Study On The Theory Of Biomass Closed Compression Molding And The Design Of The Double-roll Briquetting Machine

Biomass briquette fuel is a kind of compact solid fuel,which is prepared by dehydration,crushing,forming and other processes.Biomass fuel has a calorific value equivalent to medium quality bituminous coal,so it is a clean and quality alternative to coal.With the reduction of primary energy,the use of biomass solid fuel will be more extensive.But at present the biomass briquette fuel production in China is still in the pilot and demonstration phase;molding equipment has problems such as poor performance,serious mold wear,high energy consumption and bad adaptability to raw material,which has become a bottleneck of scale and industrialized production of straw briquette fuel.Based on one of the Heilongjiang application technology research and development programs—“research on key technologies of 2t/h straw briquette fuel production line(GC13B603)",the paper is an attempt to research and design a new type of closed double-roll biomass briquetting machine to reduce energy consumption,prolong the service life of mold,and enhance adaptability to materials.It is believed to be of great significance for industrialized development of biomass briquette fuel and its technological progress.In this paper,theories are based on to study the biomass compression molding process,the characteristic curve of compression molding,the manner of compression molding and the main influence factors of biomass compression molding.Under the same conditions,the pressure required by the closed molding is less than that of the open molding.The effects of moisture content,particle size,molding pressure and compression time on biomass compression molding were analyzed by orthogonal experiment.Through theoretical research and structural mechanics analysis,key components of closed double-roll biomass briquetting machine,such as feeder,screw compressor,booster device,double roll extrusion device and chassis,are designed,thus completing the overall structural design of the close double-roll biomass briquetting machine.This molding structure is a combination of rolling friction and sliding friction which could reduce energy consumption.Finite element analysis method is used for static analysis of the key components of the closed double-roll briquetting machine.It is found that the components are weak in structure,so they are optimized and subject to static analysis again to verify the rationality of the design.The results show that the performance indexes such as productivity,energy consumption per ton,ratio of briquetting and briquetting density are all up to the industry standard.