Research on the Remaining Oil Starting Mechanism in Different Pores of Polymer Surfactants Using NMR Analysis

Abstract:

With its unique structure and properties, polymer surfactants have been used in chemical flooding. Compared with ordinary polymer, polymer surfactants have a higher recovery degree. However, remaining oil starting mechanism in different pores using different polymer surfactants after water flooding is still unclear. NMR (Nuclear Magnetic Resonance) has a good effect on determination of rock oil saturation and analysis of pore structure. In this paper, oil displacement experiment using kerosene which contains no hydrogen was conducted and the problem caused by the similarity between oil phase relaxation time and water relaxation time in large pores was overcome. Through the change of NMR relaxation time, oil distribution situation in different pores of ordinary polymer, refining III polymer surfactant, and Haibo III polymer surfactant after polymer flooding was measured accurately. This paper also quantitatively analyzed the contribution degree to oil recovery in pores of different sizes, and evaluated oil displacement effect of the above three kinds of oil displacement systems. The results show that when only the swept volume is considered, recovery degree of Haibo III polymer surfactant is higher, reaching 53.66%. In different systems, middle pores contribute most to recovery degree. At the same time, the remaining oil in middle pores and large pores accounts more, which is the main attack direction towards tapping the potential of remaining oil in the oilfield.

• Periodical: Advanced Materials Research (Volumes 1010-1012)
• Pages: 1727-1734
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1010-1012.1727
• Online since: August 2014
• Authors: Yi Qiang Li, Zhe Yu Liu*, Yan Yue Li, Yi Bo Xu
• Keywords: NMR (Nuclear Magnetic Resonance), Polymer Surfactants, Remaining Oil, Starting Mechanism

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