Functions

• Valuable Metal Recovery: Extracts target metals (e.g., iron, copper, lead, zinc, rare earths) from tailings via high-temperature reduction or smelting.
• Harmless Stabilization: Fixes heavy metals (e.g., cadmium, arsenic, chromium) in glassy slag through melting, preventing leaching and environmental pollution.
• Resource Conversion: Converts tailings into reusable materials such as slag aggregates, cement clinker, or ceramic raw materials.
• Volume Reduction: Reduces tailings volume by 60–80% through melting and solidification, alleviating storage pressure.

Key Technical Principles

• Operates at 1400–1800°C using electric heating methods like electric arc, resistance, or induction.
• Tailings are mixed with fluxes (lime, silica, fluorite) and reducing agents (coke powder, coal dust) before entering the furnace.
• At high temperatures:
  • Organic pollutants are pyrolyzed and decomposed.
  • Metal oxides are reduced to elemental metals or alloys, which settle and separate from slag.
  • Inorganic components form stable, non-toxic glassy slag after cooling.

Common Equipment Types & Characteristics

Typical Application Processes

1. Pretreatment: Tailings are crushed, dried, and sorted to remove large impurities and adjust moisture content (≤5%).
2. Batching & Mixing: Mix tailings with fluxes and reducing agents in a specific ratio to optimize smelting conditions.
3. Electric Smelting: The mixture is fed into the electric furnace for high-temperature reaction (holding time 2–6 hours).
4. Separation & Recovery: Molten metals are tapped separately for refining; slag is cooled and crushed into building materials.
5. Gas Treatment: Flue gas is purified via dust removal, desulfurization, and denitrification before discharge.

Core Advantages & Application Scenarios

Advantages

• Strong adaptability: Handles tailings with complex components, low metal grades, or high moisture content.
• High resource utilization rate: Metal recovery rate reaches 70–95% (varies by tailing type), and slag utilization rate exceeds 90%.
• Environmentally friendly: Harmless treatment meets national emission standards, reducing land occupation and pollution risks.

Typical Application Scenarios

• Iron ore tailings: Recover iron concentrate and produce slag aggregates for road construction.
• Non-ferrous metal tailings (copper, lead, zinc): Extract target metals and convert slag into cement admixtures.
• Rare earth tailings: Recover rare earth elements and stabilize radioactive substances.
• Coal gangue (coal mining tailings): Generate electricity via combustion and produce coal gangue bricks from slag.