Research And Design Of Straw Conveying And Drying System

The conveying and drying of straw is an essential part of the project of straw direct combustion power generation, while the conventional conveying and drying equipments used in straw-fired power generation project have some shortcomings, such as low efficiency, large area, complex structure bulky ancillary equipments and so on. In this paper, the straw conveying and drying equipments at home and abroad are compared and analyzed at present, and a new straw conveying and drying equipment with small footprint, simple structure, good drying effect will be proposed.Firstly, the current situation and trend of straw direct combustion power generation at home and abroad are studied in this paper, and the characteristics of conventional straw conveying and drying equipments are analyzed emphatically. Then, a new straw conveying and drying equipment is proposed that collects the function of conveying and drying, and its major components are designed. At the same time, a control system used in straw conveying and drying process is determined in this paper. The main contents:1) A new straw conveying and drying equipment is proposed that collects the function of conveying and drying, and its working principle, structural features and advantages are elaborated; Based on the main control system types used in straw direct combustion power plants, the appropriate DCS control system is selected, and the control requirements of conveying and drying process can be met.2) After the requirements of the equipment, characteristics of the structure and characteristics of straw are analyzed, the wind turbines used for straw drying process are determined; After the movement characteristic and constrains within the track of the scraper are analyzed, and combining with the productivity and overall size of the equipment, the structure and the parameters of the scraper, the material passage, and the frame are worked out, and the mechanical transmission parts are also designed.3) According to the approximate size of the control system, the system's hardware configuration is completed. Then, after the structural characteristics of the equipment, the location distribution of detection point, and the physical quantity monitored of the control system are analyzed, the appropriate sensors are selected and field I/O's configuration are completed. Finally, the interface circuits from the sensors to field I/O about output signals and from the master to the field devices about control signals are designed.