Intelligent photoelectric identification of coal and gangue − A review

The separation of coal gangue is a critical step in coal preparation, and accurate identification of coal gangue is a prerequisite for successful separation. However, conventional technologies for separating coal gangue are limited to surface separation. Conversely, photoelectric identification technology can be applied underground in mines, making it highly valuable for research. This paper comprehensively reviews photoelectric recognition systems based on visible and invisible media for coal gangue identification. Image segmentation, feature extraction, and classification are discussed in detail, focusing on the characteristics of coal gangue. Different wavelength invisible light recognition technologies are applied, and the principles and research progress of the X-ray identification of coal gangue are discussed from a particle physics perspective. Furthermore, the limitations of the current literature are analysed, and future research directions are proposed.