Induced gas flotation (IGF) is an efficient physical method for separating dispersed oil from produced water. This study optimized IGF parameters for oils with near-water density (specific gravity ≈ 0.9 g.cm-3) using response surface methodology (RSM). Experiments evaluated flotation time, air-flow rate, salinity, oil concentration, and temperature. Oil-separation efficiency, defined as the percentage ratio of recovered oil mass to the initial oil mass, was measured in a 2 lit glass column equipped with a silicone-membrane bubbler. The RSM model identified flotation time and salinity as dominant factors (p < 0.05). Optimum conditions (45 min, 0.5 L.min⁻¹ air flow, 20 g.lit⁻¹ salinity, 1000 ppm oil, 20 °C) yielded approximately 70 % removal efficiency, with higher temperatures reducing efficiency due to increased oil solubility. The results confirm the applicability of IGF to challenge near-density oil systems and provide an experimentally validated optimization framework.
Bahador et al. (2025) studied this question.