Abstract

Energy efficiency improvements as well as energy savings are the major concern in most of the developed countries all over the world. Furnace is the most common and important part in metal industries. The useful concept of energy and exergy utilization is analyzed to investigate the energy and exergy efficiencies, energy and exergy losses, energy savings and cost benefit of an annealing furnace. The energy and exergy efficiencies of combustor and annealing chamber of the furnace have been analyzed as well. The exergy efficiency of the combustor is found to be 47.1%. The energy and exergy efficiencies of the annealing chamber are found to be 17.7 and 12.9% respectively. The overall energy and exergy efficiencies of the furnace are found to be 16.7 and 7.3% respectively. It is found that the annealing chamber is the major contributor for exergy destruction of about 57% followed by combustion chamber of the annealing furnace. By using a heat recovery system from the flue gas, about 8.1% of fuel can be saved within the payback period of less than 2 months.

Key words: Energy, exergy, efficiency, furnace.