LOWERING THE IMPACT
Our latest R&D projects mostly focus on decreasing the emission of greenhouse gases in aluminium cast houses.
Sistem Teknik builds single and multi-chamber aluminum melting/holding furnaces based on customer specifications. The capacity of the furnaces ranges from 15 to 150 tons of liquid aluminum, with melting rates of up to 20 tons per hour, and the energy consumption ranges from 500 to 700 kW/ton, depending on the application. Electro-magnetic stirrers, porous plugs, and mechanical or electromagnetic pumps (without a vortex well) are available for these furnaces. Single chamber aluminum melting/holding furnaces can be stationary or tiltable, depending on the application.
These furnaces, made of strong steel, can withstand thermal and mechanical stresses while operating in harsh foundry conditions. The furnace door is resistant to all damages, thanks to a special sealing clamp system developed as part of a year-long R&D project. The door completely opens to allow for easy cleaning, charging, and maintenance of the furnace bath.
Sistem Teknik’s aluminum melting furnaces are among the most environmentally friendly furnaces on the market, thanks to the company’s continuous development of furnace technology over the last 40 years. For clean scrap, high efficiency regenerative burners can be used, while traditional cold air burners can be used for dirty scrap. In addition, to increase the immediate O2 levels after scrap-charging, an O2 injection system can be integrated into the heating system. The furnace atmosphere pressure control system achieves low energy consumption, ensuring an environmentally friendly manufacturing process and low NOx values.
More Information on Multi-Chamber Technology
Depending on the type of scrap and the method of furnace charging, multi-chamber melting furnaces typically have two or three chambers. While contaminated scrap (ingots, T-bars, thick gauge scrap) is melted inside the scrap chamber, the melting chamber heats up the furnace (s). The continuous transfer of molten metal to the scrap chamber ensures temperature uniformity and the highest alloying quality. The use of a vortex well allows the furnace to process chips and small scrap.
Scrap is loaded onto the balcony of the scrap chamber in multi-chamber melting furnaces via the bottom-retracted charging machine. The chamber then pyrolyzes the scrap in a very low O2 environment for 20 to 25 minutes, depending on the scrap type and level of contamination. After the process, the pyrolyzed gas is collected and transferred to the front of the melting chamber’s main burners to be burned for extra energy. This results in a more environmentally friendly process as well as energy recovery.
While the drying/preheating chambers are critical for maintaining safety in melting operations by eliminating explosion risks, they also provide significant energy savings by utilizing waste gases from the melting furnaces. The use of recirculation fans in these chambers allows the material to be heated in 90 minutes while reaching temperatures of 150 °C. While high efficiency regenerative burners are used in the melting chamber, a cold air burner is used in the scrap chamber to adjust the O2 level in multi-chamber furnaces.