The Experiment Study on the Void Fraction in PPG Solution

Abstract:

Using the three-layer impellers with big size diameter in an unbaffled elliptic bottom stirred tank，the gas holdup (ε) was studied in the systems of air-polyether polyol (PPG). The results indicate that the gas holdup in the air-PPG system is higher, it increase with the superficial gas phase velocity (V_s) and specific power input (P_m) increase, and decrease as the temperature increase. The influence is severely when the temperature is below 100°C, and is weak above 100 °C.The conclusions give reference for choosing the operation parameter and designing and scale-up of PPG polymerization reactor.

• Periodical: Advanced Materials Research (Volumes 455-456)
• Pages: 815-819
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.455-456.815
• Online since: January 2012
• Authors: Qian Qiao Chen, Qin Zhong, Li Qi, Qun Qun Cheng, Lu Wang, Miao Hu
• Keywords: Gas Holdup, Gas-Liquid, Multi-Impeller, Polyether Polyols, Temperature

References

[1] Cui Ying-chun, Shu Qing-yu, Zhang Zhen-hua, et al. Continuous Production Process of DMC Polyether Polyols[J], Chemical Propellants & Polymeric Material 2008，6(4)：57-59(Ch).

[2] Long Jiangang，Bao Yuyun，Gao Zhengming. Gas- liquid dispersion in a stirred tank with different impeller combinations[J]，Journal of Beijing University of Chemical Technology，2005，32 (5)：1-5（Ch）.

[3] Mariano M，Francisco J， Miguel A．Influence of impeller type on bubble breakup process in stirred tanks[J]．Ind Eng Chem Res，2008，47：6251-6263.

DOI: 10.1021/ie800063v

[4] Xu Shiai，Feng Lianfang，Guo Xueping，et al．Gas-liquid floating particle mixing in an agitated vessel [J]．Chem Eng Technol，2000，23(2)：103-113.

[5] Moucha T，Linek V，Prokopova E．Gas hold-up, mixing time and gas-liquid volumetric mass transfer coefficient of various multiple-impeller configurations: Rushton turbine, pitched blade and techmix impeller and their combinations[J]．Chem Eng Sci，2003，58 (9)：1839-1846.

DOI: 10.1016/s0009-2509(02)00682-6

[6] Smith J M，Gao Zhengming，STEINHAGEN H M．The effect of temperature on the void fraction in gas-liquid reactors [J]．Experimental Thermal and Fluid Science，2004，28 (5): 473-478.

DOI: 10.1016/j.expthermflusci.2003.06.004

[7] Bao Yunyu，Chen Lei，Gao Zhengming et al．Local void fraction.

[8] and bubble size distributions in cold-gassed and hot-sparged stirred reactors[J]．Chem Eng Sci, 2010，65(2)：976-984.

DOI: 10.1016/j.ces.2009.09.051

[9] Bao Yunyu，Gao Zhengming，Huang Xiaohua et al．Gas-liquid dispersion with buoyant particles in a hot-sparged stirred tank[J]．Ind Eng Chem Res，2007，46（20）：6605-6611.

DOI: 10.1021/ie070481w

[10] Chen Lei，Bao Yunyu，Gao Zhengming．Void fraction distributions in cold-gassed and hot-sparged three phase stirred tanks with multi-impeller[J]，Chinese Journal of Chemical Engineering，2009，17(6)：887-895.

DOI: 10.1016/s1004-9541(08)60293-1

[11] Liu Feiming , Lin Xinghua , Shi J ianqiang , et al. An Experimental Inve stigation on the Gas-Liquid Stirring Characteristics of the Combination Impellers[J]，Chemical Engineering & Machinery, 2004，31 (2)：67-70（Ch）.