General Knowledge - Chemistry - Discussion

Can you explain metallurgical process?

calcinations is the process take place in the presence of oxygen.

Roasting is the process take place in the absence of oxygen.

According to my knowledge I think orbit is the path that electron move whereas shell is the place where electrons are present.

Smelting means concentrated ore is obtained in its melted state.

Metallurgy is process of extracting metal from their ores for that purpose ignition that is heat required after heating metal fuses that process is called smelting. In short it just a fused metal form due to heating.

Smelting is to fuse or melt (ore) in order to separate the metal contained.

Smelting is a form of extractive metallurgy; its main use is to produce a metal from its ore. This includes production of silver, iron, copper and other base metals from their ores. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gasses or slag and leaving just the metal behind. The reducing agent is commonly a source of carbon such as coke, or in earlier times charcoal. The carbon (or carbon monoxide derived from it) removes oxygen from the ore, leaving behind elemental metal. The carbon is thus oxidized in two stages, producing first carbon monoxide and then carbon dioxide. As most ores are impure, it is often necessary to use flux, such as limestone, to remove the accompanying rock gangue as slag.

Plants for the electrolytic reduction of aluminium are also generally referred to as smelters. These do not melt aluminium oxide but instead dissolve it in aluminium fluoride. They normally use carbon electrodes, but novel smelter designs use electrodes that are not consumed in the process. The end product is molten aluminium.

What is calcination?

If the ore is not oxide and found as carbonate or sulphide then it is subjected to calcination.

Calcination is process of heating carbonate ores in absence of oxygen.

Eg: CaCO3 gives on calcination CaO +CO2.