Recent studies have demonstrated that gradient copolymers exhibit unique properties.Although these properties ...
Yin-Ning Zhou,Jin-Jin Li,Zheng-Hong Luo Department of Chemical and Biochemical Engineering,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,P R China
Effects of some important structural parameters,i.e.slat pitch,and layout position,on dynamic forces acting on the baffles were examined in the fluidized bed of FCC particles operating under different superficial gas velocities.The experimental baffles were made of multiple inclined slats.We found that the forces acting on the baffles decreased significantly with reducing pitch between the slats.For the baffles with a small slat pitch,the forces acting on the baffles increased slightly and then decreased with increasing superficial gas velocity,which is very different from the measured results of a single slat or tube immersed in fluidized beds.The different results are greatly related to the appearance of the“gas cushion”beneath the baffles,whose height increases with increasing superficial gas velocity.On the other hand,a region with stronger particle circulation induced by the inclined slat array was observed in the experiments.The slat near the wall and located below the region of downward-flowing particles was found to be subjected to the severest forces.Therefore,the slats located in similar locations of industrial baffles are suggested to be reinforced to increase their structural strength.