Abstract
An activated sludge system is a method which uses microbial function. Therefore, the number of microbes or microbial species in the system might be reflected on the quality of the final effluent. The level of microorganisms in the activated sludge system with filter membrane for swine wastewater was counted, and the relationship between the level of microbes in the aeration tank and quality of the final effluent was studied. Significant positive relationships between the pH in the aeration tank and the quality of the final effluent (biochemical oxygen demand ; BOD, chemical oxygen demand ; COD, total nitrogen ; T-N, ammonium nitrogen ; NH4-N and nitrite-nitrate nitrogen ; NOx-N) were observed. Significant relationships were obtained between the pH and the number of aerobes, denitrifying bacteria and eumycota in the aeration tank. Significant relationships were also observed between the level of BOD in the final effluent and the number of aerobes, anaerobes and denitrifying microbe in aeration tank. Positive relationships between the level of COD in the final effluent and the number of eumycota and actinomycetes were observed. The number of eumycota in the aeration tank was also reflected T-N and NH4-N on the final effluent. Negative relationships were obtained between NOx-N in the final effluent and denitrifying microbe, eumycota and iron-reducing microbes in the aeration tank. This study suggests that the number of some microorganisms in the aeration tank of activated sludge system for swine wastewater are reflected on the quality of the final effluent.
