Treatment of oily wastewater by organic–inorganic composite tubular ultrafiltration (UF) membranes

• Published in: Desalination Vol. 196; no. 1; pp. 76 - 83
• Main Authors: Li, Yu Shui, Yan, Lu, Xiang, Chai Bao, Hong, Liu Jiang
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2006; Elsevier
• Subjects: Applied sciences; Chemical engineering; Exact sciences and technology; General purification processes; Membrane fouling; Membrane separation (reverse osmosis, dialysis...); Oily wastewater; Pollution; Tubular membrane; Ultrafiltration; Wastewaters; Water treatment and pollution; Ultrafiltration; Tubular membrane; Membrane fouling; Oily wastewater; Scanning electron microscopy; Fouling; Permeation; Washing; Solid particle; Surfactant; Retention; Composite material; Waste water; Membrane separation; Chemical oxygen demand; pH; Total organic carbon
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2005.11.021

A tubular UF module equipped with polyvinylidene fluoride membranes modified by inorganic nano-sized alumina particles was used to purify oily wastewater from an oil field. The membrane water permeations of the UF process were analyzed. Retentions of chemical oxygen demand and total organic carbon were more than 90% and 98%, respectively. The results indicate that after UF treatment, oil content was below 1 mg/L, suspended solids content was below 1 mg/L, and solid particle median diameters were less than 2 μm. The quality of the permeation water met the requirement by oilfield injection or drainage. Fouled membranes and washed membranes were analyzed by scanning electron microscopy, and fouled membranes were backwashed with different solutions. Results show that the addition of nanosized alumina particles improved membrane antifouling performance, and the flux recovery ratio of modified membranes reached 100% washing with 1 wt% of OP-10 surfactant solution (pH 10).