Life cycle assessment of metal heat treatment process using furnaces with different energy sources in China from multiple perspectives: environmental impact, power structure and production cost

Heat treatment is an energy intensive manufacturing process to achieve the desired organization and properties. To address the growing demand for clean and cost-effective energy, natural gas has gradually replaced electric energy in processes, and industrial gas furnaces have become widely adopted. However, the environmental impact of resistance furnaces and industrial gas furnaces remains uncertain. This study offers a comprehensive analysis of life cycle assessment of metal heat treatment process using furnaces with different energy sources from multiple perspectives: environmental impact, power structure and production cost. In this work, through the life cycle assessment method, the results indicate that the environmental impact of the former is greater than the latter. Then, the results of environmental impact under different power structures are further studied, and are tended to choose clean energy as production power as possible. Furthermore, production cost of electricity and gas is analyzed by combining the factors of regions, seasons, and periods. The verification shows that within a certain cost range, the industrial gas furnace of metal heat treatment process can be promoted to reduce environmental impact. This work provides a targeted method for comprehensive assessment of the resistance furnace and industrial gas furnace metal heat treatment process, to further explore the applications of green energy in green manufacturing process.