NIT Rourkela Patents Low-Cost Recycled Filament Extruder

Why recycled filament still struggles to scale

Most 3D printing filament today is made from virgin plastic. That keeps prices high and sends usable polymer to landfills. Recycled filament exists, but inconsistent diameter, weak mechanical properties, and expensive extrusion equipment have kept it from widespread adoption. A new patent from the National Institute of Technology Rourkela (NIT Rourkela) aims to change that equation.

The system

The patented setup costs approximately ₹45,000 and fits into a compact footprint. It includes an extruder, heating chamber, controlled cooling mechanism, and PID temperature controllers to keep processing conditions stable. A diameter sensor provides real-time feedback, adjusting the puller speed so the output stays compatible with standard desktop printers.

The system also accepts reinforcement materials mixed with recycled plastic, producing composite filaments with better strength and durability than straight recycled stock alone.

What the team tested

Laboratory runs showed the resulting filament met dimensional accuracy targets and held up in mechanical tests. The research team, led by Prof. Sandhyarani Biswas and Prof. Sujit Sen, secured the Indian patent under Application No. 202431068691 on 30 July 2026.

Where it could matter most

The authors see the biggest impact in universities, makerspaces, and small workshops that cannot afford industrial extruders. Instead of buying every spool, those institutions could process local plastic waste into feedstock on demand. That cuts material costs and shortens the supply chain from overseas resin manufacturers.

Prof. Sen described the project as a step toward a closed-loop system where plastic waste is recycled, reused, and remanufactured into value-added products. If the system works at the scales the team predicts, it gives schools and small manufacturers a practical path to circular 3D printing feedstock.