Citric acid production is generally carried out in an aqueous medium stirred tank reactors (STR), where the solubility of oxygen low and demand microbial cultures high. Thus, for this bioprocess, providing adequate mass transfer rate (OTR) from gas phase into culture main challenge bioreactor selection operation. In study, citric by Yarrowia lipolytica W29 crude glycerol, batch cultures, was pe...

Models were developed for prediction and interpretation of the observed steady-state axial dissolved oxygen concentration profiles in tall airlift bioreactors. The observed concentration profiles were non-linear because of a combination of hydrodynamic and mass transport factors. The profiles were influenced mainly by the liquid-phase axial dispersion coefficient, the volumetric overall gas–liq...

The aim of this work is to use optimization as a tool for scale up in airlift bioreactors and apply this approach to a real life process. To put this approach into practice, Chlamydomonas reinhardtii, a green microalgae, was used as a model microorganism. The effects of the design parameters on the performance of the bioreactors were monitored through the changes in mixing and circulation times...

Effect of fractional gas hold-up εG on volumetric mass transfer coefficient KLa were studied for two different type of airlift contactors conventional and modified. KLa was directly proportional to gas hold-up within bubbly flow regime (UG < 0.075 m/s ) in conventional one but reverse trend ( inversely proportional) was reported in modified airlift contactor. Mathematical relation between KLa a...

Gas holdup and mixing time were characterized in a forced circulation internal loop draft-tube reactor (unaerated aspect ratio≈ 6, downcomero-riser cross-sectional area ratio = 0.493) as functions of the forced liquid superficial velocity in the riser (ULr) and the gas superficial velocity in he riser (UGr). Data were obtained in air–water system. The operation ranges were 0≤ULr ≤ 0.051 m/s and...

Cell Culture Bioreactors Basic Types of Bioreactors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 Stirred Tank (Well Mixed) vs. Tubular Reactor (Plug Flow) . . . . . . . . . . . . . . . . . 3 Segregated Bioreactors (Dead Zone Present) Compartmentalized Bioreactors . . 4 Implication When Growth or Reaction Occurs in the Reactor . . . . . ....

In the present work, removal of 4-chlorophenol (4-CP) by the mixed microbial consortium was evaluated in an airlift inner loop bioreactor. During the study, the effect of various reactor parameters such as hydraulic retention time (HRT), biogenetic substrate concentration, loading rate, and initial substrate concentration on the removal efficiency of 4-CP was investigated. Bioreactor showed a m...