Role of condensate bubbles in enhancing oil droplets and organic acid flotation

Abstract

Poor adhesion of oil droplet-bubble and the inability to manage dissolved organic matter have hindered flotation efficiency. X-ray photoelectron spectroscopy (XPS) was used for this research to describe the surface chemistry of oil droplets. Multi-component condensate droplet vaporization experiments in produced water (PW). PW at different temperatures was used to investigate droplet vaporization behavior, and the interfacial energy theory and vapor boiling theory were employed to explain the vaporization nucleation mechanism. Contact angle, induction time measurements, and flotation analyses were used to assess the surface chemistry of condensate bubbles and the oil removal effect. The results revealed that when multi-component condensate was vaporized in PW at different temperatures, the light components nucleated inside the condensate droplets and generated bubbles enveloped by the condensate film, and the diameter of the bubbles rose as the temperature increased. X-ray photoelectron spectrometry (XPS) investigation showed the existence of hydrophilic oxygen-containing functional groups on the crude oil's surface. The contact angle between the condensate bubbles and the mask oil surface in PW is >150° and spreads faster, while the contact angle between the methane bubbles, the air bubbles and the oil surface are both <90°. The contact angle and the induction time decrease as the organic acid content of the water increases. Condensate bubble flotation has a greater oil removal efficiency than methane bubble and air bubble, which can achieve the extraction and flotation of emulsified oil droplets (83 %) and dissolved acid (63 %).