With the development of EOR technologies, the ASP flooding technology of Daqing oilfields has become mature step by step. For years of research and practice, Daqing has established a comprehensive ASP industrial application technology, including research and manufacturing of surfactant, study of the mechanism of ultra-low interfacial tension, surface injection allocation technique and lifting techniques. At present, the large-scale industrial field tests on ASP flooding have been carried out in Daqing oilfields. ASP flooding is going to be the dominant technology in the ultrahigh water cut development phase. The development of ASP technology experienced three stages. First stage is laboratory experiments stage. Having the property of low acid number and high wax content, Daqing oil had been thought hardly to be applied with ASP technology. However, in 1988, formulas had been screened which achieved an ultra-low IFT with Daqing oil. Physical simulation experiments indicated that the final oil recovery achieved to 20% OOIP over that of water flooding.1-3 Second stage is pilot field tests stage. Daqing oilfields had completed 5 ASP flooding pilot field tests since 1994. All have gotten high displacement efficiency which according with the laboratory results. Third stage is industrial pilot tests stage. Daqing implemented the development and production of alkyl benzene sulfonate (adapt to strong base and weak base) with independent innovation. Since year 2000, several industrial ASP flooding tests have been carried out successively which have shown a satisfied effect of higher oil production and lower water cut. The field test scale is from 1 injector-4 producers to 6 injectors-12 producers. These days, large-scale industrial field application is ongoing in Daqing oilfields.
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