Impact of Pore Connectivity on Quantification of Mineral Accessibility in Sandstone Samples
Impact of Pore Connectivity on Quantification of Mineral Accessibility in Sandstone Samples
复制标题
孔隙连通性对砂岩样品中矿物可及性定量的影响
DOI：
10.1021/acsearthspacechem.2c00099
复制
发表时间：
2022
影响因子：
3.4
通讯作者：
Beckingham, Lauren E.
中科院分区：
文献类型：
--
作者：
Salek, Md. Fahim;Qin, Fanqi;Asadi, Parisa;Iloejesi, Chidera;Brunhoeber, Olivia;Mahmood, Mukseet;Beckingham, Lauren E.
通过成像分析，可以非破坏性地描述岩石样品中的微尺度特征和矿物分布。扫描电子显微镜与背散射电子和能量色散光谱相结合特别有价值，可以用来识别矿物。矿物分割与定量图像处理相结合，可以从这些图像中得到矿物体积分数和可及性。之前从图像中对矿物可获得性的估计改进了对矿物反应速率的模拟，但尚不清楚应该如何解释孔隙连通性。在含有粘土矿物的样品中，这一点更加复杂，需要考虑粘土中的纳米孔。在这里，考虑了7个不同成分的砂岩样品，不同的孔隙连通性评估方法对矿物可获得性量化的影响。矿物可及性是通过计算二维矿物分割图中伴生矿物与相邻孔隙之间的界面像素来计算的。考虑了三种类型的可达性：第一种方法考虑了所有的大孔隙，第二种方法只考虑了二维连通大孔隙，第三种方法考虑了粘土中纳米孔的二维连通孔隙度。当考虑纳米孔连通性时，观察到的大多数矿物相的可及性变化在1个数量级内，因此预计不会对样品的模拟反应性产生很大影响。然而，观测到的粘土矿物的变化更大，这可能会影响长期模拟(年)。碳酸盐矿物的可及性差异也较大，但只有一些样品含有碳酸盐相，需要更多的数据来评估这种趋势。
Characterization of microscale features and mineral distributions in rock samples can be facilitated non-destructively with imaging analysis. Scanning electron microscopy combined with backscattered electron and energy-dispersive spectroscopy is particularly valuable and can be utilized to identify minerals. Mineral segmentation coupled with quantitative image processing can yield mineral volume fractions and accessibility from these images. Prior estimates of mineral accessibility from images have improved the simulations of mineral reaction rates, but it is unclear how pore connectivity should be accounted for. This is further complex in samples with clay minerals where nanopores in clays need to be considered. Here, the impacts of different approaches to assess pore connectivity on quantification of mineral accessibility are considered for seven sandstone samples with varying composition. Mineral accessibilities are calculated by counting the interfacial pixels between the associated minerals and the adjacent pores from the 2D mineral segmented maps. Three types of accessibilities are considered: the first approach accounts for all the macropore space, the second approach considers only the 2D connected macropores, and the third approach includes the 2D connected porosity considering nanopores in clays. The observed variations in accessibility for most mineral phases are within 1 order of magnitude when nanopore connectivity is considered and thus not anticipated to largely impact the simulated reactivity of samples. However, greater variations were observed for clay minerals, which may impact long-term simulations (years). Larger variations in accessibility were also noted for carbonate minerals, but only some samples contained carbonate phases, and additional data is needed to assess the trends.
登录
查看更多内容
影响因子：
3.4
作者：
Qin, Fanqi;Beckingham, Lauren E.
通讯作者：
Beckingham, Lauren E.
影响因子：
4.6
作者：
Sandhu D;Singh A;Duranceau SJ;Nam BH;Mayo T;Wang D
通讯作者：
Wang D
图像分辨率对矿物丰度和可及表面积量化的影响
影响因子：
3.9
作者：
F. Qin;L. Beckingham
通讯作者：
L. Beckingham
汉福德沉积物与苛性罐废物反应后孔隙网络结构的变化。
影响因子：
3.6
作者：
L. E. Crandell;C. Peters;W. Um;K. Jones;W. Lindquist
通讯作者：
W. Lindquist
花岗岩土壤的表面积和反应性： I. 根据现场观测推导出的原生矿物溶解速率与深度和年龄的函数关系
影响因子：
6.1
作者：
Samuel A. Parry;M. Hodson;S. Kemp;E. Oelkers
通讯作者：
E. Oelkers