Recent comparison of 3 to 30 tonne aluminium capacity Monometer oxy-fuel rotary furnaces with plasma-arc alternatives, highlighted the continuing strengths of Monometer rotary furnace technology. Both achieve the high temperatures required to process aluminium scrap without salts, including oxide material; both offer high energy efficiency, and low exhaust emissions volumes; under favourable conditions, plasma-arc has demonstrated higher efficiency, yield potential, and capacity for salt-free operation than oxy-fuel. Yet, still foundry-specific considerations often lead to favouring the oxy-fuel route.
Considerations include costs, such as electrical power vs natural gas or low cost reclaimed oil, inert gas supply compared with oxygen — argon can exceed three times the price of oxygen, but also practical issues such as: maintenance and service requirements, operator training; grid power availability; process chemistry; the essential feature of full and continuous furnace rotation provided with oxy-fuel, but that the attached cables of plasma arc technology can restrict.