Abstract The Daqin Railway is China's first electrified double-track heavy-haul railway line dedicated to coal transportation. Over the years of operation, the tunnels have been covered with a thick layer of coal dust, which also pervades in the air. Worse is that the coal dust has even buried the rail joints in some sections, making the repair and maintenance of the line difficult. This paper introduces a coal-dust removal device for railway tunnels that integrates pipeline transportation with dust-collection techniques. The device is mainly composed of a power system, a conveying system, a dust-filtration and collection system, and a control and protection system. The key technical elements of the system, such as the dust-extraction method and dust-filtration and collection parameters, are optimized based on the characteristics of the coal dust in the tunnel (obtained via field trials), which greatly enhances the adaptability of the device. Coal-dust removal efficiency reached over 20 t/h, which improves the working environment, reduces the intensity of manual work required and solves the problem of coal-dust removal from the most polluted area—within 500 m of the tunnel entrance.