Specific energy consumption of furnaces is very useful for comparing with design values or best practical norms.
There are many factors affecting furnace specific energy consumption such as capacity utilization of furnaces, final heating temperature, use of inefficient burner, excess air ratio, improper insulation/refractories, high stack loss etc... Specific energy consumption test is the key for assessing current performance of furnaces and finding the scope for improvements and productivity.
Specific Energy Consumption
= Amount of Energy consumed in Kcal/hr / Quantity of material processed, Ton/Hr
If Amount of fuel consumed is 370 Kg/hr and amount of billet processed is 6 Ton/hr..
Then Specific fuel consumption of furnace
= Amount of fuel consumed in Kg/hr / Amount of billet processed in Ton/Hr
= 380/6
Specific fuel consumption = 63.33 Kg of fuel/ tonne of billet