m.a salehi - Faculty of Engineering, University of Guilan, P. O. Box ۳۷۵۶, Rasht- Iran
sh raiszadeh - Faculty of Engineering, University of Guilan, P. O. Box ۳۷۵۶, Rasht- Iran
n amanifard - Faculty of Engineering, University of Guilan, P. O. Box ۳۷۵۶, Rasht- Iran
z mirnezami - Faculty of Engineering, University of Guilan, P. O. Box ۳۷۵۶, Rasht- Iran

The hydrodynamic of internal reactors with a riser diameter of 4cm and 5cm operating with air and water system have been experimentally investigated for a range of superficial gas velocity. Herewe have used 2 internal loops with 4cm and 5cm internal diameter. For each velocity we havemeasured the gas hold up. The gas phased sparged in to the column by means of 4 different spargers with different number of holes in 1mm diameter. The results show that the gas distributerplays an important role on the evolution of the bubble size distribution in gas-liquid reactor. Soone of the main subjects of the present work is to study the influence of sparger design

Airlift, Internal reactor, Sparger, Gas hold up, Distribution