Page 84 - Çevre Şehir İklim İngilizce - Sayı 1

The Role of Carbon Technologies in the
"Net Zero" Target

is released into the atmosphere (PCA, 2022). During this process, there is no
alternative to limestone and CO emission that is not related to burning fossil
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fuels, but result from the process is inevitable. Surely, the important steps
taken since the 1990s (such as increasing the efficiency of cement kilns, using
alternative fuels with waste biomass fraction and using additional clinker)
enabled mitigation of over 20% of emissions. These developments, however,
are not sufficient for intensive mitigation of CO emission to reach “net zero“
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carbon emission. Consequently, as there is no proven alternative method for
cement production, the only option is to capture the CO released during
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cement production and store it permanently. The CO concentration of the
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flue gas from cement factories is around 14-33% and it is a good candidate for
CCUS (Bosoaga, Masek, & Oakey, 2009)especially CO , have to be reduced
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by 50-80% by 2050, according to the IPCC [1]. The type of fuel used in cement
manufacture directly impacts on CO emissions, with coal accounting for
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around 60-70% of CO emissions from cement installations. Therefore, the
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large amount of carbon dioxide emitted during cement manufacturing process
- 5% of the total emissions of CO from stationary sources worldwide - is a
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cause of great concern and has to be tack led in order to comply with current
legislation. Several technologies are available and have been proposed for
the separation of CO from the flue gases from new and existing plants with
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retrofit capture units. Few studies have been undertaken on CO capture in
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cement plants to assess the suitable technologies, with oxy-combustion and
amine scrubbing as the possible options (pre-combustion capture not being
viable. Although there is no active commercial-scale facility for that in cement
sector, studies towards developing carbon capture technologies are underway.
One of the major research and development activities is implemented in the
Norcem Brevik cement factory in Norway. In 2024, it is planned to put the
factory into service. It will be the first-ever cement factory with the facility
to capture CO . The facility utilizes amine chemical compounds to capture
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CO and a solvent-based technology to separate gas and liquid. The energy
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required for energy-intensive desorption is provided by the cement factory’s
waste heat. The captured CO is compressed to turn it into liquid, which will
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then be transported to Kallness storage facility by ship and stored in the
open sea. With this CCS facility, 55 tons of CO per hour, and 0.4 Mt of CO
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per year will be captured and stored (Norcem, 2022). Moreover, the same
cement company is also developing an oxy-fuel cement kiln which utilizes
pure oxygen instead of air and thus increases CO concentration to 70% or
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over (Beumelburg, 2021). Higher CO concentrations make any CO capture
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more efficient and reduce the waste gas volume to a great extent, thus also
reducing the costs considerably. Another example is a project started by
Calix, an Austrian-based company, designed to apply the calcination reaction

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