State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Sinopec Petroleum Exploration and Production Research Institute, Beijing, China.
Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil & Gas Reservoirs, Xi'an Shiyou University, Xi'an, Shaanxi, China.
PLoS One. 2020 Oct 1;15(10):e0239662. doi: 10.1371/journal.pone.0239662. eCollection 2020.
Electromagnetic radiation has been proposed to non-aqueously stimulate shale formations, which can generate fractures and enhance the porosity of the matrix. The proposed method consumes electricity and thereby possesses significant advantages for sustainable and environmental hydrocarbon production. In this study, we investigate the pore structure variations of marine shale during electromagnetic radiation. First, the prepared marine shale samples are exposed to electromagnetic radiation for different times; an infrared thermometer monitors the temperatures. Then, the nitrogen adsorption/desorption technique is applied to examine the evolutions of the pore structure. Next, a scanning electron microscope is adopted to reveal the morphology and identify newly developed pores. Lastly, fractal analyses are performed to quantify pore structure variations. The sample exhibits quick temperature rises, whose temperature reaches about 300 °C after 5 min of electromagnetic radiation. The elevated temperature causes clay dehydration, thermal expansion, and organic matter decomposition, leading to significant changes in pore structures. The nitrogen adsorption/desorption characteristics demonstrate enhancements in pore spaces, including volume, size, and surface area. Fractal analyses show that the pores become rougher and exhibit less heterogeneity after electromagnetic radiation. The obtained results demonstrate a great potential of using electromagnetic radiation to enhance the porosity of shale rocks.
电磁辐射被提议用于非水相刺激页岩地层，这可以产生裂缝并增强基质的孔隙率。所提出的方法消耗电力，因此对于可持续和环境烃类生产具有显著优势。在这项研究中，我们研究了电磁辐射过程中海洋页岩的孔隙结构变化。首先，将制备好的海洋页岩样品暴露于电磁辐射下不同的时间；红外温度计监测温度。然后，应用氮气吸附/解吸技术来检查孔隙结构的演变。接下来，采用扫描电子显微镜揭示形貌并识别新开发的孔隙。最后，进行分形分析以量化孔隙结构变化。样品表现出快速升温，在电磁辐射 5 分钟后，温度达到约 300°C。升高的温度导致粘土脱水、热膨胀和有机质分解，从而导致孔隙结构发生显著变化。氮气吸附/解吸特性表明孔隙空间得到了增强，包括体积、尺寸和表面积。分形分析表明，电磁辐射后孔隙变得更加粗糙，异质性降低。所得结果表明，使用电磁辐射来增强页岩岩石的孔隙率具有很大的潜力。
