Stirring-bed Fast Pyrolysis Reactor Design And Experiment Research

Fast pyrolysis is a cracking reation in which macromolecule of biomass is broken into small molecular in moderate temperature and high heating speed. The process is regarded as one of the most perspective means of exploitation low valued biomass by thermal method.Pyrolysis reactor is the most important equipment in the process. A new type called stirring-type fast pyrolysis reactor was developed based on fast pyrolysis characteristics which have fast heat transfer, fast heating of materials, product out fast and fast condensation. The fast pyrolysis reactor has low manufacture cost and operating fee besides more stable performance.(1)2kg/hr laboratory scale pyrolysis reactor had been designed, processed and debugged by this thesis. Two stage cooling system composed of1st quench stage and2nd cooling heat exchanger was designed which was proven effective in avoiding secondary cracking of biomass oil. The disadvantage of tar adhering to the surface of heat exchanger had been avoided by condenser system.(2)Unsteady heat transfer model of the new reactor is established and solved by unsteady heat conduction equation, which give conclusion on minimum agitating speed and therefore, provide basic theoretical foundation.(3) The optimum operating process of reaction temperature, stirring speed and feed speed had been determined, which is500℃,95r/min and35r/min, respectively.(4) The organic content of fast pyrolysis oil is influenced by temperature, stirring speed and feed speed. Water content of fast pyrolysis oil is decreased by distillation. Distillation oil had same organic components which compared to pyrolysis oil.