GASEOUS CONCENTRATION GRADIENTS IN TRAY TYPE SOLID-STATE FERMENTERS - EFFECT ON YIELDS AND PRODUCTIVITIES

In aerobic solid state fermentation systems, interaction of mass transfer effects with bioreaction plays an important role on the yields and productivities of the bioreactors. Experimental observations on the oxygen and carbon dioxide concentration gradients in a tray type solid state fermentation system are reported in this paper. Steep gradients are experienced in deep beds making large portions of the bioreactor ineffective. The results are useful in the design of the bioreactor in terms of efficient mass transfer as well as critical thickness of the substrate bed to be used.