Evaluation of dissolved air flotation unit for oil produced water

Abstract

In this investigation a dissolved air flotation system was evaluated. The reactor used was to the lab scale. The Flotation system was used for the treatment of production oil waters, from a separator API located at the Patio Tanks ULE, in Tía Juana Zulia (Venezuela). The samples were characterized by determining parameters such as: pH, chloride, alkalinity, turbidity, suspended solids, oil and grease. The optimum coagulants dosage, and the coagulant to be used were evaluated by the “Jar Test”, using commercial chemical coagulants to help the flotation process in a dissolved air environment. The results showed that, the Cationic Flocculant of High Molecular Weight (FCAPM) was the most appropriated at a concentration of 0,006% in volume (3, 54 mg/L). The flotation tests were carried out at three different pressures (30, 40 and 50 psi), and for each condition the recycle percentage was varied (30 %, 40% and 50% of the feeding). The operational condition in which the best results were obtained were for pressure 40 psi and recycle percentage 40%, at this values the removal of oil and grease was 90%, suspended solids 72% and effluent clarification 70%.

Keywords

• dissolved air flotation (DAF)
• production waters
• oils and grease
• suspended solids