Miniaturized surface-plasmon-resonance sensor for rapid on-site detection of wax deposition in oil wells

原油中含有蜡，在储层条件下可溶于油液相。然而，当原油温度下降时，蜡在液体中的溶解性降低，溶解的蜡分子倾向于结晶并形成固体颗粒。蜡沉积是石油生产、运输和加工过程中的一个主要问题，会导致采收率降低、管道和井眼堵塞以及设备损坏等并发症。Chau博士将与斯伦贝谢加拿大有限公司合作开发一种紧凑、坚固的光学传感器，可在现场的流线和井眼条件下使用，直接量化蜡沉积的开始和行为。该传感器将基于一种表面敏感现象，即表面等离子体共振（SPR）。表面等离子体共振描述了一种情况，在这种情况下，入射到高导电性金属薄膜上的光激发了粘在金属表面的共振电荷振荡。这些振荡对金属表面附近环境的扰动高度敏感。该项目将探索新的SPR传感器设计，能够检测由于蜡沉积引起的介电扰动，同时保护金属表面免受石油的腐蚀影响。该传感器最初将在UBC的Chau博士应用电磁学实验室实施和测试，使用DBR技术中心提供的纯组件样品和死油（大气压）样品。如果这些测试成功，SPR传感器将在DBR技术中心的专用室中进行测试，该室可以达到流管或井筒条件下的高压和高温。因此，该项目将为检测蜡沉淀和沉积的新光学技术提供概念验证数据。该项目的成功将为UBC和斯伦贝谢未来的合作铺平道路，以进一步开发和商业化用于流动保证的SPR传感器技术。

Crude oils contain waxes that are soluble in the oil liquid phase at reservoir conditions. However, when the crude oil temperature drops, the waxes become less soluble in the liquid and dissolved wax molecules tend to crystallize and form solid particles. The deposition of wax is a major problem during oil production, transportation, and processing, causing complications such as reduced extraction, clogging of pipelines and well-bores, and equipment damage. Dr. Chau will collaborate with Schlumberger Canada Ltd. to develop a compact, robust, optical sensor that can be used on-site at flow line and well bore conditions to directly quantify the onset and behaviour of wax deposition. The sensor will be based on a surface-sensitive phenomenon known as surface plasmon resonance, or SPR. Surface plasmon resonance describes a condition in which light incident onto a highly conductive metallic film excites resonant charge oscillations that are stuck on the surface of the metal. These oscillations are highly sensitive to perturbations in the environment adjacent to the metal surface. The project will explore new SPR sensor designs that are capable of detecting dielectric perturbations due to wax deposition, while protecting the metallic surface from corrosive effects of oil. The sensor will be initially implemented and tested in Dr. Chau's Applied Electromagnetics Laboratory at UBC, using pure component samples and dead oil (atmospheric pressure) samples supplied by DBR Technology Center. If these tests are successful, the SPR sensor will be tested at the DBR Technology Center inside specialized chambers that can reach high pressures and temperatures typical of flow-line or well-bore conditions. Thus, this project will provide proof-of-concept data on a new optical technique for detecting wax precipitation and deposition. The success of this project will pave the way for future collaborations between UBC and Schlumberger to further develop and commercialize SPR sensor technologies for flow assurance.