With the tightened governmental regulation on the quality of effluent for the protection of water quality environment, it is required to develop technology for converting sewage treatment facilities designed to remove only organic matters to advanced treatment systems that can remove nitrogen and phosphorus. As one of solutions for this requirement, this study proposed Y-TURN process using a two step influents and upflowed reactor. This process minimizes civil engineering works, and can save power cost because there is no internal circulation. Using the process, which was named Y-TURN process, a pilot test was performed and its results were analyzed.
The pilot test show that this process was able to remove nitrogen and phosphorus as well as organic matter efficiently. The 80～90% of chemical oxygen demand(COD) were removed. In addition, about 80～90% of total nitrogen(T-N) was reduced. The total phosphorus(T-P) reduction averaged 92%.
The results of this study show that the Y-TURN process has performance and economic efficiency high enough to change the existing activated sludge process to an advanced treatment process.