Biomass Briquetting's Characteristics And Finite Element Analysis

As the most important primary energy sources, fossil fuels are non-renewable energy which cause serious environmental pollution and ecological damage in the process of development and use.However,Biomass is an important renewable energy with large, widely distributed features.Its efficient conversion technology has received increased attention recently. Biomass briquetting technology can densify loose biomass, significantly improve the performance of biomass products as an effective way to use biomass energy.Its study has a profound significance to establish new field of energy.First of all, the background and present state of subject study were discussed. Then, the characteristics of large volume and low-energy density of biomass were introduced.According to analysis of the biomass compression and forming factors, the experiment of biomass moisture was taken that got the best moisture rate.The finite element method of ANSYS was firstly applied to analyse biomass hydraulic briquetting's deformation.The compression was divided into three phases.It put forward forming mechanisms in different compression stages.Biomass briquetting belongs to the scope of non-continuum mechanics which have a lot of theoretical imperfections and limitations.So it was considered as compressible continuum that the theory of plastic mechanics of continuum was applied to study compressible materials. Using biomass briquetting's criterion and taking into account of hydrostatic pressure, biomass elasto-plastic constitutive equation was built.Then,It analyzed bimasss compression process with finite element method,through the contact unit of TARGE169 and CONTA172 appropriately dealing with the contact problem between briquette material and die wall,also rational division of finite element mesh.The finite element simulation got rheological law that indicated the flow of biomass outer obviously lagging behind the center.Also through analysis of the stress-strain in compression process,it revealed their evolution and distribution law.Besides, the local large stress was analyzed, it showed cone angle of cavity die being stress concentration and equivalent strain increased with relative density in a certain trend. The law of the load changes was found in the biomass compression process. Accordingly,the research and analysis of compression provided good application and reference value with biomass compression process optimization. In the end, temperature on the impact of biomass briquetting was carried out which it came into the extrusion stage and maintaining the shape.Using two types of heating temperature with THERMAL module,it got temperature distribution in the biomass briquetting process.Result through temperature field analysis and comparison indicated that the condition of 250°C had an advantage with reasonable temperature distribution ,at the same time reducing energy consumption.