Recycling non-ferrous metals plays a significant role in reducing carbon footprint in the environment. It is cheaper to recycle non-ferrous metals, such as aluminium, silver, copper and nickel, since they can undergo unlimited recycling cycles and retain their intrinsic properties. That said, non-ferrous metals do not always come in their purest form when delivered to a recycling plant. Most metals are mixed with all manner of liquids and solid waste, making recycling efforts problematic. However, it is easy to extract and recycle non-ferrous metals from various mixtures using the right technique. This article highlights the most common processes that recyclers use to extract non-ferrous metals for reuse.
Electro-Extraction
It is the most common non-ferrous metal recycling technique due to its simplicity. The process involves applying electric current to a metal solution, which is cost-effective compared to heating. As heaps of metal waste containing a mixture of everything arrive at a recycling plant, they are mixed with a liquid solution to loosen impurities sticking on the surface. It is followed by passing an electric current via a cathode and an anode into the solution, which charges non-metallic components instantaneously. Charged non-ferrous metals in the solution are subsequently attracted to the cathode's surface, forming a thin layer. The process results in the accumulation of non-ferrous metal at the cathode, which is extracted for reuse.
Precipitation
It is another widely used recycling technique used to recover non-ferrous metal from waste. The process entails two steps: co-precipitation and adsorption. The first phase raises the pH of the aqueous solution containing non-ferrous metal waste by adding additives, such as sodium and calcium hydroxides. As the pH raises, an insoluble material referred to as precipitate begins to form. Once all the soluble metals have turned into an insoluble precipitate, they are extracted through a sieve for reuse.
Metal Sensors
Used metals arriving in metal recycling plants in solid mixtures are sorted and graded using specialised sensors. The components work by detecting elemental composition in different metals, ensuring maximum extraction of all kinds of non-ferrous metals in a waste heap. It explains why metal sensors are widely used in sorting stations in technologically-advanced recycling plants. Non-ferrous metal sensors are used together with hyperspectral cameras and robotic arms for faster and accurate identification, sorting and picking. They are particularly useful in recycling plants that receive thousands of tonnes of metal waste. However, sensors are pricey compared to other non-ferrous metal extraction techniques.
Share
