页岩比表面积与孔隙结构关系的分析

比表面积和孔隙结构是页岩的两个重要特性。比表面积对于岩石基质的吸附特型和膨胀性能具有重要的影响。现有的比表面积测量方法在测定页岩比表面积时,由于页岩含有大量微纳米孔隙,测得的页岩比表面积精度不高。研究基于比表面积与孔隙结构的关系,建立比表面积与孔隙结构之间的数学模型,并讨论了随孔隙在基质中的数量比例和体积比例两种参数下,页岩的比表面积与孔隙结构之间的关系。结果表明微孔对于页岩的比表面积具有重要贡献,且比表面积与小孔隙的体积占比之间为正相关关系,与小孔的数量占比之间则需要通过不同情况来进行判断。为页岩气的吸附特征研究和岩石的膨胀特性研究提供了一定的理论依据。

Analysis of the Relationship between Specific Surface Area and Pore Structure of Shales

The Specific surface area and pore structure are two important characteristics of shale. The specific surface area has an important influence on the adsorption characteristics and expansibility of shale. When measuring the specific surface area of shale gas, the result of specific surface area of shales is not so precise because of a large number of micro-nano pores. Based on the relationship between the specific surface area and space structure, the mathematical model is established, and the relationship between the specific surface area and pore structure of shale is discussed with two parameters, the number ratio and volume ratio. Results show that the microporous for specific surface area has important contribution to the shale, and small specific surface area is positive correlation relationship with pore volume ratio. This paper provides a theoretical basis for the study of shale gas adsorption characteristics and shale expansion characteristics.