Sewage from the small town Marines, in the Valencia region, Spain, is treated in a centralized wastewater treatment plant (WWTP). Secondary effluent from the plant is discharged into a dry gully near the plant. According to current EU directives regarding the collection and treatment of urban wastewater, in some cases WWTPs are required to remove nutrients (nitrogen and phosphorous) as part of their biological wastewater treatment (Table 1). The Marines plant was only designed for removal of organic carbon, and was not equipped with the components necessary for nutrients removal. In addition, the plant occasionally receives instantaneous peaks of organic load from the local food industry.
Upgrading a municipal WWTP using AGAR® technology
In view of EU directives for effluent discharge, it was required to upgrade the local sewage plant in the town of Marines, Valencia (Spain). The technology chosen for the project was AGAR® (Attached Growth Airlift Rector) of AqWise - Wise Water Technologies Ltd. La Entidad Pública de Saneamiento de Aguas Residuales (EPSAR) has promoted the implementation of the AGAR® system in the Valencian Region, whereas SAEM Enginyeria was chosen as a co-designer company for the system. For the installation of the process in the existing aeration tank, the plant had to be shut down for only five days. Effluent quality, as measured along two months following the upgrade project, complies with EU directives as planned.