Experimental analysis of the chosen parameters effects on a gas hold up for mechanically agitated two- or three-phase systems

Magdalena Cudak,

Joanna Cieślik


In the paper, the analysis of the chosen parameters effects (gas flow rate, the impeller speed, type of impeller and concentration of the aqueous solutions of sucrose) on the gas hold-up for gas-liquid and gas-liquid--biophase systems mechanically agitated are presented. Experimental studies were conducted in a vessel of the diameter of 0.288 m. The agitated vessel was equipped with Rushton or A 315 impeller. The results were described mathematically. The study shows that gas hold-up strongly depends on the impeller speed and the gas flow rate.

Słowa kluczowe: mixing, hold-up, gas-liquid-biophase systems

Stręk F., Agitation and agitated vessels (in Polish), WNT, Warszawa 1981.

Bouaifi M., Hebrard G., Bastoul D., Roustan M., A comparative study of gas hold-up, bubble size, interfacial area and mass transfer coefficients in stirred gas–liquid reactors and bubble columns, Chemical Engineering and Processing, 40, 2001, 97-111, DOI: 10.1016/S0255-2701(00)00129-x.

Kamieński J., Niżnik J., Gas hold-up for gas-liquid system agitated with dual impellers, Inżynieria Chemiczna i Procesowa, 3C, 2001, 591-597.

Kamieński J., Niżnik J., The impact of the second impeller on the effects of gas dispersion in liquid, Inżynieria i Aparatura Chemiczna, 41(33), 2002, 335-336.

Alves S.S., Maia C.I., Vasconcelos J.M.T., Experimental and modeling study of gas dispersion in a double turbine stirred tank, Chemical Engineering Science, 57(3), 2002, 487-496, DOI: 10.1016/S0009-2509(01)00400-6.

Moucha T., Linek V., Prokopowa E., Gas hold-up, mixing time and gas-liquid volumetric mass transfer coefficient of various multiple configurations: Rushton turbine, pitched blade and techmix impeller and their combinations, Chemical Engineering Science, 58(9), 2003, 1839-1846, DOI: 10.1016/S0009-2509(02)00682-6.

Kamieński J., Agitation of multiphase systems (in Polish), WNT, Warszawa 2004.

Karcz J., Siciarz R., Bielka I., Gas hold-up in a reactor with dual system of impellers, Chemical Papers, 58, 2004, 404-409.

Adamiak R., Experimental studies of conditions for gas dispersion in liquid in the stirred tank on different scale (in Polish), Praca doktorska, Politechnika Szczecińska, Szczecin 2005. Shewale S.D, Pandit A.B., Studies in multiple impeller agitated gas-liquid contactors, Chemical Engineering Science, 61(2), 2006, 489-504, DOI: 10.1016/j.ces.2005.04.078.

Montante G., Horn D., Paglianti A., Gas-liquid flow and bubble size distribution in stirred tanks, Chemical Engineering Science, 63, 2006, 2107-2118. DOI: 10.1016/j.ces.2008.01.005.

Montante G., Paglianti A., Magelli F., Experimental analysis and computational modeling of gas-liquid stirred vessels, Chemical Engineering Research and Design, 85, 2007, 647-653, DOI: 10.1205/cherd06141.

Martin M., Montes F.J., Galan M.A., Bubbling process in stirred tank reactors I: Agitator effect on bubble size, formation and rising, Chemical Engineering Science, 63, 2008, 3223-3234, DOI: 10.1016/j.ces.2008.03.028.

Ahmed S.U., Ranganathan P., Pandey A., Sivaraman S., Computational fluid dynamics modeling of gas dispersion in multi impeller bioreactor, Journal of Bioscience and Bioengineering, 109(6), 2010, 588-597, DOI: 10.1016/j.jbiosc2009.11.014.

Cudak M., Process characteristics for the mechanically agitated gas-liquid systems in the turbulent fluid flow, Przemysł Chemiczny, 90(9), 2011, 1628-1632.

Fasano J.B., Myers K.J., Janz E.E., Effect of geometric variations on the performance of gas dispersion impellers with semicircular blades, The Canadian Journal of Chemical Engineering, 89, 2011, 961-968, DOI: 10.10.02/cjce.20459.

Major-Godlewska M., Karcz J., Gas hold-up in a tank equipped with the impeller and vertical tubular baffles, Inżynieria i Aparatura Chemiczna, 4, 2011, 20-21.

Major-Godlewska M., Karcz J., Process characteristics for gas-liquid system agitated in a vessel equipped with a turbine impeller and tubular baffles, Chemical Papers, 65, 2011, 132-138, DOI: 10.2478//S11696-010-0080-0.

Major-Godlewska M., Karcz J., Agitation of a gas-solid-liquid system in a vessel with high Speer impeller and vertical tubular coil, Chemical Papers, 66(6), 2012, 566-573, DOI: 10.2478/ s11696-012-0148-0.

Yianatos J., Contreras F., Diaz F., Gas hold-up and RTD measurement in an industrial flotation cell, Minerals Engineering, 23, 2010, 125-130, DOI: 10.1016/j.mineng.2009.11.003.

Vinnett Z., Contreras F., Yianatos J., Gas dispersion pattern in mechanical flotation cells, Minerals Engineering, 26, 2012, 80-85, DOI: 10.1016/j.mineng.2011.11.003.

Libudzisz Z., Kowal K., Żakowska Z., Technical microbiology (in Polish), PWN, Tom 2, Warszawa 2008.

Garcia-Ochoa F., Gomez E., Bioreactor scale-up and oxygen transfer rate in microbial processes: An overview, Biotechnology Advances, 27, 2009, 153-176, DOI: 10.1016/j. biotechadv.2008.10.006.

Gill N.K, Appleton M., Baganz F., Lye G.J., Quantification of power consumption and oxygen transfer characteristics of a stirred miniature bioreactor for predictive fermentation scale-up, Biotechnology and Bioengineering, 100, 2008, 1144-1155, DOI:10.1002/bit 21852.