Flow regimes in slurry bubble column: Effect of column height and particle concentration

Orvalho, Sandra; Hashida, Masaaki; Zedníková, Mária; Stanovský, Petr; Sasaki, Shohei; Tomiyama, Akio

doi:10.1016/j.cej.2018.06.115

Cited by 44 publications

(21 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This linear relationship between the superficial gas velocity and the gas hold-up agrees with several other studies. 56,[59][60][61][62][63] The most recent investigation of the gas hold-up in a BCR hydrocarbon bioprocess reported the same influence, whereby the gas hold-up linearly increased as the superficial gas velocity increased from 1 to 3 cm s −1 . 31 As the superficial gas velocity increases, the BCR would be operating within the homogeneous flow regime where the number of small bubbles increases in the column resulting in an increase in the gas holdup.…”

Section: Resultsmentioning

confidence: 83%

Gas–liquid interfacial area and its influence on oxygen transfer coefficients in a simulated hydrocarbon bioprocess in a bubble column reactor

Abufalgha

Pott

Cloete

et al. 2020

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

BACKGROUND The overall volumetric oxygen transfer coefficient (KLa) is a critical parameter in evaluating the oxygen transfer in any aerobic bioprocess, e.g. a hydrocarbon‐based bioprocess. However, KLa comprises the oxygen transfer coefficient (KL) and the gas–liquid interfacial area, which are commonly affected by operating conditions of a bioprocess system. Therefore, this study has experimentally measured KLa and interfacial area in a model hydrocarbon‐based bioprocess under a range of operating conditions such as alkane (n‐C14–20) concentration (HC), solids (cornflour) loading (SL) and superficial gas (air) velocity (UG) in a bubble column reactor (BCR). RESULTS It was found that the value of KLa increased with increasing UG in the BCR. The most significant impact on KLa was obtained through an increase in UG, where an increase of UG from 1 to 3 cm s−1 resulted in a 133% increase in KLa. Furthermore, a relationship between KLa and SL was identified and showed an optimal level at SL of 3 g L−1, indicating increased dispersion viscosity in the system as SL increased up to a certain point. However, HC showed an insignificant change in both the interfacial area and KLa with the range considered (2.5 to 20% v/v) of HC. CONCLUSIONS This study expands on previous work by including an inert solid (cornflour) phase, which ultimately furthers our understanding of the effect of the solids type and size, and operational conditions (HC, SL and UG) on the behaviour of overall oxygen transfer in a bubble column hydrocarbon bioprocess.

show abstract

Section: Resultsmentioning

confidence: 83%

Gas–liquid interfacial area and its influence on oxygen transfer coefficients in a simulated hydrocarbon bioprocess in a bubble column reactor

Abufalgha

Pott

Cloete

et al. 2020

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

show abstract

“…The gas holdup was high in this system and the reason may be that the metal sintered plate was used as the gas sparger. The gas sparger is important for the flow regime production [35] and can influence the flow regime transition points [36]. The metal sintered plate adopted is a ''fine sparger'' as mentioned by Orvalho et al [35], which can guarantee the occurrence of the four flow regimes.…”

Section: Impact Of Solid Volume Fraction On Total Gas Holdupmentioning

confidence: 99%

Impacts of Particle Properties on Gas Holdup under Four Flow Regimes in Three‐Phase Bubble Columns

Zhou²,

Sun

et al. 2021

Chem Eng & Technol

View full text Add to dashboard Cite

The impacts of the solid volume fraction V s and particle size d p on the total and local gas holdups in gas-liquid-solid bubble columns under different flow regimes were investigated. The flow regimes discussed were the discrete bubble regime (DBR), transition regime (TR), bubble coalescence regime (BCR), and strong turbulent regime (STR). The results demonstrated that the bed average gas holdup e g decreased with higher solid volume fraction in DBR, TR, and BCR. The increment of the solid volume fraction promoted bubble coalescence and also can enhance the particle effect on the average gas holdup. The e g changed slightly when shifting the V s or d p in STR. A new correlation for e g was developed considering the particle properties and the flow regimes studied.

show abstract

“…The particles were hydrophilic and were well dispersed in water. Orvalho et al 26) investigated the particle properties in detail. The particle size distribution had a dominant peak around 100 μm, and the mean diameter and the standard deviation were 103 μm and 15 μm, respectively.…”

Section: Experimental Setup and Conditionsmentioning

confidence: 99%

Experiments on Removal of Hydrophilic Fine Particles in Bubbly Flow

et al. 2019

Self Cite

View full text Add to dashboard Cite

It is commonly believed that the solid oxides, like aluminum inclusions, were easily removed by bubbles because of their poor wettability with molten steel. However the liquid oxides like ladle slags were hard to remove because of their good wettability. The purpose of this study was to reveal the removal rate coefficient of the hydrophilic particles, which simulated liquid oxides in molten steel, in bubbly flows. The water model experiments were carried out. The air was injected into water-particles mixtures in a rectangular tank and the amount of particles included in the mixture overflowed from the tank was measured. The experiments confirmed that bubbles have abilities to bring hydrophilic particles upward even though the particles do not adhere to the bubble interfaces. The hydrophilic particles are entrained into the bubble wake at a certain probability and dragged upward while riding on the liquid flow in the wake. The removal rate coefficient per a bubble increases with the bubble diameter whereas the increase in the number of bubbles deteriorates the efficiency due to the reduction of the wake volume which is effective for particle transportation.

show abstract

Flow regimes in slurry bubble column: Effect of column height and particle concentration

Cited by 44 publications

References 40 publications

Gas–liquid interfacial area and its influence on oxygen transfer coefficients in a simulated hydrocarbon bioprocess in a bubble column reactor

Gas–liquid interfacial area and its influence on oxygen transfer coefficients in a simulated hydrocarbon bioprocess in a bubble column reactor

Impacts of Particle Properties on Gas Holdup under Four Flow Regimes in Three‐Phase Bubble Columns

Experiments on Removal of Hydrophilic Fine Particles in Bubbly Flow

Contact Info

Product

Resources

About