Enhancing Sustainability Through Waste Heat Utilization: A Study of Brazing Furnace Heat Recovery

Abstract

Addressing the growing concerns regarding climate change necessitates the decarbonization of energy sectors globally. Heating is the largest energy end-use, accounting for almost half of the total energy consumption in most countries. By partially substituting the use of primary energy sources with waste heat recovery, climate and environmental goals in the future will be more attainable. Industrial processes, such as brazing, generate significant waste heat, which is often released into the environment. This study investigated the feasibility of recovering and repurposing waste heat from a brazing furnace for drying applications. A case study was conducted at a manufacturing facility in which a custom heat recovery system was integrated with a continuous conveyor brazing furnace. The system captures exhaust gases (400–500°C) via a heat exchanger, transferring thermal energy to a drying chamber. Experimental data revealed that 65–70% of waste heat was recovered, reducing the energy consumption of the drying unit by 30% and lowering annual CO₂ emissions by 120 metric tons. The industry utilizes waste heat from the brazing furnace to dry the parts in the washing machine. Economic analysis indicated a payback period of 18 months. This study demonstrates the technical and economic viability of waste heat recovery (WHR) in industrial settings, promoting energy efficiency and sustainability.