AWWA MTC57633

The Georgia Department of Natural Resources Environmental Protection Division (EPD) has established limits for annual phosphorus load to several Georgia lakes. As a result, several wastewater treatment plants in metro Atlanta have received a 0.13-mg/L effluent total phosphorus (TP) limit. One alternative for meeting this limit is a membrane bioreactor (MBR) process with metal salt addition. Benefits of the MBR process include essentially zero effluent total suspended solids (TSS), reduced footprint, reduced operational complexity, and a high level of pathogen removal. In particular, the removal of all insoluble phosphorus makes this process attractive when faced with a low effluent TP limit. To meet its proposed TP limit, the City of Gainesville, Georgia selected an MBR process with alum addition. A pilot study was conducted to confirm the ability of the process to achieve effluent goals, to verify full-scale design criteria, and to assess solids handling strategies. The results of the study confirm the ability of an MBR process with alum addition to achieve the proposed effluent limits, including 0.13-mg/L TP. Includes 4 references, tables, figures.