The phrase seven types of plastic recycling usually refers to the seven resin identification codes found on plastic products—not seven separate recycling technologies.
The main types of plastic pelletizers are strand pelletizers, water-ring or die-face pelletizers, underwater pelletizers and air-cooled hot-cut systems.
A plastic extruder uses heat and screw rotation to turn solid plastic material into a controlled, continuous melt. When the extruder is connected to filtration, cooling, cutting and screening equipment, it becomes the central part of a plastic pelletizing machine.
Pelletising and pelletizing mean the same process. “Pelletising” is the British English spelling, while “pelletizing” is the American English spelling. Both terms describe converting a material into pellets.
The top five producers of plastic waste depend on the dataset and measurement method. For total municipal plastic waste in the 2020 data presented by Our World in Data, China and India rank highest, followed by the United States, Brazil, and Indonesia.
Plastic processing machines can be grouped by what they do to the material: prepare it, melt and shape it, form finished products, recycle waste, or support the main production process.
A plastic pelletization machine converts prepared plastic waste into reusable granules. The material is fed into an extruder, conveyed and melted by a rotating screw, filtered and pushed through a die, then cooled and cut into pellets.
A budget plastic pelletizer may be suitable for simple, stable materials and lower output, while a premium plastic pelletizing machine is normally configured for tighter pellet consistency, difficult polymers, longer production hours, and more precise process control.
A single screw extruder uses one rotating screw to convey, melt, pressurize, and extrude plastic. A twin screw extruder uses two interacting screws, providing stronger mixing, more flexible material conveying, and better control when additives, fillers, pigments, or several polymers must be compounded.
PC is generally much stronger than standard acrylic when strength refers to impact resistance. Polycarbonate can absorb substantial impact and deform without breaking, while acrylic is more likely to crack or fracture after a sharp blow.