LITHIUM EXTRACTION : GEOGRAPHY

NEWS :  Chile’s Atacama salt flat sinking due to lithium mining: What a new study says

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Lithium, also known as 'white gold', is one of the most sought-after metals on Earth. However, over the years, research has shown that lithium mining has had severe environmental fallouts, especially in countries such as Chile which are the leading producers of the metal

Lithium Extraction and Subsidence in Atacama

  • Subsidence: The Atacama salt flat is sinking by 1 to 2 cm annually, primarily in areas with active lithium extraction.
  • Mechanism: Rapid brine extraction exceeds natural aquifer recharge, causing the Earth's surface to sink.

Environmental Consequences of Lithium Mining

  • Water Scarcity: Lithium extraction via brine evaporation consumes 2,000 tons of water per ton of lithium, worsening water scarcity in the arid Atacama Desert.
  • Ecosystem Contamination: Chemicals like sulfuric acid and sodium hydroxide used in extraction contaminate soil and water, threatening local ecosystems.
  • Biodiversity Loss: A 2022 study linked reduced water levels from lithium mining to declining flamingo populations in the region.

Atacama Desert Overview

  • Driest Place on Earth: Receives less than 1 mm of rainfall per year.
  • Location: Northern Chile, between the Andes and the Chilean Coast Range.
  • High Altitude: Elevation ranges from 2,400 to over 4,500 meters.
  • Salt Flats: Home to Salar de Atacama, a major lithium source.
  • Unique Flora and Fauna: Supports species like the Andean flamingo, adapted to extreme dryness.
  • Astronomical Observatories: Ideal location due to clear skies and high altitude; houses the ALMA telescope.

Lithium Overview

  • Rechargeable Batteries: Essential for batteries in electronics and electric vehicles.
  • Symbol and Atomic Number: Represented by "Li," atomic number 3.
  • Reserves: Predominantly found in the "Lithium Triangle" (Chile, Argentina, Bolivia).
  • Lightest Metal: Lowest density of all solid elements, useful in lightweight battery applications.
  • Industrial Uses: Also used in ceramics, glass, and as a heat-resistant lubricant.

Brine Evaporation Method for Lithium Extraction

  • Collection: Lithium-rich brine is pumped from underground salt flats into evaporation ponds.
  • Evaporation: Water evaporates naturally, leaving behind concentrated lithium salts.
  • Extraction: Lithium salts are processed into lithium carbonate or hydroxide for batteries and other uses.
  • Environmental Impact: Significant freshwater usage, potential water depletion, and soil contamination.