Step 1: Understanding the Concept:
Pig iron is the intermediate product of smelting iron ore. It has a very high carbon content (typically 3.5%–4.5%), which makes it very brittle and not directly useful for most engineering applications until it is further refined.
Step 2: Key Formula or Approach:
Match the type of iron/steel to the specific furnace used for its production:
Pig Iron $\rightarrow$ Blast Furnace
Cast Iron $\rightarrow$ Cupola Furnace
Steel $\rightarrow$ Bessemer, Open Hearth, or Electric Arc Furnace
Step 3: Detailed Explanation:
The Blast Furnace is a large, vertical structure where iron ore, coke (fuel), and limestone (flux) are reacted under a blast of hot air. The process reduces the iron oxides in the ore into molten iron. This molten metal, collected at the bottom, is "Pig Iron." It serves as the raw material for both cast iron and steel production.
Step 4: Final Answer:
Pig iron is produced in a Blast furnace.