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In order to study the internal deformation and re-crushing characteristics of crushed coal during axial loading, a three-dimensional acoustic emission positioning method specially suitable for crushed coal and rock media was proposed. The compaction acoustic emission characteristics of crushed anthracite were revealed by taking 2.5~5 mm single particle size as sample. The results show that: 1) The compaction process of crushed anthracite can be divided into three stages: initial compression, linear compaction, and plastic compaction. Acoustic emission counts and energy during loading are highly related to three deformation stages; 2) The crushed anthracite has layered compaction and re-crushing characteristics: the particle re-crushing occurs in the middle layer at first. With the increase of compression degree, the re-crushing phenomenon gradually transfers to the upper and lower layers, and finally the particles in upper and middle layers are more damaged; 3) When the strain rate reaches 0.24, the re-screening results show that the reduction of porous structure is the largest in the upper and middle layers after the final compression, while it is the smallest in the lower layer owing to the smallest degree of deformation and compaction.