Mass transfer from single carbon-dioxide bubbles in surfactant-electrolyte mixed aqueous solutions in vertical pipes. (March 2020)

• Record Type: Journal Article
• Authors: Hori, Yohei; Bothe, Dieter; Hayashi, Kosuke; Hosokawa, Shigeo; Tomiyama, Akio
• Is Part Of: International journal of multiphase flow. Volume 124(2020)
• Publication Date: 2020-03
• Subjects: Sodium chloride -- Triton X-100 -- Sherwood number -- Surface tension; Multiphase flow -- Periodicals; Écoulement polyphasique -- Périodiques; Multiphase flow; Periodicals; 620.1064
• DOI: 10.1016/j.ijmultiphaseflow.2020.103207
• Languages: English
• ISSNs: 0301-9322

Abstract

Highlights: Combined effects of surfactant and electrolyte on mass transfer are studied. The combined effect of surfactant and NaCl differs from that of alcohol and NaCl. The presence of NaCl does not affect mass transfer if bubbles are fully-contaminated. A functional form of mass transfer correlation for Taylor bubbles is presented. Abstract: Mass transfer from single carbon-dioxide (CO2 ) bubbles rising through vertical pipes filled with surfactant−electrolyte mixed aqueous solutions was measured to study the combined effects of surfactant and electrolyte on the mass transfer. Triton X-100 and sodium chloride (NaCl) were used for surfactant and electrolyte, respectively. The surface tension, σ eq, at an equilibrium state decreased with increasing the concentration of NaCl at a constant concentration of Triton X-100. The pipe diameters were 12.5 and 18.2 mm. A wide range of bubble diameter covered various bubble shapes from ellipsoidal to Taylor bubbles. The combined effects of Triton X-100 and NaCl on the Sherwood number, Sh, showed a different trend from those of alcohol and electrolyte, i.e. bubbles in the Triton X-100−NaCl mixed aqueous solution were not fully-contaminated even with the same σ eq as in the condition fully-contaminated with Triton X-100, due to the difference in distributions of surfactant concentrations at the interface. The Sh of bubbles fully-contaminated with Triton X-100 were not affected by the presence of NaCl. The Sh of contaminated Taylor bubbles can be expressed as a combination of functional forms of available Sh correlations for clean and fully-contaminated Taylor bubbles.