Research progress of water-soluble polymer viscosity reducer

doi:10.11949/0438-1157.20250333

Abstract

Abstract:

The high viscosity and low mobility of heavy oil are the technical bottlenecks restricting its recovery. Water-soluble polymer viscosity reducers, with their unique synergistic mechanism of reducing oil viscosity and increasing water viscosity, provide a promising chemical flooding approach to address this problem. This article reviews the mechanism of action of water-soluble polymer-based heavy oil viscosity reducers and explores the progress in molecular design of polymer-based viscosity reducers. It focuses on dissecting the progress of polymer structures from conventional long-chain alkyl and aromatic monomers to stimuli-responsive monomers. The viscosity reduction effect and mechanism of different types of polymer-type viscosity reducers are analyzed. Although existing polymer-based viscosity reducers have demonstrated notable success in lowering heavy oil viscosity, they still face challenges, including unclear transport behavior in porous media, difficulty in demulsification, and concerns regarding economic feasibility.

Key words: conventional heavy oil, water-soluble viscosity reducer, polymer, emulsion, viscosity

摘要：

稠油的高黏度与低流动性是制约其开采的技术瓶颈。水溶性聚合物型降黏剂凭借其对油相降黏与水相增黏的独特双效协同机制，为解决此难题提供了极具前景的化学驱途径。综述了水溶性聚合物型稠油降黏剂的作用机理，探讨了聚合物型降黏剂的分子设计进展。从常规的长链烷基类单体、芳香族单体到响应型单体，研究了这些单体在水溶性聚合物型降黏剂中的应用，并分析了不同类型聚合物型降黏剂的降黏效果及机理。尽管现有的聚合物降黏剂在降低稠油黏度方面取得了显著成效，但仍面临多孔介质中规律不清晰、乳状液破乳难以及经济性等挑战。

关键词: 普通稠油, 水溶性降黏剂, 聚合物, 乳液, 黏度

CLC Number:

TE 39

Fumin ZHANG, Yefei WANG, Hongbo WANG, Mingchen DING, Wuhua CHEN, Jian LIAO, Jianbin LIU, Zhixue HUANG. Research progress of water-soluble polymer viscosity reducer[J]. CIESC Journal, 2025, 76(12): 6121-6133.

张富民, 王业飞, 王红波, 丁名臣, 陈五花, 廖健, 刘建斌, 黄志学. 水溶性聚合物型稠油降黏剂研究进展[J]. 化工学报, 2025, 76(12): 6121-6133.

Figures/Tables 8

Fig.1 Mechanism of action of long-chain alkyl monomer-related polymer viscosity reducers in heavy oil[30-33]

Table 1 Commonly used long-chain alkyl monomers for polymer viscosity reducers

单体名称	优点	缺点	文献
2-丙烯酰胺基十二烷基磺酸钠	注入0.2PV的1500 mg/L的两亲聚合物提高采收率27%	界面张力较高	[41]
十六烷基二甲基烯丙基氯化铵	对稠油的降黏率超过95%，能使稠油采收率提高17.9%	合成复杂，成本昂贵	[19]
十二烷基烯烃磺酸钠	对超稠油（>15000 mPa·s）的降黏率达90%以上	破乳困难	[42]
长链烷基聚醚类（POM）	对黏度为1000 mPa·s稠油降黏率为87.0%~90.6%	对高黏稠油适用性差	[43]
L季铵盐单体	对普通稠油的降黏率为99.07%，耐温抗盐性能好	合成复杂，且聚合物分子量大，破乳困难	[44]

Fig.2 Synthesis route and mechanism of action of hydrogen-bonded supramolecular polymer PTVR[47]

Fig.3 The chemical structure and microscopic image of HA1[49]

Fig.4 The synthesis route of PAAN and its emulsification mechanism with heavy oil[51]

Fig.5 Schematic mechanism of pH-responsive amphiphilic polymers[62]

Fig.6 Schematic diagram of the mechanism of temperature-responsive amphiphilic polymers[70]

Fig.7 The mechanism diagram of viscosity reduction and CO2 demulsification of MJD230[77]

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