In an integrated steel plant, which furnace typically consumes the maximum tonnage of refractory annually due to severe cyclic service and frequent hot repairs?

Introduction / Context:
Refractory consumption varies across units in an integrated steel plant. While large vessels like blast furnaces hold enormous linings, their campaigns are long. Other furnaces, subjected to rapid cycling and frequent door/roof operations, can consume more refractory per year due to ongoing hot repairs and replacements.

Given Data / Assumptions:

• We consider typical historical integrated works with soaking pits for ingot re-heating.
• Consumption metric is annual tonnage of refractory used (repairs plus relines).
• Service involves severe thermal cycling and mechanical abuse.

Concept / Approach:
Soaking pits undergo repeated opening/closing, rapid heating of cool steel, and exposure to oxidizing flames and scale. Thermal gradients and abrasion lead to frequent patching and brick replacement. Therefore, despite the massive size of a blast furnace, the annual refractory consumption of soaking pits is typically higher because of the intense, repetitive service and short maintenance intervals.

Step-by-Step Solution:
Compare service conditions: cyclic shock and mechanical wear in soaking pits vs. long blast-furnace campaigns.Relate frequent maintenance cycles to cumulative annual consumption.Conclude that soaking pits consume the most refractory annually.

Verification / Alternative check:
Classical steel-plant statistics and training materials often cite soaking pits among the highest consumers of refractory tonnage due to their duty cycle and repair frequency.

Why Other Options Are Wrong:
Blast furnace: huge lining but long campaigns reduce annual turnover.LD converter / EAF: significant consumption but often below soaking pits historically.Coke ovens: large total lining, yet long rebuild intervals.

Common Pitfalls:
Focusing on vessel size instead of service cyclic severity.Ignoring repair frequency as a driver of annual consumption.

Final Answer:
Soaking pit