【摘要】：隨著技術(shù)手段的提升,非常規(guī)油氣開發(fā)取得長足進步,頁巖氣作為非常規(guī)氣藏的重要組成部分,獲得廣泛關(guān)注。本文通過對頁巖氣藏孔隙結(jié)構(gòu)與吸附能力的理論和實驗研究,對其儲層微觀孔隙結(jié)構(gòu)和氣體儲集方式有了深入的認識。 本文以四川盆地龍馬溪組頁巖為研究對象,結(jié)合國內(nèi)外研究現(xiàn)狀開展研究,主要包括X射線衍射、X射線熒光、掃描電鏡、核磁共振、低壓氮氣吸附、高壓甲烷吸附等實驗。通過研究分析得到龍馬溪組頁巖巖性、地化特征、孔隙結(jié)構(gòu)和吸附能力等相關(guān)特性參數(shù)。綜合各種實驗方法,總結(jié)出了一套適合泥頁巖室內(nèi)巖心實驗的方法流程。 通過掃描電鏡觀察,本文對龍馬溪組頁巖孔隙和裂縫進行分類,按照成因來源將基質(zhì)孔隙分為無機孔隙和有機質(zhì)孔隙。無機孔隙主要包括粒狀顆粒粒間孔、黏土粒間孔、晶間孔、邊緣孔為代表的粒間孔和粒內(nèi)溶孔、生物孔組成的粒內(nèi)孔。將裂縫分為構(gòu)造張裂縫、構(gòu)造剪裂縫、層間頁理縫和成巖收縮縫。 本文利用以分形理論為基礎(chǔ)的孔隙結(jié)構(gòu)模型,結(jié)合實驗結(jié)果分析研究區(qū)內(nèi)頁巖孔隙的相關(guān)分形特征,得到了模型表征參數(shù)；通過建立多層分形吸附模型并結(jié)合對比Langmuir單層吸附模型、BET多層吸附模型和D-A模型,分析對比各個模型在頁巖氣藏擬合中的適用性。與此同時,在超臨界壓力的吸附實驗中引入擬飽和蒸汽壓概念,拓寬了BET模型和D-A模型的適用范圍。通過擬合求得D-A模型特性曲線和BET模型凈吸附熱,擬合結(jié)果相關(guān)性系數(shù)達到0.99,對樣品在未知溫度的等溫吸附情況進行預(yù)測,預(yù)測結(jié)果與實驗情況吻合。 頁巖氣的吸附量主要由頁巖內(nèi)部組成因素和外界環(huán)境因素決定。頁巖的固有吸附能力受其孔隙結(jié)構(gòu)和比表面積控制,而這兩個參數(shù)又受頁巖組成控制,這其中包括不同黏土礦物、石英和有機質(zhì)的共同作用；此外溫度、壓力和含水率也會對頁巖的吸附過程產(chǎn)生影響。
[Abstract]:With the improvement of technical means, unconventional oil and gas development has made considerable progress, shale gas as an important part of unconventional gas reservoirs, has received extensive attention. Based on the theoretical and experimental study on pore structure and adsorption capacity of shale gas reservoirs, this paper makes a deep understanding of the microscopic pore structure and gas reservoir mode of shale gas reservoirs. In this paper, the shale of Longmaxi formation in Sichuan Basin is taken as the research object, and the research is carried out at home and abroad, including X-ray diffraction X-ray fluorescence, scanning electron microscope, nuclear magnetic resonance, low pressure nitrogen adsorption, high pressure methane adsorption and so on. The shale lithology, geochemical characteristics, pore structure and adsorption capacity of Longmaxi formation were obtained. In this paper, a set of methods for core experiment in shale is summarized by synthesizing all kinds of experimental methods. The shale pores and fractures of Longmaxi formation were classified by SEM, and the matrix pores were divided into inorganic pores and organic pores according to the origin. Inorganic pores mainly include granular intergranular pores, clay intergranular pores, edge pores represented by intergranular pores and intragranular dissolved pores, and biopore composed of intragranular pores. The fractures are divided into structural tensional fractures, structural shear fractures, interlaminar lamellar fractures and diagenetic shrinkage joints. In this paper, the pore structure model based on fractal theory is used to analyze the fractal characteristics of shale pores in the study area, and the characterization parameters of the model are obtained. By establishing multilayer fractal adsorption model and comparing Langmuir monolayer adsorption model with Langmuir multilayer adsorption model and D-A model, the applicability of each model in shale gas reservoir fitting is analyzed. At the same time, the concept of quasi saturated vapor pressure is introduced into the adsorption experiment of supercritical pressure, which widens the application range of BET model and D-A model. By fitting the characteristic curve of D-A model and the net adsorption heat of BET model, the correlation coefficient of the fitting results is 0.99. The isothermal adsorption of the sample at unknown temperature is predicted, and the predicted results are in good agreement with the experimental results. The adsorption capacity of shale gas is mainly determined by the internal composition of shale and external environmental factors. The inherent adsorption capacity of shale is controlled by its pore structure and specific surface area, and these two parameters are controlled by shale composition, which includes the interaction of different clay minerals, quartz and organic matter, in addition to temperature, Pressure and moisture content also affect the adsorption process of shale.
【學(xué)位授予單位】：西南石油大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：P618.13

【參考文獻】

相關(guān)期刊論文 前3條

1 龐小麗;劉曉晨;薛雍;江向鋒;江超華;;粉晶X射線衍射法在巖石學(xué)和礦物學(xué)研究中的應(yīng)用[J];巖礦測試;2009年05期

2 馬新仿,張士誠,郎兆新;儲層巖石孔隙結(jié)構(gòu)的分形研究[J];中國礦業(yè);2003年09期

3 孫洪泉,謝和平;分形插值曲面及其維數(shù)定理[J];中國礦業(yè)大學(xué)學(xué)報;1998年02期

，

本文編號：2252267