Comparisons of the anaerobic treatment of soluble wastewaters using various configurations under mesophilic (35 degrees C) and thermophilic (55 degrees C) conditions

Anaerobic biotechnology is fast becoming an alternative for the treatment of wastewaters. Knowledge gained so far has shown the applicability of the anaerobic process system to different wastewaters. Most wastewaters contain various components of proteins, carbohydrates and fats. The treatment of these wastewaters has been enhanced by the use of different reactor configurations. A basic concept in the design of these reactor configurations is the immobilization of the biomass for the promotion of bacterial activity. The supply of inorganics as nutrient supplements is also important in anaerobic digestion.; The main objective of this research is to investigate anaerobic treatment with various reactor configurations for the treatment of various wastewaters containing combinations of proteins, carbohydrates and fats. The results revealed that the treatment of these wastewaters is very much dependent on reactor configuration as well as type of feed substrate. Acetic and propionic acids were the main volatile fatty acids associated with the lag times as well as the increases in the effluent CODs. Mesophilic reactors hardly displayed any lag time compared to the longer acclimation required by the thermophilic reactors. Volatile fatty acids were more predominant in the thermophilic reactors than in the mesophilic reactors. The failure of any reactor configuration was most likely attributed to the accumulation of both acetic and propionic acids.