Keeping the line moving
Recycling plants handle a wide range of materials, from electronics and metals to plastics and cardboard. Each behaves differently on a conveyor. One load might move freely, while another can clump or cause stoppages. Selecting the right conveyor drive system isn’t just a mechanical task — it requires a clear understanding of how different materials behave, and how conveyors support each stage of the process. Here, David Strain, a technical director - systems integrator, explains how to select drive units for belt feeders, transfer belts and picking belts in recycling plants...
Conveyor systems are integral to the efficiency and safety of recycling operations. According to the UK's Health and Safety Executive (HSE). The HSE emphasises that poorly guarded or improperly used equipment can lead to serious or fatal injuries, highlighting the importance of properly functioning conveyors in maintaining both safety and operational continuity.
Understanding conveyor roles in the recycling line
Most recycling plants use three main types of conveyors: belt feeders, transfer belts and picking belts. Each one plays a different role in managing how material flows through the line. Getting the drive specification right means understanding not just belt speed and motor size, but also how specific materials — such as rigid plastics, shredded metals or compostable waste interact with conveyor motion.
Belt feeders, positioned under hoppers, set the flow rate for the rest of the line. Most use inverter-controlled drives for fine speed adjustment, especially where irregular materials like construction waste require low-speed handling. Open front designs suit bulkier loads, while adjustable door types are used for more consistent materials like PET or glass. In both cases, material characteristics, not capacity, should guide drive sizing.
Transfer belts move material between stages. Drive selection is typically simpler here but still depends on whether fixed or variable speed is needed for flow control. Poor speed matching between belts can lead to material buildup and disruption.
Picking belts, used in manual or automated sorting, also rely on speed control. Slower speeds support positive picking, where more material is removed; faster settings suit negative picking, where only specific items are taken out.
Getting the details right
In some plant layouts, conveyors are fitted with dual drives on opposite sides of the drum. This approach can improve stability and lead to a more even discharge, which can be particularly useful when feeding into shredders or balers that require consistent loading.
Drive performance can also be affected by mechanical issues such as friction. Flat-bed conveyors without proper friction-reducing measures, or those fitted with poorly aligned skirt rubbers, can experience high drag. This increases the risk of motor overheating, drive tripping, and in severe cases, permanent equipment damage.
One option designed to help address these challenges is a Drum Drive solution, which houses the motor and gearbox directly inside the conveyor drum. By removing the need for external motor mounts and drive chains, this design helps reduce friction, minimise maintenance and save space — making it particularly useful in high-demand or compact recycling environments.
Variable speed operation can help prevent many common problems by adapting belt motion to the real-time conditions of the line. Whether selecting drives directly with machine builders or through panel suppliers, taking the time to match the right components to the right task leads to more reliable performance and better throughput.
Each section of a recycling plant plays a role in keeping material moving and preventing bottlenecks. And while every belt moves material, not every drive suits every job. With the right setup, conveyors do more than move waste — they support cleaner output, steadier operations and fewer breakdowns across the whole plant