Influence of pH, redox potential and hydraulic retention time on anaerobic fermentation of glucose

In wide ranges of pH, Eh and HRT values, glucose was anaerobically fermented by mixed anaerobes. Fastest specific glucose degradation rate and anaerobe growth rate were obtained under the conditions of pH(6(7 and Eh ( (400 mV. Product distribution was strongly influenced by pH, Eh and HRT. Lactate and acetate were always major products under all conditions, while ethanol, butyrate, formate and succinate could be major products under certain conditions. The effect of HRT on product distribution was not regular in a wide range of conditions. Under the conditions of pH(6 and Eh( (550~ (300 mV, butyrate concentration was decreased and propionate concentration increased. The shift in product distribution was due to variation in the population of anaerobes and changes in metabolic pathways of the same group