The flow characteristics of a φ200 mm×2500 mm threephase continuous loop reactor with a draft tube were systematically investigated with glass beads as the solids phase,air as the gas phase and tap water as the liquid phase,respectivelyThe operating parameters,including superficial gas velocity,slurry feed velocity and inlet solids holdup in the range of interest in direct coal liquefaction,were varied to demonstrate their effects on the local distributions of gas and solids holdups and internal circulation slurry velocityThe local values of sectional average gas holdup in the draft tube increased with increasing superficial gas velocity,and decreased with increasing inlet solids loadingsVarying slurry feed velocity led to small effects on the local values and distributions of the sectional average gas holdup in the draft tube,while continuous feeding of slurry was helpful to the effective dispersion of gas phase and enhancing aeration in the annulusLocal slurry circulation velocities showed a parabolic profile in radial distribution with the lowest velocity at the central axis of the draft tubeThe slurry feed velocity and inlet solids loading had a small effect on slurry circulation,and the slurry circulation intensity defined as the ratio of circulating slurry velocity in the annulus to the feed slurry velocity was in a range [JP+3]of 20—180.The axial and radial distributions of solids holdup were spatially uniform in the reactor,and were affected by superficial gas velocity and slurry feed velocity..