In order to make the coal slime drying system operation more stable, through the chain wheel transmission, worm drive, gear drive three transmission contrast, the gear drive was settled. The results showed that the selected gear transmission device solved a series of symptoms in the existing dryers running, and ensured the continuous and stable operation of the dryer, optimized the RD multilayer multistage multi-effect drying transmission device, reduced the cost of equipment maintenance, with the feasibility of the implementation.