页岩油资源评价关键参数——含油率的校正

Correction of oil content—one key parameter in shale oil resource assessment

页岩油资源评价过程中,常用热解参数S1(游离烃含量)与氯仿沥青"A"含量反映含油性。但由于实验流程的原因,所测得的S1存在着轻烃、重烃的损失,氯仿沥青"A"含量存在着轻烃损失。为了更准确地对页岩油资源进行定量评价,通过对松辽盆地北部青山口组泥页岩有机质成烃动力学研究以及对样品抽提前、后的热解参数进行对比,对氯仿沥青"A"含量进行轻烃补偿校正,对S1进行轻烃、重烃补偿校正,以获得泥页岩总含油率参数。结果表明,松辽盆地北部青山口组泥页岩校正后S1约为校正前S1平均值的4.2倍,校正后氯仿沥青"A"含量约为校正前氯仿沥青"A"含量平均值的1.2倍。校正前S1仅为氯仿沥青"A"含量的0.28倍,校正后S1与氯仿沥青"A"含量基本相同。可见在页岩油的资源评价过程中,对S1与氯仿沥青"A"含量的补偿校正是十分必要的。

Pyrolysis parameter S1 （content of free hydrocarbon） and chloroform-extractable bitumen＂ A＂ are often used to reflect oil content during shale oil resource assessment. However, due to inherent flaws of experimental procedures, laboratory-measured S1 values fail to truthfully record the loss of light （bitumen＂ A＂ only） and heavy hydrocarbons and the measured bitumen＂ A＂values cannot truthfully record the loss of light hydrocarbons. In order to be more accurate in quantitative assessment of oil shale resources, we performed correlation of these parameters to mend up the losses based on analyses of hydrocarbon genesis kinetics of organic matter and comparison of the parameters before and after extraction experiments on samples from mudstone/shale of the Qingshankou Formation in Songliao Basin. The results show that the correlated average S1 and bitumen＂ A＂ are 4. 2 and 1.2 times higher than the measured average ones, respectively. The S1 equals to bitumen＂ A＂ after correction,while the former is only 0. 28 times the value of the latter before correction. This indicates the necessity of correction to the two parameters in the resource assessment.