Marine Macro Algae as a Sustainable Solution for Refinery Wastewater Treatment in Oman

Abstract

Industrial wastewater management, particularly in the petroleum refining sector, is a pressing environmental challenge due to complex pollutants, including hydrocarbons, heavy metals, and sulfides. This research explores the potential of marine algae as biosorbents for treating industrial wastewater through batch and column studies. Two marine algae species - brown seaweed Sargassum Ilicifolium and green Ulva lactuca were utilized to assess their potential for removing organics, phenol, and lead from synthetic and refinery wastewater. The study's objectives included characterizing petroleum industry effluent, selecting suitable algae from three different regions in Oman (Seeb, Sohar, and Salalah), and analyzing algae properties using advanced characterization tools like Scanning Electron Microscopy (SEM), X-Ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). A batch experimental study demonstrated removal efficiencies of up to 85% for phenol and 92% for lead using Sargassum ilicifolium, and up to 78% for phenol and 88% for lead using Ulva lactuca. Column studies examined the effectiveness of Ulva lactuca in reducing major wastewater pollutants, achieving reductions of 76% in Chemical Oxygen Demand (COD), 82% in Total Suspended Solids (TSS), 70% in Total Dissolved Solids (TDS), and 85% in turbidity. Refinery wastewater treatment using Sargassum ilicifolium achieved a maximum removal efficiency of 80% for Chemical Oxygen Demand (COD), while Ulva lactuca demonstrated performance of up to 90% in removing organic pollutants. Packed columns combining Ulva lactuca with activated carbon enhanced pollutant removal rates. The findings demonstrate the potential of Sargassum ilicifolium and Ulva lactuca as alternative biosorbents for refinery wastewater treatment. This study also demonstrates the potential for integrating algae-based treatment systems into existing wastewater treatment processes, while further economic and environmental assessments are required to establish their feasibility and sustainability for full-scale industrial application.