2015年9月20日星期日

Top 3 solutions for recycling aluminium from aluminium dross

Top 3 solutions for recycling aluminium from aluminium dross 


Aluminum dross is a natural outcome in aluminum melting, which is made by alumina, aluminum nitride, other oxides, nitrides and aluminum. 

The actual meaning of dross is "foreign matter, dregs, or mineral waste, in particular scum formed on the surface of molten metal." not trash as one answer guesses. 

When melting aluminum cans the inside plastic, paint on the outside, and thin layer of aluminum oxide is left on the surface when the aluminum metal collects below at about 1250F. This dross/slag is from 1/3 to 1/2 the weight of the cans melted in ordinary methods and it is not practical to remove the Aluminum in the oxide. Commercial processors can use electrolysis on a big enough mass of it. 

If dross is the same as trash, aluminum is not usually recovered, as recovery is labor intensive. Robots cannot separate aluminum from foil coated paper, except with very complex technology. 

The recovery rate of aluminum dross processing will greatly affect the economical benefits in recycled aluminum industry. 

Aluminum dross and aluminum slag processing 3 methods 

MRM method (Metal recycling machine), this process is sending the hot aluminum slag and aluminum dross from melting furnace to the machine with the stirrer directly, make the liquid aluminum deposited in the bottom of melting furnace, Adding heating agent into the machine to make the aluminum dross keep requested temperature. The rest aluminum slag can be further sieved, pulverized, melted and recovered for the second recovery processing. The recovery rate can be 91% and the burning rate of aluminum can be reduced to 4%.  For more information, please check aluminium dross processing machine.

The press recovery process method, Press 15Mpa pressure on it, the liquid metal of slag will flow down to the lower container under the pressure; the oxidation of slag that is pressed will be ended, the oxide will be muffled in the metal shell. At the same time, the metal shell of slag will transfer the heat to the pressure head and slag tray, the cooling water of pressure head will take away lots of heating, which will make the slag temperature reduced from more than 800 to below 450, to prevent the oxidation of metal because of high temperature. 

ALUREC Method. Rotary aluminum melting furnace, Oxygenenrichment natural gas as the fuel, can get to high temperature in a short time. Liquid aluminum lay down the bottom of melting furnace; Non-metallic slag will float on the top of melting furnace. The method is featured with high efficiency, low energy consumption, good running environment. Pure oxygen will be used as oxidizer effective to reduce the organic gases generated in the combustion process. Gas hoods can effectively recover the other dust, with high efficiency, high degree of mechanization and good running environment advantages. The shortage is the residual aluminum dross needs to be further processed. 
Aluminium recycling