Study On Combustion Mechanism Of Biomass Briquettes Combustion

With the growing energy crisis, biomass as a renewable energy by the growing attention ,around the world are putting in a lot of manpower, material development and utilization of biomass energy. China is a large agricultural country, Crop stalks resource is abundant in the country. , Biomass combustion is a biomass use way , as an effective way of using biomass is gradually being accepted; effective use of biomass energy, which is one of the important ways to solver energy crisis, and also leads to good economic, environmental and social benefits. Biomass compact molding technology has matured, but the technology of biomass briquettes combustion equipment is still immature. Mainly due to biomass fuel combustion mechanism of forming non-depth, which leads to selection inaccurate design parameters of boiler,and affect the shape of biomass fuel combustion efficiency, thereby affecting the popularization and application of molding equipment.Accordingly, we put forwardthe subject of the Study on Combustion Mechanism of Biomass Briquettes Combustion. Research from the analysis of characteristics of biomass briquettes to start, to find different biomass briquettes structural characteristics, test and analysis of biomass briquette burners, combustion process and combustion dynamics. The study concerns the burning of biomass briquettes efficient use of the base and biomass briquette combustion equipment, processing equipment and provide the scientific basis for the design and operation. Through rigorous scientific testing and careful, accurate data processing, the main contents and conclusions are as follows:(1) The study of biomass briquette on the characteristics and composition , analyzed and found the two forming the fuel composition, and forming the structure on which fuel combustion characteristics. Sawdust briquette structure mainly cellulose, semi-fiber and lignin, lignin content was the largest of which, due to thermal decomposition of lignin in higher temperature range, resulting in pyrolysis temperature higher than that of corn straw briquette. Corn straw briquette internal cellulose and hemicellulose content of greater than lignin, resulting in a lower pyrolysis temperature range.(2) In different working conditions, through to the actual biomass briquette combustion experiments and analysis of biomass fuel combustion forming factors: fuel type, for the wind conditions. Which, for the wind conditions on the average biomass briquette combustion velocity is particularly significant.(3) The use of fuels made from biomass combustion mechanism of forming bench, biomass briquette combustion mechanism is analyzed by combining with dynamic thermogravimetric analysis (TG) and derivative thermogravimetry (DTG) on biomass pyrolysis response to a series of theoretical and experimental research. And using test data and corn straw briquette sawdust pyrolysis kinetic parameters were calculated using Origin and Excel software on the test data of a linear regression analysis of combustion kinetics parameters E and frequency factor A, established for the wood chips and corn straw briquette combustion kinetics model.(4) Through biomass briquette on the actual combustion process of observation and analysis, it suggested that the penetration and diffusion combustion is a static combustion. The combustion process can be divided into four major stages, followed by drying preheating stage, pyrolysis and combustion stage, fixed carbon burning phase and burnout stage. Which, in the pyrolysis and combustion stage including: fuel thermal decomposition, release of volatile matter and combustion, excessive phase, the surface of coke burning.