Optimization and experiment of key components in pneumatic peanut pod conveyor

Research interest in pneumatic conveying technologies in processes such as peanut harvesting and shelling has grown rapidly in recent years. However, the use of pneumatic conveyors in this application suffers from high pod damage rates and duct obstruction. To address these issues, we analyzed the critical speed of pneumatic transport for conveying the peanut pods and measured the angle of friction and coefficient of restitution of peanut pods on a variety of material surfaces. Based on the results of these tests, optimizations and improvements were made to the separator bowl, air supply duct, and conveying duct. A pneumatic conveying experiment was then performed using peanut pods. In the factorial experiment, it was found that increases in fan speed increase the pod damage rate and transport efficiency, while increases in the thickness of the cushioning/anti-obstruction layer decrease the rate of pod damage and transport efficiency. Pod damage rates were significantly affected by fan speed, the thickness of the cushioning/obstruction prevention layer, and interaction between these factors, while transport efficiency was only significantly affected by fan speed. It is proved by the machine verification test, the optimal parameters for the pneumatic transport of Baisha peanut pods with a moisture content of 7.24% was a fan speed of 2700 r/min and a cushioning/anti-obstruction layer thickness of 6 mm. A pod damage rate of 5.19% and transport efficiency of 92.03% were achieved using these parameters, which are sufficient for meeting the requirements of industrial applications.