The flow dynamics in a novel fast-turbulent fluidized bed (FTFB) with middle-upper expanding structure and two different ring-feeder internals (mixed and vortex ring-feeder) were studied to achieve a reduction in ...The flow dynamics in a novel fast-turbulent fluidized bed (FTFB) with middle-upper expanding structure and two different ring-feeder internals (mixed and vortex ring-feeder) were studied to achieve a reduction in gasoline olefin production, Compared with a conventional circulating fluidized bed, the novel FTFB displayed unique characteristics and advantages. A higher solids holdup and more uniform solids holdup distribution existed in the diameter-expanding region, especially for the FTFB with vortex ring-feeder structure, A probability density distribution analysis indicated that the novel fluidized bed could reduce gas-solids segregation and enhance gas-solids interaction. A constant carbon dioxide tracer system was used to simulate the reactant gas distribution. The gas-solids contact efficiency was defined according to the solid dispersibility and the amount of gas covering the solid surface. Novel FTFB risers, especially those with vortex ring-feeders, have a much higher gas-solids contact efficiency than that of traditional risers.展开更多
基金the financial support of the CNPC in the National Program on Key Basic Research Project(973 Program) of China(No.2012CB215000)
文摘The flow dynamics in a novel fast-turbulent fluidized bed (FTFB) with middle-upper expanding structure and two different ring-feeder internals (mixed and vortex ring-feeder) were studied to achieve a reduction in gasoline olefin production, Compared with a conventional circulating fluidized bed, the novel FTFB displayed unique characteristics and advantages. A higher solids holdup and more uniform solids holdup distribution existed in the diameter-expanding region, especially for the FTFB with vortex ring-feeder structure, A probability density distribution analysis indicated that the novel fluidized bed could reduce gas-solids segregation and enhance gas-solids interaction. A constant carbon dioxide tracer system was used to simulate the reactant gas distribution. The gas-solids contact efficiency was defined according to the solid dispersibility and the amount of gas covering the solid surface. Novel FTFB risers, especially those with vortex ring-feeders, have a much higher gas-solids contact efficiency than that of traditional risers.