Register for weekly alerts

Blog: is the metal's industry missing a trick?

Date: 27/02/2014 | Author: Paul Sanderson

Image for Blog: is the metal's industry missing a trick?

'Are waste handlers realising the true potential of metal?', asks Chris Oldfield. The worth of metals may be on everyone’s radar, but is there even more value to be gleaned?

There can be no disputing the significant commodity value of metals. This value is one of the reasons the Scrap Metal Dealers Act came into force in 2013 – to try to crack down on criminals’ exploitative trade of this expensive recyclate.

Yet despite the widespread acknowledgement of the monetary worth of metals, some companies are still failing to maximise their return from this area of waste handling.

The reasons for this are numerous. In certain instances it is due to a lack of knowledge. Technological innovations are continuing apace and it can be difficult for facilities operators to understand what actually is and is not possible, in terms of metal separation, recovery and recycling. Elsewhere, other organisations understand the capabilities of modern technology, but fear the apparent investment associated with this state-of-the-art plant and equipment. In truth however, more sophisticated kit can in fact handle a greater amount of material, achieve a more advanced metal separation process, and increase the organisation’s yield accordingly.

The key is therefore to raise awareness of the opportunities that exist within the UK metals industry. Already contributing a reported £5.6bn to the economy, metals recycling has been hailed a British success story. But there is even more potential to be realised.

Tackling contamination

One of the biggest obstacles in metals recycling is contamination.

Take used beverage cans (UBCs) for instance. While all recycled cans are valuable, it is the non-ferrous metals such as aluminium, which carry the greater worth. Aluminium and steel cans therefore need to be separated, and any contaminants – including widgets or other waste substances – removed.

Recognising the limitations of MRFs’ sorting systems, which cannot achieve 100 per cent separation, the more forward-thinking waste firms shred loosely baled UBCs to liberate the materials. Overband magnets are then used to extract ferrous metals and an eddy-current separator removes any other ‘contaminants’, leaving just the aluminium. If a pure aluminium is sought, the lacquer would then need to be stripped.

This separation process can be used for the recovery of metals from other areas of industry too. In the automotive world for example, cylinder heads are often made from aluminium but fitted with steel inserts. Shredding and sorting equipment therefore enables the ferrous and non-ferrous metals to be separated, prior to being sold for recycling.

Increasing smelting efficiency

Non-contaminated metals obviously command a greater price per tonne, something any metal recycler strives for. Yet a more sophisticated approach to metal sorting can achieve benefits for smelters too.

Firstly, metals that have been shredded down to a smaller size can be fed into a furnace via a screw pump. This enables a continuous supply of material, which can reduce heat loss during the furnace filling process.   

Secondly, it is said that for every tonne of contamination, twice the amount of aluminium could be lost in the smelting process. If the metals are non-contaminated the smelting efficiency is therefore further improved.

Releasing trapped metals  

Examples of valuable metals being ‘trapped’ within other products and materials do not stop with drinks cans and car parts. Steel can be separated from uPVC windows and tyres for instance, and precious copper can be extracted from cables. The value of this latter metal – once it has been separated from PVC sheathing and steel wire – is undoubtedly one of the reasons that cables are increasingly being shredded in the UK rather than being shipped overseas.

E-waste opportunities

While often considered a separate waste stream – due to the complexities that surround its specialist treatment – it should not be forgotten that WEEE contains many valuable metals too. 

In December 2013, the UN-backed ‘Solving the E-Waste Problem (StEP) Initiative’ claimed that, globally, the annual level of end-of-life electronics will increase by a third by 2017. It is therefore important that the UK’s WEEE recycling capabilities continue to evolve in order to deal with this escalating production of waste.

More specialists are needed within this complex field. The negative environmental and health impacts of primitive WEEE recycling methods are constantly reported on in the media, but there needs to be greater awareness of the more sophisticated technological options that exist for this type of waste handling.

When managed by an Approved Authorised Treatment Facility (AATF), ‘waste’ electronic products are kept separate from other waste streams and – if not suitable for re-use – are carefully pre-treated to ensure the removal of any hazardous substances. Efforts then need to be made to recover incredibly valuable commodities within the WEEE such as gold, copper and palladium, to name just a few. Of course shredders and sorting equipment can help here, but the most sophisticated of operators will thoroughly hand-separate as much of the metal as possible. This minimises the level of valuable and potentially harmful metals being lost in the dust that inevitably arises from WEEE processing, however slow the shredder speed.

Keeping it simple 

There is nothing wrong with wanting to ensure waste handling operations remain as straightforward as possible. Some companies’ goals are simply to ensure the business runs smoothly, while supporting the UK’s recycling targets, and nothing more. But even these seemingly uncomplicated objectives can be tricky enough in some instances and once again carefully selected technologies have an important role to play.

In the manufacturing and machining industries for example, fine shavings of metal swarf can become almost impossible to handle when they tangle together and form a large mass. Here the priority for a waste handling plant is size reduction, so that the metal can be shredded down to produce a more manageable chip. To take this one step further and improve the company’s bottom line, the shredded fraction can then be sent to a specialist wash plant. Once the cutting lubricant has been cleaned off, the result is a non-contaminated metal which can then be smelted down or baled for re-sale. Of course if the metal is a valuable non-ferrous substance such as brass or titanium, the material will attract an even greater price.

A metal landscape of opportunity

This all goes to show that the metal landscape is one of great opportunity in the UK. Pleasingly, the individual illustrations of companies developing innovative metal recycling processes are already becoming more prevalent. However, it is important to raise further awareness so that organisations within the industry understand exactly what is possible. It is simply a case of establishing a budget and investing in the right technologies, configured to suit the project specification, in order to achieve the desired end result.

Chris Oldfield is managing director of waste shredding specialist UNTHA UK. www.untha.co.uk

Category: Blogs
Novelis Every Can Counts

PROJECTS

Circular Economy Roundtable Discussion Part 3

The final part of our discussion, looking at the business opportunities in the circular economy.

Find out more

Circular Economy Roundtable Discussion Part 2

Part 2 of this three-part discussion looks at the practical implications of the circular economy

Find out more

Other Projects

Recoup Conference 2017Recycling UKNovelis Every Can CountsHanicke Robins Sanderson