Supporting Plastic Recycling in Blantyre, Malawi
An ETH4D Research to Action project by former master's student Timo Stutz prototyped a device to clean and prepare plastic bottles for recycling
Design of an HDPE bottle collection and pre-cleaning system for recycling in Blantyre, Malawi
PI: Timo Stutz
Partner: external page WASTE Advisers
While plastic usage in Malawi has expanded alongside population growth and urbanization, structural barriers have largely prevented the implementation of plastic recycling schemes, with the exception of small NGO-based endeavors. Through a Research to Action grant, recent ETH graduate Timo Stutz aimed to enable closed-loop recycling by prototyping a device for pre-cleaning and preparation, two overlooked but essential parts of the recycling process.
The project began with research and planning in Switzerland, whereTimo designed a bottle washing station to prepare collected HDPE bottles for recycling as part of his research with the external page Global Health Engineering Group, lead by ETH4D member Prof. Elizabeth Tilley. The subsequent phases relied on a trip to Blantyre, Malawi, to turn the theoretical design into a tangible solution embedded in the local ecosystem.
In Blantyre, Timo collaborated with local waste management specialists WASTE Advisers, beverage company Chibuku Products, and Arkay Plastics, its bottle manufacturer. The team focused on sourcing local material and know-how for building the bottle pre-cleaning prototype. The device inflates crushed bottles to restore them to their original shape, cleans with brushes and water jets pressurized by a manual pump, and provides infrastructure for stacking the cleaned bottles and preparing them for transport.
Through conversations with partners and their closely-related stakeholders, such as the tavern mamas who sell the bottled drinks, the team was able to iterate the design through a feedback loop. This ensured that the prototype could be tested and refined for its ability to withstand the rigors of daily use, while also being simple enough for users to operate and maintain.
The final design introduces an effective method for preparing HDPE bottles for recycling without any need for electricity or running water. It is adapted for tight tavern spaces, sustainable workflows, and reproducible production through local steel workers and engineering companies. In the next phases of the project, led by PhD student Lin Boyton, the prototype will be incorporated into a recycling pilot program that will test its scalability. The technical documentation and CAD drawings of the current prototype are freely accessible online.