Study of mixing in Airlift bioreactor used in (bio) leaching process

Mixing is one of the most important parameters for designing and modeling in Airlift bioreactors. This parameter is depended on mixing time (tm), circulation time (tc), the axial dispersion coefficient, gas hold up and Bodenstein number. In this article, these values were studies in an internal Airlift bioreactor in sand particles (3 phases) and tap water (2 phases). The results show, by increasing in aeration rate, tm and tc) are decreased but ez is increased. Measurements were reported in sand particles (3 phases) and tap water (2 phases), as used in (bio) leaching process. /These values compared with mathematical model Ez = Kd(u gr e gr ) [1,2] and the obtained values have difference in 2 phases and 3 phases mode, 12% and 20% respectively. Also, the obtained values for 􀟚 and 􀟛 in equation Bo􀭐􀭋 = /β(Fr 1/3)n [3] with experimental values fitting (bo lg and fr 1 3) for 2 phases mode 6.1 and 1.047, for 3 phases mode 5.5 and 0.97 respectively.