Industrial fuels – common choice for cement kilns and metallurgical heating In industrial practice, which fuel is mostly used as the primary heat source in the cement industry (rotary kilns) and widely in high-temperature metallurgical processes (e.g., furnaces and kilns)?

Introduction / Context:
Cement rotary kilns and many metallurgical furnaces demand intense, controllable heat release, clean flame characteristics, and good temperature uniformity. Selecting the right industrial fuel impacts flame temperature, kiln throughput, clinker quality, and emissions.

Given Data / Assumptions:

• Cement plants commonly fire rotary kilns requiring stable, high-temperature flames.
• Metallurgical operations (e.g., reheating and some reduction furnaces) require efficient, controllable combustion.
• Fuel should be suitable for burner injection and air–fuel mixing.

Concept / Approach:
Pulverised coal (finely ground) is pneumatically conveyed and burned through specially designed kiln burners. Fine particle size ensures rapid ignition and complete combustion, enabling high flame temperatures and good heat transfer. Its logistics, cost, and burner compatibility make it a mainstream choice in cement and many metallurgical applications.

Step-by-Step Solution:
Identify operational needs: high, controllable heat release in a continuous process.Match fuel handling: fine coal can be metered, blown, and mixed with air efficiently.Consider alternatives: coke and wood charcoal are solid lumps, less suitable for burner atomisation; fuel oil/gas are alternatives but not “mostly used” in many regions historically.Conclude: pulverised coal aligns best with typical kiln and furnace firing systems.

Verification / Alternative check:
Standard kiln burner designs, coal mills, and inline calciner systems are engineered around pulverised coal firing; retrofits may also accept petcoke or alternative fuels, but pulverised coal remains the benchmark.

Why Other Options Are Wrong:

• Coke/bituminous coke: primarily a reductant in blast furnaces; not commonly pulverised for kiln main firing.
• Wood charcoal: inconsistent supply and reactivity; not mainstream for cement kilns.
• Fuel oil only: used in some plants, but not the “mostly used” traditional choice.

Common Pitfalls:
Confusing metallurgical reductants (lump coke) with burner-grade, pneumatically conveyed fuels. Burner systems need fine, reactive fuel for flame shaping.

Final Answer:
pulverised coal