Premium
The impact of reservoir conditions on the residual trapping of carbon dioxide in B erea sandstone
Author(s) -
Niu Ben,
AlMenhali Ali,
Krevor Samuel C.
Publication year - 2015
Publication title -
water resources research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.863
H-Index - 217
eISSN - 1944-7973
pISSN - 0043-1397
DOI - 10.1002/2014wr016441
Subject(s) - brine , salinity , residual , saturation (graph theory) , carbon dioxide , capillary pressure , trapping , geology , petroleum engineering , flooding (psychology) , residual oil , environmental science , capillary action , mineralogy , soil science , hydrology (agriculture) , geotechnical engineering , materials science , chemistry , porous medium , composite material , porosity , psychology , ecology , oceanography , mathematics , organic chemistry , algorithm , combinatorics , psychotherapist , biology , computer science
The storage of carbon dioxide in deep brine‐filled permeable rocks is an important tool for CO 2 emissions mitigation on industrial scales. Residual trapping of CO 2 through capillary forces within the pore space of the reservoir is one of the most significant mechanisms for storage security and is also a factor determining the ultimate extent of CO 2 migration within the reservoir. In this study we have evaluated the impact of reservoir conditions of pressure, temperature, and brine salinity on the residual trapping characteristic curve of a fired Berea sandstone rock. The observations demonstrate that the initial‐residual characteristic trapping curve is invariant across a wide range of pressure, temperature, and brine salinities and is also the same for CO 2 ‐brine systems as a N 2 ‐water system. The observations were made using a reservoir condition core‐flooding laboratory that included high‐precision pumps, temperature control, the ability to recirculate fluids for weeks at a time, and an X‐ray CT scanner. Experimental conditions covered pressures of 5–20 MPa, temperatures of 25–50°C, and 0–5 mol/kg NaCl brine salinity. A novel coreflooding approach was developed, making use of the capillary end effect to create a large range in initial CO 2 saturation (0.15–0.6) in a single coreflood. Upon subsequent flooding with CO 2 ‐equilibriated brine, the observation of residual saturation corresponded to the wide range of initial saturations before flooding resulting in a rapid construction of the initial‐residual curve. For each condition we report the initial‐residual curve and the resulting parameterization of the Land hysteresis models.