Laser Tech Solution to Urban Mining
A high-tech process that promises to dismantle obsolete electronic devices in order to recover useful raw materials is set to be an essential part of what is termed ‘urban mining’.
At the moment millions of new mobile phones, tablets and laptops are produced each year, with the vast majority relying on fresh raw materials for their construction.
The already-refined materials contained in the vast numbers of broken and obsolete devices in large part end up in landfill – a tremendous waste of often valuable materials.
While the European Union, for example, does have a recycling scheme for such devices, it is in effect a rather crude process that concentrates on bulk material flow solutions, where old phones are shredded and melted down. The focus is primarily on retrieving precious metals such as copper, gold and silver, but other rare materials vital for components are discarded as they are deemed too difficult to recover.
“Elements such as tantalum and tungsten, or rare earths such as neodymium, will continue to play an important role in the industrial manufacture of high-tech electronics,” explained Prof. Reinhard Noll from the Fraunhofer Institute for Laser Technology (ILT) in Aachen, Germany.
He is coordinating a study that is developing a laser-based process to improve recycling. He added: “Our new reverse production approach will ensure that we fully exploit the potential that so far has gone untapped.”
The project, called ADIR, has been developing special machines for automated disassembly and removal of components. They combine laser technology, robotics, modern image processing and information technology at different stages of the process.
The aim is to be able to disassemble two mobile phones a minute, and then automatically identify valuable components and desolder them using lasers.
Scientists at Fraunhofer ILT first optimised individual process steps for sorting components and further processing after each stage on a laboratory scale, and are now developing suitable software and hardware modules that can be combined to form a machine. In 2018, the project partners plan to build a demonstrator in a recycling plant to enable an experimental validation in an industrial setting. Efficiency and a high level of usability are top priorities.
The reclamation of valuable metals from electronic waste is known as urban mining and is part of a circular economy. By reusing rather than dumping materials environmental pressures are reduced, including CO2 emissions from mining and refining processes.
It also can be achieved at a predictable cost in contrast to the price of freshly mined materials, which can fluctuate from week to week.