Batch measurement and statistical analysis of coal gangue particle morphology based on the three-view method

Coal gangue morphology affects slurry flow and pipeline transport, but existing methods lack efficiency and accuracy. This paper proposes a batch measurement method using three-view orthogonal photography. Projections from three perpendicular directions are captured to extract Feret diameters and calculate 3D dimensions and morphological parameters (aspect ratio, flatness ratio, rectangularity, orthogonal circularity). Thirty particles were randomly selected from each of three size fractions (0–5, 5–10, 10–15 mm), totaling 90. Micro-CT of 15 particles validated accuracy. Repeatability assessment showed intraclass correlation coefficients (ICCs) of 0.90 (aspect ratio) and 0.89 (flatness ratio). CT validation showed an 8.5% average relative error for orthogonal circularity versus CT sphericity. Results: small particles tend to be spherical (mean circularity 0.823); medium particles are most elongated (aspect ratio 1.654); large particles are flattest (flatness ratio 0.384). As particle size increases, flatness ratio and circularity decrease, while aspect ratio peaks at the medium fraction. Aspect ratio and circularity show a significant negative correlation (r = −0.894 to −0.837). Morphological parameters differ significantly across fractions (p < .05), with circularity most sensitive to size (F = 7.018). This method overcomes the efficiency-accuracy trade-off, providing a reliable tool for batch morphological characterization. Statistical distributions can support DEM simulations and backfill optimization.