Abstract: Froth flotation is a process for separation of different mineral particles by taking advantage of their difference in surface property, and is an important means for separation of fine slime. The paper presents an introduction to the present status of the research work on the low-rank coal flotation process, low-rank coal surface property modification, flotation agents, the way to eliminate the fine slime entrainment and covering problems encountered at the preprocessing stage ahead of flotation process, the ultrasonic pulp preconditioning method, and the main-stream coal slime flotation equipment currently available. Finally, the author looks ahead to the trend of development of relevant technologies and equipment.