Oxygen for a bioreactor

In Bio-reators using aerobic processes, optimal oxygen transfer is perhaps the most difficult task to accomplish. Oxygen is poorly soluble in fermentation broths. Oxygen transfer is usually helped by agitation, which is also needed to mix nutrients and to keep the fermentation homogeneous. There are, however, limits to the speed of agitation due to the damage to organisms caused by excessive tip speed. To improve the solubility of oxygen some processes may opt for using either enriched air or 90% oxygen from a VPSA oxygen generator.