- All Journals
- Al-Qadisiyah University
- Basrah University
- Kirkuk University
- Mosul University
- The Iraqi Borad for Medical Specialization
- University of Anbar
- University of Technology
- Al Mustafa University
- Al-Zahraa University for Women
- Alnoor University
- Kunooz University
- Misan University
- Ninevah University
- Tikrit University
- University of Al-Hamdaniya
- University of Kerbala
HYDRODYNAMICS OF A CONCENTRIC TUBES AIRLIFT REACTOR | ||
| DIYALA JOURNAL OF ENGINEERING SCIENCES | ||
| Article 40, Volume 3, Issue 0, 2010, Pages 427-444 PDF (0 K) | ||
| Author | ||
| Aseel Abd Aljabbar | ||
| Abstract | ||
| ABSTRACT:- In airlift reactors transport phenomena are achieved by pneumatic agitation and circulation occurs in a defined cyclic pattern through a loop. In the present work, the effect of geometrical relations on gas holdup and liquid velocity, and consequently on the gas-liquid mass transfer coefficient, was studied in a 15-liter airlift bioreactor with Ad/Ar = 0.224, Ad : downcomer cross-sectional area, and Ar : riser cross-sectional area. Measurements of the volumetric oxygen transfer coefficient (KLa) were taken in a raw water-air system using a sulfite oxidation method for depleting the oxygen to zero. The unsteady state concentration of oxygen is then measured using DO probe. Different conditions were examined by varying parameters such as superficial air velocity in the riser (Usg), using two types of air sparger which have a remarkable effect on KLa values. The effect is due to their influence on gas holdup and liquid velocity, consequently affecting KLa. Superficial air velocity in the riser (Usg) ranged from 0.03 to 0.06 m.s-1 and KLa varied between 0.01 to 0.07 s-1. Empirical equations were obtained between KLa and Usg as: KLa = 0.28 Usg 0.53 for cross sparger KLa = 0.58 Usg 0.86 for o-ring sparger Keywords:- Airlift, Bioreactor, hydrodynamics, oxygen mass transfer rate. | ||
| Keywords | ||
| Airlift; Bioreactor; Hydrodynamics; oxygen mass transfer rate | ||
|
Statistics Article View: 249 PDF Download: 183 |
||