Question

In sponge iron technology, the percentage of iron as part of the whole iron existing as metallic iron is called 0.4pt

• A. Degree of reduction
• B. Degree of metallisation
• C. Percentage reduction
• D. Degree of oxidation

Hint:

For DRI/Sponge Iron, remember the two key quality parameters:

• Metallisation: (Metallic Fe / Total Fe). How much of the iron is now metal?

• Reduction: (Oxygen removed / Initial Oxygen). How much oxygen was taken away?

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Sponge iron, also known as Direct Reduced Iron (DRI), is produced by the solid-state reduction of iron ore. The product is not pure iron; it contains metallic iron along with some remaining iron oxides (like FeO) and gangue. A key quality parameter is to measure how much of the iron content is in the desired metallic form.

Step 2: Key Formula or Approach:
The term in question is defined by the formula: \[ \text{Degree of Metallisation (\%)} = \frac{\text{Mass of Metallic Iron}}{\text{Mass of Total Iron}} \times 100 \] where "Total Iron" includes both metallic iron (Fe) and iron present in oxides (e.g., in FeO).

Step 3: Detailed Explanation:
Let's define the terms in the options:

• Degree of Metallisation: This is the precise term for the ratio of metallic iron to the total iron content in the product, expressed as a percentage. It directly answers the question's description. A high degree of metallisation (typically $\gt $ 90%) is desired.

• Degree of Reduction: This measures the extent to which oxygen has been removed from the iron oxides in the ore. It is defined as the ratio of oxygen removed during the process to the oxygen initially present in the iron oxides. While it is related to metallisation, it is a different parameter focusing on oxygen removal rather than the final state of the iron.

• Percentage Reduction: This is a more general term and can be ambiguous. "Degree of reduction" is the standard technical term.

• Degree of Oxidation: This is the opposite of reduction and would measure the extent to which a substance has been oxidized.
The question asks for the percentage of the whole iron that exists as metallic iron, which is the exact definition of the Degree of Metallisation.

Step 4: Final Answer:
The correct term for the percentage of total iron existing in the metallic form in sponge iron is the Degree of Metallisation.