【摘要】 以某油田作为油相,研究了不同浓度的碱(苛性碱与碳酸钠)与阴-非离子表面活性剂(AEC、AES)复配体系在55℃时与原油油水界面张力行为。首先通过阴-非离子表面活性剂与地层水的配伍性实验筛选合适的阴-非离子表面活性剂;然后通过碱与筛选出来的表面活性剂复配,研究不同浓度下碱对该表面活性剂的界面张力的影响效果。研究结果表明:0.01%~1.20%Na OH分别与0.1%AES和0.3%AEC组成的复配体系体系以及0.01%~1.20%Na2CO3分别与0.1%AES和0.3%AEC组成的复配体系体系能够产生一定的协同效应,使得油水界面张力逐渐降低,最终都能达到10-3m N/m的超低界面张力,而且在相同浓度的Na OH、Na2CO3下,含AES的复配体系要比含AEC的复配体系所得到界面张力低。考虑到碱耗以及对储集层伤害的影响,选择0.6%~1.2%Na2CO3与0.1%AES复配体系能更好的达到降低油水界面张力、提高油田采收率的目的。更多还原

【Abstract】 Using crude oil from an oilfield as the oil phase, the interfacial tension between oil and water with different concentrations of alkali(caustic soda and sodium carbonate) and anionic-nonionic surfactants(AEC, AES) was investigated.Firstly,the suitable anionic and nonionic surfactants were screened out by the compatibility experiment of anionic and nonionic surfactants with formation water, then the effect of the alkali on the interfacial activity was studied by mixing the screened surfactants with different concentrations of alkali. The results showed that the compounded systems composed of 0.01%~1.20% Na OH with 0.1% AES,0.01%~1.20% Na OH with 0.3% AEC,0.01% ~ 1.20% Na2 CO3 with 0.1% AES,and 0.01% ~ 1.20% Na2 CO3 with 0.3% AEC could create synergistic effect, which gradually reduced the oil-water interfacial tension to ultimately reach ultra-low 10-3 m N/m interfacial tension. Under the same concentration of Na OH and Na2 CO3, the interfacial tension of the composite system containing AES was lower than that of the composite system containing AEC. Taking into account the alkali loss and the impact on reservoir damage, 0.6% ~ 1.2% Na2 CO3 and 0.1% AES compound system should be chosen to achieve the purpose of reducing oil-water interfacial tension and improving oil recovery.更多还原