Manufacturers could profit from swarf processing system
UK manufacturers are losing millions in potential profit through inefficient recycling, according to the company behind a new in-house waste management system.
Honda and BAE Systems are two of the first clients to use the swarf (metalworking waste) processing machines, which were officially introduced to the market at MACH 2012 last month.
Nederman UK, the company behind the new recycling system, produced a report into UK manufacturing waste that found that average businesses are losing up to £780 in potential revenue for every tonne of metal waste they recycle.
‘Metal prices have been going up over the last three years and the chances of them coming down are very slim,’ Nederman’s machining business manager, Nick Dulley, told The Engineer. ‘The price of swarf is now three times what it was a few years ago. The tsunami in Japan last year has made the price go up even more because it created a lot of problems in the supply chain.’
Nederman’s new system uses vacuum pumps to automatically collect swarf from the machining process. Oil and coolant are separated from the metal, which is then turned into manageable briquettes that can be reused or sold.
‘A couple of tonnes of high-value metal such as copper, aluminium or brass could provide a very nice revenue stream,’ said Dulley. ‘Large manufacturing companies in particular are now using their size to trade metals on the open market.’
By processing the swarf as soon as it comes off the machines rather than sending it away to another company, companies can maximise their potential revenue, he added.
‘Other equipment is available but other companies don’t use the same processes as we do and don’t provide all the technology themselves.’
Honda UK Manufacturing (HUM) is using the new system to process the 1,000 tonnes of swarf waste produced every year — equivalent to around one to two lorry loads a day — at its engine plant in Swindon.
The company has increased its average revenues from selling the swarf by a factor of three, as well as increasing income from recycling coolant. The cost of the complete system was paid back in less than 24 months.
Removing the swarf automatically from the production line also prevents any slowdown in the system and cuts downtime by keeping the facility clean, as well as reducing energy usage, labour costs and environmental impact, according to Nederman.
The process works by first shredding the swarf, breaking the tangled material into a more uniform chip that is easier to process.
This is passed by conveyor to a centrifuge that removes moisture from the swarf. This stops it from clumping together and removes coolant and oils from the cutting process contained in the moisture that are then passed to a separate processing unit.
The remaining metal is then passed over a multi-stage set of magnetic rollers to remove any ferrous particles from the swarf. Larger ferrous debris is first removed by a natural-earth magnet before a raw-earth magnet is used to extract smaller ferrous particles. In the instance of the Honda plant, which processes swarf with a high aluminium content, the waste is processed again by being passed over a natural-earth magnet that helps reclaim more than 99 per cent of the aluminium with less than 0.25 per cent ferrous material remaining.
Coolant, water and oil are also reclaimed at each stage of the process and reused or recycled where possible.
Once the metal is reclaimed from the production system, it is turned into briquettes in order to reduce its size before being transported to a reprocessor.
Nederman has studied the potential of the system for typical manufacturers of car engines, aerospace parts, steel machine tools, aluminium furniture and brass door hardware. It found that the recycling system’s potential increased profitability would range from £146,000 a year for an average aerospace manufacturer to £1.4m for a machine-tool company.