CAJ | 학술논문

通过全岩和黏土矿物X－衍射、索氏抽提、离子抛光、扫描电镜、低温氮气吸附、等温吸附等实验分析，研究了鄂尔多斯盆地延长组湖相页岩储层中的液态烃对吸附气含量的影响。结果表明，延长组湖相页岩储层正处于中成岩阶段A期；有机质演化程度相对较低，不足以形成大量的有机质孔隙，却足以形成大量的液态烃，液态烃占据了页岩中直径约4 nm左右的孔隙。由于氮气不溶于液态烃，而甲烷易溶解于液态烃，使得抽提前后样品低温氮气吸附实验得到的比表面积和吸附量变化大，但抽提前后样品等温吸附实验测得的甲烷“吸附”量变化不大，这表明等温吸附实验中有一部分甲烷以溶解态赋存于页岩样品中。因此在用等温吸附实验研究低成熟度页岩吸附气含量的过程中，必须注意液态烃的影响。
통과전암화점토광물X－연사、색씨추제、리자포광、소묘전경、저온담기흡부、등온흡부등실험분석，연구료악이다사분지연장조호상혈암저층중적액태경대흡부기함량적영향。결과표명，연장조호상혈암저층정처우중성암계단A기；유궤질연화정도상대교저，불족이형성대량적유궤질공극，각족이형성대량적액태경，액태경점거료혈암중직경약4 nm좌우적공극。유우담기불용우액태경，이갑완역용해우액태경，사득추제전후양품저온담기흡부실험득도적비표면적화흡부량변화대，단추제전후양품등온흡부실험측득적갑완“흡부”량변화불대，저표명등온흡부실험중유일부분갑완이용해태부존우혈암양품중。인차재용등온흡부실험연구저성숙도혈암흡부기함량적과정중，필수주의액태경적영향。
The effect of liquid hydrocarbons on the gas adsorption capacity of lacustrine shales from the Yanchang Formation in the Ordos Basin has been studied using a series of integrated experimental methods including X?ray diffraction of bulk and clay minerals, Soxhlet extraction, focused ion beam scanning electron microscopy(FIB-SEM), low?temperature N2 adsorption and high?pressure CH4 adsorption methods. The results show that the lacustrine shale from the Yanchang Formation is in the middle diagenetic stage A. The thermal maturity is relatively low, and contributes to the absence of organic matter pores. However, it is sufficiently high enough forthe production of liquid hydrocarbons which can block up pores with a diameter of 4 nm. Methane can dissolve in these liquid hydrocarbon, whereas nitrogen cannot. As a result, the specific area and adsorbed capacity acquired in low?temperature N2 adsorption analysis show great differences between samples before and after extraction. However, the difference does not exist in the CH4 adsorption analysis. This means that a certain proportion of CH4 exists in these samples in a dissolved form. It is necessary to pay attention to free hydrocarbons during studies of gas adsorption capacity of shales with low thermal maturity usinghigh pressure CH4 adsorption methods.