Achieving the Super Gas-Wetting Alteration by Functionalized Nano-Silica for Improving Fluid Flowing Capacity in Gas Condensate Reservoirs

Abstract

It is well-known that the production of gas-condensate reservoirs is significantly affected by the liquid condensation near the wellbore region. Gas-wetting alteration can be one of the most effective approaches to alleviate condensate accumulation and improve liquid distribution. However, gas well deliverability is still limited because the wettability of cores is altered only from liquid-wetting to intermediate gas-wetting by using traditional chemical stimulation. To solve this bottleneck problem, herein, we developed a fluorine-functionalized nanosilica to achieve super gas-wetting alteration, increasing the contact angles of water and n-hexadecane on the treated core surface from 23 and 0° to 157 and 145°, respectively. The surface free energy reduces rapidly from 67.97 to 0.23 mN/m. The super gas-wetting adsorption layer on the core surface formed by functionalized nanosilica not only increases the surface roughness but also reduces the surface free energy. The core flooding confirms that the required pressure for displacement is apparently reduced. Meanwhile, the core permeability can be dramatically restored after the super gas-wetting alteration. The microscopic visualization is employed to further understand the impact of fluorine-functionalized nanosilica on the fluid flow behavior and mechanism in porous media. The oil saturation in the micromodel decreases sharply from 48.75 to 7.84%, eliminating the “water locking effect” and “Jiamin effect”, which indicates that the added functional nanosilica effectively improves fluid flow capacity and may contribute to production in the gas condensate reservoirs. In addition, this work reveals the fluid flow behavior and mechanism in the reservoir in detail, which will expand the better application of this material to many oilfields and other mining engineering systems.

Effects of modified carbon nanotubes with different sizes on properties of epoxy shape memory polymers

“…The surface modification of MWCNTs has been described by previous papers in detail 17‐19 . The absorption peaks of OH stretch (carboxylic acids) and CO stretch appeared at 2923 and 1739 cm −1 for CNT‐COOH, while no obvious characteristic peaks were observed in IR curve for CNT 20‐21 . This indicates that the carboxyl group has been successfully grafted onto pure CNT after acidation modification.…”

Effects of networks composed of epoxy/dual thiol‐curing agents on properties of shape memory polymers

“…On the former, lots of researches have been done to study the effect of different types of matrix or curing agents on the properties of SMPs. It was confirmed that molecular types do have important impact on performance of SMPs, and SMPs with excellent properties have been prepared and systematically studied 10 . For instance, the rigid structure containing benzene ring could be introduced to enhance mechanical strength of polymers, 11 or amine based curing agents with long aliphatic chains could be added to improve toughness 12 .…”

Corrosion Inhibition Coating Based on the Self-Assembled Polydopamine Films and Its Anti-Corrosion Properties

“…Thus, the anti-corrosion of wellbore, pipelines and related facilities is a continuous task [3][4][5][6][7]. Most oil and gas wellbore and pipeline corrosion inhibitors need to be continuously injected into the fluid for corrosion inhibition, which requires additional work on the part of on-site operators [8][9][10]. One attractive anti-corrosion strategy is to modify the surfaces of wellbore and pipeline to make them have stable corrosion resistance during the production, while reducing the workload.…”