Gas Holdup and Overall Volumetric Absorption Coefficient in Bubble Columns with Suspended Solid Particles

Kato, Yasuo; Nishiwaki, Akio; Kago, Tokihiro; Fukuda, Takashi; Tanaka, Shigenobu

doi:10.1252/kakoronbunshu1953.36.1333

Cited by 15 publications

(19 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several researchers concluded that an increase in solids concentration generally reduced the gas holdup [32,43,60,[66][67][68][69]74]. Sada et al [69] also reported that for low solids loading (<5 vol.%), the behaviour of the slurry bubble column is close to that of a solid-free bubble column.…”

Section: Solid Concentrationmentioning

confidence: 99%

“…Contrarily, Kara et al [66] found a strong dependence of gas holdup on solids concentration at low solids concentrations. Kato et al [74] reported that the effect of solid concentration on gas holdup becomes significant at high gas velocities (>10-20 cm/s).…”

Section: Solid Concentrationmentioning

confidence: 99%

“…Many studies have been conducted to investigate the effects of particle size on gas holdup as well [66,69,74]. The influence of particle size has been found to depend on a number of factors including flow regime, gas velocity, liquid properties and slurry concentration.…”

Section: Solid Concentrationmentioning

confidence: 99%

See 2 more Smart Citations

Bubble column reactors

Kantarci

Borak

Ülgen

2005

Process Biochemistry

833

473

View full text Add to dashboard Cite

Section: Solid Concentrationmentioning

confidence: 99%

Section: Solid Concentrationmentioning

confidence: 99%

See 1 more Smart Citation

Bubble column reactors

Kantarci

Borak

Ülgen

2005

Process Biochemistry

833

473

View full text Add to dashboard Cite

“…Previous investigations of hydrodynamics in a slurry bubble column have rarely measured bubble size (Shah et al, 1985a;Smith et al, 1984;Kato et al, 1973), even though this hydrodynamic parameters is of utmost importance for determining mass transfer to accomplish reliable design and scale-up (Heijner and van't Riet, 1984).…”

Section: Introductionmentioning

confidence: 99%

Gas and solids behavior in a baffled and unbaffled slurry bubble column

et al. 1987

View full text Add to dashboard Cite

New data and analyses are presented for describing gas and solids behavior in a slurry bubble column. Axial solids concentration and bubble size distributions were measured in a 0.108 m ID slurry bubble column apparatus operated at steady state conditions. The column was operated with and without internal baffles. The slurry and gas superficial velocities ranged from 0.0077 to 0.009 m / s and from 0.031 to 0.24 m/s, respectively. The solid phase consisted of glass spheres in a narrow size range with a mean diameter of 96.5 pm; the liquid phase consisted of tap water.With a one-dimensional sedimentation-dispersion model, the data have been used to predict average solids loadings and axial distributions of the solids for specified operating conditions. Local bubble size and concentration measurements indicate that the slurry bubble column was operated in the churn-turbulent flow regime throughout the entire range of operating conditions used in this study. The impact of internal baffles and solids concentration on the gas and solids behavior is discussed.

show abstract

“…The transition to bubble slug flow in bubble columns generally occurs below 0.08 m/s superficial gas velocity (Taitel et al, 1980) at a maximum holdup between 20 and 25 vol. % gas (Eissa and Schugerl, 1975;Kelkar et al, 1984;Kato et al, 1973 represents an optimum operating condition, since above this gas rate bubble size is increased and holdup decreased due to the faster rising slug bubbles. In addition to doubling this optimum gas rate, the agitated column produced gas holdups in excess of two times that observed in the bubble column studies at the optimum gas rate.…”

Section: Gas Holdupmentioning

confidence: 99%

Use of an Oldshue‐Rushton extractor as a gas‐slurry contractor

Gray

1987

AIChE Journal

View full text Add to dashboard Cite

There are a substantial number of chemical engineering processes requiring the intimate contact of a gas with a liquid in which a finely divided solid is suspended. Present techniques often require extensive equipment and maintenance in order to obtain the desired product. In purely diffusive or mass transfer operations, such as those involving absorption of a gas into a slurry of an absorbent and subsequent adsorption of the dissolved gas, the equivalent of a countercurrent multistage operation will be required if an appreciable percent removal of solute gas from the feed mixture is expected. The multistage agitated column shown in Figure 1, originally designed by Oldshue and Rushton (1 952) for liquid-liquid extraction, was investigated for use as such a countercurrent gas-slurry contactor. Experimental Equipment and ProcedureThe column is a 0.1524 m dia., 13-stage, fully baffled, mechanically agitated vessel employing countercurrent flow of gas with a liquid-solid slurry. The stages are 0.0834 m in height and are formed by stainless steel annular baffles having a central opening of 0.0826 m dia. The top stage is 0.4752 m in height in order to allow space for liquid and solid feeding. Each stage was agitated with a 0.0508 m dia., six-blade, flat disc type turbine with blades 0.0127 m wide and 0.0095 m high.Work was done using water slurries of limestone, sulfur, coal, and PVC pellets of varying particle sizes. The solid properties of interest are listed in Table 1. The water slurries were premixed, and were fed and removed from the top and bottom of the column using constant-volume displacement Moyno pumps.Air, a t rates measured by a rotameter, entered the column through a side port in the bottom stage. As the air was being dispersed, the liquid level in the column was maintained by an overflow port in the top stage. No collection of air was necessary a t the top of the column.Volume samples of the slurry feed and discharge streams were measured, filtered, dried, and weighed to determine the solid volume percent of the two streams. Approximately five turnovers of the column were required before these samples became equal, indicating steady state conditions, a t which point the Moyno pumps and air inlet valves were shut down simultaneously. After clearing all the air from the column, the liquid level was recorded to determine the gas holdup by the bed expansion method. The holdup slurry was then removed, agitated to uniformity in a smaller tank from which samples were taken, and analyzed as above to determine the volume percent solid holdup based on the liquid and solid volume only. The uniformity of the mixture in the sampling tank was periodically checked by weighing the entire solid holdup removed from the column after oven drying for a number of runs for each solid used. The range of conditions studied within the 13-stage column are listed in Table 2.The mechanical power input, being a better indicator of the degree of mixing than the impeller speed, was also investigated using a geometrically similar three...

show abstract

Gas Holdup and Overall Volumetric Absorption Coefficient in Bubble Columns with Suspended Solid Particles

Cited by 15 publications

References 0 publications

Bubble column reactors

Bubble column reactors

Gas and solids behavior in a baffled and unbaffled slurry bubble column

Use of an Oldshue‐Rushton extractor as a gas‐slurry contractor

Contact Info

Product

Resources

About