Preparation and evaluation of double‐hydrophilic diblock copolymer as viscosity reducers for heavy oil

Abstract

In this work, a series of double-hydrophilic diblock copolymers of N-acryloylmorpholine (NAMO) and N,N-dialkylacrylamide are prepared as the additives for viscosity reduction, which could effectively interact with the asphaltenes and resins. The viscosity reduction effects of the types of N,Ndialkylacrylamide monomer (N,N-dimethyl acrylamide & N,N-diethyl acrylamide) and degree of polymerization (DP) of poly(N,N-dialkylacrylamide) block in copolymers on heavy oil are tested with heavy oils with different viscosities.These viscosity reducers can work with small dosages (>25 mg L À1 ). The interfacial tension between oil and water is significantly weakened, and the aggregating structures of asphaltenes and resins are disassembled into smaller aggregates and covered with polymers with the addition of copolymers. The re-establishment of aggregates among polar components seems to be prevented, and the stability of the heavy oil/water emulsions is greatly enhanced as a result. All these results provide the prerequisites for water-soluble diblock copolymers working as viscosity reducers for various heavy oils.

Preparation and Performance Evaluation of Amphiphilic Polymers for Enhanced Heavy Oil Recovery

“…The peak nea ppm corresponds to the H of the amino group (-NH2) on acrylamide. The peak a ppm corresponds to the H of the benzene ring on benzyl acrylate [32,33]. The resul tained from IR and 1 H-NMR confirm the successful synthesis of the intended produ…”

Foam Systems for Enhancing Heavy Oil Recovery by Double Improving Mobility Ratio

“…As shown in Figure 7b, without a foaming agent, the water/oil mobility ratio at 1.47 m/d linear velocity was as high as 116. 33. With the increasing foaming agent concentration for both XHY-4 and KX-048, the water/oil mobility ratio gradually decreased.…”

“…For example, recent studies also proved that the inhibition of asphaltene precipitation is also an important method for improving heavy oil recovery [32]. Moreover, surfactants are often injected into heavy oil to form emulsions or foams to improve mobility [26,[33][34][35]. Emulsions are generally realized by adding surfactants, which could decrease the interface tension between the water phase and oil phase into heavy oil.…”

Poly(octadecyl methacrylate) via RAFT Technique and Its Rheological Study for Waxy Crude

“…This results in the change in various characteristics of crude oil which includes viscosity, pour point, and yield stress. The formation of extended crystal networks further exacerbates these issues, causing flow difficulties and requiring additional measures to ensure smooth transportation. − In addressing this issue, various techniques have been devised, such as heating, light oil dilution, emulsion, and magnetic field processing, all of which aim to enhance the low-temperature flow characteristics of waxy crude oils. − Each of the above methods possesses some major drawbacks and also presents some undesired challenges which include consumption of high energy, higher operational cost, adapting solutions to diverse geological conditions, and post processing difficulties. In the recent decades, addition of polymeric PPD/FI to crude oil has proved to be one of the most effective methods to inhibit wax precipitation and improve the flow ability of waxy crude oil, thus reducing the cost of pipeline transportation.…”