Exergy analysis and efficiency evaluation for an aluminium melting furnace in a die casting plant

An aluminium melting furnace efficiency in a die casting plant was investigated using energy and exergy methods. Energy efficiency and exergy efficiency values were evaluated for the natural gas-fired furnace, and the efficiency improvement was analyzed before and after two new regenerative burners were installed on the furnace. The research analyzed and compared the environmental impacts attributable to the melting furnace before and after the burner upgrading project, and also provided a financial analysis of the capital investment of the upgrading project. The study shows that the exergy method can be used beneficially to analyze the furnace efficiency and that exergy efficiency is a more practical measure in reality. Thus, it is believed that further applications of exergy methods are desirable to a wider range of industrial and engineering applications. From the results of comparisons, the study shows that the regenerative burner technology and stage-combustion technique can improve combustion performance, reduce fuel (natural gas) consumption and lower NOx and Co2 emissions. Adopting the regenerative burner and stage-combustion technique will be beneficial to the die casting plant on energy saving and cost reduction. Recommendations are also made for further efficiency improvements.