Title
Model calibration on cement experiments at realistic CO2 storage conditions
Author
Wasch, L.J.
Koenen, M.
Wollenweber, J.
ter Heege, J.H.
Tambach, T.J.
Publication year
2013
Abstract
Large scale implementation of CO2 storage can significantly reduce emission of greenhouse gasses into the atmosphere. However, safe and long-term containment of CO2 in storage reservoirs must be ensured. Wellbores in the subsurface present possible leakage pathways for CO2 to the surface and hence wellbore cement reactivity is of major concern. Previous experimental studies of cement reactivity often use high brine to cement ratios which may lead to overestimations of the rate of cement alteration. We aim to study cement reactivity under more realistic CO2 storage conditions. Limited brine is used to represent a wellbore environment with brine mainly present in pore space. The experimental results show a cease or significant reduction of reaction progression after 7 days due to saturation of the fluid. This inhibits further cement dissolution and re-dissolution of secondary calcite. The observed reaction zones are matched by geochemical modeling, showing from core to rim: unreacted cement (zone A), portlandite dissolution and increased porosity (zone B), major calcite and reduced porosity plus minor ferrihydrite precipitation (zone Ci) and minor calcite precipitation (zone Cii). The calibration of the geochemical model aids the development of an accurate reactive transport model for long-term cement alteration and integrity prediction.
Subject
Earth / Environmental
SGE - Sustainable Geo Energy
EELS - Earth, Environmental and Life Sciences
Geological Survey Netherlands
Geosciences
Energy / Geological Survey Netherlands
Calcite precipitation
Geochemical modeling
Model calibration
Re-dissolution
Reaction zones
Reactive transport modeling
Storage reservoirs
Unreacted cement
Calcite
Calibration
Carbon dioxide
Dissolution
Earth sciences
Geochemistry
Oil field equipment
Porosity
Cements
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http://resolver.tudelft.nl/uuid:75b19780-c05e-4f49-bf5c-b52a3d2a0c4d
TNO identifier
500707
Source
2nd Sustainable Earth Sciences Conference and Exhibition: Technologies for Sustainable Use of the Deep Sub-Surface, SES 2013, 30 September 2013 through 4 October 2013, Pau, 1-4
Bibliographical note
Sponsors: Statoil; Pau Porte des Pyrenees; Total; Chevron; Shell
Document type
conference paper