The extraction and mining processes for gold and molybdenum have distinct techniques, given their different physical and chemical properties. Here is a summary of each:
Exploration and Discovery: Geological surveys, sampling, and drilling are conducted to locate deposits of gold.
Mining Methods: Depending on the deposit, either open-pit or underground mining techniques are employed.
Ore Extraction: The gold-bearing rock is extracted using explosives and heavy machinery.
Crushing and Grinding: The ore is crushed and ground to release the gold particles.
Concentration: Several methods can be used to concentrate the gold:
Leaching: The concentrated ore is treated with chemicals to dissolve and separate gold.
Carbon Adsorption: Gold is absorbed onto activated carbon particles.
Electrowinning or Merrill-Crowe Process: The gold is stripped from the carbon and concentrated into dore bars.
Refining: The dore bars undergo further processing to remove impurities and achieve high purity gold.
Exploration and Discovery: Geologists perform surveys and drilling to locate molybdenum deposits, often found in porphyry deposits alongside other metals like copper.
Mining Methods: Open-pit mining is commonly used, especially when molybdenum is a by-product of copper mining.
Ore Extraction: Earthmoving equipment, blasting, and drilling are used to extract the ore.
Crushing and Grinding: The ore is crushed and ground to break the rock and release molybdenum minerals.
Flotation: Flotation techniques are utilized to selectively separate molybdenum from other minerals.
Roasting (if needed): Depending on the purity and market requirements, the molybdenite concentrate may be roasted in furnaces to produce molybdenum oxide.
Hydrometallurgy: Sometimes, ore is processed via chemical methods to dissolve and purify the molybdenum.
Reduction: Molybdenum oxide is reduced using hydrogen gas or carbon to obtain pure molybdenum metal.
Refining: Further refining processes may be applied to achieve high-purity molybdenum.
Each step in the mining process is crucial to efficiently and safely extract and process these valuable minerals.