Chapter 24
Carbon Capture and Storage (CCS)
Helge Hellevang
24.1 Introduction
Carbon Capture and Storage (CCS) involves capturing
CO 2 and then storing it so that it is not emitted to the
atmosphere. The background for CCS is a concern that
increasing atmospheric CO 2 concentrations will cause
global climate changes, ocean acidification and a sea
level rise, with dramatic negative consequences for
large populations (IPCC 2013).
Although capture technologies in principle can be
implemented for any natural gas or flue gas sources,
costs put practical constrains on what kind of
operations that can implement CCS. Generally, any
large point source of CO 2 (>1 Mt CO 2 /year), such as
coal- or gas-fired power plants, natural gas producers
and cement factories, has sufficient CO 2 production to
justify installation of CCS technology. The cost may
however be rather prohibitive.
CO 2 may be captured from major point sources. If
several point sources are in the same geographical
region, then captured CO 2 should be transported to a
common hub before being injected into a geological
formation (Fig. 24.1). This lowers the cost of
implementing the pipeline network and thereby the
total cost of the CCS operation. The geological storage units can be of various kinds, such as saline
aquifers, coal seams and abandoned oil and gas
fields. The requirement is that CO 2 is stored as a
dense supercritical phase (scCO 2 ), that typically
requires more than 700–800 m burial depth, and
that the reservoir has a seal (cap rock), and sufficient
injectivity (porosity and permeability) to store large
volumes of CO 2 . These issues are discussed below.
24.2 CO 2 Capture
Capture refers to the separation of CO 2 from natural
gas or flue (exhaust) gas where the concentration of
CO 2 may be as low as 3–4%. In CCS, capture is
followed by transport and finally underground storage.
There is considerable research activity to improve the
efficiency of present-day capture methods and to
invent new and better technologies, the main motivation being to reduce the cost of the capture process.
Capture, whether it is by pre- or post-combustion,
requires significant amounts of energy. For a coalfired power plant, an extra 20–25% of energy is typically required for capturing and compressing the CO 2 .
There are already several technologies available for
capturing CO 2 . A review of the advances in these
technologies is provided by Figueroa et al. (2008)
and only a brief overview will be given here. In postcombustion capture, CO 2 is removed from flue gases
formed from the combustion of primarily coal. The
coal is burned in an air atmosphere, in contrast to oxycombustion that utilizes an oxygen atmosphere with
little nitrogen. In pre-combustion capture, CO 2 is
removed from the fuel before combustion. This technology is applied to gasification plants. In separating
CO 2 from the gas streams, various technologies are
being used, such as gas-phase separation, sorption to
liquids or solids, and hybrid processes such as sorption/membrane systems. Each of these technologies
has their strengths and weaknesses, and the choice of
H. Hellevang (*)
Department of Geosciences, University of Oslo, Oslo, Norway
e-mail: helge.hellevang@geo.uio.no
K. Bjørlykke (ed.), Petroleum Geoscience: From Sedimentary Environments to Rock Physics,
DOI 10.1007/978-3-642-34132-8_24, # Springer-Verlag Berlin Heidelberg 2015
591
Carbon Capture and Storage (CCS)
Helge Hellevang
24.1 Introduction
Carbon Capture and Storage (CCS) involves capturing
CO 2 and then storing it so that it is not emitted to the
atmosphere. The background for CCS is a concern that
increasing atmospheric CO 2 concentrations will cause
global climate changes, ocean acidification and a sea
level rise, with dramatic negative consequences for
large populations (IPCC 2013).
Although capture technologies in principle can be
implemented for any natural gas or flue gas sources,
costs put practical constrains on what kind of
operations that can implement CCS. Generally, any
large point source of CO 2 (>1 Mt CO 2 /year), such as
coal- or gas-fired power plants, natural gas producers
and cement factories, has sufficient CO 2 production to
justify installation of CCS technology. The cost may
however be rather prohibitive.
CO 2 may be captured from major point sources. If
several point sources are in the same geographical
region, then captured CO 2 should be transported to a
common hub before being injected into a geological
formation (Fig. 24.1). This lowers the cost of
implementing the pipeline network and thereby the
total cost of the CCS operation. The geological storage units can be of various kinds, such as saline
aquifers, coal seams and abandoned oil and gas
fields. The requirement is that CO 2 is stored as a
dense supercritical phase (scCO 2 ), that typically
requires more than 700–800 m burial depth, and
that the reservoir has a seal (cap rock), and sufficient
injectivity (porosity and permeability) to store large
volumes of CO 2 . These issues are discussed below.
24.2 CO 2 Capture
Capture refers to the separation of CO 2 from natural
gas or flue (exhaust) gas where the concentration of
CO 2 may be as low as 3–4%. In CCS, capture is
followed by transport and finally underground storage.
There is considerable research activity to improve the
efficiency of present-day capture methods and to
invent new and better technologies, the main motivation being to reduce the cost of the capture process.
Capture, whether it is by pre- or post-combustion,
requires significant amounts of energy. For a coalfired power plant, an extra 20–25% of energy is typically required for capturing and compressing the CO 2 .
There are already several technologies available for
capturing CO 2 . A review of the advances in these
technologies is provided by Figueroa et al. (2008)
and only a brief overview will be given here. In postcombustion capture, CO 2 is removed from flue gases
formed from the combustion of primarily coal. The
coal is burned in an air atmosphere, in contrast to oxycombustion that utilizes an oxygen atmosphere with
little nitrogen. In pre-combustion capture, CO 2 is
removed from the fuel before combustion. This technology is applied to gasification plants. In separating
CO 2 from the gas streams, various technologies are
being used, such as gas-phase separation, sorption to
liquids or solids, and hybrid processes such as sorption/membrane systems. Each of these technologies
has their strengths and weaknesses, and the choice of
H. Hellevang (*)
Department of Geosciences, University of Oslo, Oslo, Norway
e-mail: helge.hellevang@geo.uio.no
K. Bjørlykke (ed.), Petroleum Geoscience: From Sedimentary Environments to Rock Physics,
DOI 10.1007/978-3-642-34132-8_24, # Springer-Verlag Berlin Heidelberg 2015
591