Heating of coke ovens in an integrated steel plant—fuel sources Coke oven heating is commonly carried out using which fuel(s)?

Introduction / Context:
Coke oven batteries require steady, controllable heating to carbonize coal into metallurgical coke. Integrated steelworks generate multiple by-product gases (coke oven gas, blast furnace gas, basic oxygen furnace gas) that can be blended to fire furnaces economically.

Given Data / Assumptions:

• An integrated plant with gas collection and mixing facilities.
• Objective: maintain the coking temperature profile across heating walls.
• Focus on typical fuels available onsite.

Concept / Approach:
Coke oven gas (COG) has high calorific value and is a prime fuel for heating the ovens. Blast furnace gas (BFG), although lean, is abundant and can be mixed ('mixed gas') with COG to achieve desired calorific value and flame characteristics. Electricity is generally not used for direct firing of coke oven heating flues.

Step-by-Step Solution:

Verification / Alternative check:
Plant energy balance diagrams routinely show COG as priority fuel for batteries and BFG as a secondary/mixed component.

Why Other Options Are Wrong:

• Electricity: not typical for this application; indirect roles limited to auxiliaries.
• BFG or COG alone can be used, but the best answer reflects common mixed-gas practice.

Common Pitfalls:
Ignoring calorific value blending; pure BFG often cannot meet flame temperature needs without enrichment.

Final Answer:
Both (b) and (c)