Function
The bicyclean is a safe, affordable, and efficient alternative for harvesting electronic waste in developing regions. The bicyclean is a modified bicycle, where a processing chamber replaces the rear wheel and an external steel frame supports the rear hub. Processing of the circuit boards occurs within the sealed chamber and the particles are removed in a covered tray. A feed tube presses circuit board pieces into a large grinding wheel and become pulverized. The particles pass a magnet that extracts ferrous metal particles. The particles then flow over a small eddy current rotor, which is positioned underneath the grinding wheel and powered by a 3:1 gear ratio with the bicycle chain. The changing magnetic fields of the eddy current rotor repulse conducting metal, but have no effect on non-metals; the metal particles are projected horizontally while the nonmetals fall vertically, separating particles in the bottom collection tray. The bicyclean requires a single operator.
Inspiration
International trading of secondhand electronics has spurred accumulation of e-waste in developing countries. At informal dumps common in Ghana, scavengers utilize burning and other crude methods to extract resalable metals from the abandoned material. After visiting such sites on the outskirts of Accra, Ghana, for several weeks in January 2012, I developed profound concern for the environmental and economic impact of the harvesting site. More significantly, I was concerned for the wellbeing of the people that I had met at the sight, and felt compelled to utilize my engineering education in developing a solution. I wanted to design a method whereby my Ghanaian friends could maintain their livelihood, and indeed improved their daily efficiency, but would not be jeopardizing their lives to do so. This project addresses the issues inherent in this system through the development of a device that facilitates metal extraction while ensuring safety, profitability, and efficiency.
Development
The bicyclean is a sustainable and small-scale adaptation of industrial practices for electronic waste recycling. Limited by the lack of reliable or affordable electricity in Ghana, pedal power was the most logical basis for my design. Due to the working structure of electronic waste sights in Ghana, I needed a design that only required an individual or small team for operation. For the recycling process itself, I analyzed contemporary industry practices in Europe and adopted the multi-staged process of shredding and separating, via magnets and eddy currents. In constructing the first prototype, I minimized costs and used components which would be available in Ghana, or which could be substituted with local materials. For instance, I limited the number of magnets used to a size and scale that could be harvested from used stereo speakers. The current prototype modifies a bicycle; future prototypes will allow for a bike to temporarily attach by a belt to a recycling process wheel.