Two-particle model of anaerobic solid state fermentation

• Published in: Water Science & Technology Vol. 41; no. 3; pp. 43 - 50
• Main Authors: Kalyuzhnyi, S, Veeken, A, Hamelers, B
• Format: Journal Article Conference Proceeding
• Language: English
• Published: England IWA Publishing 01.01.2000
• Subjects: Anaerobic digestion; Bacteria; Bacteria, Anaerobic - metabolism; Biodegradability; Biodegradation; Biodegradation, Environmental; Bioreactors; Capacity; Carbohydrates; Carbon dioxide; Computer Simulation; Computers; Diffusion; Dye dispersion; Environmental Technology; Fatty acids; Fermentation; Growth kinetics; Hydrogen; Interactions; Kinetics; Leachates; Mass; Mass transfer; Mathematical models; Metabolism; Methanogens; Microorganisms; Milieutechnologie; Models, Biological; Personal computers; Phase equilibria; Process controls; Reaction kinetics; Refuse Disposal - methods; Sectie Milieutechnologie; Sludge; Solid state; Solid state fermentation; Solutes; Stability; Stoichiometry; Sub-department of Environmental Technology; Time Factors; Volatile fatty acids; Volatile organic compounds; WIMEK
• ISBN: 9781900222266; 1900222264
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2000.0054

A structured mathematical model of anaerobic solid state fermentation (ASSF) has been developed. Since a stable ASSF requires addition of significant quantities of methanogenic seed sludge and mass-transfer limitation becomes important, the model postulates the existence of two different types of particles inside the fermenting solid mass--so-called "seed" particles with low biodegradability and high methanogenic activity and so-called "waste" particles with high biodegradability and low methanogenic activity. Any particle is assumed to be a completely mixed reactor and mass transfer of solutes between the particles is brought about by diffusion. The model includes multiple-reaction stoichiometry, microbial growth kinetics, material balances, liquid-gas interactions and liquid phase equilibrium chemistry. The theoretical model agrees on the qualitative level with existing experimental studies of ASSF. Hypothetical computer simulations are presented to illustrate the influence of biodegradability and mass transfer intensity on the stability of ASSF. On this basis, possible measures are proposed to prevent accumulation of volatile fatty acids inside the "seed" particles beyond their assimilative methanogenic capacity.