Greenhouse Gas Emissions from Secondary Aluminum Foundry and Reduction Strategies

Abstract

Abstract
Aluminum is widely used in various sectors such as construction, transportation, and packaging due to its lightness, durability, and recyclability, leading to a rapid increase in global production volume. The most effective way to mitigate the environmental impacts of rising demand is to promote aluminum recycling through secondary production. Today, a significant portion of circulating aluminum is recycled, and this process is predominantly carried out by small and medium-sized enterprises (SMEs). Although the individual environmental impact of SMEs may appear limited, their large numbers and lack of effective monitoring mechanisms result in a considerable contribution to global greenhouse gas (GHG) emissions. In this study, the GHG emissions of a SME-scale secondary aluminum foundry operating in Türkiye for the year 2022 were calculated using actual operational data. A sector-specific emission factor was determined, and the environmental impacts of the production steps were evaluated based on the workflow. The total emissions were calculated as 9,645.3 tons CO₂e year^-1, with 60% attributed to natural gas, 38% to electricity consumption, and 1.1% to transportation. The facility-specific emission factor was calculated as 0.402 tons CO₂e per ton of aluminum, and it was found that the melting process accounted for 33% of total emissions. In addition, technical and operational improvement suggestions for emission reduction were presented, and the facility's production activities were evaluated within the scope of the European Union’s Carbon Border Adjustment Mechanism (CBAM).