Ore classification introduction

Ore classification

The main raw material for obtaining metals is ore.

According to the chemical composition, ores are divided into:

1. 
   native, in which metals are present in a free state (gold, silver, copper, platinum);
   
2. 
   oxidized, in which metals are in the form of oxygen compounds, carbonates or hydrates ( Fe ₂ O ₃ , PbCO ₃ , Al ( OH ) ₃ );
   
3. 
   sulfide ( PbS , Cu ₂ S , NiS ), in which metals are in the form of sulfur compounds.
   

The ore is heterogeneous in structure and consists of the following minerals:

1. 
   ore minerals of the first base metal;
   
2. 
   ore minerals of other base metals (polymetallic ores): for example lead-zinc or copper-nickel ores;
   
3. 
   minerals are satellites of the main ore minerals (gold, silver, rare and trace metals), located separately or in solid solutions with the main metals. For example, a constant satellite of nickel is cobalt, sometimes platinum and platinum group metals: satellites of lead and zinc are cadmium, indium, thallium and other rare metals;
   
4. 
   the bulk of the ore is waste rock (containing no metals), consisting of quartz, silicates, aluminosilicates and other complex minerals.
   

When processing ore, it is necessary to fully utilize its valuable components.
At many metallurgical plants, 10-15 metals are extracted, not only the main ones, but also satellite metals. As well as other valuable components (sulfur, phosphorus, etc.).
In accordance with the division of metals and source ores, metallurgy of ferrous and non-ferrous metals is distinguished.

Classification of metallurgical processes

Depending on the type of energy used in the main processes, pyrometallurgy, hydrometallurgy and electrothermal method are distinguished.
In pyrometallurgy, metals and alloys are obtained and refined by burning fuel, exothermic reactions, electric smelting, electrolysis of melts, distillation (reduction of metals in a gaseous state followed by condensation), thermal dissociation from volatile compounds, and metallothermy. The most common method in pyrometallurgy is smelting, which is based on burning fuel in furnaces. The starting material for smelting is called the charge. The charge includes fuel, ores, metals in the form of scrap, fluxes, and slags from previous smelting.
In hydrometallurgy, metals are obtained from ores by leaching and separation from solutions without heating to high temperatures.
Electrothermal method - production of metals by electrolysis of molten salts (oxides) and solutions
Fuel: coal, coke, fuel oil, natural gas.
Refractory materials are materials used for lining furnaces.
Requirements for refractory materials are high softening temperature and chemical resistance. Refractory materials are made from mineral raw materials and used in the form of bricks. They are used for laying walls, hearths and roofs of furnaces, as well as for generators, chimneys, conveyors, buckets, etc.
According to their chemical properties, refractories are divided into: acidic, basic and neutral.
Acidic - consist mainly of silica SiO ₂ ; they react chemically with basic refractories and slags, but are resistant to acidic slags.
Basic - consist predominantly of basic oxides ( MgO and CaO ).
Neutral - almost do not interact with either basic or acidic refractories and slags (x -romite and carbon refractories).