Magnetic Density Separation (MDS) is a novel method for the separation of shredded complex wastes [7, 8]. It uses a magnetically induced density gradient in a ferrofluid, which allows particles with different densities to follow different trajectories. Small variations in feeding direction, spread, and velocity can significantly affect the quality and purity of the separation. The MDS-based machine (MDX) studied in this research was developed by the Technical University of Delft and Myne Circular Metals B.V. After research on magnet configurations [9], fluid stabilization [10], fluid dynamics [11, 12], and the particle sliding phenomenon [8]. This thesis investigates how feeder geometry, vibration parameters, and material properties influence feeding performance and how this affects the separation. A Discrete Element Method (DEM) model was developed to simulate the behaviour of shredded copper cable feed as it is fed to the MDX by a vibratory feeder. The feed was modelled as a mixture of copper, aluminium, PVC, and PP/PE, represented by superquadric particles. Material properties and interaction properties were calibrated using literature and a Bulk Calibration Approach (BCA). A Design of Experiment (DoE), including a Definitive Screening Design (DSD), was used to calibrate sliding friction and restitution coefficients for all interaction parameters against three Key Performance Indicators (KPIs): discharge time, heap height, and angle of repose. The best-performing parameter set used a sliding friction of 0.8 and a restitution of 0.1, uniformly applied across all material types. The DEM simulations were validated against experimental tests, showing good agreement in mass flow but some deviation in feeding profiles. This calibrated DEM model was then used to test 20 feeder design variations across six base concepts, including straight and arced ends, varied feeder angles, the addition of particle-guiding walls, and different feeding bed interaction parameters. Feeding performance was quantified using four output parameters: horizontal and vertical insertion velocity, horizontal spread (modelled as a Gumbel distribution), and mass throughput. These were selected based on their known influence on separation purity in MDX. The results showed that higher vibration frequencies increased both feeding speed and particle spread. Arced feeder ends tended to increase forward particle velocity and spread, especially at larger radii, while the straight-ended design minimised these effects. The addition of a guiding wall helped reduce horizontal spread without sacrificing throughput. Ultimately, the best concept uses a straight end with a guiding wall to achieve low particle speeds and a narrow horizontal spread, with a throughput of 0.5 kg/s.