Title: Characterizing the Evolution of Trapped scCO₂ Curvature in Bentheimer and Nugget Sandstone Pore Geometry

Abstract

During a Geologic Carbon Storage process, supercritical CO₂ (scCO₂) is subjected to a series of dynamic and static conditions where the relationship between pore geometry and the trapped scCO₂ curvature remains to be established. To mimic the dynamic process, two sandstones, Bentheimer and Nugget, were subjected to two successive drainage and imbibition (D-I) cycles and X-ray computed tomography scanned at each residual state to capture the wettability evolution at static conditions in the same pore geometry. Both sandstones contain similar grain size distributions, pore size distributions, and pore interconnectivity but differ in that the Nugget formation contains approximately half the porosity of the Bentheimer sandstone, and the pore network contains dead-end pores. scCO₂ size distributions, strain calculations, and geometric contact angle measurements were used to characterize the curvature of scCO₂ in different pore types between cycles. An increase in geometric contact angle was the greatest when advancement along the pore network of the same ganglion occurred between cycles while strain increased the most with pore-filling trapping. Moreover, Nugget sandstone results in a greater aggregated residual saturation and shows a clear increase in scCO₂ sizes with an additional D-I cycle while scCO₂ in the Bentheimer core shows a more complex responsemore » with some ganglion increasing and some decreasing in size with an additional D-I cycle. From this work, we suspect the pore geometry is playing a role in scCO₂ size distributions and use this information to suggest using water pulses to enhance trapping capacity in lower porosity sandstones.« less

Authors:

Dalton, Laura E.  ^[1];

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• Search DOE PAGES for ORCID "0000-0002-3230-8128"

Crandall, Dustin ^[2]; Goodman, Angela ^[2]

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+ Show Author Affiliations

1. National Energy Technology Lab. (NETL), Pittsburgh, PA, and Morgantown, WV (United States). In-house Research; Leidos, Inc., Morgantown, WV (United States)
2. National Energy Technology Lab. (NETL), Pittsburgh, PA, and Morgantown, WV (United States). In-house Research

Publication Date:

Fri Mar 06 00:00:00 EST 2020

Research Org.:

National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV, and Albany, OR (United States)

Sponsoring Org.:

USDOE Office of Fossil Energy (FE)

OSTI Identifier:

1782685

Grant/Contract Number:  

89243318CFE000003

Resource Type:

Accepted Manuscript

Journal Name:

Geofluids

Additional Journal Information:

Journal Volume: 2020; Journal Issue: N/A; Journal ID: ISSN 1468-8115

Publisher:

Hindawi

Country of Publication:

United States

Language:

English

Subject:

58 GEOSCIENCES; contact angle; micro-CT; supercritical CO₂; wettability; sandstone