Application of Hydrocyclone Combined with Electrocoagulation as Pretreatment to Improve the Quality of Seawater Intake in Desalination

This research presents a pioneering approach that combines hydrocyclones with electrocoagulation (EC) to improve desalination pretreatment processes. The study integrates hydrocyclones' centrifugal force for particle separation with EC’s ability to destabilize and aggregate suspended solids, reducing fouling in RO systems without chemical additives. Seawater samples from the Al-Khobar coastline in the Eastern Region of Saudi Arabia were analyzed for particle size distribution, salinity, and viscosity, which guided the experimental design. Electrocoagulation experiments demonstrated that using aluminum/graphite electrodes effectively enlarged salt particle size from 0.81 nm to 2.96 µm, making them more suitable for hydrocyclone capture. Computational fluid dynamics (CFD) simulations were validated against published experimental data to optimize hydrocyclone design following EC experiments. Three industrial-scale hydrocyclones were analyzed using validated CFD simulation settings, with results showing removal efficiencies of 59%, 70%, and 41% for 3 µm particles in hydrocyclones H₁, H₂, and H₃, respectively. The integrated EC-hydrocyclone system effectively enhanced particle removal, which can reduce fouling potential and improve water quality for RO processes. The proposed approach can also reduce chemical usage in desalination processes, improving sustainability and environmental performance and significantly advancing the transition toward a circular economy and eco-friendly desalination practices.