《纳米材料如何应用于润湿性变换》由会员分享,可在线阅读,更多相关《纳米材料如何应用于润湿性变换(8页珍藏版)》请在金锄头文库上搜索。
1、原文;链接:JPT 2015 年 12 月 P74-75摘要:文章回顾了改变岩心润湿性的几类方法,概括性介绍了用于润湿性改变纳米材料的分类、作用方式、流体载体和存在的问题。A Study of Wettability-Alteration Methods With Nanomaterials Application纳米材料如何应用于润湿性变换The use of nanomaterials for alteration of wettability is a method that has grown in prominence after the development of techniq
2、ues for synthesizing nanosized particles in the late 1980s. In this paper, after a review of the fundamentals of wettability alteration, a discussion of nanomaterials used for wettability alteration is provided. Among these nanomaterials, nanoparticles of silica and polysilicone indicate better resu
3、lts in terms of efficiency on incremental oil recovery in waterflooding. 纳米尺度的粒子合成技术在 1980 年代末发展后,使用纳米材料改变润湿性的方法也已取得突出进展。本文在介绍润湿性改变的基本原理之后,讨论纳米材料是如何用于润湿性改变的。众多纳米材料之中,纳米二氧化硅和有机硅聚合物在帮助提高水驱采收率上有着更好的作用效果。Introduction介绍Wettability is the tendency of a fluid to spread over a specific surface and is relati
4、ve to other existent fluids in that system and is defined by the contact angle of a droplet of the fluid and the surface. It is a result of adhesion forces between the fluid and the minerals of the rock. The wettability of a rock ranges from strongly water-wet to strongly oil-wet and is a result of
5、brine/oil/rock interactions in a reservoir. There are different types of rocks on the basis of these interactions and wettabilities: 润湿性是一种流体相对于其他存在的流体系统分布在特定表面一个趋势。可由液体的液滴与表面的接触角作为定义。这是流体和岩石矿物之间的粘附力作用的结果。岩石的润湿性范围从强烈亲水到强烈亲油,并且是由于盐水/石油/ 储层岩石相互作用而成的。在这些交互作用和润湿性基础上,有多种不同类型的岩石。1. If no, or equal, tenden
6、cy is shown from oil or brine to spread over the surface of the rock, the system is said to have neutral wettability or intermediate wettability. 1如果从石油或盐水在岩石表面传播趋势没有或者显示相同的情况下,这个系统可称为中等润湿或中间润湿性。2. Because different mineralogies coexist in an oil reservoir, different wettabilities are also expected.
7、 If this variety in the reservoir is not negligible, then, in different parts of the reservoir, different chemical interactions between fluids and rocks are observed and, consequently, some areas of the reservoir indicate strongly water-wet behavior whereas some other areas indicate strongly oil-wet
8、 behavior. This heterogeneous wettability behavior is known as fractional wettability. 2由于不同的矿物在同一油藏中共存,所以不同的润湿性是也是如此。如果这种多样化润湿性在油藏中不可忽略,那么,在油藏的不同部位,可观察到流体和岩石之间的不同的化学作用。因此,一些区域的储层出现强亲水特征,而其他区域则表现为强亲油。这种非均匀润湿行为称为部分润湿性。3. In some cases, the smaller pores are occupied by water and can be considered wat
9、er-wet, while larger pores are captured by oil. This type of wettability distribution is known as mixed wettability, in which the residual oil saturation is low because the oil is displaced more easily from larger pores. 3在某些情况下,较小的孔隙被水填满,可以被认为是亲水的,而更大的毛孔被石油占据。这种类型的润湿性分布称为混合润湿,一般这种类型的油藏残余油饱和度较低,因为石油
10、更容易从大孔隙中被驱出。The solid/fluid and fluid/fluid surface energies are governed by the chemical compositions of the fluid and rock. In other words, the mineralogy of a rock and chemical properties of the fluid influence the relative adhesive tensions and, consequently, wettability. 固体/液体和液体/液体表面能量是由流体和岩石的
11、化学成分决定的。换句话说,岩石矿物组成和流体的化学性质影响相对粘附张力,进而影响润湿性。The most common methods for wettability measurements, discussed in detail in the complete paper, include the following: 最常见的润湿性测量方法在完整的论文里做了详细讨论,包括:1. Amott wettability index 1。Amott 润湿指数2. US Bureau of Mines (USBM ) wettability index 2。美国矿山局(USBM)润湿性指数3.
12、Combined Amott-USBM wettability test 3结合 Amott-USBM 润湿性测试4. Contact-angle methods 4接触角法Because any clean rock exhibits water-wetting behavior, it is believed that all petroleum reservoirs were initially water-wet. This water was later displaced by oil because of migration, and sometimes there is a s
13、hift to relatively oil-wet compared with the initial wetting tendency. Some polar components of oil then act as surfactants and penetrate through the thin film of water on the pore surfaces and adsorb strongly on the rock. 因为任何洁净的岩石都表现出亲水行为,因为可以判断所有油藏最初都是水湿的。水后来被运移进来的油所替代,有时会有一个从初始的水湿转向相对亲油的倾向。一些石油极
14、性组分随后起到表面活性剂的作用,穿透薄膜孔隙水然后强烈的吸附在岩石表面上。On the basis of the component minerals, some rocks have water-wetting or oilwetting natures. In a water-wet medium, water captures the small pores and also coats the surface of the larger pores while oil filaments are in the larger pores on the mentioned water su
15、rface. The water relative permeability in larger pores is small both before coreflooding (because presence of oil prohibits water mobility) and after coreflooding (because the residual oil saturation impedes water relative permeability). 基于矿物的组分构成,一些岩石有亲水或亲油性质。在亲水介质中,水占据小孔隙并且覆盖大孔隙的表面,而油则是在大孔隙中,并与上述水
16、表面直接接触。大孔隙中的水相对渗透率小,无论是在水驱之前(因为存在的油禁止水流动)还是水驱之后(因为残余油饱和度阻碍水相对渗透率) 。In an oil-wet system, the positions of the fluids are reversed, and during waterflooding, the water relative permeability in larger pores increases and impedes the oil movement faster than in a water-wet system. In other words, an oil-wet system is not a good candidate for waterflooding compared with a water-wet system because more oil would reside in an oil-wet system after water breakthrough