Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions
One of the major concerns of carbon capture and storage (CCS) projects is the prediction of the long-term storage security of injected CO2. When injected underground in saline aquifers or depleted oil and gas fields, CO2mixes with the resident brine to form carbonic acid. The carbonic acid can react...
Published in: | Advances in Water Resources |
---|---|
Main Authors: | , , , |
Other Authors: | |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Elsevier
2018
|
Subjects: | |
Online Access: | http://hdl.handle.net/10044/1/63854 https://doi.org/10.1016/j.advwatres.2018.09.005 |
id |
ftimperialcol:oai:spiral.imperial.ac.uk:10044/1/63854 |
---|---|
record_format |
openpolar |
spelling |
ftimperialcol:oai:spiral.imperial.ac.uk:10044/1/63854 2023-05-15T15:52:35+02:00 Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions Singh, K Anabaraonye, BU Blunt, MJ Crawshaw, J Qatar Shell Research and Technology Center QSTP LLC 2018-09-11 http://hdl.handle.net/10044/1/63854 https://doi.org/10.1016/j.advwatres.2018.09.005 unknown Elsevier Advances in Water Resources © 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license. (http://creativecommons.org/licenses/by/4.0/) CC-BY 36 27 0905 Civil Engineering 0907 Environmental Engineering Environmental Engineering Journal Article 2018 ftimperialcol https://doi.org/10.1016/j.advwatres.2018.09.005 2018-11-01T23:38:41Z One of the major concerns of carbon capture and storage (CCS) projects is the prediction of the long-term storage security of injected CO2. When injected underground in saline aquifers or depleted oil and gas fields, CO2mixes with the resident brine to form carbonic acid. The carbonic acid can react with the host carbonate rock, and alter the rock structure and flow properties. In this study, we have used X-ray micro-tomography and focused ion beam scanning electron microscopy (FIB-SEM) techniques to investigate the dissolution behavior in wettability-altered carbonate rocks at the nm- to µm-scale, to investigate CO2storage in depleted oil fields that have oil-wet or mixed-wet conditions. Our novel procedure of injecting oil after reactive transport has revealed previously unidentified (ghost) regions of partially-dissolved rock grains that were difficult to identify in X-ray tomographic images after dissolution from single fluid phase experiments. We show that these ghost regions have a significantly higher porosity and pore sizes that are an order of magnitude larger than that of unreacted grains. The average thickness of the ghost regions as well as the overall rock dissolution decreases with increasing distance from the injection point. During dissolution micro-porous rock retains much of its original fabric. This suggests that considering the solid part of these ghost regions as macro (bulk) pore space can result in the overestimation of porosity and permeability predicted from segmented X-ray tomographic images, or indeed from reactive transport models that assume a uniform, sharp reaction front at the grain surface. Article in Journal/Newspaper Carbonic acid Imperial College London: Spiral Advances in Water Resources 122 27 36 |
institution |
Open Polar |
collection |
Imperial College London: Spiral |
op_collection_id |
ftimperialcol |
language |
unknown |
topic |
0905 Civil Engineering 0907 Environmental Engineering Environmental Engineering |
spellingShingle |
0905 Civil Engineering 0907 Environmental Engineering Environmental Engineering Singh, K Anabaraonye, BU Blunt, MJ Crawshaw, J Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions |
topic_facet |
0905 Civil Engineering 0907 Environmental Engineering Environmental Engineering |
description |
One of the major concerns of carbon capture and storage (CCS) projects is the prediction of the long-term storage security of injected CO2. When injected underground in saline aquifers or depleted oil and gas fields, CO2mixes with the resident brine to form carbonic acid. The carbonic acid can react with the host carbonate rock, and alter the rock structure and flow properties. In this study, we have used X-ray micro-tomography and focused ion beam scanning electron microscopy (FIB-SEM) techniques to investigate the dissolution behavior in wettability-altered carbonate rocks at the nm- to µm-scale, to investigate CO2storage in depleted oil fields that have oil-wet or mixed-wet conditions. Our novel procedure of injecting oil after reactive transport has revealed previously unidentified (ghost) regions of partially-dissolved rock grains that were difficult to identify in X-ray tomographic images after dissolution from single fluid phase experiments. We show that these ghost regions have a significantly higher porosity and pore sizes that are an order of magnitude larger than that of unreacted grains. The average thickness of the ghost regions as well as the overall rock dissolution decreases with increasing distance from the injection point. During dissolution micro-porous rock retains much of its original fabric. This suggests that considering the solid part of these ghost regions as macro (bulk) pore space can result in the overestimation of porosity and permeability predicted from segmented X-ray tomographic images, or indeed from reactive transport models that assume a uniform, sharp reaction front at the grain surface. |
author2 |
Qatar Shell Research and Technology Center QSTP LLC |
format |
Article in Journal/Newspaper |
author |
Singh, K Anabaraonye, BU Blunt, MJ Crawshaw, J |
author_facet |
Singh, K Anabaraonye, BU Blunt, MJ Crawshaw, J |
author_sort |
Singh, K |
title |
Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions |
title_short |
Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions |
title_full |
Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions |
title_fullStr |
Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions |
title_full_unstemmed |
Partial dissolution of carbonate rock grains during reactive CO 2 -saturated brine injection under reservoir conditions |
title_sort |
partial dissolution of carbonate rock grains during reactive co 2 -saturated brine injection under reservoir conditions |
publisher |
Elsevier |
publishDate |
2018 |
url |
http://hdl.handle.net/10044/1/63854 https://doi.org/10.1016/j.advwatres.2018.09.005 |
genre |
Carbonic acid |
genre_facet |
Carbonic acid |
op_source |
36 27 |
op_relation |
Advances in Water Resources |
op_rights |
© 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license. (http://creativecommons.org/licenses/by/4.0/) |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1016/j.advwatres.2018.09.005 |
container_title |
Advances in Water Resources |
container_volume |
122 |
container_start_page |
27 |
op_container_end_page |
36 |
_version_ |
1766387723676942336 |