泥页岩纳—微米微孔隙封堵评价方法

针对普遍存在于泥页岩中的纳—微米孔隙结构，很少有可靠的方法对其进行封堵实验评价。目前，模拟评价泥页岩微孔隙的介质，大多是人造岩心、砂盘以及微裂缝等，尺寸大多处于微米级别以上，很难达到泥页岩所具有的纳米级微孔隙。针对该难题，通过电镜扫描和岩心驱替实验等分析方法，选取微孔隙尺寸大小、孔隙度以及渗透率与龙马溪泥页岩相当的露头泥页岩制备岩心，并使用泥页岩微孔隙封堵效果评价装置，进行动态封堵压力传递实验。介绍了该装置的组成、操作方法以及特点，给出了封堵效率的计算公式。通过室内封堵压力传递实验，验证了该装置稳定性好和重复性好等优点。实验结果表明，该装置及方法能较好地评价不同加量，提高不同种类纳米材料对泥页岩微孔隙的封堵效率，还能够筛选出合适性能优异的纳米封堵材料，为解决泥页岩井壁难题提供了一种扎实可靠的实验新方法。

Evaluation method of mud shale nano-micron pore sealing

Few reliable methods are for blocking experimental evaluation of nano-micron pore structure in mud shale.At present，the simulation evaluation of mud shale，micro pore medium is mostly artificial core，sand disc and microfracture，most size in micron level above，and it was difficult to achieve the hard brittle shale of nanoscale micro pore.Aiming at the problem，through the electron microscope scanning and core displacement experiment analysis methods，such as selection of micro pore size，porosity and permeability and creek，the dragon of mud shale outcrop the preparation of the core of the shale quite a bit，and use the micro pore blocking effect evaluation of the shale device，the dynamic sealing pressure transmission experiment.This paper also introduced the composition，operation method and characteristics of the device，and gave the calculation formula of plugging efficiency.The experimental results showed that the stability and repeatability of the device were good.The experimental results showed that the device and method can better evaluate different added amount，different kinds of nano materials on the micro pore plugging efficiency of the shale，will also be able to select appropriate nanoscale sealing material，the best performance in order to solve the sidewall of the shale problem provided a reliable experimental method.