Energy- and exergy-based analysis for reducing energy demand in heat processes for aluminum casting

In this paper, energy- and exergy-based analysis is used to analyze a factory with high energy demand for the production of aluminum discs. The analysis is focused on heat processes that take place in a melting furnace, a casting machine, a heat treatment oven, and a drying oven. Energy and exergy efficiencies are computed to assess the room for the improvement of the energy efficiency processes. The analysis shows that a large amount of energy is lost due to heat losses to the environment, and solutions for reducing energy demand and emissions have been identified. Instead of changing the equipment of a factory, significant improvements and consequent reduction of fossil fuels consumption can be obtained by increasing the thermal insulation of some components and by means of waste heat recovery performed by heat exchangers, with a consequent energy demand reduction of 15%.