Technology Roadmap Low-Carbon Transition in the Cement Industry

Integrating carbon capture, 
storage and utilisation
After being generated in the cement kiln (post-
combustion capture techniques), CO
2
can be 
captured, or purified from kiln flue gases when the 
combustion happens under oxy-fired conditions 
(oxy-fuel capture technologies). Precombustion 
capture technologies have limited mitigation 
potential in cement production, as only energy-
related CO
2
emissions, which represent around 
35% of the total cement carbon emissions, would 
be affected. 
Post‑combustion capture technologies
do not 
require fundamental modifications of cement kilns 
and could be applied to existing facilities provided 
there is enough physical space available on the site:
z
Chemical absorption
35
is the post-combustion 
capture technology that is most advanced, 
and enables up to 95% optimum capture 
yields
36
(ECRA and CSI, 2017). Thermal energy 
is required for regeneration of the sorbent
37
used, and electricity is needed to operate the 
capture unit.
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This would increase the plant 
35. Chemical absorption processes have been commercially used as 
part of core operations in other industrial sectors for a long time.
36. Capture yield is referenced to the gas stream entering the 
capture unit.
37. Amine-based sorbents are most commonly used in CO
2
separating processes, but sorbents that are more efficient, 
based on ammonia or activate potassium carbonate, are being 
investigated.
38. Energy penalties related to chemical absorption for CO
2
capture in cement kilns are reported as 1.0-3.5 GJ/t clinker and 
50-90 kWh/t clinker compared to average operational levels 
(ECRA and CSI, 2017).

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