Thermal performance enhancement of aluminum casting processes in foundry operations : a case study at Ceylon Electricity Board

Abstract

The Ceylon Electricity Board (CEB) foundry plays a vital role in Sri Lanka’s energy sector by producing aluminum components for the national grid. However, reliance on outdated sand casting methods and inefficient oil-fired furnaces has led to low energy efficiency, high operational costs, and environmental concerns. This study addresses these challenges by designing and implementing a waste heat recovery system integrated with a welded plate heat exchanger to enhance energy efficiency and optimize foundry operations. The research evaluated the performance of existing furnaces, revealing significantly low Specific Fuel Consumption (SFC) compared to the initial fuel consumption values , with the pit furnace operating performing at 0.681 l/kg and the tilting furnace operating at 0.294 l/kg. A welded plate heat exchanger was fabricated and integrated into the combustion system to preheat combustion air using exhaust gases. Computational Fluid Dynamics (CFD) simulations were employed to optimize the heat exchanger design and predict performance. Experimental results showed a 29.5% reduction in fuel consumption and a 32% decrease in melting time, with the heat exchanger achieving an energy recovery rate of 40%. The findings demonstrate the feasibility of waste heat recovery in improving thermal efficiency and reducing emissions, providing a scalable solution for small and medium-scale foundries. This study recommends further modernization, including advanced monitoring systems and renewable energy integration, to enhance sustainability. By reducing reliance on imports and promoting local production, this research aligns with Sri Lanka’s economic and environmental goals, offering a robust framework for energy-efficient aluminum casting practices.