For a gas-liquid dispersion with a gas hold-up of 0.1 and bubble diameter of 0.5 mm, the interfacial area per unit volume (in m2/m3) is_________________?
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Answer: A. 500
Explanation
Interfacial area per unit volume in a dispersion is given by six times gas hold-up divided by bubble diameter. Multiplying hold-up of zero point one by six and dividing by zero point five millimeters yields five hundred. This calculated specific surface area maximizes mass transfer rates in multi-phase reactor systems. Gas hold-up represents the volumetric fraction of gas bubbles dispersed throughout a continuous liquid phase. Bubble diameter determines the surface area available for mass transfer per unit volume of dispersion. Specific interfacial area is a critical parameter in designing gas-liquid reactors and bubble columns.
Bioreactors rely on high interfacial area to supply dissolved oxygen efficiently to microbial cultures. Chemical hydrogenation reactors use fine gas dispersions to accelerate mass transfer limited reactions. Wastewater aeration basins monitor bubble size and hold-up to ensure effective oxygen dissolution. Twelve hundred overestimates the interfacial area by miscalculating the bubble diameter and hold-up ratio. Nine hundred represents an incorrect mathematical combination of the given gas-liquid dispersion parameters. Eight hundred fails to match the exact geometric calculation derived from the specific surface area formula.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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