Experiments have been conducted in a stirred,inverted-cone sparged 1701 tank, to investigate the effect ofsolids loading on k_La values for oxygen transfer from gasbubbles into a gold slurry. Slurries with different solids loadingranging from 18.5 wt percent to 47.4 wt percent were used. Awide range of superficial gas velocity was investigated from0.0014 cm/s (4 cc/s) to 1.4 cm/S (4000 cc/s). k_La values forboth clear water and slurries with different solids loading were compared.The results show that a significant effect of solids loading onk_La was observed when superficial gas velocity was greaterthan 0.14 cm/s. Compared with clear water, a decrease of about50 percent in k_La was produced with 40 wt percent solidsloading at 1.3 cm/s superficial gas velocity.The influence of superficial gas velocity on bubble size anddistribution was also examined. Oxygen mass transfer wasfound to decrease due to the transition from complete dispersionto flooding, which occurred at the same superficial gasvelocities (from 0.14 cm/s to 0.35 cm/s) for both clear water and slurries.
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