Investigation And Design Of New Type Of Flat Die Biomass Briquetting Machine

With the continuous consumption of resources and the serious pollution of conventional energy to the environment,people are aware of the necessity and urgency of developing new clean energy.As a renewable energy,biomass energy has great value in research and development.Development and utilization of biomass fuels,one of the important measures to protect the environment in today's society,has great prospects for development.In this thesis,chopped corn stalks after processing are treated as the research object.Based on in-depth analysis of the influencing factors of biomass briquetting,the main factors are obtained.And on this basis,the designed experiments have been carried out.By using mold with different sizes of independent design and the experimental method,the thesis explored the main influencing factors of forming biomass fuel.The influence of factors on the quality of biomass fuel,such as particle size,moisture content,aspect ratio,taper,length of mould pressure-holding,was investigated by experiments.By measuring the density and observing the surface quality of biomass briquette,the best parameters of forming process are following,preheating temperature of 80?,molding pressure about 10 MPa,mould taper at 10 degrees,moisture content on 16%,the pressure hole length about 30 mm.And the ratio of mold length to diameter is 5:1.Mold material the particle size is less than or equal to 3.5mm.In this condition,the quality of briquette is the best.Shatter resistance and physical properties and water resistance of the performance of biomass briquetting from experiment were tested and researched by shatter test and water permeability test.The purpose is test the performance of the biomass briquetting in the actual situation of transportation and storage.The formation mechanism of biomass fuel was analyzed and studied.The micro morphology of biomass briquetting was observed by scanning electron microscope(SEM).And the description of its forming mechanism are explored from the micro perspective.The microstructure of the cross section and longitudinal section of biomass fuel under different conditions were compared,and the optimum forming process was explored.On the basis of the optimum process conditions obtained by experiment and the research on the forming mechanism and microscopic appearance of biomass fuel,a new type biomass flat molding forming machine was designed.The flat die plate of the forming machine was designed as inclined plane,which is favorable for the uniform distribution of the material on the flat mould plate.And the flat plate was designed into a double side symmetry,which improves the utilization ratio of the flat mould plate.The parallel indexing cam mechanism was used as a cutting device for intermittent cutting of fuel.The three pressure rollers were designed to work simultaneously,which greatly improved the production efficiency.At the end of the shaft of the roller,the rack and pinion mechanism was used,which provides accurate meshing between the convex die of pressure roller and the concave die of the flat die,and improved the running efficiency of the molding machine.The digital prototype of the designed forming machine was established by using 3D software Creo.The forming process of the biomass fuel in a single mold hole was simulated by using the finite element analysis software ANSYS.Through analyzed the stress distribution of die and material in the process of forming,conclusion was provided for reference for optimization of biomass fuel molding process and mold.Based on the S-N curve of 40 Cr steel and its damage mechanism,the fatigue life of flat die plate was analyzed by using Fatigue Tool of ANSYS Workbench.This subject carried out theoretical analysis,experimental test and numerical simulation based on the study of biomass fuel forming.It provides reference for the optimization of biomass fuel and the development of biomass fuel molding equipment.