One of the most important steps in the recycling process is size reduction. Size reduction is the process of breaking down large materials into smaller pieces. This makes it easier to transport, sort, and process the materials.
There are a number of different size reduction technologies that can be used in recycling operations. Some of the most common technologies include:
In order to use materials directly in processes like injection moulding, extrusion, blow moulding, and thermoforming, granulators reprocess materials into a size and density similar to virgin resin. Although most granulate falls between 6 to 12 mm, they can often produce particles as small as 4 to 18 mm . They are able to reprocess shredded materials, and small to medium-sized pieces, and process scrap. Granulators are often placed next to the injection or blow moulding, but there are also “under the press” units and central systems, which are largely utilized in thermoforming and recycling applications.
Shredders are used to reduce bulky components into “chunks” that measure between 50-100mm. In comparison to physically cutting up pieces, this can be a more affordable option. Given their versatility and effectiveness with a variety of materials, shredders are often used in commercial recycling. Processors are using them more frequently to reduce huge pieces to a size that can be fed into a granulator. The majority of shredders are single-shaft machines, although there are also 2- and 4-shaft options. Some variants, like the one depicted below, combine a shredder and a granulator into a single machine.
The Benefits of Size Reduction in Recycling Operations
There are a number of benefits to using size reduction in recycling operations. These benefits include:
- Improved efficiency: Size reduction can improve the efficiency of the recycling process by making it easier to transport, sort, and process the materials.
- Reduced costs: Size reduction can help to reduce the costs of recycling by reducing the amount of energy and labour required.
- Increased safety: Size reduction can help to increase the safety of the recycling process by reducing the risk of injury from large pieces of material.