Explain the extraction of iron from its oxide ores.

(N/A) The extraction of iron from its oxide ores $(Fe_{2}O_{3}, Fe_{3}O_{4})$ involves the following steps:
$1$. Concentration and Calcination: After concentration,the ore is subjected to calcination/roasting to remove moisture,decompose carbonates,and oxidize any sulphide impurities.
$2$. Blast Furnace Process: The concentrated ore is mixed with limestone $(CaCO_{3})$ and coke $(C)$ and fed into a blast furnace from the top.
$3$. Chemical Reactions in Blast Furnace:
- At the top (lower temperature,$500-800 \ K$): The iron oxides are reduced by $CO$ gas.
$3Fe_{2}O_{3} + CO \rightarrow 2Fe_{3}O_{4} + CO_{2}$
$Fe_{3}O_{4} + CO \rightarrow 3FeO + CO_{2}$
- At the middle (higher temperature,$900-1500 \ K$): $FeO$ is reduced to metallic iron.
$FeO + CO \rightarrow Fe + CO_{2}$
$C + CO_{2} \rightarrow 2CO$
- Limestone decomposes to $CaO$,which reacts with silica $(SiO_{2})$ impurity to form slag $(CaSiO_{3})$.
$CaCO_{3} \rightarrow CaO + CO_{2}$
$CaO + SiO_{2} \rightarrow CaSiO_{3}$
- At the bottom (very high temperature,up to $2200 \ K$): Coke burns to provide heat and $CO$ for reduction.
$C + O_{2} \rightarrow CO_{2}$
$FeO + C \rightarrow Fe + CO$