Study On The Characteristic Of Fixed Bed Bomass Oxygen Rich Gasification Process

Biomass gasification technology is one of the main solutions for utilizing biomass energy, it can transform the large molecular hydrocarbon into small molecular hydrocarbon fuel. Now, air gasification technology has been widely utilized, meanwhile, oxygen rich gasification technology is being paid more and more attention due to the advantages of obtaining medium heat value producer gas and expanding the application of the producer gas through the reforming of CO/H2.Based on the analysis on the status of air gasification and oxygen rich gasification technology for biomass, the comprehensive experiment study on the characteristics of air gasification and oxygen rich gasification technology for biomass has been carried out on a downdraft fixed bed gasifier. The experiment shows that with air as the gasification agent, the experiment has been carried out to study the impacts of different producer gas outputs, different reduction zone temperatures on the producer gas composition, the heat value of the producer gas is the highest when the producer gas output is 60Nm3/h; and the producer gas composition is the optimal when the reduction zone temperature is 900℃; meanwhile, the analysis on the influence of filling some charcoal at bottom of the gasifier has also been carried out.Oxygen was also be used as the gasification agent in the same gasification system for the experimental study on oxygen rich biomass gasification process, by comparison, the heat value of the producer gas from oxygen rich gasification is twice of that from air gasification, the advantage of oxygen rich biomass gasification obvious; also, the results have shown that the heat value and the quality of the producer gas could be improved along with the increasing the oxygen concentration, but, when the oxygen concentration reaches over 90%, the influence is slight; the experiment shows that the suitable temperature for gasification is around 1100℃and the suitable Equivalence Ration is 0.25~0.3for both air gasification and oxygen rich gasification. At last, the engineering technology for oxygen rich gasification has been analyzed, some suggestions for improving the equipment performance have been proposed; the two kinds of applications of oxygen rich gasification technology, which are for vehicle fuel application and for synthesizing of liquid fuel, have also been analyzed. The study could be helpful for the commercial use of fixed bed gasifier based oxygen rich gasification technology.