不同结构配比的鼠李糖脂乳化活性与油泥清洗效果

以大庆油田原油和含油污泥为对象,研究不同结构配比鼠李糖脂表面活性剂乳化活性及其对含油污泥清洗效果的影响,并优化清洗工艺参数。结果表明:单鼠李糖脂比例越高,其表面活性越好;双鼠李糖脂比例越高,其对原油的乳化能力越强;临界胶束浓度随着双鼠李糖脂比例的增加而逐渐加大;单、双鼠李糖脂配比不同的表活剂对油泥的清洗效果也不同,质量比为50∶50时清洗效率最高;鼠李糖脂浓度为1.0 g·L^-1、热洗时间为1.5h、热洗温度为65℃、洗脱强度为220 r·min^-1、固液质量比为1∶5条件下,油泥的清洗效率最高,可达81.3%;含油率为29.6%的落地油泥,经一级洗涤后油泥残油率降至5.5%,原油回收率达到87.3%,清洗出的原油无明显乳化,易于分离。由此可知,鼠李糖脂的单、双糖脂比例不同对其理化性质和清洗含油污泥的效果均有不同程度的影响。

Effects of rhamnolipids with different structure ratios on the emulsification activity and oily sludge cleaning

Physicochemical activities and oily sludge cleaning effect of rhamnolipids with different structure compositions were examined using crude oil and oily sludge of Daqing Oilfield.Meanwhile,the parameters of oily sludge cleaning were optimized. Results showed that there was a positive relationship between the proportion of mono-rhamnolipids and surface activity of rhamnolipids. The proportion of di-rhamnolipids was positively correlated with emulsifying ability of rhamnolipids to crude oil. Different ratios of mono-rhamnolipids and di-rhamnolipids affected oily sludge cleaning effect. The cleaning efficiency was the highest at a ratio of 50: 50. The optimized cleaning parameters were as follows: rhamnolipids concentration of 1.0 g·L^-1,hot wash time of1.5 h,hot wash temperature of 65 ℃,eluting power of 220 r·min^-1,and solid-liquid ratio of1: 5. The cleaning efficiency was up to 81.3% under optimized conditions. After cleaning process,oil content of the ground oily sludge was reduced from 29.6% to 5.5%. The oil recovery efficiency was 87.3%. The washed crude oil has no obvious emulsification and is easy to separate. Different ratios of mono-rhamnolipids and di-rhamnolipids affect their physicochemical properties and the oily sludge cleaning effect.