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conferenceseries
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September 02-03, 2019 | Berlin, Germany
6
th
World Conference on Climate Change
Volume 10
Journal of Earth Science & Climatic Change
ISSN: 2157-7617
Climate Change 2019
September 02-03, 2019
Comprehensive review of chemical and mechanical degradation of well cement in Co
2
environment for
Ccs operations
Priyesh Jani
and
Abdulmohsin Imqam
Missouri University of Science and Technology, USA
Statement of the Problem:
Carbon capture and storage operations reduce emission of carbon dioxide into the
atmosphere which has a large impact on the environment. Long-term storage of carbon dioxide in a reservoir
depends on the degradation of Portland cement used to cast these wells due to carbon dioxide. The objective of this
research is to provide a comprehensive review of past investigations to help understand the cement’s degradation, the
provided solutions to this problem and discuss a potential alternative.
Methodology:
Tables were made with information about the types of cement, the curing conditions and the
exposure conditions (experimental conditions) used in different studies and their conclusions. Tables comprised
of experimental studies conducted on neat Portland cement and cement mix (Portland cement + additives) were
included. Field studies were also discussed. Possible migration paths of CO
2
and exposure conditions that are
likely to happen inside the reservoir were discussed. Quantitative data was extracted from these investigations to
understand the structural changes after the exposure. Histograms were made from the data acquired to determine
the most used type of cement, exposure condition and additive. The data were constructed to explain different curing
and exposure conditions.
Findings:
Data analysis shows that wide ranges of curing and exposure conditions made the comparison of structural
changes impossible between the studies. However, the increase or decrease in porosity, strength, permeability and
density of cement cores after CO
2
exposure, and alteration depths were compared. Mostly, researchers used class
H and class G well cement with CO
2
saturated brine/water at static conditions. Flyash is found to be best known
pozzolan and can be reliably mixed with cement to provide long term integrity in CO
2
storage operations. However,
studies suggest that higher amounts of this additive have a negative impact on the cement mix for this environment.
Flyash-based geopolymer cement was suggested to be used in CO
2
storage operations due to its environmentally
friendly nature and higher durability in CO
2
environment than Portland cement.
Novel Information:
The research provided a critical review about the past investigations, which became helpful in
understanding the degradation process of Portland cement in a CO
2
environment and the behavior of additives. A
new flyash-based geopolymer cement was proposed and discussed.
J Earth Sci Clim Change 2019, Volume: 10