Desalination & Reuse Handbook - Flipbook - Page 61
FEATURED REUSE PLANTS
TERMINAL ISLAND AWPF, USA.
The ultimate expansion of the Terminal Island Advanced Water
Purification Facility (AWPF) doubled the treatment capacity of
the plant, which injects treated wastewater into the Dominguez
Gap Barrier for agricultural and industrial reuse, and to prevent
saltwater intrusion into the aquifer. The capacity of the AWPF
facility after the expansion is 45,425 m3/d.
Alongside the additional treatment capacity, the expansion added
a Xylem ultraviolet advanced oxidation (UV-AOP) system credited
for 6-log virus and protozoa removal. The UV-AOP system
also achieves NDMA removal and destruction of trace organic
compounds. The enhanced disinfection capacity of the system
creates greater options for other possible end-users, which could
also provide a potential revenue stream for the facility.
A Walsh Group/Carollo Engineers team was formally awarded
the design-build contract for the AWPF in May 2015, with
commissioning in September 2017. The project location on
dredged fill required soil stabilisation to be carried out before
construction and a compact design footprint of 12,000 m2.
Continuous plant operation was maintained throughout the
construction sequence, and the project included a 90-day
shutdown in which the existing AWPF was transitioned onto the
new plant Distributed Control System (DCS) provided as part of
the expansion.
The plant runs tertiary treated effluent water from the Terminal
Island Water Reclamation plant through MF, RO and UV-AOP
disinfection stages. The expansion’s MF system uses 6 Memcor®
CP 240 PVDF ‘N’ series modules manufactured by Evoqua,
followed by a Doosan Hydro (now SafBon Water Technology) twostage, four-train RO system with a 130 PSI operating pressure
and 66% recovery rate. Biofouling is inhibited by maintaining
a 1–3 mg/l chloramine residual in the MF and RO feedwater,
and membranes were selected for their tolerance to this level of
chloramine concentration.
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