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43 revealingaveragenitrate recovery exceeding 80%. The hybrid IX system presented a robust brine reuse without compromising nitrate removal efficiency, with thepotential for nitrogen recovery from the system. Moreover, the nitrate brine treatment systemoffers thepotential for extended application in recovering nitrate fromnitric acid waste in themetal processing sector, and nitrate brines originating from the fertilizer industry. מפעל טיפול במי לגונה בחוף השנהב Aghien Boaz Keinan Fluence water The Ivory Coast Water Treatment Plant (WTP), designed and constructed by Fluence, supplies 150,000 m 3 /day of potable water to the city of Abidjan. The plant abstracts raw water from the Aghien Lagoon, treats it to World Health Organization (WHO) standards, and delivers it through the municipal distribution system. A key challenge of the Aghien Lagoon is the seasonal proliferation of cyanobacteria (blue- green algae), which can release toxins harmful to human health. To address this, theWTP employs a multi-barrier treatment process that ensures robust performance across varying raw water conditions. The treatment sequence begins at an offshore intakepontoon, located1.2kmfromthe shoreline, where water is screened and pumped to the WTP. Pretreatment with coagulant, flocculant, and acid is followed by dissolved air flotation (DAF), remineralization, multimedia filtration, ozonation, and biological activated carbon (BAC) filtration. Final disinfection with chlorine ensuresmicrobiological safety. The treatedwater is adjusted for pH and mineral balance before distribution to Abidjan. Residuals from treatment are thickened, dewatered, sterilized, and safely disposed of, with clarified effluent returned to the lagoon in compliance with local regulations. This integrated treatment solution provides a secure, reliable, and high-quality drinking water supply for Abidjan, safeguarding public health and supporting the city׳s growing demand. NITRATE BRINE TREATMENT FOR EFFICIENT NITRATE REMOVAL IN WATER TREATMENT Rotem Sade Natural water contamination by nitrate (NO3-) is a global concern caused by agricultural fertilizer use, posing health risks likemethemoglobinemia and cancer. Regulatory standards limit nitrate concentrations indrinkingwater to50mg/l (WHO) and 44 mg/l (EPA). Many regions worldwide exhibits nitrate concentration above these limits, leading to the development of nitrate removal techniques, with ion exchange (IX) being the most prevalent. However, IX׳s brine disposal is costly, prompting the exploration of brine reuse in IX hybrid systems. In this study, we used a small-scale IX column coupled to a Nitrate Brine Treatment (NBT) unit to assess the feasibility of reusing regenerated brine without compromising nitrate removal efficiency in the IX and to study the recovery of the removed nitrate as nitric acid. The hybrid setup consistedof a 30 gallons per hour IX system coupled with an NBT unit. Within the NBT unit, a selective process eliminated the nitrate from the brine by converting it into NOx using a thermal reactor filledwith activated carbon. The hybrid IX system treated city water spiked with nitrate (100 mg/l) over 42 regeneration cycles. Nitrate breakthrough behavior was typical, with concentrations maintained below 10 mg/l for 300-350 bed volumes before the breakthrough. No degradation in nitrate removal efficiency was observed, affirming the potential for brine reuse. The nitrate reduction rate was measured at 1.88 g of removed nitrate per hour per kg of activated carbon. This rate suggested a reactor size comparable to the volume of the IX system, emphasizing the need to optimize reaction rates for practical application. Nitrate recovery was evaluated by subjecting a synthetic brine containing nitrate levels between 20-30 g/l and chloride concentrations ranging from 40-70 g/l to treatment with the NBT unit. The NBT unit consistently reduced nitrate concentrations to below 4 g/l in the brine, meeting the target for brine reuse. Furthermore, nitrogen recovery was evaluated by introducing the NOx emitted from the reactor to a set of acid and alkaline traps,