The Role of Nanoparticles in Enhanced Oil Recovery (EOR)

提高采收率（EOR）是指向油藏中注入含有可能添加剂的水/气以开采更多石油。EOR通常针对的是水驱或气驱后的剩余油，即油田开始产生过多的水/气和石油产量下降后的剩余油。有效的提高采收率方法既针对孔隙尺度的采收率，也针对大型油田（垂直和面积）的波及效率。提高采收率方法的选择和效果取决于原油和储层岩石的性质。本研究的目标是优化纳米颗粒强化水驱技术，以纽芬兰海上油田为例进行常规采油。这项工作对加拿大传统石油的可持续和增产以及我们的资源型经济至关重要。***实验室研究表明，纳米颗粒增强水驱（一种化学提高采收率）可能是有效的，因为纳米颗粒可以改变水和剩余油之间的界面张力，纳米颗粒可以改变岩石的润湿性（接触角）。其中一个挑战是在储层条件下，在盐水（不同盐度）中形成稳定的纳米颗粒水溶液。纳米颗粒也可以吸附在岩石表面。这可能会产生积极或消极的影响，这取决于岩石的润湿性是否得到了有利的改变。此外，如果纳米颗粒优先吸附在岩石上，它们可能无法降低水和油之间的界面张力。***本研究将系统地研究在油藏条件下使用不同的市售纳米颗粒提高采收率。我们将研究纳米颗粒-盐水溶液在一系列油藏条件下的稳定性。纳米颗粒增强盐水和油的界面张力作为纳米颗粒类型、浓度、水盐度、油成分、温度和压力的函数将使用垂滴法确定。我们将根据矿物学和纳米颗粒类型来研究润湿性（接触角）作为纳米颗粒吸附在岩石上的函数。在描述了流体-流体和流体-岩石性质之后，我们将使用两种类型的实验室规模油藏（微模型和岩心），根据不同质量（20-35oAPI）常规油的流体性质（水的盐度、纳米颗粒的类型和浓度、注入速度和体积）和油藏性质（孔径分布、渗透率和矿物学）来研究和优化纳米颗粒增强水驱。***通过这项研究，我们将以纽芬兰海上油田为例，筛选和优化纳米颗粒增强水驱的实际和一般现场应用（砂岩油藏的常规油）。**

Enhanced oil recovery (EOR) refers to the injection of water/gas with possible additives into a petroleum reservoir to produce more oil. EOR typically targets post waterflood or gas flood residual oil after the field starts producing too much water/gas and oil production decreases. Effective EOR methods target both pore scale recovery as well as large scale field (vertical and areal) sweep efficiency. The choice and effectiveness of EOR methods depend on the oil and reservoir rock properties. The goal of this research is to optimise nanoparticle enhanced waterflooding for conventional oil recovery using the offshore Newfoundland oil fields as case studies. This work is important to the sustainable and increased production of Canada's conventional oil and our resource based economy.***Laboratory research has shown that nanoparticle enhanced waterflooding, a type of chemical EOR, may be effective because the nanoparticles may alter the interfacial tension between the water and residual oil, and the nanoparticles may alter the wettability (contact angle) of the rock. One challenge is forming a stable nanoparticle-water solution in brine water (varying salinity) at reservoir conditions. Nanoparticles may also adsorb to the rock surface. This may have a positive or negative impact depending on whether wettability of the rock is changed favourably. Also, if the nanoparticles preferentially adsorb to the rock, they may not be available to decrease the interfacial tension between the water and oil.***This research will systematically examine the use of different commercially available nanoparticles for EOR at reservoir conditions. We will investigate the stability of the nanoparticle-brine solutions over a range of reservoir conditions. The interfacial tension of the nanoparticle enhanced brine and oil as a function of nanoparticle type, concentration, water salinity, and oil composition, temperature, and pressure will be determined using the pendant drop method. We will examine the wettability (contact angle) as a function of nanoparticle adsorption on the rock based on the mineralogy and nanoparticle type. Having characterised the fluid-fluid and fluid-rock properties, we will use two types of laboratory scale reservoirs (micromodels and cores) to investigate and optimise nanoparticle enhanced waterflooding based on the fluid properties (salinity of the water, type and concentration of nanoparticles, injection rate, and volume) and reservoir properties (pore size distribution, permeability, and mineralogy) on the recovery of different quality (20-35oAPI) conventional oils.***Through this research, we will screen and optimise nanoparticle enhanced waterflooding for practical and general field application (conventional oil in sandstone reservoirs) using offshore Newfoundland field conditions as a case study. **