Enhanced Recovery of Magnetic Materials from Fly Ash Using Spiral Dry Magnetic Separation Technique

Fly ash, a substantial byproduct of coal combustion in thermal power plants, poses significant disposal challenges due to its vast generation and limited utilization. The presence of Fe3O4 imparts weak magnetic properties to fly ash, making magnetic separation an attractive approach for its recovery. However, traditional magnetic separation methods often struggle with low efficiency, inadequate segregation between magnetic and non-magnetic components, and the presence of non-magnetic impurities in the final product. This not only limits resource recovery but also hinders efforts towards sustainable waste management. To address these limitations, this study aimed to enhance the recovery of magnetic iron oxides from fly ash using spiral dry magnetic separation. The magnetic circuit of spiral dry magnetic separator was simulated with Ansys Maxwell, and experiments were conducted to optimize separation parameters, such as rotational speed and separation cycles. The optimal conditions identified are 60 rpm, where iron oxide content peaks at 42.7%, and four separation cycles, ensuring maximum recovery. The synthesized magnetic product exhibits high saturation magnetization, indicating its potential for diverse applications. The spiral dry magnetic separation technique offers a practical solution for waste management and fly ash valorization, addressing environmental concerns and promoting resource recovery.