Economical Preheating Furnace Improves Safety

Most smelters add cold aluminium metal to the charge of molten aluminium in the casthouse furnaces. This metal may be in the form of sows, pure offcuts, or other scrap arisings.

Such metal is frequently stored outdoors and can be wet. Charging of damp aluminium to hot furnaces results in the generation of large volumes of steam, and can cause steam explosions, in the worst cases blasting molten aluminium around the casthouse.

Traditionally, scrap metal has been heated with a gas flame to remove moisture, but such localised heating can never fully remove water, and steam explosion can still occur.

VHE has completed the fabrication and installation of a preheating furnace for the Rio Tinto Alcan smelter at Straumsvík in Iceland. The furnace, which is semi-automatic, is able to heat 15 tonnes of scrap to 200°C within 2 hours. At this temperature all water and many low-boiling point organics are fully removed. The oven is electrically heated and uses the recirculating air principle for best efficiency.

The VHE preheating furnace is economical in use and is priced to offer an excellent return on investment, with a short pay-back period.

Velaverkstaedi Hjalta Einarssonar - VHE is a major mechanical fabricator, offering a comprehensive range of design, manufacturing and site services. VHE now provides all Stimir solutions to the primary aluminium industry, with particular focus on the Rodding Plant. All aspects of design and fabrication are undertaken at VHE’s own facilities, ensuring total quality control and on-time delivery.

For further information visit www.vhe.is and www.stimir.com

VHE Scrap Preheating Furnace at Rio Tinto Alcan smelter at Straumsvík, Iceland

Based on VHE information