MechChem Africa July-August 2023

⎪ Power transmission, bearings, bushes and seals ⎪

Bonfiglioli and start-up company, GreenBig, have collaborated to develop a completely tailor-made shredder solution for recycling PET bottles. GreenBig, a circular economy start-up in the north of France, has developed a new economic model capable of recycling PET bottles. Part of its concept is that these machines can be installed in public places, in supermarkets, for example. Once installed, the recycling machine initiates a sustainable circular economic cycle that benefits both users and the planet. Thanks to a patented bottle densification technology carried out directly on site, the system enables 3 500 shredded bottles to be stored in a bin with a volume of less than 1.0 m 3 . This results in fewer emptying cycles, less maintenance, lower costs per square metre, and reduced transportation and logistics costs. It also reduces sorting and pre-shredding requirements for PET producers. The machine is based on the concept of sorting PET by colour, thus increasing the price/t, and then transforming it into flakes using a special shredder. It was the need for a suitable shredder for this unusual ma chine that led to the collaboration between Bonfiglioli and GreenBig. The search for an optimal solution in Components for stand-alone recycling machines While the recycling process can be car ried out through large and complex plants, compact stand-alone machines are also common. These machines are used for small loads, such as a single product returned for recycling. Bonfiglioli designs and produces custom solutions for reverse vending machines that, for example, typically process one process, which typically use drives from Bonfiglioli’s C-Series helical range, which can accommodate a broad range of compac tor requirements. The compact C Series geared motor features a wide output torque range and an extremely wide range of gear ratios, which are achieved through 2-, 3- or 4-stage versions. The C Series can be coupled with Bonfiglioli electric motors, which are known to achieve first-rate reliability, efficiency and robustness. This allows customers to adapt the C Series to match the torque and output speed requirements of any compacting application.

Bonfiglioli offers products such as the parallel shaft F-Series and the helical bevel A-Series drives for a variety of conveying systems. Inset: Bonfiglioli A10 Series coupled with a BMD servomotor.

line with the GreenBig's needs was initially extremely complex. During the concept development phase, Bonfiglioli presented the customer with a first prototype shred der, and this led to numerous tests before the best solution was identified. GreenBig needed to satisfy key specific requirements: the machine had to be powered from the domestic power supply (230/250 V); the shredder had to fit into the smallest pos sible space; and the unit had to be as silent as possible. To design and develop the shredder, Bonfiglioli initiated an intense co-engineer ing programme in synergy with GreenBig. This produced a solution that directly con nects the gearmotor with the shredder and, above all, meets the required dimensions for the drive. For this reason, an orthogonal gearbox was used with a brushless electric servomotor. It was also crucial to minimise the cycle times to achieve the target shredding goal of a bottle every three seconds. To achieve this, it was necessary to switch from being ‘agile’ to being ‘active’ to increase the capac ity of the DC BUS. To meet all these requirements, the Bonfiglioli single recycling machine was used, fitted with a 300M series inline gear box (3 01 L 1 FZ); a W-series right angled recycled plastic bottle/can at a time. But the machine has to have high reliability and a long operating life. These are typically stand-alone shredders that consist of FEF drives that deliver the expected reliability and longevity. “We believe product development relies on passion, efficient processes and the abil ity to understand customers’ needs. After an in-depth analysis, our design teams will first identify these company needs. Then,

gearbox (W 63 UFC1); a Bonfiglioli BMD series servomotor (BMD 102); and an Active Cube inverter (ACU 210) with an EtherCAT ACU communication module. At the end of the project, GreenBig noted: “Our collaboration with Bonfiglioli was a fundamental factor in developing this project. In the end, the solution fully satis fied all our needs, both in terms of time and energy performance, on a technical level and in compliance with the requirements. This has allowed us to integrate the drive perfectly into the system we created.” through dedicated calculation tools, the team is able to simulate recycling machine capability and the associated transmission performance, which allows the total devel opment time to be significantly reduced. “Ultimately, this development approach allows the design proposal to be adapted and optimised to best suit key factors such as performance, installation limitations and maintenance,” Dos Santos concludes. www.bonfiglioli.com/south_africa/en

Bonfiglioli and GreenBig collaborate to recycle PET bottles.

GreenBig’s PET bottle recycling system enables 3 500 shredded bottles to be stored in a bin with a volume of less than 1.0 m 3 .

July-August 2023 • MechChem Africa ¦ 15