Leaching is a chemical process used in mining to extract valuable minerals from ore by dissolving them in a solution. Below are key terms commonly associated with leaching:
- Leaching: The chemical process of extracting minerals from ore by dissolving them in a solvent, often acid or cyanide solutions. It can also occur naturally when groundwater dissolves minerals.
- Heap Leaching: A process where crushed ore is piled on an impermeable pad and irrigated with a leach solution (acid or alkali) to dissolve metals, which are then collected for recovery. Commonly used for copper, nickel, uranium, and precious metals.
- In-situ Leaching (Solution Mining): Extraction method where leaching solutions are injected directly into the ore deposit underground through drilled holes, dissolving minerals which are then pumped out for processing. Used mainly for copper and uranium.
- Solvent Extraction and Electrowinning (SX/EW): A two-stage hydrometallurgical process where copper ions are first extracted from leach solutions into a solvent and then recovered as pure copper cathodes by electrowinning.
- Tailings: The residual material left after leaching or milling, containing waste rock and residual chemicals.
- Leach Solution: The chemical solution (acidic, alkaline, or cyanide-based) used to dissolve the target minerals during leaching.
- Roasting: Pre-treatment of ore involving heating to remove carbonaceous material that might hinder leaching efficiency.
- Acid Leaching: Leaching using acid solutions, often sulfuric acid, to extract metals like copper and uranium.
- Cyanide Leaching: Use of cyanide solutions to dissolve precious metals such as gold.
- Leach Pad: The lined area where heap leaching takes place, designed to collect leachate for processing.
- Extraction: The removal of valuable metals from the leach solution, often by solvent extraction or electrowinning.
These terms form the foundation of understanding the leaching process in modern mining operations.
From “lixiviant” to “pregnant leach solution,” the terminology in leaching processes can be quite specific! Which leaching term do you find most fascinating, or perhaps, most challenging to explain to others? Share your insights!
Text rights:(Leaching – Mining Fundamentals, n.d.)
Text source: Leaching—Mining Fundamentals. (n.d.). Retrieved June 3, 2025, from https://www.azomining.com/Article.aspx?ArticleID=1227
