| With the rapid increase in the output of construction waste,its impact on the environment has become increasingly obvious,and the disposal of construction waste should be based on resource utilization.The wide range of sources and complex composition of construction waste in my country have increased the difficulty of sorting,resulting in a resource utilization rate of only about 5%.As the main component of construction waste,waste concrete can alleviate the shortage of natural sand and gravel by manufacturing recycled aggregate for engineering construction.However,the light material impurities in waste concrete seriously reduce the quality of recycled aggregates and limit its application range.In view of the shortcomings of the existing light material sorting technology,the introduction of bounce sorting technology provides diversified choices for the bounce sorting process of construction waste,provides a reference for the design of bounce sorting equipment,and helps to break through the bottleneck of construction waste sorting technology.Analyze the movement process of a single particle on a moving slope,determine the conditions for the particles to bounce,roll and slide on the slope,establish a mathematical model for the distance of the particle along the slope,and summarize the main factors that affect the movement of the particle along the slope factor.The triaxial size of waste concrete particles and the coefficient of restitution and friction with different material surfaces were measured.Discrete element analysis software EDEM was used to establish discrete element particle models of waste concrete and wood chips.Based on the performance indicators of waste concrete sorting rate,wood chip sorting rate and aggregate impurity rate,single-factor simulation experiments are carried out to explore the movement characteristics of particles on the sorting conveyor belt and the law of influence on sorting performance.Determine the better level range.The orthogonal scheme was designed for simulation,and the influence degree of each factor on the sorting performance and the best parameters were determined through range analysis and comprehensive balance method.Physical experiments are used to verify the influence of the inclination angle of the sorting surface and the speed of the conveyor belt on the sorting performance,and the experimental results are basically consistent with the simulation results in the change trend.The physical experiments are verified by selecting some orthogonal scheme parameter groups,and the experimental results are obtained.Similar to the simulation results,it shows that the method of using EDEM software to simulate the bounce sorting of construction waste is feasible and the data is reliable.The optimal parameter group was tested and verified,and the aggregate sorting rate was 95.11%,the light wood chip sorting rate was 88.01%,and the aggregate impurity rate was 1.77%.The bounce sorting method of double-layer belt conveyor is proposed.Through simulation analysis,it is found that the crosstype arrangement can effectively remove the light impurities in the aggregate,and the impurity rate is 0.14%.According to the research results,a three-dimensional model of the belt conveyor,the core equipment for bounce sorting of construction waste,was designed,and ANSYS Workbench was used to conduct a static analysis of the key component rollers.The results showed that the designed rollers meet the strength of use.According to the research results,the bounce sorting process is proposed.This topic studies the bounce separation mechanism of waste concrete particles and wood chips,provides theoretical basis and data support for the bounce separation method to remove light material impurities in recycled aggregates,and provides a new solution to the problem of construction waste separation.The structure design of the bounce sorting belt conveyor is carried out to lay the foundation for the application of bounce sorting in industrial production. |
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