The Study Of Disc Dryer Theory And Dewatering Dynamics

The technical measures for deep reducing coal moisture were urgent needed due to China devoting major effort to implement the new and high technologies used for coal liquefaction and preparation high purity coal. Through the analyses of current situation of technical level for coal drying and dewatering, the paper suggests to take overheat steam produced from power plant as a heat source, use the disk dryer to deeply reduce coal moisture with simple working process and low production cost.Compared with traditional coal drying system, the disk dryer is a indirect drying dryer, in which, the material dried not direct contact with drying medium, so the pollution is avoid, and has the features of simple in process, easy operation, work smoothly and complete the drying in one unit. The formulas for calculating the drying time and the shaft power were established respectively base the analysis of the kinematics and dynamics of the dryer. The formulas for calculating transmit drying rate and emitting drying rate were also established based on the theory of heat transmit and heat emitting. The prototype was designed and manufactured for testing. During the test, under the certain condition, the prototype can reduces the coal moisture from 20% to 0. 5%, the evaporate rate up to 22kg/(m2.h), laying a solid and reliable foundation for its industrialization.