Plastic film mulching is one of the key technologies for improving agricultural productivity in arid and semi-arid regions. However, residual plastic film can severely disrupt the structure of the topsoil in farmland, leading to a decrease in crop yield. The Hexi Corridor, as the largest seed maize production base in the arid regions of Northwest China, is facing an increasingly prominent issue of residual plastic film recovery. This study designed experiments based on the typical maize planting model in the Hexi Corridor. A discrete element simulation model of the residual film–soil–root stubble complex was established using the Bonding-V2 model and API rapid filling technology. The reliability of the simulation model was verified through shear and puncture tests. The study revealed that the soil type in the Hexi Corridor is heavy sandy soil. The differences between the average maximum shear forces in the simulated and actual shear tests for root stubble–soil complexes at depths of 30 mm, 50 mm, and 100 mm were 4.8%, 6.4%, and 6.5%, respectively. Additionally, the differences in the average maximum vertical loading forces in the simulated and actual puncture tests for root stubble–soil complexes at depths of 50 mm and 100 mm were 6.4% and 12.37%, respectively. The small discrepancies between the simulated and actual values, along with the consistency of particle movement trends with real-world conditions, confirmed the reliability and accuracy of the simulation model. This indicates that the established discrete element flexible model can effectively represent actual field conditions, providing discrete element model parameters and theoretical support for optimizing the design of key components in China’s mechanized root stubble handling and residual film recovery machinery.

To address the negative impacts in recovering large areas of residual plastic film from corn stubble in the Hexi irrigation area—such as the residual film containing substantial amounts of soil, corn stubble, and corn straw, and high power consumption during the operation process—in this study, a combined operation machine was designed for corn straw crushing and residual film recovery. The machine consisted of a double-wing, single-blade shovel for lifting the film and cutting corn stubble, a corn straw-crushing and returning device for reducing the residual film impurity rate, an eccentric teeth shifting cylinder for picking up residual film, a device for shifting residual film, and a collection device for bundling residual film. The key components of the combined operation machine were designed based on an agronomic model for corn planting and the mechanized operation requirements in the Hexi irrigation area. The optimal combination of operating parameters was devised based on theoretical calculations and single- and multifactor simulation tests. The results showed that when the angle of entry of the film-lifting shovel was 25.14°, the rotational speed of the eccentric teeth shifting cylinder was 80.96 rpm, and the forward velocity of the machine was 4.03 km/h, while the rate of recovery of residual film was 92.56%. The field test showed that the residual film contained 16.65% impurities, and the qualified rate of corn straw crushing was 88.51%, with a relative error of 0.65% from the optimized value. The experimental results provide theoretical support and a design reference for research on the mechanized recycling of residual film in large areas of corn stubble.

To solve the problems of high tillage resistance and the rapid wear of the rotary blade during tillage, this study employed a coupled algorithm of the discrete element method (DEM) and multi-body dynamics (MBD) with Hertz–Mindlin with JKR particle contact theory to establish a rotary blade–sandy soil model. The interaction between the rotary blade and sandy soil was analyzed. The results indicated that the lateral and horizontal resistances of the rotary blade reached the peak values near the maximum tilling depth, whereas the vertical resistance reached its peak earlier. Blade wear predominantly occurred on the side cutting edge, bending zone edge, and sidelong edge, with the most significant wear observed on the sidelong edge, followed by the bending zone edge and side cutting edge, which showed similar wear patterns. To reduce wear and tillage resistance, Box–Behnken optimization was applied to optimize the blade’s local parameters. The optimal parameters—the height of the tangent edge end face was 51 mm, the bending radius was 28 mm, and the bending angle was 116°—reduced wear by 22.4% and tillage resistance by 12%. A soil disturbance analysis demonstrated that the optimized blade performs better in terms of tillage width compared to the unoptimized blade. The optimized rotary blade achieves the effects of reduced resistance and wear, improves the lifespan of the blade, reducing material loss, and meeting the requirements of sustainable agricultural production.