陇东油区包气带土壤对原油吸附行为

Crude oil adsorption behaviors in the soil of Longdong oilfield

通过静态吸附实验研究了陇东油区包气带土壤对原油的吸附行为,考察了溶液pH、温度、石英砂及不同介质对原油吸附的影响.结果表明:陇东土壤对原油吸附等温线很好地符合Langmuir和线性吸附方程,其吸附系数为0.0135,0.0126L/g,且在水相中原油快速吸附到土壤颗粒上,5h后基本达到平衡.5种介质吸附原油能力依次为石英砂<高岭土<黄绵土<高压灭菌土<硅藻土.水相pH、温度和石英砂质量分数的升高,不利于原油在土壤中的吸附,而增加盐度会加大原油的吸附量.对于土壤偏碱性,砂粒质量分数高的陇东地区,这些特性有利于原油在包气带土壤中向下运移.

Adsorption behaviors of crude oil in aeration zone soil in Longdong oilfield were studied through static experiments and the factors such as pH,temperature,quartz sand and different media were investigated.The results indicated that the adsorption isotherms of crude oil in soil samples of Longdong corresponded very well with the Langmuir and linear equation.The adsorption coefficients were 0.013 5 and 0.012 6 L/g,and in the aqueous phase,crude oil could soon be absorbed in the soil particle,reaching a balance after 5 hours.The order of adsorption capacity of crude oil in the five media was：silica sand〈kaolin〈 loessal soil 〈high pressure sterilized soildiatomite.The increase of pH,temperature and silica sand was not favorable to the adsorption of crude oil in soil,but increasing the salinity could improve the adsorption.Therefore these specialties were beneficial to crude oil＇s downward migration in the aeration zone in Longdong oilfield,where there existed alkaline and a big content of sand gravel in soil.