A proposed biparticle fluidized-bed for lactic acid fermentation and simultaneous adsorption

A bioreactor configuration is proposed for simultaneous fermentation and separation of the desired product. The bioreactor consists of a columnar fluidized bed of immobilized microorganisms. Denser adsorbent particles are added to this column. These adsorbent particles fall through the bed, absorb the product, and are removed from the base of the columnar reactor. The system hydrodynamics and the separability of the two types of particles were confirmed for low-density gel beads. The addition of the adsorbent, activated carbon, to a fermentation of Lactobacillus delbreuckii absorbed lactic acid. The addition of adsorbent enhanced the fermentation and controlled the pH.