Combined micromixing and coalescence separation for improved oil desulfurization

Abstract

In petroleum, mercaptan impurities generate malodorous fumes that pose risks to both human health and the environment, and leading to substandard oil quality. Lye desulfurization is a widely employed technique for eliminating mercaptans from oil. In traditional scrubber towers, lye and oil are poorly mixed, the desulfurization efficiency is low, and the lye consumption is high. To enhance washing efficiency, a droplet micromixer and corresponding fiber coalescence separator were developed. By optimizing the structure and operating parameters, more effective mixing and separation were achieved, and both caustic washing and desulfurization were enhanced. The proposed mixer/separator outperforms the industry standard by reducing the caustic loading by 30% and offers superior economic and engineering performances. The results of this study offer a direction for designing and optimizing a mercaptan removal unit to enhance the scrubbing effectiveness and decrease expenses to achieve more efficient and green production process.