HighlightsBased on a proposed method combining airflow with a cylinder sieve, a separation device was designed for aggregates of plastic film residue and impurities.The influencing factors were determined by analyzing the separation mechanism and verified by experiments.A response model was successfully built, and a significance test was performed.This study potentially provides a basis for designing separation equipment for film-impurity aggregates.Abstract. Separation of plastic film residue from impurities has challenges, including a high impurity rate and complex operation, causing reuse problems after the recovery of plastic film. To solve these problems, a new method is proposed combining airflow with a cylinder sieve to design a separation device for film-impurity aggregates. In this study, the changes in the movement of film-impurity aggregates during the separation process were initially analyzed for the separation device. The suspension speed of different materials, the rotation speed of the cylinder sieve, the airflow speed of the inlet pipe, and the inclination angle of the airflow were selected as experimental factors, while the impurity rate in the film and the film content in the impurity were used as evaluation indicators. A Box-Behnken test design was used to design a three-factor and three-level test to analyze the influence of each factor on the separation performance. The results indicated that the factors affecting the impurity rate in the film, in descending order, were the airflow speed of the inlet pipe, the angle of the airflow, and the rotation speed of the cylinder sieve. On the other hand, the factors affecting the film content in the impurity, in descending order, were the airflow speed of the inlet pipe, the rotation speed of the cylinder sieve, and the angle of the airflow. Design-Expert software was used to analyze the effect of each factor on the evaluation indicators, and optimal working parameters were obtained. This study shows that the optimal rotation speed of the cylinder sieve, airflow speed of the inlet pipe, and inclination angle of the airflow were 22 rpm, 7 m s-1, and 4°, respectively. An experiment was performed to verify the optimal values. The impurity rate in the film and the film content in the impurity for the optimal design were 11.87% and 0.121%, respectively. The results indicate that the optimization scheme of the device is feasible. Keywords: Film-impurity agglomerates, Model, Pneumatic cylinder sieve, Separation mechanism.