Karimi - Biotechnology Group, Chemical Engineering Department, Faculty of Engineering, Tarbiat Modarres University, Tehran, Iran
Shojaosadati - Biotechnology Group, Chemical Engineering Department, Faculty of Engineering, Tarbiat Modarres University, Tehran, Iran
Hejazi - Biotechnology Group, Chemical Engineering Department, Faculty of Engineering, Tarbiat Modarres University, Tehran, Iran
Vasheghani Farahani - Biotechnology Group, Chemical Engineering Department, Faculty of Engineering, Tarbiat Modarres University, Tehran, Iran

Substrates become the packing particles in most solid-state bioreactors and they affect some of the operational parameters like porosity and pressure drop in packed bed bioreactors. In solid-state fermentations, the volume of packing particles changes during the process due to the utilization of substrate and production of biomass by microorganisms. Packing density will change as a result of these alterations. In this research, porosity of the packed bed was measured during solid-state fermentation of wheat bran using Raimbault laboratory scale packed bed bioreactors. Analyses have shown the increasing trend of these changes despite of pressure drop increment.

solid-state fermentation, laboratory scale packed bed bioreactor, porosity, particle density