Gas Hold-Up and Mass Transfer in Three Geometrically Similar Internal Loop Airlift Reactors Using Newtonian Fluids

作者：Cerri Marcel Otavio^*; Policarpo Lucas Makrakis; Badino Alberto Colli

来源：International Journal of Chemical Reactor Engineering, 2010, 8: A14.

• airlift
• hold-up
• oxygen transfer
• k(L)a
• scale-up

Global gas hold-up and volumetric oxygen transfer coefficient (k(L)a) were evaluated in three internal-loop airlift reactors (ALR) with different working volumes (2, 5, and 10 dm(3)) and similar geometric configuration utilizing eight Newtonian fluids. Superficial gas velocity in the riser (UGR) was ranged from 0 to 0.112 ms(-1). The effects of the superficial gas velocity (UGR) and liquid viscosity had contrary effects on k(L)a. However, they presented the same order of magnitude showing that the viscosity effect on the oxygen mass transfer cannot be neglected. Two correlations based on dimensional analysis relating global gas hold-up and k(L)a to the geometric parameters, physical properties of the fluids, and operational conditions were proposed. Very good fittings between calculated and experimental data of and k(L)a were obtained. The influence of the internal diameter of the reactor on k(L)a was considered positive showing that in large-scale reactors an appropriate oxygen transfer can be reached under smaller aeration conditions, due to higher internal diameter.

• 出版日期2010