Enhancing of Thermal Performance of Solar-Powered Ro Desalination System Using Nanofluids
Abstract
This study investigates the enhancement of heat transfer and energy efficiency in a solar-powered reverse osmosis (RO) desalination system through the use of SiO₂–water nanofluids as the heat transfer medium. Using concentrations ranging from 0.5% to 3% by volume, SiO₂–water nanofluids were produced with nanoparticle sizes of 12–16 nm. Heat transfer efficiency at 1% concentration showed up to a 22% improvement over conventional water by experimental testing under flow rates of 10–20 L/h and solar irradiation levels from 500 to 1000 W/m². More stable feedwater temperatures within the ideal membrane operating range of 25–30 °C made possible by this improvement helped lower water viscosity by 35%, lower pumping power, and boost permeate output. From 06:00 to 18:30, thermal energy from both water and nanofluids was either sufficient or exceeded according to hourly simulation results. However, lacking solar input, the system failed to satisfy the thermal demand following sunset (19:00–23:00). The collector thermal efficiency increased by up to 22% at 1% nanofluid concentration, with outlet temperature rising by 12–15°C compared to water. Integration of heat accumulators highlights the importance of use of accumulators such kind thermal systems. These findings demonstrate the potential of nanofluid-assisted solar desalination systems for sustainable freshwater production in arid regions.
Keywords
solar desalination system, reverse osmosis, nanofluids, solar thermal collectors, nanofluid