| With the rise and application of biomass energy,the technology of biomass solidification has been promoted and developed.The ring mode biomass particle molding machine is one of the most important machines in the field of biomass solidification technology,while the ring mold is the key component of the dense forming of the ring mode granulator,which determines the performance,efficiency and quality of the products.But at present,there are still many problems in the ring model particle forming machine,such as high energy consumption,low output,serious wear of ring mold and poor quality of forming particles.In order to improve the granulation performance of the loop mode biomass granulator,this paper analyzes the forming mechanism and component force of the ring mode biomass granulator,and designs a bionic ring model according to the characteristics of bee nest pressure resistance.The feasibility and quality of the loop model biomass granulator are verified by simulation analysis and actual granulation test.(1)The mechanism of ring mode biomass molding was analyzed,and the material in extrusion area and the key parts of extrusion molding were analyzed.It is concluded that the intake angle condition of material densification molding is needed,and the material of ring mold and roller should be considered in the design of ring mode biomass granulator,so as to improve the material intake and productivity.At the same time,the parameters of the key components,such as the number of rollers,the gap between the ring mold and the roller,the diameter ratio of the ring mold and the roller,are analyzed and calculated.(2)In order to improve the accuracy of the parameters needed in the discrete element simulation of the densification process of corn straw powder in the follow-up experimental study,taking corn straw powder as the research object,the Hertz Mindlin with JKR bond contact model in edem software was used to carry out the parameter calibration of the discrete element simulation model of the densification process of corn straw powder.Through Plackett-Burman test and Box-Behnken test,the parameters are obtained,and the accuracy of the selected parameters is verified.(3)Inspired by the close arrangement of honeybee nests and strong resistance to external forces,a bionic ring mold with honeycomb structure was designed to solve the problems of uneven quality of molding particles and high wear and loss rate of ring mold of molding machine.At the same time,the parameters and dimensions of the ring mold were analyzed and designed.The three-dimensional model of the designed ring mold structure was established by CATIA software,and the discrete element simulation of the densification molding process of the biomass pellet machine using the ring mold was carried out by edem software.Through the post-processing analysis,it was concluded that the honeycomb bionic ring mold could be used for the ring mold biomass pellet machine.(4)The bionic ring model biomass granulator is used for granulation test,and the equipment runs smoothly and stably.A series of performance tests such as density,shattering resistance and deformation resistance were carried out on the particles prepared by biomimetic ring molding biomass particle machine.The results show that the properties of the particles meet the relevant standards and are better than those prepared by ordinary ring molding. |
