revue_geosciences16

While geological uncertainties and risks are highly
site specific, the main perceived risks are of potential
leakage, induced seismicity and ground displacement
and their potential impact on health, environment,
resources and value.
Current projects in operation or under development have
the obligation of implementing extensive monitoring
measurements over the long period of injection of
the project and after closure. Further work is ongoing
on project performance and risk control.
Commercial scale CO2 storage requires significant
timelines for large-scale storage systems development,
particularly in regions where little data has been
acquired previously. It also requires the willingness
to accept the level of uncertainties involved as much
technically as financially and in project approval processes
where further work must be undertaken with the
regulatory agencies.
Further research is required in several aspects of CO2
storage, especially at large scale, such as:
– kinetics of trapping mechanisms and their long-term
efficiencies,
– brine withdrawal wells for pressure management, plume
direction control, improved containment capacity,
– geomechanical effects of CO2 injection on wells, reservoirs
and seals in different geological environments
and injection scenarios,
– CO2 stream composition - accompanying elements:
fate and transport,
– development of coupled multi-physics models and
benchmarking to predict the long-term fate of injected
CO2 in the subsurface,
– mitigation and remediation techniques in case of
unexpected behaviour,
– project performance management and risk control
indicators to compare actual and predicted storage
behavior, optimize monitoring and remediation plans,
and address public safety concerns.
At a broader scale, a robust long-term investment
environment must be established.
Outlook
While research needs to continue to increase regulatory
confidence in the long-term safety of storage, there are
no overarching technical barriers to implementing
geologic storage of CO2 in deep saline formations or
depleted oil or gas reservoirs.
un panorama mondial du stockage géologique de dioxyde de carbone
Un panorama mondial du stockage géologique
de dioxyde de carbone
Le captage et stockage
géologique du dioxyde de
carbone (CSC) est une solution
qui peut contribuer de
manière significative à
la réduction des émissions
de dioxyde de carbone (CO2)
dans l’atmosphère, l’une
des causes majeures du
changement climatique.
C’est actuellement l’option
de réduction des émissions
la plus efficace pour
de nombreuses opérations
industrielles.
The identification and evaluation of secure storage sites
is nevertheless a lengthy process and requires significant
investments in time, skilled workforce and finances.
Advancing the characterization of a storage system takes
years before a financial investment decision can be made.
Activities in this area must be accelerated now so that
sufficient proven storage will be available to meet future
demand.
LSIPs will require that decisions be made while a number
of uncertainties regarding storage remain at various stages
of the project lifecycle. Assumptions need to be made
when calculating initial storage capacity, anticipating
the technology that will be available ten years after
the project start, predicting the evolution of legal and
regulatory frameworks, tariffs, fiscal policy, or economic
constraints.
Oil and gas companies have developed frameworks for
dealing with technical and non-technical uncertainties
and risks associated with subsurface development. There
is a critical need to manage these uncertainties in all
aspects of the project, particularly when dealing with
changes in project scope in order to reach milestones
and decision gates.
Finally, stakeholder engagement needs to be fully part
of the project management process, as communicating
the details of storage in an accurate way, as part of a
full communications plan, has proven to be important
for the social feasibility of a project and probably
essential for success.ó
Prouver que le CO2 restera
stocké en toute sécurité et
de façon permanente fait
partie des facteurs les plus
importants pour assurer le
potentiel de cette technologie.
Pour cela, un certain nombre
de sites de stockage
géologiques ont été
développés depuis les années
1990, ce qui demande
une caractérisation avancée
du sous-sol et des processus
de surveillance et d’assurance
élaborés.
Les projets existants apportent
maintenant des connaissances
techniques et opérationnelles
suffisantes au regard de
la sécurité et de la faisabilité
de l’injection de CO2 dans
des aquifères salins profonds
et des réservoirs de pétrole
ou de gaz naturel épuisés.
Cependant, le nombre actuel
de projets CSC à divers stades
de développement est
insuffisant pour limiter
l’augmentation globale
moyenne des températures.
Ceci peut en partie être
expliqué par la longueur
des délais nécessaires au
développement de ces projets
et par l’engagement
significatif que doivent
prendre les porteurs de projet
étant donné que ces sites de
stockage seront opérationnels
pendant des décennies
et doivent remplir nombre
d’obligations réglementaires.
Le nombre insuffisant
de projets résulte aussi
de la faiblesse des revenus
provenant de la vente de CO2
ou de crédits carbone et
d’un cadre juridique et
réglementaire considéré
inadéquat par des porteurs
de projet. Il est urgent que
les politiques publiques
soient réexaminées pour
que des projets viables
puissent se développer.
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