Optimisation of soil-agent particle distribution in a new chain plate soil remediation device based on discrete element method

To improve the working efficiency of in-situ soil remediation equipment, this paper designs a new type of chain plate soil remediation equipment based on the working principle and technical requirements. The mixing process of soil and chemicals under different parameters was investigated using the discrete element method and the orthogonal test method. The experimental designs were all based on horizontal movement speed, chain knife speed, screw speed, and homogeneous mixing pitch as test factors and discrete coefficient and soil fragmentation rate as indices. The test method uses a unidirectional test to determine the value of the reference centre level for the orthogonal test and a combined balancing method to determine and validate the optimum parameters of the soil remediation device. The optimised parameters were determined as follows: the horizontal movement speed of the mechanism is 0.15 m/s, the rotational speed of the chain knife is 5.25 m/s, the rotational speed of the screw is 187.5 rpm, and the homogeneous mixing pitch is 98 mm, respectively. The dispersion coefficient was reduced by 7.43% and the soil fragmentation rate increased by 5.45% compared to the operating parameters of the baseline group.