KLa
KLa KLa is the volumetric mass transfer coefficient, it consists of two terms “ KL” (mass transfer coefficient) and “ a” (Interfacial area of two different phases). Area “a” depends on size, shape and no of bubbles that depends on agitation speed and property of fluid these factor also affect K L. It is difficult to measure “ KL” and “ a” separately so both the terms are combined as KLa, having unit h -1 . KLa is used to determine aeration efficiency of bioreactor and quantifying the effect of variable operating parameters on dissolve oxygen. Three mass transfer situation occurs in bioprocessing: Gas to Liquid, Liquid to Liquid and Liquid to Solid In fermenter and Bioreactor oxygen transfer from supply air to cell taken place in three stages: 1) Transfer of oxygen from air bubble to solution/media 2) Transfer of dissolve oxygen from media solution to cell membrane 3) ...