The following results were obtained by conducting a flow experiment. The experiment with air volume showed that the ducts with 3 shapes in the same cross-sectional area were large in the order of circular duct, square duct, and flexible duct. As a result of measuring the pressure value by duct shape to determine the cause of the difference between the flow rate and the air volume value by duct, the negative pressure was large in the order of circular duct, square duct, and flexible duct. in the countercurrent test, In the case of circular ducts, the deviation was high, In the case of Flexible ducts, the mild increase in the countercurrent is judged to be the difference in pressure and friction received by shape.

Domestic sewerage treatment plant is operated by activated sludge method and its modified method by using microorganism. In most cases, a method of using microorganism is directly controlled by the operator based on individual judgment through factors of DO, pH and ORP. In addition, under aerobic condition in bioreactor, energy consumption including excessive air injection is learned to be somewhat plenty. In order to solve this problem, in most of the process, improvement of internal recycling and activated environmental factor of microorganism were researched extensively. However, as factors are changed depending on various conditions, it is not sufficient as an indicator of judgment. As such, a research on operation of bioreactor that measures metabolic change in short time by directly measuring activated condition of microorganism using NADH fluorometer is required in reality.It is considered that the method like this could supplement problem of energy consumption being occurred in the existing treatment method and operational optimization of bioreactor would be enabled by controlling optimal air volume. Therefore, in this study, in order to obtain optimal operational indicator of bioreactor, proper air volume control test was performed and through batch test and site evaluation, possibility of NADH sensor being utilized as operational control indicator of bioreactor is intended to be analyzed. In order to compare with measured value, DO, ORP that are operational control indicator of existing bioreactor were used. As MLSS concentration was increased through batch test, NADH value was increased and site evaluation also showed similar tendency to batch test. Resultantly, it could be confirmed that changing level of NADH fluorometer was a sensor that could measure bioreactor condition effectively and optimized scale of bioreactor is considered to be utilized.