The underlying of blast furnace is made of

Options

A. Graphite bricks
B. Silica bricks
C. Basic briks
D. Fireclay brickes

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure of a Blast Furnace:**
- A blast furnace is a large structure used for smelting iron ore to produce iron. It operates at high temperatures and requires materials that can withstand these conditions.

2. **Identifying the Materials Used:**
- The inner lining, or underlying, of a blast furnace must be made from materials that are highly resistant to heat and do not melt easily.

3. **Evaluating the Options:**
- The options provided include:
- Graphite bricks
- Silica bricks
- Basic bricks
- Fireclay bricks
- Each of these materials has different properties in terms of heat resistance and chemical stability.

4. **Selecting the Correct Material:**
- Among the options, fireclay bricks are known for their high refractory nature, meaning they can withstand high temperatures without melting. They are primarily composed of silica and alumina, making them suitable for the harsh conditions inside a blast furnace.

5. **Conclusion:**
- Therefore, the underlying of the blast furnace is made up of **fireclay bricks**.

**Final Answer:**
The underlying of the blast furnace is made up of fireclay bricks.

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