摘要
分子沉积(MD)膜驱油是提高原油采收率的一种新方法。在题示实验研究中所用MD膜驱剂MD 1是一种分析纯单分子双季铵盐,油砂未洗油,取自辽河兴隆台109井。介绍了溴百里酚蓝为指示剂测定水溶液中MD 1质量浓度的方法,在10~300mg/L范围内溶液吸光度与浓度之间有良好的线性关系。MD 1在油砂上的吸附很快,在25℃下4h即基本达到平衡,吸附量随MD 1溶液pH值升高而增大,pH值在2~4之间时增加快,在4~9之间时增加慢,在9~12之间时又增加快,由此确定吸附主要是静电作用的结果,油砂表面的电荷性质和电荷量是决定吸附的主要因素。吸附等温线符合Langmuir定律,即为单分子层吸附,计算求得25℃和40℃时饱和吸附量分别为13.04和12.68mg/g油砂,吸附热为-15.2kJ/mol。在吸附MD 1后的油砂上汽油的相对接触角由43.68°增大至49.56°,油砂表面亲油性减弱,亲水性增强。在油砂上吸附成膜时放热,成膜表面润湿性改变,是MD膜驱剂提高原油采收率的2个重要因素。图4表1参12。
Molecular deposition filming flooding (MDFF) is a newly developed method of EOR. The MDFF agent under study, MD1, is an organic diammonium compound of analytical pure and the reservoir core sand is taken from production well X109 of Xinglongtai, Liaohe. The determination of MD1 concentration (in mg/L) in aqueous solution by using bromthymol blue indicator method is described and a linear relationship is observed between absorbance and solution concentration ranged in 10-300 mg/L. The adsorption on oily sand of MD1 from aqueous solution proceeds very fast and reaches equilibrium practically in 4 hrs at 25℃. The adsorption increases with increasing solution pH value fast in pH range 2-4, slowly in pH rang 4-9 and fast again in pH range 9-12 and from these data it is ascertained that the adsorption results from static electric intereactions and the nature and the amount of electric charges on sand surfaces are the principle factors in adsorption. The adsorption isotherms are of Langmuirs type and indicate monomolecular adsorbed layer formation; the saturated adsorption of MD1 on oily sand calculated accounts 13.04 mg/g at 25℃ and 12.68 mg/g at 40℃ and the adsorption heat--15.2 kJ/mol. The relative contact angle of gasoline on oily sand surfaces before and after MD1 adsorption is of 43.68° and 49.56°, respectively, and shows the weakening of oleophilicity or enhancing of hydrophobilicity for oily sand surfaces with MD1 adsorbed. Exothermic effect of adsorption processes and wettability change of oily sand surfaces might be considered two of the main factors in enhanced oil recovery by using MDFF agent.
出处
《油田化学》
CAS
CSCD
北大核心
2003年第1期70-73,共4页
Oilfield Chemistry
基金
中国石油天然气股份公司导向试验基金资助(B9802)。
关键词
MD-1膜驱剂
油砂
研究
表面吸附
分子沉积膜驱剂
双季铵盐化合物
水溶液吸附
表面润湿性
molecular deposition (MD) filming flooding agent
organic diammonium compound
oily reservoir sand
adsorption from aqueous solution
surface wettability