The Study on Interfacial Characteristic of the Hydroxy Sulfobetaine and Complex Systems
|School||Northeast University of Petroleum|
|Course||Oil and Gas Field Development Project|
|Keywords||surfactant ultra-low interfacial tension adsorption hydroxy sulfosalicylic betaine carboxyl betaine oil displacement efficiency|
The technology of combination flooding has advanced in the world in our country. At present, ASP flooding has entered into the stage of industrial application. The results of laboratory and fields tests show that the recovery of ASP system can be increased by more than 20% on the basis of water flooding. Especially during the period of the“Eleventh Five-Year”, ASP flooding will become one of the important measures that ensure a high and stable yield in Daqing oil field. However, the problems brought by itself limited the promotion of ASP flooding, that the difficulties to deal with produced fluid and the damage to the formation. Surfactant-polymer binary flooding （SP flooding） becomes one of the aims in combination flooding because the surfactant and the polymer can develop their biggest advantages. In the SP flooding,the key is find a steady surfactant that can reach a ultra-low-tension of 10-3mN/m with Daqing crude in alkali-free condition.In this paper, it mainly evaluates the interfacial characteristics of the hydroxy sulfosalicylic betaine surfactant and its compound systems to apply in alkali-free displacement, we found the optimum surfactant to do the experiment of adsorption, stability and the research on physical simulation experiment of oil displacement. Moreover, the text investigate the influence of surfactant concentration、polymer concentration、polymer molecular weight and salinity on the hydroxy sulfosalicylic betaine surfactant; inspect the rock core displacement characteristics of SP binary system and ASP ternary system which use B,B&SB8 binary system under the condition of DaQing oil field.The results show that: the single B surfactant can effectively reduce the oil-water of one plants in Daqing, when the concentrations are 0.3%,0.1%,0.02% and 0.05%, the interfacial tension reached a ultra-low-tension of 10-3mN/m; Sample B could make the oil-water interfacial tension of one plants in Daqing reach a ultra-low-tension (<10-3mN/m,orders of magnitude) in a wide range surfactant concentration by adding in 19 million molecular weight polymer produced by Daqing Oil Refining and Chemical Company when the concentration of polymer is 1500PPM; the molecular weight and concentration of polymer have a great influence on the interfacial tension; Sample B in 0.2% concentration is steady, the interfacial tension was almost between （5.06.0）×10-3mN/m; the polymer had a little influence on the adsorption of SY, and had some influence when betaine and polymer compound; we explored two kinds of proportion in Sample B and SB8 which can make the oil-water interfacial tension of one plants in Daqing reach a ultra-low-tension of 10-3mN/m adding in the polymer; analyzed the experimental results, we recommend to use BS alkali-free binary system and NaOH ternary system on rock core which percolation rate is 300×10-3μm2and 150×10-3μm2, and use BS alkali-free binary system on rock core which percolation rate is50×10-3μm2.