页岩游离油量实验定量表征方法OA

The free oil content in shale is a key parameter necessary for evaluating shale oil resources and shale oil content.Scientifically and reasonably quantifying this parameter is an inevitable requirement for shale oil area selection evaluation and exploration deployment.Due to limitations in technical means,understanding of mechanisms,and sample quality,early models for calculating free oil have problems such as large errors in the recovery of light hydrocarbon loss without calibration by sealed coring wells,significant differences in geochemical parameters between free oil and produced shale oil in shale,and failure to consider underground factors such as rock wettability in adsorption capacity.Based on experimental analysis and testing techniques,testing of free oil content in shale samples from the upper submember of the fourth member of the Eocene Shahejie Formation(Es4U)in Dongying Sag was performed.Indirect and direct methods were used to establish quantitative characterization methods for experiments on free oil content in shale.The indirect method mainly considers the experimental conditions of retained oil,recovers relevant experimental parameters reasonably,and focuses on studying the influence of shale water saturation on adsorbed oil.Shale oil adsorption experiments with different water saturations were conducted to form an experimental method for indirect quantitative characterization of free oil in shale.The direct method is based on the principle that the oil parameters(fluorescence spectrum's main peak wavelength and red-green entropy value)of shale oil from the drilling wellbore and from shale samples extracted step by step are basically the same.By determining a reasonable pyrolysis temperature representing the free oil content of shale,experimental conditions such as solvent composition,extraction time,sample particle size,and extraction method for step extraction were established to directly quantify the free oil content in shale.The consistency between indirect and direct testing results indicates that the established experimental method has good accuracy,achieving quantitative characterization of free oil content in shale,further improving shale oil resource evaluation and shale oil content evaluation methods,and providing more reliable analysis and testing parameters for shale oil exploration,evaluation deployment,and reserve declaration.The experimental quantitative characterization method for free oil content of shale has been successfully applied to the exploration and evaluation deployment of shale oil in the Jiyang Depression,indicating that the method has good practical application value.