The impact of residual water on CH4-CO2 dispersion in consolidated rock cores
The impact of residual water on CH4-CO2 dispersion in consolidated rock cores
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DOI：
10.1016/j.ijggc.2016.04.004
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发表时间：
2016-07
影响因子：
3.9
通讯作者：
A. Honari;M. Zecca;S. J. Vogt;S. Iglauer;B. Bijeljic;M. Johns;E. May
中科院分区：
文献类型：
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作者：
A. Honari;M. Zecca;S. J. Vogt;S. Iglauer;B. Bijeljic;M. Johns;E. May
将CO2注入天然气储层中，提高天然气采收率（EGR）的可行性评估需要准确和适当的储层模拟。这些需要提供描述流体之间的分散的参数。在这里，我们系统地测量流体分散在各种岩心（砂岩和碳酸盐岩），无论是干的和束缚水饱和度，在油藏条件。以这种方式，我们评估的影响，束缚水的混相驱替过程。因此，这代表了在固结介质中作为超临界气体的水饱和度的函数的分散的第一测量。使用磁共振技术对水沿岩石轴沿着的空间分布以及水所占据的孔径分布进行补充测量。束缚水被发现增加分散性的一个因素高达7.3。分散系数（K）作为速度的函数进行测量，干燥和含水样品的数据成功地结合在aK-Péclet数（Pe）图上，使未来的EGR储层模型。KuponPe的幂律依赖性对于干燥和水饱和的砂岩产生1.2的指数，对于干燥和水饱和的碳酸盐产生1.4的指数，与文献结果一致（Bijeljic等人，2011年，Honari等人，2015）。
Assessment of the viability of enhanced gas recovery (EGR), in which CO2is injected into natural gas reservoirs, requires accurate and appropriate reservoir simulations. These necessitate provision of parameters describing dispersion between the fluids. Here we systematically measure fluid dispersion in various rock cores (sandstones and carbonates), both dry and at irreducible water saturation, at reservoir conditions. In this manner we evaluate the impact of the irreducible water on the miscible displacement processes. As such this represents the first measurement of dispersion as a function of water saturation for supercritical gases in consolidated media. Complementary measurements of water spatial distribution along the rock axis, as well as the pore size distribution occupied by the water were performed using magnetic resonance techniques. Irreducible water was found to increase dispersivity by a factor of up to 7.3. The dispersion coefficient (K) was measured as a function of velocity and the data for both dry and water-containing samples were successfully combined on aK–Péclet number (Pe) plot, enabling ready future inclusion into EGR reservoir models. The power-law dependence ofKuponPeproduced an exponent of 1.2 for dry and water-saturated sandstones and 1.4 for dry and water-saturated carbonates, consistent with literature results (Bijeljic et al., 2011, Honari et al., 2015).