AWWA MTC69724

The Gibson Island Advanced Water Treatment Plant (GIAWTP) applies state of the art technology to treat domestic wastewater using sand ballasted clarification, microfiltration, reverse osmosis, and advanced oxidation disinfection. The product water is used for direct industrial reuse (potable substitution) and indirect potable reuse via existing reservoirs. This plant is unique from the other two plants in the Western Corridor Recycled Water Program in that it has the most restrictive footprint and utilized sand ballasted clarification (Actiflo) and has two sources of secondary effluent: Luggage Point Wastewater Treatment Plant (WWTP), one of the other AWTPs; and, Gibson Island Advanced Water Treatment Plant (GIAWTP). GIAWTP has conducted a series of bench and pilot-scale tests over a two-year period which included: microfiltration (MF) performance with and without sand-ballasted flocculation; reverse osmosis (RO) element comparison; polymer evaluation; N-Nitrosodimethylamine (NDMA) formation; and, full-scale demonstration tests. This paper presents results from two major efforts, the RO nitrogen removal performance and NDMA formation tests, as well as comparisons of these bench/pilot-scale results to fullscale performance. Includes 12 references, tables, figures.