%0 Journal Article
%T Impact of Ultra-Low Interfacial Tension on Enhanced Oil Recovery of Ultra-Low Permeability Reservoir
%A Lin ZHAO
%A Aifen LI
%A Haojun XIE
%A Yuli ZHANG
%J Advances in Petroleum Exploration and Development
%D 2012
%I 
%R 10.3968/j.aped.1925543820120401.721
%X Ultra-low permeability reservoirs have the characteristics of complex pore throat structure, generally higher injection pressure and lower oil recovery. By means of casting thin sections, pore structure of selected ultra-low permeability core was surveyed. The core was classified into low porosity, low permeability and without natural fractures. Vast majority of throats of the core varied in width from 2.5 ¦Ìm to 15 ¦Ìm. Core displacement experiments showed that surfactant flooding could have certain effect of reducing injection pressure and enhancing oil recovery. When interfacial tension was 5.93¡Á10-2 mN/m, decompression rate reached 7.65%, and recovery was improved by 4.09%. And when interfacial tension was 4.9¡Á10-5 mN/m, decompression rate reached 25%, and recovery was improved by 11.6%. The lower interfacial tension is, the better the effect of reducing injection pressure is, and the higher the extent of enhancing oil recovery is. In general, surfactants have a great application prospect on the oil field development of ultra-low permeability reservoir, and the interfacial tension should be reduced as far as possible. Key words: Low permeability; Surfactant; Interfacial tension; Emulsion; Enhancing oil recovery
%K Low permeability
%K Surfactant
%K Interfacial tension
%K Emulsion
%K Enhancing oil recovery
%U http://cscanada.net/index.php/aped/article/view/2852