A full-size numerical simulation of an airlift loop reactor with three types of different gas distributors was carried out.The standard κ-ε model and Euler multiphase flow model were used for the simulation of gas-liquid two-phase turbulent flow.All details of gas holdup and flow velocity distribution in the reactor were obtained.It was found that different gas distributor affected greatly global gas holdup and two-phase velocity in the inner tube

and consequently affected greatly gas holdup distribution and gas-liquid contact

which influenced the progress of reaction.The results showed that the contact of gas and liquid was poor with gas distributor of one loop.Gas distributors with multi-loops were recommended in big-diameter loop reactors.The computing results were compared with experimental data on global gas holdup and the agreement was satisfactory.