The Role of Nanoparticles in Enhanced Oil Recovery (EOR)

提高采收率(EOR)是指将含有可能添加剂的水/气注入到油藏中以生产更多的石油。提高采收率通常针对水驱或气驱后的剩余油，因为油田开始生产过多的水/气，石油产量下降。有效的提高采收率方法的目标既包括孔隙规模的恢复，也包括大范围的现场(垂直和平面)波及效率。提高采收率方法的选择和效果取决于原油和储集岩的性质。这项研究的目标是以纽芬兰近海油田为例，优化纳米颗粒强化注水开采技术，用于常规采油。这项工作对加拿大常规石油的可持续增产和我们以资源为基础的经济非常重要。 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，因为纳米颗粒可能会改变水和残余油之间的界面张力，并且纳米颗粒可能会改变岩石的润湿性(接触角)。一个挑战是在水库条件下，在盐水(不同盐度)中形成稳定的纳米颗粒-水溶液。纳米颗粒也可能吸附在岩石表面。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发生了有利的变化。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。 这项研究将系统地研究在油藏条件下使用不同的商业可获得的纳米颗粒来提高采收率。我们将研究纳米颗粒-盐水溶液在一系列储藏条件下的稳定性。纳米颗粒增强盐水和原油的界面张力随纳米颗粒类型、浓度、水的盐度以及油的组成、温度和压力的变化将使用悬滴法进行测定。我们将根据矿物学和纳米颗粒的类型来研究润湿性(接触角)作为纳米颗粒在岩石上吸附的函数。在表征了流体-流体和流体-岩石性质之后，我们将使用两种实验室规模的油藏(微型模型和岩心)来研究和优化纳米颗粒增强注水驱，其基础是不同质量(20-35oAPI)常规油的流体性质(水的矿化度、纳米颗粒的类型和浓度、注入速度和体积)和储层性质(孔隙大小分布、渗透率和矿物学)。 通过这项研究，我们将以纽芬兰近海油田条件为例，筛选和优化纳米颗粒强化注水，以用于实际和一般的现场应用(砂岩油藏中的常规石油)。

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.