Ball mills are a commonly used type of lignite grinding machine. They consist of a cylindrical shell that rotates horizontally and is partially filled with grinding media, usually steel balls. As the shell rotates, the balls are lifted and then cascade down, striking the lignite and grinding it into smaller particles. Ball mills can handle a wide range of lignite qualities and are suitable for both small - scale and large - scale operations. However, they may require relatively more energy compared to some other types of grinding machines.
Raymond mills are another popular choice for lignite grinding. In a Raymond mill, lignite is fed into the mill and ground between a rotating grinding roller and a grinding ring. The roller presses the lignite against the ring, generating a grinding force that crushes and grinds the material. Raymond mills are known for their relatively high efficiency in producing fine - to - medium - sized lignite powders and are often used in industries where a consistent powder quality is required.
Vertical roller mills have also gained significant popularity in lignite grinding applications in recent years. In a vertical roller mill, lignite is ground between rotating rollers and a stationary grinding table. The material is fed onto the table, and the rollers apply pressure to grind it. Vertical roller mills offer several advantages, including high energy efficiency, the ability to dry the lignite during the grinding process (which is beneficial due to its high moisture content), and the production of a fine and uniform powder.
