Study On Characteristics Of Biomass Gasification And Tar Photocatalytic Cracking

With the development of research and application of biomass gasification technology,the influence of the character of biomass pyrolysis brings much more attention. It is found that the final pyrolysis temperature is the most important influencing factor during the process. When the final temperature is above 650℃,liquid phase(oil)achieved 50%. Gas production rate increases with the gasification temperature. Solid residue decreases with increasing temperature. Tar yield decreases with the increasing temperature when the temperature exceeds 650℃. The improving reaction temperature is beneficial to the gasification process with primary purpose of gasificationg.The different congtent of main component such as cellulose, hemicellulose, lignin and different organizational structure of biomass affect the pyrolysis and gasification characteristics of biomass in varying degrees. Pine has a higher content of cellulose and lower lignin content, so it has the highest gas rate, while has the corresponding least residue. Due to the higher content of cellulose and hemicelluloses, cotton stalk has a lowest gasification rate and highest solid rate. The lignin contents of sawdust, cotton stalk, small straw and corn stalks are in turn increase. Therefore, in descending order of solid residues are: corn stalk, cotton stalks, wheat, bar and sawdust. In the optical catalytic conditions, the macromolecular organic matter of the tar can be converted into CO2 and H2O. The composition of the product of pyrolysis tar is similar to the gas. So there is no significant effect on gas quality.According to the study of the thermalgravimetric curve, differential thermal analysis curve and differential thermalgravimetric curve, the pyrolysis of biomass shows the presence of three stages. The pyrolytic decomposition is a complex reaction. According to the pyrolysis kinetics analysis of biomass, the apparent pyrolysis reaction orders of pine, wheat straw, cotton stalk, and cornstalk can be considered to be around 1.0 and different biomass has different activation energy and different frequency factor.