Moist fine coal particles are easy to agglomerate and block screen apertures in the screening process,which challenges traditional vibration screen. As liquid bridge forces between particles are the main reason for the agglomerate formations, the agglomerate depolymerization will occur when the large depolymerization energy and impact force are obtained from the collision depolymerization process. By adopting the flip-flow screen, equipped with flexible screen panels, ejection accelerations can reach 30-50g. Thus, depolymerization of the agglomerate can be achieved much easier. But the quantitative relationship between the agglomerate collision depolymerization process and driving parameters of the flip-flow screen are not clear yet. In order to improve the screening efficiency of agglomerates, the agglomerate collision depolymerization process with a single-side driven flip-flow screen is explored in this paper. First, the theorical model solving the depolymerization energy and the maximum impact force are proposed. Then, with the FFlex body of the flexible flip-flow screen panel and the discreate element model of the agglomerate contained the custom contact model of Hertz-Mindlin with Liquid Bridge, the co-simulation of the agglomerate collision depolymerization process is carried out based on the DEM-MFBD coupling strategy and the reliability is verified by an experiment. Results show that, compared to the static screen panel, the agglomerate is easier to obtain high collision depolymerization degree with the flip-flow screen panel. In the collision depolymerization process, the depolymerization energy is proportional to the square of impact velocity of the agglomerate va and the vibration velocity of the flip-flow screen panel y’ while the maximum impact force is proportional to the cube of the cube of va and the square of y’. Particularly, higher depolymerization degree of the agglomerate can be achieved by higher rotation frequency of the crank-guide mechanism and eccentricity of the crank. The research work provides a reference for high efficiency screening of agglomerates.
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