Electrostatic adsorption-based removal of foreign fibers from raw cotton: A mechanistic and performance study

This paper proposes a method for separating foreign fibers from raw cotton based on the synergistic effect of dielectric polarization and electrostatic adsorption. A separation device was designed, and its mechanism was analyzed through simulation. Firstly, a two-dimensional physical model of the cotton impurity fiber separation device was established, and the numerical solutions for key parameters such as the distance between the electrostatic roller and the conveyor belt, voltage, conveyor belt linear speed, and the equivalent particle diameter of the heterogeneous fibers were obtained using the finite element simulation software. Second, combined with the material properties of foreign fibers and raw cotton fibers, the differences in adsorption effects caused by different forces acting on the foreign fibers in the separation device were analyzed. The simulation results show that when the voltage is 30 kV, the distance between the electrostatic roller and the conveyor belt is 100 mm, and the conveyor belt's linear speed is 0.11 m/s, the average adsorption efficiency reaches 68%. Compared with traditional separation methods, this study demonstrates superior separation efficiency and adaptability under mixed foreign fiber systems. The adsorption efficiency not only validates the feasibility of the "polarization-adsorption" collaborative technology method, but also future research is expected to explore the coupling mechanism of flow field, temperature and humidity, in order to better understand the behavior of fiber migration under complex working conditions. • Spatial non-uniform electrostatic field enhances foreign fiber separation by increasing force differential with cotton. • Integrated airflow-electrostatic separator balances efficiency, low energy use, and easy integration. • Electrostatic-airflow coupling model optimizes separation efficiency and energy use for system design.