The picture for moving behavior of gas bubbles in gassolid twophase fluidized bed had been taken by using high speed CCD

the coordinate of gas bubble’s centre being obtained through recognition of the gas bubble’s margin

the area and rising speed of the gas bubble being calculated. It was found from tests that the gas bubbles’ growup in rising course of the bed layer

and their rising speed became fast; the rising speed and generation frequency of gas bubbles increase along with the increament of gas flow; if the fluidized air velocity was higher

two or more gas bubbles may easily generated in the fluidized bed

and the phenomenon of gathering together for gas bubbles may occure.