🏭 Energy Consumption Breakdown by Process Stage
Melting Stage (60% – 80% of total energy)
Gas-Fired Furnaces: Approximately $110\text{ – }130\text{ m}^3\text{/ton}$ of rock wool, or coke consumption exceeding $350\text{ kg/ton}$.
Electric Furnaces: Approximately $900\text{ – }1400\text{ kWh/ton}$.
Curing Oven Stage (15% – 25% of total energy)
Operating temperatures typically range from $200^\circ\text{C}$ to $250^\circ\text{C}$. These systems generally utilize natural gas or leverage waste heat/flue gas recovery from the melting furnace. Energy consumption is equivalent to approximately $15\text{ – }30\text{ kgce/ton}$ (kilograms of coal equivalent per ton).
Fiberization & Collection Stage (2% – 10% of total energy)
Driven primarily by high-power centrifuges (rated at several hundred kW) and collection fans. Depending on production capacity, the single-line load ranges from $200\text{ to }600\text{ kW}$.
Cutting, Packaging & Environmental Control (Approx. 5% of total energy)
Consists mainly of motor-driven mechanical systems and dust collection/filtration units.
💰 Key Factors Influencing Operational Expenditures (OPEX)
Electricity vs. Gas Pricing: Electric furnaces emit zero direct combustion emissions, offer precise temperature control, and yield superior fiber quality. However, they require a stable, high-capacity power grid and are highly sensitive to electricity tariffs. Conversely, gas-fired furnaces are more cost-effective in regions with affordable natural gas infrastructure.
Production Scale & Capacity: Production lines with an annual output of 30,000 to 50,000 tons exhibit higher specific energy consumption compared to high-capacity 100,000-ton lines. Larger-scale operations more effectively dilute the fixed energy baseloads of curing ovens and auxiliary equipment.
Waste Heat Recovery (WHR): Utilizing waste heat from curing oven exhaust and furnace flue gas can reduce overall gas or electricity consumption by $10\%\text{ to }20\%$.
Raw Material Mix (Batch Composition): Incorporating blast furnace slag into the batch lowers the melting temperature, providing significant energy savings compared to processing 100% pure basalt.