A New Blade Design for Municipal Solid Waste Bag Opener Machines: A Static and Fatigue Finite Element Analysis Study

Abstract

Municipal solid waste (MSW) presents a global challenge, carrying health and environmental risks without proper recycling and disposal methods. Mechanical-biological treatment (MBT) emerges as a promising solution capable of recycling MSW and reducing landfill volumes. However, the efficiency of MBT heavily relies on the bag opener machine, which extracts waste from bags. Therefore, enhancing the bag opener machine's performance is crucial for optimizing the MBT process. This paper introduces four blade models (A, B, C, and D) with different cutting angles (60°, 50°, 45°, and 30°, respectively) aimed at achieving high efficiency, low power consumption, minimal maintenance costs, and extended service life. The blade design was developed using the 3-D modeling software, SOLIDWORKS. Additionally, the paper presents primary calculations of the bag opener machine, which were informed by a review of MSW characterization studies. Static and fatigue finite element analyses (FEAs) were conducted under a pressure of 1 MPa to assess blade strength, performance, and durability. The results indicate that the proposed design can handle a capacity of approximately 30 tons/hr with a power consumption of 22 kW. Notably, blade model D, featuring the minimum cutting angle of 30°, exhibits the lowest Von Mises maximum stress at 15.18 MPa and the minimum factor-of-safety (FOS) at 18.12. Fatigue stress analysis reveals a life expectancy of 10⁶ cycles for all blade models. In conclusion, model D demonstrates superior strength, FOS, and durability, making it the optimal choice for the bag opener machine.