Pyrometallurgical extraction of metals requires large amount of energy as shown in the following table: (The following values are approximates and the exact value can be seen in reference given at the end of this lecture)
Metal
Gross energy
Requirement (mj/kg metal)
Titanium
360
Aluminium
220
Nickel
110
Zinc
50
Copper
40-50
Steel
15-20
Metal grade of the ore is important. Low grade ore will consume more energy. Additional energy is required for mining and mineral processing to remove gangue mineral.
This is particularly true for copper and nickel extraction: for example 0.5% Cu grade of ore will consume 250 Mj/kg of energy which will decreases to 50 MJ/kg when copper grade of ore is 2%. Similarly a nickel grade of 0.5% will require 375 MJ/ kg energy which will decrease to 150 MJ / kg when nickel grade is 2%. Metal grade of ore is very important.
