Each year, around five million aluminium casting components, such as engine components or structural parts for vehicle bodies, are produced at the light alloy foundry at BMW Group’s plant in Landshut, Germany. All scrap products such as punching waste and sprue systems are recycled and then remelted.
Scrap generated in the past was collected in containers without being shredded, then removed from the basement and returned to the melting process. The cast aluminium parts had dimensions of up to 2m x 1.4m and took up a lot of space in containers, meaning they had to be emptied frequently which required a great deal of time and manpower.
During a programme of reconstruction in the foundry hall, when the casting cells were replaced, the decision was taken to optimise the recycling process and make it more efficient.
Erdwich Zerkleinerungs-Systeme (EZS), based in Igling, Germany, was awarded the contract to design a plant that enabled the collection and shredding of aluminium waste directly from the press.
For this task, it adapted the RM 1350 pre-shredder. On-site shredding means that the containers with scrap parts and punching waste have to be transported far less frequently to a large container, increasing operating efficiency.
The machine is characterised by fast and easy maintenance, long service life, optimum shredding and high throughput. To date, seven systems with soundproof enclosures have been installed for the eight casting cells and punch presses in the foundry.
Loading takes place in freefall, meaning the moulds, which are to be returned to the melting process, now fall from the pressing plant directly into the hopper of the pre-shredder and then into a container measuring 1.4m x 1.4m x 0.9m.
When the container is full, it is transported outside, emptied into a large container, and this is brought to the smelter. The shredding process has reduced the volume of cast parts by 50-60% so containers have to be emptied far less frequently.
The pre-shredders were adapted to the on-site conditions. The drives of the machines, for example, had to be mounted on one side instead of the usual two because of the location of the columns in the building.
In addition, working with the technical department at BMW Group, the standard safety system of the machine was extended: the filling level of the removal box located in the basement and the monitoring of the shredder are now displayed transparently so that a quick response can be made if necessary.
A conveyor belt system could be installed to further optimise the process once all casting cells have been replaced. This would allow rejects to be transported directly into the large container via a conveyor belt.
Richard Adelwarth is project manager at EZS
Fibre RFID labels designed for recycling
Finnish bio-materials manufacturer Stora Enso’s intelligent packaging division has introduced sustainable radio frequency identification (RFID) labels that can be recycled with the fibre stream when they reach end-of-life.
Conventional RFID labels are plastics-based, but Stora Enso’s Eco range uses a fibre-based substrate and low-cost conductor that offers high conductivity.
The paper-based tags have no environmental impact on the paper and cardboard recycling chains, nor any significant impact on landfill operations or their emissions.
They are manufactured using ‘clean and green’ manufacturing processes and do not contain plastics or toxic materials. They have also passed industry-standard tests for temperature and humidity, temperature cycling and tag bending.
The use of a paper substrate enables a thinner tag structure, as well as the elimination of one plastic substrate layer and two adhesive layers when compared with conventional tags. The thinner structure makes the label more flexible and it adheres well to curved surfaces. It can be embedded into packaging or converted into stickers.
Designed for the retail, industrial and pharmaceutical markets, the label combines anti-tamper functionality and wide-band performance in on-metal and other hard-to-tag applications.