Barcelona, three years of experience in brackish water desalination using EDR to improve quality. New O&M procedures to reduce low-value work and increase productivity

Abstract The 4.5 million inhabitants of Barcelona and the surrounding area are mainly supplied with surface water from the Llobregat and Ter river basins. The Llobregat river water shows important concentrations of parameters associated with salinity (Na+, K+, Cl−, and Br−), due to both natural and anthropogenic processes. Furthermore, many problems are associated with the increase in micropollutant and microbiological levels due to both urban and industrial sewage. These problems produce many interruptions of the process, some of them lasting many hours. As a consequence, the high levels of bromide (ranging between 0.5 and 1.2 mg/L), natural organic matter and temperature (T) produce high concentrations of trihalomethanes (THMs) after chlorination, showing a high brominated profile. To minimize the THMs problem, in 2009, the water utility Aigues Ter-Llobregat (ATLL) introduced a new technology based on a membrane process in the Llobregat-Abrera Drinking Water Treatment Plant (DWTP): a new Electrodialysis...