Afrox is consulting with several key players in the South African aluminium industry with a view to introducing an innovative new optimised oxyfuel melting process, developed by parent company, The Linde Group.

The process delivers production improvements which lead to significant cost savings and could deliver real capacity increases in the South African aluminium sector.

Following its introduction in Europe in 2005, the new proprietary ‘low-temperature oxyfuel burner process (LTOF®)’ is achieving an average 30-50% higher melt rate and in some cases, a 100% improvement in melt rate - compared with conventional air-fuel processes.

Fuel consumption is reduced by up to 50%, flue gas volumes by up to 80% and dross formation decreased as a result of more uniform heating and melting. Carbon dioxide and sulphur dioxide emissions are also cut by up to 50% and nitrogen oxide emissions are virtually eliminated.

The Linde Group has more than 130 conventional oxyfuel installations in operation in the European aluminium sector and has used this expertise to take heating technology to the next level. February 2009 saw Stena Aluminium of Sweden become the latest company in Europe to introduce the new burner technology.

Michael Hill, Afrox’s Applications Engineer for Metallurgical Processes, is of the view that the new low-temperature oxyfuel burner process is capable of delivering real capacity increases in the South African aluminium sector - boosting productivity, saving energy and greatly mitigating environmental impact.

He explained, “Increasing the throughput of existing melting furnaces poses a real challenge for the aluminium industry. Producers must continuously increase process yields, control fuel consumption and reduce emissions of greenhouse gases. In South Africa, the primary drivers are expected to be potential cost savings associated with reduced energy consumption, and reduced dross.”

“In reverberatory furnaces, power must also be controlled so as not to overheat the refractory ‘roof’ — or exceed furnace temperature set point. The new low-temperature oxyfuel burner process makes it possible to run the furnace at full power for longer, without exceeding roof temperatures.$quot;

$quot;This is quite a breakthrough compared to conventional heating, which requires the power to be reduced as soon as the maximum set point is reached, to avoid overheating.$quot;

Afrox is able to supply a commissioning and support package on a rental basis (including a nominal technology fee) for South African companies who introduce the new process.