Research Progress in Sustainable Mechanized Processing Technologies for Waste Agricultural Plastic Film in China

The mechanized processing of waste agricultural film is a crucial technical pathway for addressing agricultural-film pollution. Achieving resource recovery through mechanized waste-film processing—and thereby promoting the sustainable management of agricultural-film pollution—remains a major challenge for green agricultural development. This study systematically reviews the progress and limitations of shredding and film–impurity separation technologies deployed in China’s mechanized waste-film treatment. Based on multi-database searches and citation tracking of the literature published between 2000 and 2025, it comparatively evaluates key unit operations, including cutterhead/blade kinematics, specific energy-consumption (SEC) control, and airflow (air-classification) separation, complemented by engineering analyses of representative machinery. The findings indicate that integrated mechanized recovery lines have become the mainstream approach, although the recovered fraction still contains a high impurity load. Drum-type and shear-type shredding exhibit trade-offs between energy efficiency and mitigation of film wrapping/entanglement. Airflow separation and drum-screen or vibrating-screen modules show reduced separation efficiency and process stability at high moisture contents or when impurities have particle sizes comparable to the film; system complexity and maintenance burdens also warrant consideration. To address these issues, a process framework is proposed that integrates drum pre-crushing, shear fine shredding, air classification, and multi-stage screening, together with variable-frequency drive (VFD) speed control, torque monitoring, and modular design, providing a sustainable pathway for the clean separation and resource recovery of agricultural plastic film waste.