SCI和EI收录∣中国化工学会会刊

›› 2017, Vol. 25 ›› Issue (9): 1143-1152.DOI: 10.1016/j.cjche.2017.03.010

• Fluid Dynamics and Transport Phenomena • 上一篇    下一篇

Gas-liquid flow mass transfer in a T-shape microreactor stimulated with 1.7 MHz ultrasound waves

Mona Akbari, Masoud Rahimi, Mahboubeh Faryadi   

  1. CFD Research Center, Chemical Engineering Department, Razi University, Kermanshah, Iran
  • 收稿日期:2016-08-10 修回日期:2017-03-04 出版日期:2017-09-28 发布日期:2017-10-11
  • 通讯作者: Masoud Rahimi,E-mail:m.rahimi@razi.ac.ir,masoudrahimi@yahoo.com

Gas-liquid flow mass transfer in a T-shape microreactor stimulated with 1.7 MHz ultrasound waves

Mona Akbari, Masoud Rahimi, Mahboubeh Faryadi   

  1. CFD Research Center, Chemical Engineering Department, Razi University, Kermanshah, Iran
  • Received:2016-08-10 Revised:2017-03-04 Online:2017-09-28 Published:2017-10-11

摘要: This paper describes the application of ultrasound waves on hydrodynamics and mass transfer characteristics in the gas-liquid flow in a T-shape microreactor with a diameter of 800 μm. A 1.7 MHz piezoelectric transducer (PZT) was employed to induce the vibration in this microreactor. Liquid side volumetric mass transfer coefficients were measured by physical and chemical methods of CO2 absorption into water and NaOH solution. The approach of absorption of CO2 into a 1 mol·L-1 NaOH solution was used for analysis of interfacial areas. With the help of a photography system, the fluid flow patterns inside the microreactor were analyzed. The effects of superficial liquid velocity, initial concentration of NaOH, superficial CO2 gas velocity and length of microreactor on the mass transfer rate were investigated. The comparison between sonicated and plain microreactors (microreactor with and without ultrasound) shows that the ultrasound wave irradiation has a significant effect on kLa and interfacial area at various operational conditions. For the microreactor length of 12 cm, ultrasound waves improved kLa and interfacial area about 21% and 22%, respectively. From this study, it can be concluded that ultrasound wave irradiation in microreactor has a great effect on the mass transfer rate. This study suggests a new enhancement technique to establish high interfacial area and kLa in microreactors.

关键词: Ultrasound waves, Microreactor, Gas-liquid flow, Mass transfer, Absorption

Abstract: This paper describes the application of ultrasound waves on hydrodynamics and mass transfer characteristics in the gas-liquid flow in a T-shape microreactor with a diameter of 800 μm. A 1.7 MHz piezoelectric transducer (PZT) was employed to induce the vibration in this microreactor. Liquid side volumetric mass transfer coefficients were measured by physical and chemical methods of CO2 absorption into water and NaOH solution. The approach of absorption of CO2 into a 1 mol·L-1 NaOH solution was used for analysis of interfacial areas. With the help of a photography system, the fluid flow patterns inside the microreactor were analyzed. The effects of superficial liquid velocity, initial concentration of NaOH, superficial CO2 gas velocity and length of microreactor on the mass transfer rate were investigated. The comparison between sonicated and plain microreactors (microreactor with and without ultrasound) shows that the ultrasound wave irradiation has a significant effect on kLa and interfacial area at various operational conditions. For the microreactor length of 12 cm, ultrasound waves improved kLa and interfacial area about 21% and 22%, respectively. From this study, it can be concluded that ultrasound wave irradiation in microreactor has a great effect on the mass transfer rate. This study suggests a new enhancement technique to establish high interfacial area and kLa in microreactors.

Key words: Ultrasound waves, Microreactor, Gas-liquid flow, Mass transfer, Absorption