difference between calcination and roasting
Answers
Answer:
roasting is the process of converting sulphide ores to their oxides. calcination is the process of converting carbonate ores to their oxides
Answer -
Calcination - As per the popular definition, calcination is defined as the process of converting an ore into an oxide by heating it strongly. The ore is heated below its melting point either in absence of air or in a limited supply. This method is commonly used for converting carbonates and hydroxides to their respective oxides. During calcination, moisture and volatile impurities are also removed. Calcination can also be described as a thermal process that is used to convert yores and other solid materials by bringing about thermal decomposition. In calcination, reaction most of the time occurs at or above the thermal decomposition temperature.
Roasting - When we talk about roasting, it is basically a process of metallurgy where an ore is converted into its oxide by heating it above its melting point in the presence of excess air. While calcination is mostly used in the oxidation of carbonates, roasting is a method that is used for converting sulphide ores. During roasting, moisture and non metallic impurities in the form of volatile gases are released. Process of roasting consist of solid-gas thermal reaction which includes oxidation, reduction, sulfation, chlorination and pyro hydrolysis