Abstract

As a byproduct of the crude oil industry, oily water is a major environmental concern. In this study, a novel methodology that used low-frequency ultrasound (US) for the removal of oil from the production of oily water was proposed. A continuous phase was prepared by dissolving NaCl (18 g·L⁻¹), CaCl₂ (6 g·L⁻¹), and MgCl₂ (3 g·L⁻¹) in water. Synthetic oil-in-water emulsion was without adding artificial emulsifiers (oil contents: 495–687 mg·dm⁻³) with median droplet size distributions of approximately 10 µm was prepared using a Brazilian heavy crude oil (API gravity of 11.9). Experiments were performed using ultrasonic baths operating at 35, 45, and 130 kHz at 60 °C in the presence of glass Raschig rings without any addition of chemical demulsifiers. Other materials were also evaluated: PVC; PTFE; Polypropylene; steel; and copper. For the synthetic oil-in-water emulsion with 495 mg·dm⁻³ oil, in the presence of glass Raschig rings, an oil removal efficiency of approximately 76.4% (35 kHz, 20 min) was achieved. Higher removal efficiencies were obtained for synthetic oil-in-water with 495 mg·dm⁻³ oil than for those with 687 mg·dm⁻³ oil (50.1%, 130 kHz, 20 min). Although typically used for emulsification, these findings reveal that low-frequency US association of glass Raschig rings is also a promising technology for treating the produced water to remove oil.

摘要

作为原油工业的副产品，含油水是一个主要的环境问题。在这项研究中，提出了一种使用低频超声 (US) 从含油水生产中去除油的新方法。通过将NaCl (18 g·L ^-1 )、CaCl ₂ (6 g·L ^-1 )和MgCl ₂ (3 g·L ^-1 )溶解在水中来制备连续相。合成水包油乳液不添加人工乳化剂（含油量：495-687 mg·dm ^-3) 使用巴西重质原油（API 比重为 11.9）制备了大约 10 µm 的中值液滴尺寸分布。使用在 35、45 和 130 kHz、60 °C 和玻璃拉西环存在下运行的超声波浴进行实验，不添加任何化学破乳剂。还评估了其他材料：PVC；聚四氟乙烯；聚丙烯; 钢; 和铜。对于含 495 mg·dm ^-3油的合成水包油乳液，在玻璃拉西环的存在下，除油效率约为 76.4%（35 kHz，20 分钟）。使用 495 mg·dm ^-3油的合成水包油比使用 687 mg·dm ^{-3 的}合成水包油获得更高的去除效率油（50.1%，130 kHz，20 分钟）。虽然通常用于乳化，但这些发现表明，低频美国玻璃拉西环协会也是一种处理采出水以去除油的有前途的技术。