In-House Recycling With Vecoplan Shredders

In-house recycling has become well established with plastics processors. They
recycle their waste and feed it back into production. This enables them to use
uncontaminated raw materials and reduce manufacturing costs. Vecoplan supplies
efficient machines which shred and pulverise large-volume input material. These
process steps are combined with the conveyor equipment. With a modern and
intelligent machine design, this turns a shredder into an integrated production
component. Reject material can be fed back “in-line”.

Companies are more and more frequently processing their reject material to form regrind material and feeding this back into production. This so-called in-house recycling has become an established practice, as in doing so processors make significant cost savings. “On the one hand, they have to pay less for expensive new material and, on the other, there is no need for disposal in external recycling plants,” explains Klotz. Furthermore, the space in the workshop where reject material is stored can be considerably reduced.

Absolutely clean material feedback

One of the world’s leading manufacturers of high-quality Intermediate Bulk Containers (IBCs), tanks and drums commissioned Vecoplan AG to design, engineer and implement a machine which was capable of economically shredding large-volume input material to a grain size of 40 x 40 mm. It had to enable the pre-consumer material to be recycled absolutely cleanly and without contamination directly from production.

The company produces the IBCs in white, black or blue. The production waste delivered therefore had to be treated with 100% colour separation. If contamination should occur, this would result in further rejects, which, however, it would no longer be possible to reprocess. “The system must therefore be absolutely clean before changing the colour. It is therefore crucial that operators are able to clean the system easily,” explains Klotz.

Furthermore, the material for granulation must be homogeneous when it passes into the grinder. Another factor was that space in the workshop was at a premium. It was therefore necessary to make the machines needed for recycling as compact as possible. “We also had to ensure that the material flow between shredding and granulation was coordinated,” explains Klotz.

Requirements fulfilled

As the heart of the system, Vecoplan supplied a shredder from the V-ECO 1300 range. This machine is maintenance, repair and user-friendly. The hydraulic upwards-pivoting bottom flap and the downwards-pivoting screen enable the operator to gain easy access to the rotor. He is able to immediately remove extraneous material, easily rotate or change counter-knives, and reconfigure the machine.

The material is fed in continuously thanks to the angled design of the machine base and the steplessly adjustable slide controller. This ensures that the process is uninterrupted. The material is fed in and shredded via a lifting/tilting device. It then passes into a grinder via a feed channel for granulation. It is finally discharged by means of a closed belt conveyor.

“Throughout the project, we matched the performance of the interfaces exactly to the requirements,” explains Klotz. In order to simplify handling, the shredder’s system controllers are linked to the granulation. The current consumption of the grinder motor determines the load taken by the shredder. In this way, Vecoplan was able to optimally match the material flow between the two systems.

From shredder to production component

“The recycling process could be further improved if the treated raw material were to flow directly into production,” says Klotz. That is to say, the shredding equipment is no longer an insular solution but is integrated into production – a closed loop. The Vecoplan engineers’ objective was therefore to convert a pure shredder into an integrated production component. The decisive factor here is the Overall Equipment Effectiveness (OEE). This is a measure of the added value of the system. It enables both the productivity and the losses to be portrayed. The OEE can be calculated from the factors of availability, performance and quality.

Two in one – shredder and granulator as one unit

In order to recondition the reject material, it is shredded, melted, granulated, cooled and transported – a number of operations which need different machines, require space, have to be matched to one another, and consume considerable energy. “We therefore combine several processes in one unit,” explains Klotz. “For example, in order to achieve a high OEE, we have developed a new shredder- granulator combination with the VD 1100 and a horizontal chipper with the VTH 45/12/3.” The VD 1100 is a result of a collaboration with Aachen-based grinder specialist Heinrich Dreher GmbH & Co. KG.

The machine combines the know-how of two system and machine builders in one housing. It shreds input material, for example purgings, lumps, cork and bulky objects such as IBC canisters and drums, to the desired output grain size in two stages. The regrind material can then be fed back into the production flow. “With our systems, we can achieve a high OEE using this process,” says Klotz.

Vecoplan has fitted the cost-effective ESC drive (Electronic Slip Control) for high energy efficiency. Together with the proven startup and reversing controller from the HiTorc drive, 2 to 2.5 times torque can be achieved for a short time with this combination. “In this way, the user achieves a higher throughput performance and saves energy thanks to the frequency converter,” says Klotz.