Comparison of drinking water pollutant removal using a nanofiltration pilot plant powered by renewable energy and a conventional treatment facility

In this paper, drinking water pollutant removal between a conventional drinking water treatment and a nanofiltration (NF) pilot plant powered by renewable energy is compared. This kind of plant can be very useful for isolated locations with water quality problems. Energy consumption and related CO2 emissions and the occurrence of synthetic organic compounds in drinking water sources are important environmental and public health issues. NF membranes were used to improve drinking water quality from a holistic point of view. Compared to conventional drinking water treatment, membranes efficiently removed color and turbidity (100%), DOC (93%), ions (97%), and metals and metalloids (ranging from 80% to 100%), but not boron (17%) or pharmaceuticals (Ph's) (varied from 15% to 100%, but still always above conventional treatment). Moreover, NF membranes removed 53% of the trihalomethanes (THMs) present in conventionally treated water. Analyses of 93 persistent organic compounds (VOCs, BTEXs, PAHs, DEs, pesticides…) were carried out, but none of the compounds were detected in the three types of water analyzed (reservoir, conventionally treatment and NF permeate). Reservoir water has a strong hydrophilic composition due to protein-like substances that can promote biofouling. NF membranes effectively removed the hydrophobic fraction (66%).