Journal of Chemical Engineering of Japan

Multiphase Contactors: New Approaches and Measurement Techniques for Characterization of Their Performance Under Various Operating Conditions

Multiphase contactors (especially bubble columns (BCs)) are the most widely used reactors in the chemical and biochemical industries. These important units are being used in various processes like gas absorption (with/without chemical reaction), oxidation, chlorination, alkylation, hydrogenation, fermentation, methanol and Fischer-Tropsch syntheses, waste water treatment, etc. BCs are characterized with a simple construction (lack of moving parts), excellent mass (MT) and heat transfer characteristics, operational versatility, and low pressure drop. In spite of their simple construction, the BC hydrodynamics are rather complex due to the formation of various flow regimes (homogeneous, transition, heterogeneous and slug). In multiphase contactors equipped with a perforated plate gas distributor (GD), a gas maldistribution is formed. It should be avoided since it is detrimental (due to formation of dead zones) for the multiphase contactor performance. For this purpose, more effective GDs for MT enhancement should be designed. The dependence of the liquid turbulence on GD should be analysed.

The multiphase contactors are the most important chemical reactors. Most industrially important chemical reactions are performed in these units. Several important theories (for instance, the penetration model or local isotropic turbulence theory) have been validated in gas-liquid contactors. The three-phase reactors find more industrial applications. Multiphase contactors with internals (for heat removal) are also gaining more interest. The effect of the perforated plate gas distributors (GDs) on the formation of dead zones should be carefully investigated. In addition, the effect of the different GD types (perforated plate, porous plate and cross sparger) on the degree of liquid turbulence should be studied. The volumetric liquid-phase mass transfer coefficients in the various gas-liquid contactors and systems should be compared and the most effective gas-liquid reactor should be recommended. It should be discussed how the Sauter-mean bubble diameter in gas-liquid contactors with internals should be estimated. It is important to check whether the local isotropic turbulence theory is capable of predicting the heat transfer coefficients under high pressure.

In this Article Collection, the subtopics of hydrodynamics (gas holdup prediction, flow regime identification, etc.), gas and liquid mixing, mass transfer (without and with chemical reaction) and heat transfer as well as liquid turbulence in multiphase contactors will be discussed. It is expected that the effects of both high pressure and temperature on these subtopics will be discussed. The hydrodynamics and mass transfer in gas-liquid contactors operated with aqueous solutions of alcohols, salts and sugars will be investigated. Topics in the field of bubble columns, airlift reactors, agitators and stirred tanks will be discussed.

It is expected that this Article Collection will contain 2 review papers, 4-5 full-length articles and 2 short communications.

Keywords: Bubble columns; Slurry bubble columns; Airlift reactors; Agitators; Stirred tanks

­­All manuscripts submitted to this Article Collection will undergo a full peer-review; the Guest Advisor for this Collection will not be handling the manuscripts (unless they are an Editorial Board member).

Please review the journal scope and author submission instructions prior to submitting a manuscript.

The deadline for submitting manuscripts is [October 31, 2025].

Please contact Prof. Stoyan Nedeltchev OR Zhan Yu at zhan.yu@taylorandfrancis.com with any queries and discount codes regarding this Article Collection.

Please be sure to select “Multiphase Contactors: New Approaches and Measurement Techniques for Characterization of Their Performance Under Various Operating Conditions” from the drop-down menu in the submission system.

Prof. Nedeltchev is an expert in bubble column reactors, nonlinear chaos theory and information entropy theory. He has published 61 peer-reviewed articles and 3 book chapters in this field. In addition, he has delivered 68 presentations at international Conferences and 27 invited talks at different institutions around the World. Prof. Nedeltchev has prepared 180 reviews for leading Chemical Engineering journals. He has received several prestigious fellowships and grants from the Fulbright Commission (USA), Alexander von Humboldt Foundation and DAAD (Germany) as well as Marie Curie Fellowship from the EU. He has been a Guest Editor or co-Editor of 5 Special Issues in the journals “Chemical Engineering Research and Design”, “Processes” and “Fluids”.