Feasibility of a District Heating System in Fjardabyggd Using Waste Heat from Alcoa Fjardaal

Abstract

The Alcoa Fjarðaál smelter in Iceland consumes 4600GWh annually to produce aluminum. About 50% of the total energy absorbed by the cells is reduced to waste heat of which roughly 40% is currently lost through exhaust gases. The exhaust gases leave the cells at about 110°C before entering the gas treatment center (GTC). The feasibility of operating heat exchangers upstream of GTCs has been demonstrated at other smelters. Reyðarfjordur, which is 5.5km from Fjarðaál currently uses electricity for domestic heating, like other surrounding communities. Previous research has shown that the waste heat from Fjarðaál is more than enough to supply space heating for the local community. This paper will address the technical challenges and suggest solutions to deliver heat in a closed-loop heating circuit from the Fjarðaál plant to Reydarfjordur and estimate the total investment cost for the heat regeneration system.