Research and prospect of underground intelligent coal gangue sorting technology: A review

• Reviews existing coal gangue sorting research. • Thoroughly outlines key technologies of underground intelligent coal gangue sorting. • Innovatively proposes intermittent and continuous coal gangue sorting devices and methods for underground usage. • Identifies the bottlenecks in the development of underground intelligent coal gangue sorting technology. As a by-product of coal production, coal gangue, if not handled properly, will pose an important hidden danger to the environment and safety. Using underground intelligent coal gangue sorting technology can increase efficiency, protect the environment, and enhance safety, which is essential for achieving efficient and eco-friendly coal production. This article reviews the current state of research on coal gangue sorting methods on the surface and underground, comparing their advantages and disadvantages, and analyzes their applicability. It also systematically summarizes the key technologies involved in underground intelligent coal gangue sorting. The article innovatively proposes the concepts of intermittent and continuous sorting and develops related devices and methods. Finally, it identifies the bottlenecks in the development of current underground intelligent coal gangue sorting technology and suggests future directions in response to current challenges.