the multi-layer conveyor belt in the belt dryer compartment is arranged at one end of the belt dryer compartment; the conveyor belt is inclined and the top of the conveyor belt extends to the front end of the top conveyor belt to deliver the material to the top conveyor belt; the conveyor belts under the top conveyor belt are alternately distributed before and after the belt drying. the rear end of the dry compartment is arranged at the outlet. dry air produced by heat exchanger (or hot air from hot blast stove) is blown upward by fan through the bottom of belt drying compartment and contacted with countercurrent material to carry out mass transfer and heat transfer, so as to achieve the purpose of removing moisture. in order to facilitate discharging, the discharging inlet is provided with a reflecting inclined plate for squeezing the material on the bottom conveyor belt into the discharging outlet. heat source can be used with steam and hot blast stove. there are many kinds of structures to choose: circulation structure, disposable heat utilization structure, non-standard design according to material requirements, pipeline operation, labor saving and accumulated rich experience. according to the material drying requirements, design layers, design new type, there are many forms of structure can be selected, can meet the requirements of large capacity and production, can configure the energy-saving use of biomass energy, the equipment design company has accumulated rich experience, synchronous transmission, reasonable structure.