Abstract: The circulation time of particles is an important parameter describing the fluidization quality in fluidized bed.A new method for the measurement of circulation time of particles in fluidized bed based on the electromagnetic induction of the moving charges was proposed，and a detection model of electrostatic induction sensor was established.The experimental study showed that the relationship between the dominant frequency of electrostatic fluctuations and the circulation time of particles was T_e=5.668/f₀ at different superficial gas velocities between 0.12 m·s^-1 and 0.48 m·s^-1.The correlation coefficient between the experimental results and the model results was 0.9765，and the value of the root mean square error of prediction (RMSEP)was 0.0241.Thus，a simple，safe and precise method to determine the circulation time of particles applicable to the online measurement was presented.

Key words: electrostatic induction, gas-solids fluidized bed;circulation time of particles, Fourier transform, dominant frequency

关键词: 静电感应, 气固流化床, 颗粒循环时间, 傅里叶变换, 基频