Recycling is the process of converting waste materials into new materials and objects. The recyclability of a material depends on its ability to reacquire the properties it had in its original state.
Recycling can also prevent the waste of potentially useful materials and reduce the consumption of fresh raw materials. It thus lowers energy use, air pollution from incineration, and water pollution from landfills.
Video courtesy of American Chemical Society
What is Material Size Reduction?
Material size reduction is the process by which a piece of material is reduced to fragments of smaller sizes. Generally, the process involves three steps: (i) shredding, (ii) granulation, and (iii) grinding. As it goes through all these steps, the material is reduced to smaller and smaller sizes until it reaches the desired dimensions.
Shredding is the first step during which the waste material size is reduced to much smaller pieces suitable to be further reduced in size in granulators.
During granulation, the waste material is reduced to pieces of even smaller sizes, typically 5 to 12 mm (0.2 to 0.5 inches), depending on the application.
Grinding is the last stage in reducing the size of the material. The ground particles can vary in size from under 0.1 to 1 mm (0.004 to 0.04 inch) depending on the downstream processing needs.
Shredders reduce the size of the feedstock through the cutting action of contra-rotating shredding rollers or knife shafts. Shredders are machines characterized by low shaft rotational speed (RPM) but very high torque. Industrial shredders come in many different designs, sizes, and variations. The choice of a suitable shredder depends on the properties and size of the feedstock, the desired shred size, and the desired throughput rate.
Granulators are single-shaft machines operating at a higher rotational speed to reduce the feedstock size further. Hardened and very sharp steel knives installed on the rotating shaft cut the material while the hydraulic ram pushes the feedstock into the cutting chamber.
A shredder-granulator combo unit combines a shredder with a granulator in a single, space-saving, size reduction system of great efficiency and small footprint. These features allow the combo unit to integrate easily into existing factory workshops.
One of our partner’s testing facilities is a great place to start your recycling project. Send us a sample of the waste material you wish to recycle – plastic, wood, or cardboard – and we’ll test it. Better still, come down to the test center to witness the tests yourself.
We can adjust specific machine parameters during the tests to determine the optimum configuration for your particular application.